Centromere: The clear constricted portion of the chromosome at which the chromatids are joined and by which the chromosome is attached to the spindle during cell division.Centromere Protein B: A DNA-binding protein that interacts with a 17-base pair sequence known as the CENP-B box motif. The protein is localized constitutively to the CENTROMERE and plays an important role in its maintenance.Chromosomal Proteins, Non-Histone: Nucleoproteins, which in contrast to HISTONES, are acid insoluble. They are involved in chromosomal functions; e.g. they bind selectively to DNA, stimulate transcription resulting in tissue-specific RNA synthesis and undergo specific changes in response to various hormones or phytomitogens.Kinetochores: Large multiprotein complexes that bind the centromeres of the chromosomes to the microtubules of the mitotic spindle during metaphase in the cell cycle.Chromosome Segregation: The orderly segregation of CHROMOSOMES during MEIOSIS or MITOSIS.DNA, Satellite: Highly repetitive DNA sequences found in HETEROCHROMATIN, mainly near centromeres. They are composed of simple sequences (very short) (see MINISATELLITE REPEATS) repeated in tandem many times to form large blocks of sequence. Additionally, following the accumulation of mutations, these blocks of repeats have been repeated in tandem themselves. The degree of repetition is on the order of 1000 to 10 million at each locus. Loci are few, usually one or two per chromosome. They were called satellites since in density gradients, they often sediment as distinct, satellite bands separate from the bulk of genomic DNA owing to a distinct BASE COMPOSITION.Chromosomes: In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Chromosomes, Fungal: Structures within the nucleus of fungal cells consisting of or containing DNA, which carry genetic information essential to the cell.Mitosis: A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.Autoantigens: Endogenous tissue constituents that have the ability to interact with AUTOANTIBODIES and cause an immune response.Heterochromatin: The portion of chromosome material that remains condensed and is transcriptionally inactive during INTERPHASE.Meiosis: A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.In Situ Hybridization, Fluorescence: A type of IN SITU HYBRIDIZATION in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei.Chromosomes, Artificial, Human: DNA constructs that are composed of, at least, all elements, such as a REPLICATION ORIGIN; TELOMERE; and CENTROMERE, required for successful replication, propagation to and maintainance in progeny human cells. In addition, they are constructed to carry other sequences for analysis or gene transfer.Schizosaccharomyces: A genus of ascomycetous fungi of the family Schizosaccharomycetaceae, order Schizosaccharomycetales.Metaphase: The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.Chromatids: Either of the two longitudinally adjacent threads formed when a eukaryotic chromosome replicates prior to mitosis. The chromatids are held together at the centromere. Sister chromatids are derived from the same chromosome. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Histones: Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.Chromosomes, Plant: Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of PLANTS.Anaphase: The phase of cell nucleus division following METAPHASE, in which the CHROMATIDS separate and migrate to opposite poles of the spindle.Aurora Kinase B: An aurora kinase that is a component of the chromosomal passenger protein complex and is involved in the regulation of MITOSIS. It mediates proper CHROMOSOME SEGREGATION and contractile ring function during CYTOKINESIS.Spindle Apparatus: A microtubule structure that forms during CELL DIVISION. It consists of two SPINDLE POLES, and sets of MICROTUBULES that may include the astral microtubules, the polar microtubules, and the kinetochore microtubules.DNA, Fungal: Deoxyribonucleic acid that makes up the genetic material of fungi.Chromatin: The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.Schizosaccharomyces pombe Proteins: Proteins obtained from the species Schizosaccharomyces pombe. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.Aurora Kinases: A family of highly conserved serine-threonine kinases that are involved in the regulation of MITOSIS. They are involved in many aspects of cell division, including centrosome duplication, SPINDLE APPARATUS formation, chromosome alignment, attachment to the spindle, checkpoint activation, and CYTOKINESIS.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Cell Cycle Proteins: Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.Muntjacs: A genus, Muntiacus, of the deer family (Cervidae) comprising six species living in China, Tibet, Nepal, India, the Malay Peninsula, and neighboring island countries. They are usually found in forests and areas of dense vegetation, usually not far from water. They emit a deep barklike sound which gives them the name "barking deer." If they sense a predator they will "bark" for an hour or more. They are hunted for their meat and skins; they thrive in captivity and are found in many zoos. The Indian muntjac is believed to have the lowest chromosome number in mammals and cell lines derived from them figure widely in chromosome and DNA studies. (From Walker's Mammals of the World, 5th ed., p1366)Chromosomes, Human: Very long DNA molecules and associated proteins, HISTONES, and non-histone chromosomal proteins (CHROMOSOMAL PROTEINS, NON-HISTONE). Normally 46 chromosomes, including two sex chromosomes are found in the nucleus of human cells. They carry the hereditary information of the individual.Chromosome Pairing: The alignment of CHROMOSOMES at homologous sequences.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Synaptonemal Complex: The three-part structure of ribbon-like proteinaceous material that serves to align and join the paired homologous CHROMOSOMES. It is formed during the ZYGOTENE STAGE of the first meiotic division. It is a prerequisite for CROSSING OVER.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Prophase: The first phase of cell nucleus division, in which the CHROMOSOMES become visible, the CELL NUCLEUS starts to lose its identity, the SPINDLE APPARATUS appears, and the CENTRIOLES migrate toward opposite poles.Saccharomyces cerevisiae Proteins: Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Nondisjunction, Genetic: The failure of homologous CHROMOSOMES or CHROMATIDS to segregate during MITOSIS or MEIOSIS with the result that one daughter cell has both of a pair of parental chromosomes or chromatids and the other has none.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Isochromosomes: Metacentric chromosomes produced during MEIOSIS or MITOSIS when the CENTROMERE splits transversely instead of longitudinally. The chromosomes produced by this abnormal division are one chromosome having the two long arms of the original chromosome, but no short arms, and the other chromosome consisting of the two short arms and no long arms. Each of these isochromosomes constitutes a simultaneous duplication and deletion.Interphase: The interval between two successive CELL DIVISIONS during which the CHROMOSOMES are not individually distinguishable. It is composed of the G phases (G1 PHASE; G0 PHASE; G2 PHASE) and S PHASE (when DNA replication occurs).Nucleosomes: The repeating structural units of chromatin, each consisting of approximately 200 base pairs of DNA wound around a protein core. This core is composed of the histones H2A, H2B, H3, and H4.Telomere: A terminal section of a chromosome which has a specialized structure and which is involved in chromosomal replication and stability. Its length is believed to be a few hundred base pairs.Meiotic Prophase I: The prophase of the first division of MEIOSIS (in which homologous CHROMOSOME SEGREGATION occurs). It is divided into five stages: leptonema, zygonema, PACHYNEMA, diplonema, and diakinesis.Fungal Proteins: Proteins found in any species of fungus.Telophase: The final phase of cell nucleus division following ANAPHASE, in which two daughter nuclei are formed, the CYTOPLASM completes division, and the CHROMOSOMES lose their distinctness and are transformed into CHROMATIN threads.Nuclear Proteins: Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.Repetitive Sequences, Nucleic Acid: Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).CREST Syndrome: A mild form of LIMITED SCLERODERMA, a multi-system disorder. Its features include symptoms of CALCINOSIS; RAYNAUD DISEASE; ESOPHAGEAL MOTILITY DISORDERS; sclerodactyly, and TELANGIECTASIS. When the defect in esophageal function is not prominent, it is known as CRST syndrome.Microtubules: Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.Euchromatin: Chromosome regions that are loosely packaged and more accessible to RNA polymerases than HETEROCHROMATIN. These regions also stain differentially in CHROMOSOME BANDING preparations.Recombination, Genetic: Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.Retroelements: Elements that are transcribed into RNA, reverse-transcribed into DNA and then inserted into a new site in the genome. Long terminal repeats (LTRs) similar to those from retroviruses are contained in retrotransposons and retrovirus-like elements. Retroposons, such as LONG INTERSPERSED NUCLEOTIDE ELEMENTS and SHORT INTERSPERSED NUCLEOTIDE ELEMENTS do not contain LTRs.Zea mays: A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.Chromosome Positioning: The mechanisms of eukaryotic CELLS that place or keep the CHROMOSOMES in a particular SUBNUCLEAR SPACE.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Saccharomycetales: An order of fungi in the phylum Ascomycota that multiply by budding. They include the telomorphic ascomycetous yeasts which are found in a very wide range of habitats.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Crossing Over, Genetic: The reciprocal exchange of segments at corresponding positions along pairs of homologous CHROMOSOMES by symmetrical breakage and crosswise rejoining forming cross-over sites (HOLLIDAY JUNCTIONS) that are resolved during CHROMOSOME SEGREGATION. Crossing-over typically occurs during MEIOSIS but it may also occur in the absence of meiosis, for example, with bacterial chromosomes, organelle chromosomes, or somatic cell nuclear chromosomes.Genes, Fungal: The functional hereditary units of FUNGI.DNA, Plant: Deoxyribonucleic acid that makes up the genetic material of plants.Spermatocytes: Male germ cells derived from SPERMATOGONIA. The euploid primary spermatocytes undergo MEIOSIS and give rise to the haploid secondary spermatocytes which in turn give rise to SPERMATIDS.Chromosome Banding: Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.Karyotyping: Mapping of the KARYOTYPE of a cell.Chromosome Structures: Structures which are contained in or part of CHROMOSOMES.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Sister Chromatid Exchange: An exchange of segments between the sister chromatids of a chromosome, either between the sister chromatids of a meiotic tetrad or between the sister chromatids of a duplicated somatic chromosome. Its frequency is increased by ultraviolet and ionizing radiation and other mutagenic agents and is particularly high in BLOOM SYNDROME.Chromosomes, Artificial, Bacterial: DNA constructs that are composed of, at least, a REPLICATION ORIGIN, for successful replication, propagation to and maintenance as an extra chromosome in bacteria. In addition, they can carry large amounts (about 200 kilobases) of other sequence for a variety of bioengineering purposes.Chromosomes, Artificial, Mammalian: DNA constructs that are composed of, at least, all elements, such as a REPLICATION ORIGIN; TELOMERE; and CENTROMERE, that are required for successful replication, propagation to and maintainance in progeny mammalian cells. In addition, they are constructed to carry other sequences for analysis or gene transfer.Scrophulariaceae: The figwort plant family of the order Lamiales. The family is characterized by bisexual flowers with tubular corollas (fused petals) that are bilaterally symmetrical (two-lips) and have four stamens in most, two of which are usually shorter.Basic Helix-Loop-Helix Leucine Zipper Transcription Factors: A family of transcription factors that contain regions rich in basic residues, LEUCINE ZIPPER domains, and HELIX-LOOP-HELIX MOTIFS.Cell Cycle: The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Chromatin Assembly and Disassembly: The mechanisms effecting establishment, maintenance, and modification of that specific physical conformation of CHROMATIN determining the transcriptional accessibility or inaccessibility of the DNA.Physical Chromosome Mapping: Mapping of the linear order of genes on a chromosome with units indicating their distances by using methods other than genetic recombination. These methods include nucleotide sequencing, overlapping deletions in polytene chromosomes, and electron micrography of heteroduplex DNA. (From King & Stansfield, A Dictionary of Genetics, 5th ed)Genetic Markers: A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.DNA, Catenated: CIRCULAR DNA that is interlaced together as links in a chain. It is used as an assay for the activity of DNA TOPOISOMERASES. Catenated DNA is attached loop to loop in contrast to CONCATENATED DNA which is attached end to end.Aneuploidy: The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).Chromosomal Instability: An increased tendency to acquire CHROMOSOME ABERRATIONS when various processes involved in chromosome replication, repair, or segregation are dysfunctional.Microtubule-Associated Proteins: High molecular weight proteins found in the MICROTUBULES of the cytoskeletal system. Under certain conditions they are required for TUBULIN assembly into the microtubules and stabilize the assembled microtubules.Chromosomes, Mammalian: Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of MAMMALS.

All 16 centromere DNAs from Saccharomyces cerevisiae show DNA curvature. (1/2290)

All 16 centromere DNA regions of Saccharomyces cerevisiae including 90 bp framing sequences on either side were cloned. These 300 bp long centromere regions were analysed by native polyacrylamide gel electrophoresis and found to display a reduced mobility indicative of DNA curvature. The degree of curvature is centromere dependent. The experimental data were confirmed by computer analysis of the 3-dimensional structure of the CEN DNAs. Altogether these data provide further evidence for a model for budding yeast centromeres in which CEN DNA structure could be important for the assembly, activity and/or regulation of the centromere protein-DNA complex.  (+info)

Localization and properties of a silencing element near the mat3-M mating-type cassette of Schizosaccharomyces pombe. (2/2290)

Transcription is repressed in a segment of Schizosaccharomyces pombe chromosome II that encompasses the mat2-P and mat3-M mating-type cassettes. Chromosomal deletion analysis revealed the presence of a repressor element within 500 bp of mat3-M. This element acted in synergy with the trans-acting factors Swi6, Clr1, Clr2, Clr3, and Clr4 and had several properties characteristic of silencers: it did not display promoter specificity, being able to silence not only the M mating-type genes but also the S. pombe ura4 and ade6 genes placed on the centromere-distal side of the mat3-M cassette; it could repress a gene when placed further than 2.6 kb from the promoter and it acted in both orientations, although with different efficiencies, the natural orientation repressing more stringently than the reverse. Following deletion of this element, two semistable states of expression of the mat3-M region were observed and these two states could interconvert. The deletion did not affect gene expression in the vicinity of the mat2-P cassette, 11 kb away from mat3-M. Conversely, deleting 1.5 kb on the centromere-proximal side of the mat2-P cassette, which was previously shown to partially derepress transcription around mat2-P, had no effect on gene expression near mat3-M. A double deletion removing the mat2-P and mat3-M repressor elements had the same effect as the single deletions on their respective cassettes when assayed in cells of the M mating type. These observations allow us to refine a model proposing that redundant pathways silence the mating type region of S. pombe.  (+info)

A new X linked neurodegenerative syndrome with mental retardation, blindness, convulsions, spasticity, mild hypomyelination, and early death maps to the pericentromeric region. (3/2290)

We report on a family with an X linked neurodegenerative disorder consisting of mental retardation, blindness, convulsions, spasticity, and early death. Neuropathological examination showed mild hypomyelination. By linkage analysis, the underlying genetic defect could be assigned to the pericentromeric region of the X chromosome with a maximum lod score of 3.30 at theta=0.0 for the DXS1204 locus with DXS337 and PGK1P1 as flanking markers.  (+info)

Short DNA fragments without sequence similarity are initiation sites for replication in the chromosome of the yeast Yarrowia lipolytica. (4/2290)

We have previously shown that both a centromere (CEN) and a replication origin are necessary for plasmid maintenance in the yeast Yarrowia lipolytica (). Because of this requirement, only a small number of centromere-proximal replication origins have been isolated from Yarrowia. We used a CEN-based plasmid to obtain noncentromeric origins, and several new fragments, some unique and some repetitive sequences, were isolated. Some of them were analyzed by two-dimensional gel electrophoresis and correspond to actual sites of initiation (ORI) on the chromosome. We observed that a 125-bp fragment is sufficient for a functional ORI on plasmid, and that chromosomal origins moved to ectopic sites on the chromosome continue to act as initiation sites. These Yarrowia origins share an 8-bp motif, which is not essential for origin function on plasmids. The Yarrowia origins do not display any obvious common structural features, like bent DNA or DNA unwinding elements, generally present at or near eukaryotic replication origins. Y. lipolytica origins thus share features of those in the unicellular Saccharomyces cerevisiae and in multicellular eukaryotes: they are discrete and short genetic elements without sequence similarity.  (+info)

Analysis of the 10q23 chromosomal region and the PTEN gene in human sporadic breast carcinoma. (5/2290)

We examined a panel of sporadic breast carcinomas for loss of heterozygosity (LOH) in a 10-cM interval on chromosome 10 known to encompass the PTEN gene. We detected allele loss in 27 of 70 breast tumour DNAs. Fifteen of these showed loss limited to a subregion of the area studied. The most commonly deleted region was flanked by D10S215 and D10S541 and encompasses the PTEN locus. We used a combination of denaturing gradient gel electrophoresis and single-strand conformation polymorphism analyses to investigate the presence of PTEN mutations in tumours with LOH in this region. We did not detect mutations of PTEN in any of these tumours. Our data show that, in sporadic breast carcinoma, loss of heterozygosity of the PTEN locus is frequent, but mutation of PTEN is not. These results are consistent with loss of another unidentified tumour suppressor in this region in sporadic breast carcinoma.  (+info)

Specific destruction of kinetochore protein CENP-C and disruption of cell division by herpes simplex virus immediate-early protein Vmw110. (6/2290)

Examination of cells at the early stages of herpes simplex virus type 1 infection revealed that the viral immediate-early protein Vmw110 (also known as ICP0) formed discrete punctate accumulations associated with centromeres in both mitotic and interphase cells. The RING finger domain of Vmw110 (but not the C-terminal region) was essential for its localization at centromeres, thus distinguishing the Vmw110 sequences required for centromere association from those required for its localization at other discrete nuclear structures known as ND10, promyelocytic leukaemia (PML) bodies or PODs. We have shown recently that Vmw110 can induce the proteasome-dependent loss of several cellular proteins, including a number of probable SUMO-1-conjugated isoforms of PML, and this results in the disruption of ND10. In this study, we found some striking similarities between the interactions of Vmw110 with ND10 and centromeres. Specifically, centromeric protein CENP-C was lost from centromeres during virus infection in a Vmw110- and proteasome-dependent manner, causing substantial ultrastructural changes in the kinetochore. In consequence, dividing cells either became stalled in mitosis or underwent an unusual cytokinesis resulting in daughter cells with many micronuclei. These results emphasize the importance of CENP-C for mitotic progression and suggest that Vmw110 may be interfering with biochemical mechanisms which are relevant to both centromeres and ND10.  (+info)

Dynamic repositioning of genes in the nucleus of lymphocytes preparing for cell division. (7/2290)

We show that several transcriptionally inactive genes localize to centromeric heterochromatin in the nucleus of cycling but not quiescent (noncycling) primary B lymphocytes. In quiescent cells, centromeric repositioning of inactive loci was induced after mitogenic stimulation. A dynamic repositioning of selected genes was also observed in developing T cells. Rag and TdT loci were shown to relocate to centromeric domains following heritable gene silencing in primary CD4+8+ thymocytes, but not in a phenotypically similar cell line in which silencing occurred but was not heritable. Collectively, these data indicate that the spatial organization of genes in cycling and noncycling lymphocytes is different and that locus repositioning may be a feature of heritable gene silencing.  (+info)

Probing the Saccharomyces cerevisiae centromeric DNA (CEN DNA)-binding factor 3 (CBF3) kinetochore complex by using atomic force microscopy. (8/2290)

Yeast centromeric DNA (CEN DNA) binding factor 3 (CBF3) is a multisubunit protein complex that binds to the essential CDEIII element in CEN DNA. The four CBF3 proteins are required for accurate chromosome segregation and are considered to be core components of the yeast kinetochore. We have examined the structure of the CBF3-CEN DNA complex by atomic force microscopy. Assembly of CBF3-CEN DNA complexes was performed by combining purified CBF3 proteins with a DNA fragment that includes the CEN region from yeast chromosome III. Atomic force microscopy images showed DNA molecules with attached globular bodies. The contour length of the DNA containing the complex is approximately 9% shorter than the DNA alone, suggesting some winding of DNA within the complex. The measured location of the single binding site indicates that the complex is located asymmetrically to the right of CDEIII extending away from CDEI and CDEII, which is consistent with previous data. The CEN DNA is bent approximately 55 degrees at the site of complex formation. A significant fraction of the complexes are linked in pairs, showing three to four DNA arms, with molecular volumes approximately three times the mean volumes of two-armed complexes. These multi-armed complexes indicate that CBF3 can bind two DNA molecules together in vitro and, thus, may be involved in holding together chromatid pairs during mitosis.  (+info)

Centromere function requires the proper coordination of several subfunctions, such as kinetochore assembly, sister chromatid cohesion, binding of kinetochore microtubules, orientation of sister kinetochores to opposite spindle poles, and their movement towards the spindle poles. Centromere structure appears to be organized in different, separable domains in order to accomplish these functions. Despite the conserved nature of centromere functions, the molecular genetic definition of the DNA sequences that form a centromere in the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, in the fruit fly Drosophila melanogaster, and in humans has revealed little conservation at the level of centromere DNA sequences. Also at the protein level few centromere proteins are conserved in all of these four organisms and many are unique to the different organisms. The recent analysis of the centromere structure in the yeast S. pombe by electron microscopy and detailed immunofluorescence microscopy of ...
The histone protein CenH3 is both necessary and sufficient to trigger the formation of centromeres and pass them on from 1 generation to the next. Centromeres are specialised regions of the genome, which can be identified under the microscope as the primary constriction in X-shaped chromosomes. The cell skeleton, which distributes the chromosomes to the two daughter cells during cell division, attaches to the centromeres. In most organisms the position of the centromere is not determined by the DNA sequence. Scientists from the Max Planck Institute of Immunobiology and Epigenetics in Freiburg have succeeded in demonstrating that the position, function and inheritance of the centromere are determined by the histone CenH3, a DNA packaging protein. This discovery may help to further the development of artificial human chromosomes, which could be used for gene therapies in medicine.. Centromeres provide a platform for the development of a protein complex known as the kinetochore. During cell ...
Our results show for the first time that mouse SGO2 localizes at the inner centromere domain during both meiotic and mitotic divisions, in the same way as its orthologue Sgo2 in fission yeast (Kitajima et al, 2004; Rabitsch et al, 2004). SGO2 and RAD21 colocalize and show a double cornet arrangement at the inner centromere domain below the closely associated sister kinetochores during metaphase I and anaphase I. By contrast, REC8 colocalizes only with the vertical region of the T‐shaped SGO2 signals during these stages (supplementary Fig 4 online). These results show that there are two different cohesin complexes with either RAD21 or REC8 at the inner domain of metaphase I and anaphase I centromeres, and that these complexes coexist only at the vertical region of the T‐shaped SGO2 signals. Thus, SGO2, as has been proposed for Sgo1 in Drosophila and yeast meiosis (Kitajima et al, 2004; Marston et al, 2004; Rabitsch et al, 2004; Clarke et al, 2005), could protect centromeric cohesin ...
The accurate distribution of genetic information to daughter cells during cell division relies on the physical attachment of chromosomes to spindle microtubules mediated by kinetochores. Kinetochores are large protein assemblies deposited at specific chromosomal loci known as centromeres [1], [2], [3]. Defective centromere function results in chromosome segregation errors that can contribute to genomic instability implicated in cancer [4]. Hence, understanding the molecular mechanisms that promote kinetochore establishment and maintenance at centromeres is of prime importance.. The location of most eukaryotic centromeres is determined by the assembly of specialized chromatin composed of nucleosomes in which canonical histone H3 is replaced by the centromere‐specific H3 variant CENP‐A in vertebrates and Cnp1 (CENP‐ACnp1) in Schizosaccharomyces pombe [3], [5]. Thus, the establishment and maintenance of kinetochores requires CENP‐A to be recruited to and deposited at centromeres. In S. ...
Centromere DNA element II (CDEII) of budding yeast centromeres is an AT-rich sequence essential for centromere (CEN) function. Sequence analysis of Saccharomyces cerevisiae CDEIIs revealed that A(5-7)/T(5-7) tracts are statistically overrepresented at the expense of AA/TT and alternating AT. To test the hypothesis that this nonrandom sequence organization is functionally important, a CEN library in which the CDEII sequences were randomized was generated. The library was screened for functional and nonfunctional members following centromere replacement in vivo. Functional CENs contained CDEIIs with the highly biased A(n)/T(n) run distribution of native centromeres, while nonfunctional CDEIIs resembled those picked from the library at random. Run content, defined as the fraction of residues present in runs of four or more nucleotides, of the functional and nonfunctional CDEII populations differed significantly (P | 0.001). Computer searches of the genome for regions with an A + T content comparable to
We have employed a system that utilizes homologous pairs of human DNA-derived yeast artificial chromosomes (YACs) as marker chromosomes to assess the specific role(s) of conserved centromere DNA elements (CDEI, CDEII and CDEIII) in meiotic chromosome disjunction fidelity. Thirteen different centromere (CEN) mutations were tested for their effects on meiotic centromere function. YACs containing a wild-type CEN DNA sequence segregate with high fidelity in meiosis I (99% normal segregation) and in meiosis II (96% normal segregation). YACs containing a 31-bp deletion mutation in centromere DNA element II (CDEII delta 31) in either a heterocentric (mutant/wild type), homocentric (mutant/mutant) or monosomic (mutant/--) YAC pair configuration exhibited high levels (16-28%) of precocious sister-chromatid segregation (PSS) and increased levels (1-6%) of nondisjunction meiosis I (NDI). YACs containing this mutation also exhibit high levels (21%) of meiosis II nondisjunction. Interestingly, significant ...
The HTR12 protein is a centromere-specific histone H3 variant in A. thaliana, and was shown to colocalize with the 180 bp repetitive sequences of all centromeres (Talbert et al., 2002). The Zea mays centromeric histone H3, CENH3 was also detected at the kinetochore regions of the centromere and colocalized with centromere-specific tandem repeat CentC and with centromeric retroelement CRM (Zhong et al., 2002). These results indicate wide conservation of CENP-A-like proteins and their close relationship to the centromeric satellites. In our study, the spatial relationship between HTR12 protein and 180 bp repetitive sequences was investigated by sequential combination of immunolabeling and FISH. In the cell cultures studied here, drastic changes in the copy numbers of 180 bp repetitive sequences had occurred, however, all chromosomes carried the 180 bp repetitive sequences despite their variation in size (Fig. 1E,F). For chromosomes with low numbers of 180 bp repetitive sequences, ...
TY - JOUR. T1 - Involvement of the spliceosomal U4 small nuclear RNA in heterochromatic gene silencing at fission yeast centromeres. AU - Chinen, Madoka. AU - Morita, Misato. AU - Fukumura, Kazuhiro. AU - Tani, Tokio. PY - 2010/2/19. Y1 - 2010/2/19. N2 - prp13-1 is one of the mutants isolated in a screen for defective pre-mRNA splicing at a nonpermissive temperature in fission yeast Schizosaccharomyces pombe. We cloned the prp13+ gene and found that it encodes U4 small nuclear RNA (snRNA) involved in the assembly of the spliceosome. The prp13-1 mutant produced elongated cells, a phenotype similar to cell division cycle mutants, and displays a high incidence of lagging chromosomes on anaphase spindles. The mutant is hypersensitive to the microtubule-destabilizing drug thiabendazole, supporting that prp13-1 has a defect in chromosomal segregation. We found that the prp13-1 mutation resulted in expression of the ura4 + gene inserted in the pericentromeric heterochromatin region and reduced ...
TY - JOUR. T1 - Meiosis-Specific loading of the Centromere-Specific histone CENH3 in Arabidopsis thaliana. AU - Ravi, Maruthachalam. AU - Shibata, Fukashi. AU - Ramahi, Joseph S.. AU - Nagaki, Kiyotaka. AU - Chen, Changbin. AU - Murata, Minoru. AU - Chan, Simon W L. PY - 2011/6. Y1 - 2011/6. N2 - Centromere behavior is specialized in meiosis I, so that sister chromatids of homologous chromosomes are pulled toward the same side of the spindle (through kinetochore mono-orientation) and chromosome number is reduced. Factors required for mono-orientation have been identified in yeast. However, comparatively little is known about how meiotic centromere behavior is specialized in animals and plants that typically have large tandem repeat centromeres. Kinetochores are nucleated by the centromere-specific histone CENH3. Unlike conventional histone H3s, CENH3 is rapidly evolving, particularly in its N-terminal tail domain. Here we describe chimeric variants of CENH3 with alterations in the N-terminal ...
The kinetochore directs accurate chromosome segregation by controlling chromosome movements through interactions with spindle microtubules, and also by serving as a platform for various regulatory pathways. Kinetochores assemble on centromere chromatin marked by nucleosomes containing the centromere-specific histone H3 variant CENP-A (Allshire and Karpen, 2008; Earnshaw and Rothfield, 1985). The interphase centromere complex (ICEN) associates with the CENP-A nucleosome (Izuta et al., 2006; Obuse et al., 2004), and the constitutive-centromere-associated network (CCAN) forms the inner kinetochore (Basilico et al., 2014; Cheeseman and Desai, 2008; Foltz et al., 2006; Gascoigne et al., 2011; Hori et al., 2008; Okada et al., 2006). The CCAN factors CENP-C (Saitoh et al., 1992) and CENP-T act as a crucial platform for the kinetochore during mitosis (Gascoigne et al., 2011; Hori et al., 2008, 2013; Nishino et al., 2013; Przewloka et al., 2011; Rago et al., 2015). CENP-C binds to CENP-A nucleosomes ...
TY - JOUR. T1 - Precise centromere mapping using a combination of repeat junction markers and chromatin immunoprecipitation-polymerase chain reaction. AU - Luce, Amy C.. AU - Sharma, Anupma. AU - Mollere, Oliver S.B.. AU - Wolfgruber, Thomas K.. AU - Nagaki, Kiyotaka. AU - Jiang, Jiming. AU - Presting, Gernot G.. AU - Dawe, R. Kelly. PY - 2006/11/6. Y1 - 2006/11/6. N2 - Centromeres are difficult to map even in species where genetic resolution is excellent. Here we show that junctions between repeats provide reliable single-copy markers for recombinant inbred mapping within centromeres and pericentromeric heterochromatin. Repeat junction mapping was combined with anti-CENH3-mediated ChIP to provide a definitive map position for maize centromere 8.. AB - Centromeres are difficult to map even in species where genetic resolution is excellent. Here we show that junctions between repeats provide reliable single-copy markers for recombinant inbred mapping within centromeres and pericentromeric ...
Neocentromere activation requires centromere juxtaposition: Here we describe irradiation-mutagenesis experiments designed to identify the mechanism of neocentromere formation in D. melanogaster. Prior to this study, two models existed to explain the generation of neocentromeres in Drosophila and Homo sapiens-derepression of latent centromere-competent euchromatic sequences vs. centromere spreading (Choo 1997a, 1998). We distinguished between these models through a genetic assay for neocentromere activation and recovery. Three substrate chromosomes were irradiated, and an identical 290-kb test segment was liberated and genetically assayed for neocentromere activity. The three test segments were identical in molecular structure and differed only in their chromosomal context. In Dpγ238, the test segment was juxtaposed to an active centromere; in Dp8-23, the test segment was juxtaposed to centric, but centromerically inert DNA; in Tγ1337, the test segment was juxtaposed to euchromatin. ...
Centromeres are unique chromatin domains that direct the site of kinetochore formation during mitosis and mediate the movement of chromosomes during cell division. Centromeres contain a unique nucleosome in which histone H3 is replaced by centromere protein A (CENP-A). Because of their unique position in chromatin, the CENP-A nucleosome was hypothesized to determine the site of centromere and kinetochore assembly. In order to test the long held assumption that CENP-A dictates the location of the centromere; we developed a novel de novo centromere formation assay, which provides a new and powerful constructive approach to studying centromeres. This system is based on a LacO array that is stably integrated into the long arm of chromosome 1, far away from the existing centromere. Targeting the CENP-A chaperone HJURP or the Mis18 complex to the LacO array, by fusing them to the LacI repressor, drove the stable recruitment of CENP-A nucleosomes to the LacO array at the non-centromeric locus. ...
Centromeres mediate the conserved and essential process of chromosome segregation, yet centromeric DNA and the centromeric histone, CENP-A, are rapidly evolving. The rapid evolution of loop 1 (L1) of Drosophila CENP-A is thought to modulate the DNA-binding preferences of CENP-A to suppress centromere drive, the preferential transmission of chromosomes with expanded centromeric satellites during female meiosis. Consistent with this model, CENP-A from D. bipectinata (bip) fails to localize to D. melanogaster (mel) centromeres due to amino acid differences between mel and bip L1. Here, I show that this result is, in fact, due to the inability of the mel CENP-A chaperone, CAL1, to incorporate bip CENP-A into chromatin. Co-expression of bip CENP-A and bip CAL1 in mel cells restores centromeric localization, and similar findings apply to other Drosophila species. Furthermore, two co-evolving regions, CENP-A L1 and the CAL1 N-terminus, are identified as critical for lineage-specific CENP-A incorporation.
Centromeres are the differentiated chromosomal domains that specify the mitotic behavior of chromosomes. To examine the molecular basis for the specification of centromeric chromatin, we have cloned a human cDNA that encodes the 17-kD histone-like centromere antigen, CENP-A. Two domains are evident in the 140 aa CENP-A polypeptide: a unique NH2-terminal domain and a 93-amino acid COOH-terminal domain that shares 62% identity with nucleosomal core protein, histone H3. An epitope tagged derivative of CENP-A was faithfully targeted to centromeres when expressed in a variety of animal cells and this targeting activity was shown to reside in the histone-like COOH-terminal domain of CENP-A. These data clearly indicate that the assembly of centromeres is driven, at least in part, by the incorporation of a novel core histone into centromeric chromatin. ...
Centromeres are the specialized chromosomal sites necessary for poleward movement during mitosis and meiosis in eukaryotes. Commonly, a centromere is evident as a prominent constriction within the heterochromatin of each metaphase chromosome. The attachment to and movement of chromosomes along the spindle is mediated by the proteinaceous kinetochores, which form at the centromeres during cell division.. Despite this highly conserved function, centromeric DNA sequences are not conserved between organisms. For example, human centromeres consist of large blocks (200 kb to several megabases) of tandemly repeated 171-bp α-satellite (Willard, 1998), but the sequences can differ from those of apes on homologous chromosomes (Haaf and Willard, 1997). Similarly, Drosophila melanogaster centromeric regions contain blocks of 5- to 12-bp satellite repeats that do not appear to be shared by homologous centromeres of sibling species (Lohe and Brutlag, 1987).. Plant centromeric regions resemble their mammalian ...
Track indicating the location of the centromere sequences. Centromeres are specialized chromatin structures that are required for cell division. These genomic regions are normally defined by long tracts of tandem repeats, or satellite DNA, that contain a limited number of sequence differences to distinguish the linear order of repeat copies. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. Unlike all previous versions of the human reference assembly, where the centromere regions have been represented by a multi-megabase gap, GRCh38 incorporates centromere reference models that provide an initial genomic description derived from chromosome-assigned whole genome shotgun (WGS) read libraries of alpha satellite. Each reference model provides an approximation of the true array sequence organization. Although the long-range repeat ordering is not expected to represent the true organization, the submissions are expected to provide a ...
Track indicating the location of the centromere sequences. Centromeres are specialized chromatin structures that are required for cell division. These genomic regions are normally defined by long tracts of tandem repeats, or satellite DNA, that contain a limited number of sequence differences to distinguish the linear order of repeat copies. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. Unlike all previous versions of the human reference assembly, where the centromere regions have been represented by a multi-megabase gap, GRCh38 incorporates centromere reference models that provide an initial genomic description derived from chromosome-assigned whole genome shotgun (WGS) read libraries of alpha satellite. Each reference model provides an approximation of the true array sequence organization. Although the long-range repeat ordering is not expected to represent the true organization, the submissions are expected to provide a ...
Track indicating the location of the centromere sequences. Centromeres are specialized chromatin structures that are required for cell division. These genomic regions are normally defined by long tracts of tandem repeats, or satellite DNA, that contain a limited number of sequence differences to distinguish the linear order of repeat copies. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. Unlike all previous versions of the human reference assembly, where the centromere regions have been represented by a multi-megabase gap, GRCh38 incorporates centromere reference models that provide an initial genomic description derived from chromosome-assigned whole genome shotgun (WGS) read libraries of alpha satellite. Each reference model provides an approximation of the true array sequence organization. Although the long-range repeat ordering is not expected to represent the true organization, the submissions are expected to provide a ...
Track indicating the location of the centromere sequences. Centromeres are specialized chromatin structures that are required for cell division. These genomic regions are normally defined by long tracts of tandem repeats, or satellite DNA, that contain a limited number of sequence differences to distinguish the linear order of repeat copies. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. Unlike all previous versions of the human reference assembly, where the centromere regions have been represented by a multi-megabase gap, GRCh38 incorporates centromere reference models that provide an initial genomic description derived from chromosome-assigned whole genome shotgun (WGS) read libraries of alpha satellite. Each reference model provides an approximation of the true array sequence organization. Although the long-range repeat ordering is not expected to represent the true organization, the submissions are expected to provide a ...
This gene product is a highly conserved protein that facilitates centromere formation. It is a DNA-binding protein that is derived from transposases of the pogo DNA transposon family. It contains a helix-loop-helix DNA binding motif at the N-terminus, and a dimerization domain at the C-terminus. The DNA binding domain recognizes and binds a 17-bp sequence (CENP-B box) in the centromeric alpha satellite DNA. This protein is proposed to play an important role in the assembly of specific centromere structures in interphase nuclei and on mitotic chromosomes. It is also considered a major centromere autoantigen recognized by sera from patients with anti-centromere antibodies. [provided by RefSeq, Jul 2008 ...
The centromere-specific histone variant CENP-A (CID in Drosophila) is a structural and functional foundation for kinetochore formation and chromosome segregation. Here, we show that overexpressed CID is mislocalized into normally non-centromeric regions in Drosophila tissue culture cells and animals. Analysis of mitoses in living and fixed cells reveals that mitotic delays, anaphase bridges, chromosome fragmentation, and cell and organismal lethality are all direct consequences of CID mislocalization. In addition, proteins that are normally restricted to endogenous kinetochores assemble at a subset of ectopic CID incorporation regions. The presence of microtubule motors and binding proteins, spindle attachments, and aberrant chromosome morphologies demonstrate that these ectopic kinetochores are functional. We conclude that CID mislocalization promotes formation of ectopic centromeres and multicentric chromosomes, which causes chromosome missegregation, aneuploidy, and growth defects. Thus, CENP-A
DNA methylation is an epigenetically imposed mark of transcriptional repression that is essential for maintenance of chromatin structure and genomic stability. Genome-wide methylation patterns are mediated by the combined action of three DNA methyltransferases: DNMT1, DNMT3A and DNMT3B. Compelling links exist between DNMT3B and chromosome stability as emphasized by the mitotic defects that are a hallmark of ICF syndrome, a disease arising from germline mutations in DNMT3B. Centromeric and pericentromeric regions are essential for chromosome condensation and the fidelity of segregation. Centromere regions contain distinct epigenetic marks, including dense DNA hypermethylation, yet the mechanisms by which DNA methylation is targeted to these regions remains largely unknown. In the present study, we used a yeast two-hybrid screen and identified a novel interaction between DNMT3B and constitutive centromere protein CENP-C. CENP-C is itself essential for mitosis. We confirm this interaction in ...
Mitotic sister chromosomes individually attach to and harness the power of dynamic MT ends while maintaining an intercentromere elastic linkage that enables them to translocate jointly on the mitotic spindle and orient facing opposite spindle poles (Shelby et al., 1996). Robust MT attachments and proper orientation facing the opposite spindle poles maximizes the elastic pull on the sister centromeres and signals the cell that anaphase may safely commence. We have found that ectopically increasing the level of MCAK activity on centromeres decreases sister centromere tension, although not to the point that the spindle checkpoint is triggered. Conversely, decreased levels of MCAK on centromeres substantially increased tension across sister centromeres. Our data contradicts two other studies that suggest that the depletion of MCAK has no effect on tension (Ganem et al., 2005) or decreases tension (Kline-Smith et al., 2004). We believe that this discrepancy may be caused by the inclusion of ...
Our lab is interested in the epigenetic inheritance and organization of centromeres. The DNA sequence independent transmission of centromere identity through many cell generations is highly relevant for proper genome regulation and when perturbed can lead to genome instability and cellular malfunction. We use the fruit fly Drosophila melanogaster and human cells as a model organism to address the following questions: How is the epigenetic identity of centromeres regulated?. Centromeres are found at the primary constriction of chromosomes in mitosis where they remain connected before cell division. This structure is essential for an equivalent chromosomes distribution to the daughter cells. The centromere specific histone H3-variant CENP-AcenH3 is essential for kinetochore formation and centromere function. We have previously established a biosynthetic approach to target dCENP-AcenH3 to specific non-centromeric sequences such as the Lac Operator and follow the formation of functional ...
Stringent regulation of cellular levels of evolutionarily conserved centromeric histone H3 variant (CENP-A in humans, CID in flies, Cse4 in yeast) prevents its mislocalization to non-centromeric chromatin. Overexpression and mislocalization of CENP-A has been observed in cancers and leads to aneuploidy in yeast, flies, and human cells. Ubiquitin-mediated proteolysis of Cse4 by E3 ligases such as Psh1 and Sumo-Targeted Ubiquitin Ligase (STUbL) Slx5 prevent mislocalization of Cse4. Previously, we identified Siz1 and Siz2 as the major E3 ligases for sumoylation of Cse4. In this study, we have identified lysine 65 (K65) in Cse4 as a site that regulates sumoylation and ubiquitin-mediated proteolysis of Cse4 by Slx5. Strains expressing cse4 K65R exhibit reduced levels of sumoylated and ubiquitinated Cse4 in vivo. Furthermore, co-immunoprecipitation experiments reveal reduced interaction of cse4 K65R with Slx5, leading to increased stability and mislocalization of cse4 K65R under normal physiological ...
KAT7/HBO1/MYST2 Regulates CENP-A Chromatin Assembly by Antagonizing Suv39h1-Mediated Centromere InactivationKAT7/HBO1/MYST2 Regulates CENP-A Chromatin Assembly by Antagonizing Suv39h1-Mediated Centromere Inactivation ...
Author Summary The centromere is a chromosome domain essential for the correct partitioning of chromosomes during mitotic and meiotic cell divisions. The characterization of the centromeric proteins and their sequential assembly have been extensively studied in mammalian mitosis, since defective chromosome segregation is associated with birth defects and cancer. However, few studies have analyzed the centromere assembly during meiosis, a special cell division leading to the production of haploid gametes. Here, we analyze the sequence of loading of several centromeric and kinetochoric proteins during male mouse meiosis. We show that during both meiotic divisions, the proteins of the chromosomal passenger complex Borealin, INCENP, and Aurora-B load sequentially to the inner centromere before Shugoshin 2 and MCAK. The outer kinetochore proteins BubR1 and CENP-E are the last ones to be assembled. We also demonstrate, using a knockout mouse for Sgol2, that the inner centromeric protein Shugoshin 2 is
Inner centromere protein is a protein that in humans is encoded by the INCENP gene.[5][6][7] In mammalian cells, two broad groups of centromere-interacting proteins have been described: constitutively binding centromere proteins and passenger (or transiently interacting) proteins.[8] The constitutive proteins include CENPA (centromere protein A), CENPB, CENPC1, and CENPD. The term passenger proteins encompasses a broad collection of proteins that localize to the centromere during specific stages of the cell cycle.[9] These include CENPE; MCAK; KID; cytoplasmic dynein (e.g., DYNC1H1); CliPs (e.g. CLIP1); and CENPF/mitosin (CENPF). The inner centromere proteins (INCENPs),[5] the initial members of the passenger protein group, display a broad localization along chromosomes in the early stages of mitosis but gradually become concentrated at centromeres as the cell cycle progresses into mid-metaphase. During telophase, the proteins are located within the midbody in the intercellular bridge, where ...
This organism was chosen because it has epigenetically defined "regional centromeres" whose chromatin and protein compositions are similar to those of their human counterparts, to identify factors responsible for the replacement of histone H3 with CENP-A at centromeres.. In this report, the KAIST research group systematically analyzed the roles of the ATP-dependent chromatin-remodelers in the centromeric chromatin assembly of fission yeast as they serve as strong candidates for such factors ...
Centromeres are specialized chromosomal domains which are composed of centromeric DNA, often enriched in satellite repeats, and a large protein complex, the "kinetochore". Proper assembly of the kinetochore complex is a prerequisite for the correct segregation of chromosomes during mitotic and meiotic divisions and, consequently, for genome stability in all eukaryotic organisms. Deposition of the centromeric histone H3 variant CenH3 at the centromeric region is a prerequisite for correct assembly and function of the kinetochore complex in most eukaryotes. CenH3 deposition depends on cenH3 assembly factors, like KNL2 (Lermontova et al., 2013; Sandmann et al., 2017), chaperones (e.g. NASPSIM3, Le Goff et al., 2020), transcription of the centromeric repeats and the epigenetic status of centromeric chromatin. Specific manipulation of the CenH3 assembly factor KNL2 yielded double haploids in Arabidopsis thaliana (I. Lermontova, WO2017/067714). The production of double haploids enables a shortcut to ...
As the spindle fiber attachment region of the chromosome, the centromere has been investigated in a variety of contexts. Here, we will review current knowledge about this unique chromosomal region and its relevance for proper cell division, speciation, and disease. Understanding the three-dimensional organization of centromeres in normal and turner cells is just beginning to emerge. Multidisciplinary research will allow for new insights into its normal and aberrant nuclear organization and may allow for new therapeutic interventions that target events linked to centromere function and cell division ...
Following a close collaboration with the Chan lab and the demise of Simon Chan in the Summer of 2012, we have assimilated Chan lab researchers working on different aspects of centromeric function and its epigenetic determination. We are investigating the structural features, evolutionary constraints, and mechanisms that determine the interaction of centromeric histone H3 (CENH3) with the centromere and its instability in outcrosses resulting in parent-specific genome elimination. We are investigating the mechanisms of extreme chromosome fragmentation and reassembly that are associated to chromosome elimination. ...
Following a close collaboration with the Chan lab and the demise of Simon Chan in the Summer of 2012, we have assimilated Chan lab researchers working on different aspects of centromeric function and its epigenetic determination. We are investigating the structural features, evolutionary constraints, and mechanisms that determine the interaction of centromeric histone H3 (CENH3) with the centromere and its instability in outcrosses resulting in parent-specific genome elimination. In collaboration with the Korf lab, we are investigating the mechanisms of extreme chromosome fragmentation and reassembly that are associated to chromosome elimination. ...
Alignment of the centromere regions of all sixteen chromosomes. The regions include the Centromere DNA Elements I II and III (CDEI, CDEII and CDEIII). The conserved bases in all centromeres are marked in magenta. The regions with less conserved residues of CDEI and CDEIII are marked in green. The CDEII region which contains more than 90% AT residues has been left white. The multiple sequence alignment was created with PILEUP ...
GF ID Scm3 #=GF AC PF10384.8 #=GF DE Centromere protein Scm3 #=GF AU Mistry J, Wood V #=GF SE Pfam-B_19394 (release 21.0) #=GF GA 24.30 24.30; #=GF TC 24.60 24.40; #=GF NC 24.20 24.00; #=GF BM hmmbuild HMM.ann SEED.ann #=GF SM hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq #=GF TP Family #=GF RN [1] #=GF RM 17548816 #=GF RT Scm3, an essential Saccharomyces cerevisiae centromere protein #=GF RT required for G2/M progression and Cse4 localization. #=GF RA Stoler S, Rogers K, Weitze S, Morey L, Fitzgerald-Hayes M, Baker #=GF RA RE; #=GF RL Proc Natl Acad Sci U S A. 2007;104:10571-10576. #=GF RN [2] #=GF RM 17704645 #=GF RT Domain Architectures of the Scm3p Protein Provide Insights into #=GF RT Centromere Function and Evolution. #=GF RA Aravind L, Iyer LM, Wu C; #=GF RL Cell Cycle. 2007; [Epub ahead of print] #=GF RN [3] #=GF RM 19563746 #=GF RT Common ancestry of the CENP-A chaperones Scm3 and HJURP. #=GF RA Sanchez-Pulido L, Pidoux AL, Ponting CP, Allshire RC; #=GF RL Cell. 2009;137:1173-1174. ...
The localization of yeast centromeres and the 2-μm circle. Centromeres cluster close to the spindle pole body in late G1, but do not localize to the extreme nu
Centromeres are specialized chromatin structures that are required for cell division. The composition of these regions is complex, as they are made up of a series of tandem repeats that are arranged into nearly identical multi-megabase arrays. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. The Human Genome Project (HGP) employed a clone based strategy (largely BAC clones) to produce the reference assembly, but cloning centromere sequences generally requires special effort, and isnt readily applicable to all human centromeres (see Kouprina et al., 2003 for one such effort). With the recent widespread adoption of whole genome sequencing (WGS), there are clearly alpha-satellite sequences in the reads produced, but assembling these sequences into faithful representations of centromeres using standard techniques is impossible due to the repetitive nature of these sequences. In all previous versions of the human reference assembly, the ...
Centromeres are specialized chromatin structures that are required for cell division. The composition of these regions is complex, as they are made up of a series of tandem repeats that are arranged into nearly identical multi-megabase arrays. The size and repetitive nature of these regions mean they are typically not represented in reference assemblies. The Human Genome Project (HGP) employed a clone based strategy (largely BAC clones) to produce the reference assembly, but cloning centromere sequences generally requires special effort, and isnt readily applicable to all human centromeres (see Kouprina et al., 2003 for one such effort). With the recent widespread adoption of whole genome sequencing (WGS), there are clearly alpha-satellite sequences in the reads produced, but assembling these sequences into faithful representations of centromeres using standard techniques is impossible due to the repetitive nature of these sequences. In all previous versions of the human reference assembly, the ...
1. Steiner FA, Henikoff S. Diversity in the organization of centromeric chromatin. Current Opinion in Genetics & Development. 2015;31(0):28-35. doi: http://dx.doi.org/10.1016/j.gde.2015.03.010.. 2. Fukagawa T, Earnshaw William C. The Centromere: Chromatin Foundation for the Kinetochore Machinery. Developmental Cell. 30(5):496-508. doi: 10.1016/j.devcel.2014.08.016 25203206. 3. Cheeseman IM. The Kinetochore. Cold Spring Harbor Perspectives in Biology. 2014;6(7). doi: 10.1101/cshperspect.a015826. 4. Duro E, Marston AL. From equator to pole: splitting chromosomes in mitosis and meiosis. Genes & Development. 2015;29(2):109-22. doi: 10.1101/gad.255554.114. 5. Allshire RC, Karpen GH. Epigenetic regulation of centromeric chromatin: old dogs, new tricks? Nat Rev Genet. 2008;9(12):923-37. doi: 10.1038/nrg2466 19002142. 6. Sekulic N, Black BE. Molecular underpinnings of centromere identity and maintenance. Trends in Biochemical Sciences. 37(6):220-9. doi: 10.1016/j.tibs.2012.01.003 22410197. 7. Palmer DK, ...
Our research program is focused on the important basic question of how chromosomes are segregated during cell division to ensure the complete and accurate inheritance of the genome. Chromosome instability is a hallmark of cancer and can drive tumorigenesis. Therefore, how centromere specification is controlled is a basic biological question with great therapeutic potential. Centromeres are specified by the incorporation of a histone variant CENP-A, and stable inheritance of this locus is control...[Read full text]Our research program is focused on the important basic question of how chromosomes are segregated during cell division to ensure the complete and accurate inheritance of the genome. Chromosome instability is a hallmark of cancer and can drive tumorigenesis. Therefore, how centromere specification is controlled is a basic biological question with great therapeutic potential. Centromeres are specified by the incorporation of a histone variant CENP-A, and stable inheritance of this locus ...
TY - JOUR. T1 - Probing the architecture of a simple kinetochore using DNA-protein crosslinking. AU - Espelin, Christopher W.. AU - Kaplan, Kenneth B.. AU - Sorger, Peter K.. PY - 1997/12/15. Y1 - 1997/12/15. N2 - In budding yeast, accurate chromosome segregation requires that one and only one kinetochore assemble per chromosome. In this paper, we report the use of DNA-protein crosslinking and nondenaturing gel analysis to study the structure of CBF3, a four-protein complex that binds to the essential CDEIII region of Saccharomyces cerevisiae centromeres. We find that three subunits of CBF3 are in direct contact with CDEIII over a region of DNA that spans 80 bp. A highly asymmetric core complex containing p58(CTF13) p64(CEP3) and p110(NDC10) in direct contact with DNA forms at the genetically defined center of CDEIII. This core complex spans ~56 bp of CEN3. An extended complex comprising the core complex and additional DNA-bound p110(NDC10) also forms. It spans ~80 bp of DNA. CBF3 makes ...
In this diagram o a duplicatit chromosome, (2) identifies the centromere-the region that jyns the twa sister chromatids, or each hauf o the chromosome. In prophase o mitosis, specialised regions on centromeres cried kinetochores attach chromosomes tae spindle fibers ...
The centromere is the structure at the center of every X-shaped chromosome, where cells attached the long, thin spindles that pull the two copies of DNA apart during cell division. A new technique makes it much easier to study centromeres, and look for links to conditions such as Down syndrome.
Centromere B Ab ELISA Kit is an indirect solid phase enzyme immunoassay for the quantitative measurement of IgG class autoantibodies against Centromere B in human serum or plasma. (KA1275) - Products - Abnova
Chromosomes can be classified based on the following except ____. a) centromere location b) centromere size c) number of centromeres d) centromere duration
Article source: http://theworldseeds.cn/index.php?p=152804 (Translated by Google Translate) The centromere and its surroundings are the fastest-evolving and…
CENPP is a subunit of a CENPH (MIM 605607)-CENPI (MIM 300065)-associated centromeric complex that targets CENPA (MIM;117139) to centromeres and is required for proper kinetochore function and mitotic progression (Okada et al., 2006;(PubMed 16622420 ...
We study the spectrum and mechanisms of telomere function. Recent highlights include the discovery of a mode by which telomerase-negative cells can use generic heterochromatin to protect ends. We have also expanded the telomeric repertoire, finding that telomeres control meiotic spindle formation and centromere assembly; these principles apply to proliferating cells as well, as centromeres control the decision to mount mitotic spindle assembly.. Keywords: Telomeres / Centromeres / DNA damage response / fission yeast / meiosis / chromatin & nuclear organization. Subject area(s): Cell Cycle , Chromatin & Transcription , Genome Stability & Dynamics. ...
Read "Recognition of A. thaliana centromeres by heterologous CENH3 requires high similarity to the endogenous protein, Plant Molecular Biology" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
We next studied the subcellular localization of endogenous Snap29 in S2 cells by immunofluorescence. While the protein is not present in the nucleus of cells in interphase, we discovered a pool of Snap29 puncta associated with chromosomes of cells in mitosis, which are positive for phospho‐histone 3 (pH3), a marker of the centromeric chromatin of dividing cells (Fig 1B). At metaphase, such pool colocalizes with Cid (Drosophila CENPA), a inner KT component, but not with Incenp, a centromeric chromatin protein (Fig 1C), indicating that Snap29 is present at KTs during mitosis. By super‐resolution confocal microscopy, Snap29 appears to localize distal to CenpC, with connects the inner and other part of the KT (Fig 1D, inset). In contrast, Snap29 localizes proximal to Spc105R (Fig 1E, inset). These data reveal that Snap29 resides in the proximal part of the outer KT in mitotic cells.. Formation of the outer KT in Drosophila is concomitant with nuclear envelope fenestration, nuclear lamina ...
We next studied the subcellular localization of endogenous Snap29 in S2 cells by immunofluorescence. While the protein is not present in the nucleus of cells in interphase, we discovered a pool of Snap29 puncta associated with chromosomes of cells in mitosis, which are positive for phospho‐histone 3 (pH3), a marker of the centromeric chromatin of dividing cells (Fig 1B). At metaphase, such pool colocalizes with Cid (Drosophila CENPA), a inner KT component, but not with Incenp, a centromeric chromatin protein (Fig 1C), indicating that Snap29 is present at KTs during mitosis. By super‐resolution confocal microscopy, Snap29 appears to localize distal to CenpC, with connects the inner and other part of the KT (Fig 1D, inset). In contrast, Snap29 localizes proximal to Spc105R (Fig 1E, inset). These data reveal that Snap29 resides in the proximal part of the outer KT in mitotic cells.. Formation of the outer KT in Drosophila is concomitant with nuclear envelope fenestration, nuclear lamina ...
The chromosome band track represents the approximate location of bands seen on Giemsa-stained chromosomes. Chromosomes are displayed in the browser with the short arm first. Cytologically identified bands on the chromosome are numbered outward from the centromere on the short (p) and long (q) arms. At low resolution, bands are classified using the nomenclature [chromosome][arm][band], where band is a single digit. Examples of bands on chromosome 3 include 3p2, 3p1, cen, 3q1, and 3q2. At a finer resolution, some of the bands are subdivided into sub-bands, adding a second digit to the band number, e.g. 3p26. This resolution produces about 500 bands. A final subdivision into a total of 862 sub-bands is made by adding a period and another digit to the band, resulting in 3p26.3, 3p26.2, etc. ...
The chromosome band track represents the approximate location of bands seen on Giemsa-stained chromosomes. Chromosomes are displayed in the browser with the short arm first. Cytologically identified bands on the chromosome are numbered outward from the centromere on the short (p) and long (q) arms. At low resolution, bands are classified using the nomenclature [chromosome][arm][band], where band is a single digit. Examples of bands on chromosome 3 include 3p2, 3p1, cen, 3q1, and 3q2. At a finer resolution, some of the bands are subdivided into sub-bands, adding a second digit to the band number, e.g. 3p26. This resolution produces about 500 bands. A final subdivision into a total of 862 sub-bands is made by adding a period and another digit to the band, resulting in 3p26.3, 3p26.2, etc. ...
Centromeres arent circles like theyre drawn in the books, theyre just repetitie DNA sequences, and they look just like any other part of the chromosome... like DNA. And im guessing they get separated when the centrioles pull each chromosomes chromatid away in opposite directions through the nuclear spindles (which are like strings that hook to each chromatid ...
Bekijk Stockfoto van Pair Of Chromosomes Connected By A Centromere Sem. Ga voor hoogwaardige fotos met een hoge resolutie naar Getty Images.
DNA-binding component of the FA core complex involved in DNA damage repair and genome maintenance. Recruited to forks stalled by DNA interstrand cross-links, and required for cellular resistance to such lesions. Component of the heterotetrameric CENP-T-W-S-X complex that binds and supercoils DNA, and plays an important role in kinetochore assembly. Component of the APITD1/CENPS complex that is essential for the stable assembly of the outer kinetochore. Plays an important role in mitotic progression and chromosome segregation ...
Wow, I count 14 question marks in one post. Is that a record?. Ill try to hit as many of the question marks as possible.. 1. So wouldnt the first human (with 46) have significant trouble reproducing? Not necessarily. Research has been performed to investigate just this question and found that fertility is effected only minimally. Essentially, it turns out that some centromeres are better at attracting the kinetochore machinery than others and thus outcompete the neighboring centromere for resources [a]. Thus, even in the case of a fusion, only one centromere will remain active.. 2. Could he or she reproduce with an ape mate? No. Nor would they likely be interested in doing so - any more than you are interested in mating with a gorilla. When a chromosomal fusion occurs in one individual human, they would look no different than any other human. All the same genes are still there, being expressed the same way. When the fusion of chromosomes 12 and 13 occurred in the human lineage, nobody would ...
Wow, I count 14 question marks in one post. Is that a record?. Ill try to hit as many of the question marks as possible.. 1. So wouldnt the first human (with 46) have significant trouble reproducing? Not necessarily. Research has been performed to investigate just this question and found that fertility is effected only minimally. Essentially, it turns out that some centromeres are better at attracting the kinetochore machinery than others and thus outcompete the neighboring centromere for resources [a]. Thus, even in the case of a fusion, only one centromere will remain active.. 2. Could he or she reproduce with an ape mate? No. Nor would they likely be interested in doing so - any more than you are interested in mating with a gorilla. When a chromosomal fusion occurs in one individual human, they would look no different than any other human. All the same genes are still there, being expressed the same way. When the fusion of chromosomes 12 and 13 occurred in the human lineage, nobody would ...
Typically the chromosome also contains a selection marker such as TRP1, Lys2 or Ura3. Minimal size for a YAC is between 50kb and 100kb, while maximum sizes are 1Mb to 3Mb. A common tool for constructing YACs is a shuttle plasmid such as pYAC4 which replicates in E. coli, has a multiple cloning site, and a pair of telomeres which can be cleaved to form a linear fragment. Available as an E.coli plasmid ATCC 67379, sequence at U01086. There are two common centromere sequences, CEN4 and CEN6. CEN4 is found in most yeast centromere-containiing vectors, such as pYAC4. These vectors typically use ARS1 sequences. The pRS313- pRS316 plasmids use the CEN6 + ARSH4 cassette (Sikorski89). ...
During meiosis, crossover recombination is essential to link homologous chromosomes and drive 22 faithful chromosome segregation. Crossover recombination is non-random across the genome, 23 and centromere-proximal crossovers are associated with an increased risk of aneuploidy, 24 including Trisomy 21 in humans. Here, we identify the conserved Ctf19/CCAN kinetochore sub- 25 complex as a major factor that minimizes potentially deleterious centromere-proximal crossovers 26 in budding yeast. We uncover multi-layered suppression of pericentromeric recombination by the 27 ...
This volume focuses on the structural aspects of cell division, ranging from nuclear envelope breakdown to cytokinesis and partitioning of the cytoplasm. It examines spindle assembly and chromosome behavior in mitosis and meiosis, centromere and kinetochore structure and regulation, telomeres, the role of centrosomes, and mechanisms by which overall regulation is achieved.
This volume focuses on the structural aspects of cell division, ranging from nuclear envelope breakdown to cytokinesis and partitioning of the cytoplasm. It examines spindle assembly and chromosome behaviour in mitosis and meiosis, centromere and kinetochore structure and regulation, telomeres, the role of centrosomes, and mechanisms by which overall regulation is achieved. The up-to-date reviews of each topic provide perspectives on recent important findings. Each chapter presents models and new ideas that accommodate available information ...
中節,人體部位名。手足指(趾)的第二節。手足大指(趾)無此節。. 染色體著絲粒(centromere),又稱中節,主要作用是使複製的染色體在有絲分裂和減數分裂中可均等地分配到子細胞中。在很多高等真核生物中,著絲粒看起來像是在染色體一個點上的濃縮區域,這個區域包含著絲點(希臘語kínesis 運動;chóros 部位),又稱主縊痕(primary constriction)。. 著絲粒(染色體的主縊痕)為染色質的結構,將染色體分成二臂,在細胞分裂前期和中期,把兩個姐妹染色單體連在一起,到後期兩個染色單體的著絲粒分開。著絲粒兩側各有一個由蛋白質構成的3層盤狀特化結構,為非染色體性質物質的附加物,稱為著絲點。. 在大部分真核生物中每個紡錘絲附著在不同的著絲粒上。如啤酒酵母(Saccharomyces ...
Evolutionarily conserved Cse4, the centromeric histone H3 variant (CENP-A in humans) and its chaperone Scm3 (HJURP in humans) which are essential for chromosome...
the spindle fibers enter the nuclear regioin attaching to a complex system of fibers on the centromere known as the kinetochore. after attachment the spindle fibers align the centromeres along an equatrorial region in the nucleus known as the metaphase plate so that the arms of the chromosome point towards the poles of the cell ...
Mitosis Vocabulary. Mitosis -the process of cell division including division of the nucleus.. Cancer -disorder caused when cells lose the ability to control growth and continue to divide.. Interphase -part of the cell cycle when the cell is not dividing. G1 -phase of the cell cycle after cell division, growth and day to day life of a cell.. S Phase -Replication or synthesis of DNA and associated proteins that happens before cells divide.. G2 -Phase of the cell cycle when cells prepare for cell division by making more organelles and cytoplasm.. Diffusion - How most water soluble materials get into a cell. process by which molecules tend to move from an area of higher concentration to an area of lower concentration.. Chromosome -Thread like structure with in the nucleus containing genetic information. Made of DNA coiled around proteins.. Chromatid -half of a duplicated chromosome. One of two "sister" parts, makes half of the "X"(middle is Centromere). Centromere -area where sister chromatids of a ...
Blue horizontal bar: chromosome sequence. Blue/green fragments: individual clone and WGS components in the assembly tiling path. Purple bars: assembly-assembly alignments. The p- and q- arms, as well as the location of the centromere and adjacent heterochromatin gaps are marked. Note: in GRCh38, the centromere gap was replaced with sequence. The vertical bars through the alignments highlight sequence from the q-arm of GRCh37 chr. 9 that is now found on the p-arm of GRCh38 ...
Definition: In eukaryotes, a DNA molecule that contains genes in linear order to which numerous proteins are bound and that has a telomere at each end and a centromeres. In prokaryotes, the DNA is associated with fewer proteins, lacks telomers and a centromeres, and is often circular. In viruses, the chromosome is DNA or RNA, single strained or double-stranded, linear or circular, and often free of bound proteins. Source: Essential Genetics: A Genomics Perspective (2006) 4th Ed. ...
(2015) Barth et al. Data in Brief. Centromeres of higher eukaryotes are epigenetically defined by the centromere specific histone H3 variant CENP-ACID. CENP-ACID builds the foundation for the assembly of a large network of proteins. In contrast to mammalian systems, the protein composition of Dro...
Early this year I attended a dermatologist for a skin problem. While there she gave a me a list of bloods to get done. She diagnosed my skin problem and I thought that was it. I misplaced the results, and have only recently sent them back. The ANA test came back negative. However, the bloods also detected the presence of the following antibodies; U1-RNP, SS-A/RO , SS-B/LA, Centromere B , SCL-70 , Fibrillarin, pm-scl and Ds-dna. Could the ANA result be wrong because the blood test detected these antibodies? Im scared about the Scl-70 and Centromere B antibodies, does that mean I am very likely to develop Scleroderma? The only symptom that I currently have is Raynauds. I had this for a good few years now, but never thought anything of it ...
Booth DG, Beckett AJ, Molina O, Samejima I, Masumoto H, Kouprina N, Larionov V, Prior IA, Earnshaw WC. 3D-CLEM Reveals that a Major Portion of Mitotic Chromosomes Is Not Chromatin. Mol Cell. 2016 Nov 17;64(4):790-802. doi: 10.1016/j.molcel.2016.10.009. Epub 2016 Nov 10. PMID: 27840028; FREE ARTICLE. Ohzeki J, Shono N, Otake K, Martins NM, Kugou K, Kimura H, Nagase T, Larionov V, Earnshaw WC, Masumoto H. KAT7/HBO1/MYST2 Regulates CENP-A Chromatin Assembly by Antagonizing Suv39h1-Mediated Centromere Inactivation. Dev Cell. 2016 Jun 6;37(5):413-27. doi: 10.1016/j.devcel.2016.05.006. PMID: 27270040; FREE ARTICLE. Ohta S, Montaño-Gutierrez LF, de Lima Alves F, Ogawa H, Toramoto I, Sato N, Morrison CG, Takeda S, Hudson DF, Rappsilber J, Earnshaw WC. Proteomics Analysis with a Nano Random Forest Approach Reveals Novel Functional Interactions Regulated by SMC Complexes on Mitotic Chromosomes. Mol Cell Proteomics. 2016 Aug;15(8):2802-18. doi: 10.1074/mcp.M116.057885. Epub 2016 May 26. PMID: 27231315; ...
Chromosomes are only visible when chromatin condesnes prior to cell divison. This is after each DNA molecule has made an exact copy of itself. The two copies of a chromosome are called sister chromatids. They lie parallel along their length joined at a region called the centromere. Pairs of matching chromosomes are called homologous pairs.. ...
Adjectives are words that describe or modify another person or thing in the sentence. That means, despite my birthday, Im actually the least Irish. Whether youre the first-born, middle child, or youngest makes little difference, as parents tend to favour the kid that is most present in their lives. nephew - somebodys brothers or sisters son; your husbands or wifes brothers or sisters son. During mitosis, all the chromosomes in a cell are copied, line up at the metaphase plate, split apart at the centromere, and segregate into two new (but genetically identical) cells. Your mother (or father) has bought you an ugly sweater for the holidays. Both your breasts should be the same size. My sister wants my mom on medication because my mom yells a lot and is traumatized and stressed from my dads death. a girl or woman who has the same parents as another person: 2. CAS-003 Quiz Guide - CAS-003 Exam Prep & CAS-003 Test Braindumps, No matter what levels or degrees you knowledge are for now, you ...
In the cell cycle DNA synthesis occurs during ________________. At the beginning of prophase _______________ condenses and chromosomes become visible. The end of prophase is characterized by the breakdown of the __________________________. The chromosomes become attached to the equator of the ______________ during ______________________. At anaphase the chromosome splits at the centromere and one copy heads towards each pole of the spindle. The final phase is called _______________ and it involves the formation of two new separate nuclei. In animal cells this phase is followed by ___________________. ...
Polyclonal antibody for BUB3 detection. Host: Rabbit.Size: 100μg/vial. Tested applications: IHC-P. Reactive species: Human. BUB3 information: Molecular Weight: 37155 MW; Subcellular Localization: Nucleus. Chromosome, centromere, kinetochore . Starts to lo
Dr. Patrick Heun and his group of researchers at the Max Planck Institute (MPI) of Immunobiology and Epigenetics in Freiburg are working on elucidating the spatial organisation of cell nuclei and how the structure of chromosomes is passed on to daughter cells during the division of cells. The researchers have come up with clear proof that the formation of centromeres depends on a single molecule.
I have localized scleroderma morphea. I have the results of my blood work back, most is pretty good. I have a question about one test, the centromere antibo...
BLOT kit for the detection of specific IgG antibodies to the recombinant extractable nuclear antigens and centromere B in human serum or plasma.
The Bioconductor-mirror/GWASTools package contains the following man pages: alleleFrequency allequal anomDetectBAF anomDetectLOH anomIdentifyLowQuality anomSegStats apartSnpSelection assocCoxPH assocRegression BAFfromClusterMeans BAFfromGenotypes batchTest centromeres chromIntensityPlot convertNcdfGds createDataFile defunct duplicateDiscordance duplicateDiscordanceAcrossDatasets duplicateDiscordanceProbability exactHWE findBAFvariance GdsGenotypeReader-class GdsIntensityReader-class GdsReader-class gdsSubset genoClusterPlot GenotypeData-class genotypeToCharacter getobj getVariable GWASTools-package hetByScanChrom hetBySnpSex HLA ibdPlot imputedDosageFile IntensityData-class intensityOutliersPlot manhattanPlot MatrixGenotypeReader-class meanIntensityByScanChrom mendelErr mendelList missingGenotypeByScanChrom missingGenotypeBySnpSex NcdfGenotypeReader-class NcdfIntensityReader-class NcdfReader-class pasteSorted pcaSnpFilters pedigreeCheck pedigreeDeleteDuplicates pedigreeMaxUnrelated
MT-independent binding of Bik1 to the kinetochore. (A) Bik1 can be cross-linked to CEN DNA in the absence of MTs. Chip with strains bearing the indicated Bik1 d
Hello, I was wondering if anyone can recommend good study material for the CEN exam. I understand that the exam has a high first-time fail rate. I want to pass the first time! Thanks, David
We report the interaction between a human centromere antigen and an alphoid DNA, a human centromeric satellite DNA, which consists of 170-bp repeating units. A cloned alphoid DNA fragment incubated with a HeLa cell nuclear extract is selectively immunoprecipitated by the anticentromere sera from scleroderma patients. Immunoprecipitation of the DNA made by primer extension defines the 17-bp segment on the alphoid DNA that is required for formation of DNA-antigen complex. On the other hand, when proteins bound to the biotinylated alphoid DNA carrying the 17-bp motif are recovered by streptavidin agarose and immunoblotted, the 80-kD centromere antigen (CENP-B) is detected. DNA binding experiments for proteins immunoprecipitated with anticentromere serum, separated by gel electrophoresis, and transferred to a membrane strongly suggest that the 80-kD antigen specifically binds to the DNA fragment with the 17-bp motif. The 17-bp motif is termed the "CENP-B box." Alphoid monomers with the CENP-B box ...
The organization, evolution and function of eukaryotic centromeres represent a deficiency in our understanding of genome biology. The discovery of human clinical neocentromeres and ENCs has further complicated, on one hand, our understanding of the centromere. On the other hand, neocentromeres and ENCs have allowed an initial dissection of centromere complexity. They have made evident, for instance, its epigenetic nature. The ENC analysis we have accomplished in the present study has contributed to the identification of factors that, very likely, play a crucial role in ENC progression and fixation in the population. We have provided strong evidence that the pericentromeric duplication activity is an intrinsic property of ENCs. This conclusion was mainly supported by FISH experiments using species-specific BAC clones that detected SDs around the centromere in almost all studied ENCs. A deep restructuring was particularly evident in MMU17 (human 13) and MMU2 (human 3). The latter ENC showed a ...
In order to define a functional human centromere sequence, an artificial chromosome was constructed as a reproducible DNA molecule. Mammalian telomere repeats and a selectable marker were introduced into yeast artificial chromosomes (YACs) containing alphoid DNA from the centromere region of human c …
Chicken (Gallus gallus domesticus, GGA) and Japanese quail (Coturnix coturnix japonica, CCO) karyotypes are very similar. They have identical chromosome number (2n = 78) and show a high degree of synt
We describe a process in meiotic cells of budding yeast in which chromosomes become joined together in pairs at their centromeres independent of chromosomal homology. These centromeric interactions depend on the synaptonemal complex component Zip1. During meiosis in wild-type diploids, centromere couples are initially nonhomologous and then undergo switching until all couples involve homologs. This transition to homologous coupling depends on Spo11, a protein required for the initiation of meiotic recombination. Regions of synaptonemal complex assembled early in meiosis are often centromere-associated. We propose that centromere coupling facilitates homolog pairing and promotes synapsis initiation. ...
P>We conducted genome-wide mapping of cytosine methylation using methylcytosine immunoprecipitation combined with Illumina sequencing. The chromosomal distribution pattern of methylated DNA is similar to the heterochromatin distribution pattern on rice chromosomes. The DNA methylation patterns of rice genes are similar to those in Arabidopsis thaliana, including distinct methylation patterns asssociated with gene bodies and promoters. The DNA sequences in the core domains of rice Cen4, Cen5 and Cen8 showed elevated methylation levels compared with sequences in the pericentromeric regions. In addition, elevated methylation levels were associated with the DNA sequences in the CENH3-binding subdomains, compared with the sequences in the flanking H3 subdomains. In contrast, the centromeric domain of Cen11, which is composed exclusively of centromeric satellite DNA, is hypomethylated compared with the pericentromeric domains. Thus, the DNA sequences associated with functional centromeres can be ...
Constitutive heterochromatin, mainly formed at the gene-poor regions of pericentromeres, is believed to ensure a condensed and transcriptionally inert chromatin conformation. Pericentromeres consist of repetitive tandem satellite repeats and are crucial chromosomal elements that are responsible for accurate chromosome segregation in mitosis. The repeat sequences are not conserved and can greatly vary between different organisms, suggesting that pericentromeric functions might be controlled epigenetically. In this review, we will discuss how constitutive heterochromatin is formed and maintained at pericentromeres in order to ensure their integrity. We will describe the biogenesis and the function of main epigenetic pathways that are involved and how they are interconnected. Interestingly, recent findings suggest that alternative pathways could substitute for well-established pathways when disrupted, suggesting that constitutive heterochromatin harbors much more plasticity than previously assumed. In
The essential histone H3 variant Cse4 plays a crucial role at the centromere in S. cerevisiae, where it replaces histone H3 in that it assembles centromere specific (Cse4-H4)2 tetrameres. We found in our study that the histone H3 variant was able to interact over its unique N-Terminus with two subunits of the histone acetyltransferase complex SAS-I: Sas2 and Sas4. Mutations within the acetyl-CoA binding site (HAT domain) or the zink-finger of Sas2 disrupted the binding to Cse4, although an indirect interaction was found with co-immunoprecipitation experiments. Additionally, the N-terminus of Cse4 interacted with Cac1, the largest subunit of the chromatin assembly factor CAF-I and Asf1 - two histone chaperones that assemble histones H3 and H4 into nucleosomes. Our findings further suggest a role of Cac1 independent of Cac2 and Cac3 as no binding to Cse4 could be detected. A role for Sas2 at the centromere was further confirmed in that a sas2 deletion (sas2 delta) disrupted the binding of Cse4 to ...
Model for heterochromatin assembly and spreading at S. pombecentromeric outer repeats. Heterochromatic centromere sequences (yellow arrow) are transcribed by RNA Polymerase II. These centromere transcripts are targeted by RITS via siRNA loaded Ago1. Association of RITS with centromere heterochromatin is strengthened by binding of Chp1 to H3mK9. RITS activity can recruit both CLRC, via interactions with Stc1, and RDRC resulting in spreading of H3mK9 and amplification of siRNAs, respectively (see text for details). dsRNA generated either by bi-directional transcription from centromere promoters (black arrows) or by RDRC activity is recognized and processed by Dicer (Dcr1). The resulting centromere siRNAs are then loaded onto Ago1 first in the ARC complex and then in RITS ...
Kelly Dawe. Distinguished Research Professor What are plant centromeres made of? How are they inherited, what proteins interact with them, and how do they evolve? What are centromeres? For over twelve years our lab has been working through the answers to these questions.lab was founded with the goal of understanding plant kinetochores. We have made good progress mostly by making specific antisera and combining the power of maize cytogenetics with 3D light microscopy. Much of our effort has focused on the inner kinetochore proteins Centromeric Histone H3 (CENH3) and Centromere Protein C (CENP-C), as well as MAD2, a spindle checkpoint protein that localizes to the outer kinetochore. We have worked on a serine-50 phosphorylated form of CENH3, NDC80, and several other kinetochore proteins. Our long-term goal is to identify the complete collection of inner kinetochore proteins, and to develop a model for how these proteins are organized. We intend to pursue the tried-and-true method of identifying ...
The centromere is a special region of a chromosome, usually near the middle. It is where the two identical sister chromatids stay in contact as the chromosome attaches to the spindle in mitosis. The region contains specific types of DNA, which are tandem repetitive sequences (satellite DNA). These sequences bind specific proteins called "cen"-proteins. During mitosis the centromeres can be seen during the metaphase stage as a constriction at the chromosome. At this centromeric constriction the two halves of the chromosome, the sister chromatids, are held together until late metaphase. ...
The centromere is a special region of a chromosome, usually near the middle. It is where the two identical sister chromatids stay in contact as the chromosome attaches to the spindle in mitosis. The region contains specific types of DNA, which are tandem repetitive sequences (satellite DNA). These sequences bind specific proteins called "cen"-proteins. During mitosis the centromeres can be seen during the metaphase stage as a constriction at the chromosome. At this centromeric constriction the two halves of the chromosome, the sister chromatids, are held together until late metaphase. ...
Two ZMPSTE24 mutations in the yeast to complement the (S. cerevisiae) mating defect STE24 and Ras-converting enzyme 1 (RCE1; another prenylprotein-specific endoprotease) genes [§§] (farnesylated protein-converting enzymes 1 and 2) is a significant component of the rice centromere antigens lamin A/C and B1 identified (in non-transgenic plants that go awry↩ (centromere) in cancer), the Ras…
Users of the eukaryotic phylum Apicomplexa are the cause of important human being diseases including malaria toxoplasmosis and cryptosporidiosis. transgenic parasite lines expressing epitope-tagged centromeric H3 variant CenH3 we determine the centromeres of chromosomes by hybridization of chromatin immunoprecipitations to genome-wide microarrays (ChIP-chip). We demonstrate that centromere attachment to the centrocone persists throughout the parasite cell cycle and that centromeres localize to a single apical region within the nucleus. Centromere sequestration provides a mechanism for Meloxicam (Mobic) the organization of the nucleus and the maintenance of genome integrity. tachyzoites featuring the simplest form endodyogeny bud into two daughters after each round of DNA replication (3). the causative agent of malaria divides by schizogony whereby the cell proceeds through several rounds of DNA replication and mitosis before the right now multinucleate schizont gives rise to multiple zoites at ...
Cnp1, Mis6, and Mis13 are required for localizing condensin at the kinetochore. (A) Cells cultured at 26°C in EMM2 were observed for the colocalization of Cnd1-GFP with Mis12-RFP, a centromere/kinetochore protein. The numbers in the right panels indicate time in minutes. The enlarged images of Cnd1-GFP (left), Mis12-RFP (middle), and the merged images (right) at 13 min are shown in the insets. (B) Cut14-GFP and Sad1-RFP were observed in the wild-type, mis6-302, cnp1-1, mis13-1, mis16-53, and mis18-262 mutants cultured at 26°C and were shifted to 36°C for 8 h. (C) Chromosomally integrated Cnp1/CENP-A-GFP expressed under the native promoter was observed in the wild-type and cut14-208 mutant cultured at 36°C for 2 h. (D) A ChIP assay was performed using extracts of block-released nda3-311 mutant that expressed Cut14-Flag. The probes were from the central centromere, cnt1 (c10, c9, and c7.5), imr1 (c4 and c1), the outer centromere dg, and the noncentromeric lys1+. WCE, whole cell extract; IP, ...
Saffery, Richard, Sumer, Huseyin, Hassan, Sara, Wong, Lee H, Craig, Jeffrey M, Todokoro, Kazuo, Anderson, Melissa, Stafford, Angela and Choo, KH Andy 2003, Transcription within a functional human centromere, Molecular cell, vol. 12, no. 2, pp. 509-516, doi: 10.1016/S1097-2765(03)00279-X. ...
Sigma-Aldrich offers abstracts and full-text articles by [Mourad Sanhaji, Andreas Ritter, Hannah R Belsham, Claire T Friel, Susanne Roth, Frank Louwen, Juping Yuan].
A DNA-binding protein that interacts with a 17-base pair sequence known as the CENP-B box motif. The protein is localized constitutively to the CENTROMERE and plays an important role in its maintenance ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
"Entrez Gene: INCENP inner centromere protein antigens 135/155kDa".. *^ Choo, K. H. Andy (1997). The centromere. Oxford [ ... In mammalian cells, two broad groups of centromere-interacting proteins have been described: constitutively binding centromere ... Inner centromere protein is a protein that in humans is encoded by the INCENP gene.[5][6][7] ... The term 'passenger proteins' encompasses a broad collection of proteins that localize to the centromere during specific stages ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
Telomeres and centromeres typically contain few genes but are important for the function and stability of chromosomes.[58][94] ... "The role of heterochromatin in centromere function". Philosophical Transactions of the Royal Society of London. Series B, ...
The two chromatids are joined at the centromere. Gene transcription ceases during prophase and does not resume until late ... Microtubules project from opposite ends of the cell, attach to the centromeres, and align the chromosomes centrally within the ... Chromosome duplication results in two identical sister chromatids bound together by cohesin proteins at the centromere. ... A kinetochore is a proteinaceous microtubule-binding structure that forms on the chromosomal centromere during late prophase.[ ...
Fusion of ancestral chromosomes left distinctive remnants of telomeres, and a vestigial centromere. As other non-human extant ... Attention is paid to their length, the position of the centromeres, banding pattern, any differences between the sex ... "Chromatin Ring Formation at Plant Centromeres". Front Plant Sci. 7: 28. doi:10.3389/fpls.2016.00028. PMC 4753331. PMID ...
... acen Centromere. var: Variable region; stalk: Stalk. ...
FRT sites have been inserted transgenically near the centromere of each chromosome arm of Drosophila melanogaster. The FLP gene ... The recombination needs to occur between the centromere the adjacent gene. This gives an appearance of yellow patches on the ...
... inversions and centromere repositioning.[18] Przewalski's horse is known to have the highest diploid chromosome number among ... "Phylogeny of Horse Chromosome 5q in the Genus Equus and Centromere Repositioning". Cytogenetic and Genome Research. 126: 165- ...
Robertsonian translocation: An entire chromosome has attached to another at the centromere - in humans these only occur with ... Isochromosome: Formed by the mirror image copy of a chromosome segment including the centromere. ...
2) Centromere - the point where the two chromatids touch. (3) Short arm. (4) Long arm. ... The chromatids are joined at the centromere. ...
... acen Centromere. var: Variable region; stalk: Stalk. Lee, Victor Robert (2013-01-15). Performance Anomalies: A Novel. Perimeter ...
... acen Centromere. var: Variable region; stalk: Stalk. Mainardi PC, Perfumo C, Cali A, Coucourde G, Pastore G, Cavani S, Zara F, ...
... acen Centromere. var: Variable region; stalk: Stalk. General references: Bittel DC, Butler MG (2005). "Prader-Willi syndrome: ...
... acen Centromere. var: Variable region; stalk: Stalk. Gilbert F (2000). "Disease genes and chromosomes: disease maps of the ...
Normally a chromosome has just one centromere, but in chromosome 2 there are remnants of a second centromere in the q21.3-q22.1 ... acen Centromere. var: Variable region; stalk: Stalk. National Institutes of Health. "Chromosome 2". Genetics Home Reference. ...
... acen Centromere. var: Variable region; stalk: Stalk. "Chromosome 6 Project - Chromosome 6 Research Project". Chromosome 6 ...
The centromere of chromosome 14 is positioned approximately at position 17.2 Mbp. The following are some of the gene count ... acen Centromere. var: Variable region; stalk: Stalk. Campo E (2003). "Genetic and molecular genetic studies in the diagnosis of ...
... acen Centromere. var: Variable region; stalk: Stalk. Nusbaum C, Zody MC, Borowsky ML, Kamal M, Kodira CD, Taylor TD, Whittaker ...
... acen Centromere. var: Variable region; stalk: Stalk. National Institutes of Health. "Chromosome 3". Genetics Home Reference. ...
... acen Centromere. var: Variable region; stalk: Stalk. Gilbert F (2001). "Chromosome 8". Genet Test. 5 (4): 345-54. doi:10.1089/ ...
... acen Centromere. var: Variable region; stalk: Stalk. Gilbert F, Kauff N (2001). "Disease genes and chromosomes: disease maps of ...
... attaches to the centromeres. In most organisms the position of the centromere is not determined by the DNA sequence. Scientists ... Therefore neo-centromeres might contribute to the emergence of new species.. The insights into the central role of CenH3 for ... Centromeres are specialised regions of the genome, which can be identified under the microscope as the primary constriction in ... Centromeres provide a platform for the development of a protein complex known as the kinetochore. During cell division, the ...
Regions of synaptonemal complex assembled early in meiosis are often centromere-associated. We propose that centromere coupling ... A Synaptonemal Complex Protein Promotes Homology-Independent Centromere Coupling Message Subject. (Your Name) has forwarded a ... During meiosis in wild-type diploids, centromere couples are initially nonhomologous and then undergo switching until all ... describe a process in meiotic cells of budding yeast in which chromosomes become joined together in pairs at their centromeres ...
CENP-B protein , centromere protein B , Major centromere autoantigen B , CENP-B , centromere autoantigen B , major centromere ... Centromere Protein B (CENPB) ELISA Kits. CENPB product is a highly conserved protein that facilitates centromere formation. ... Additionally we are shipping Centromere Protein B Antibodies (41) and Centromere Protein B Proteins (7) and many more products ... More ELISA Kits for Centromere Protein B Interaction Partners. Mouse (Murine) Centromere Protein B (CENPB) interaction partners ...
Thirteen different centromere (CEN) mutations were tested for their effects on meiotic centromere function. YACs containing a ... Cis-acting determinants affecting centromere function, sister-chromatid cohesion and reciprocal recombination during meiosis in ... Cis-acting determinants affecting centromere function, sister-chromatid cohesion and reciprocal recombination during meiosis in ... Cis-acting determinants affecting centromere function, sister-chromatid cohesion and reciprocal recombination during meiosis in ...
Centromere structure appears to be organized in different, separable domains in order to accomplish these functions. Despite ... Also at the protein level few centromere proteins are conserved in all of these four organisms and many are unique to the ... Centromere domain organization and histone modifications. Bjerling, Pernilla Södertörn University, Avdelning Naturvetenskap. ... Centromere function requires the proper coordination of several subfunctions, such as kinetochore assembly, sister chromatid ...
Distribution of centromere histone H3 over the 180 bp clusters. The HTR12 protein is a centromere-specific histone H3 variant ... Functional rice centromeres are marked by a satellite repeat and a centromere-specific retrotransposon. Plant Cell 14, 1691- ... a centromere variant and a phosphorylated form) might be linked to different roles in centromere functionality; the former for ... since it interacts directly with centromere DNA and replaces histone H3 at the kinetochore region of active centromeres ( ...
A human centromere antigen (CENP-B) interacts with a short specific sequence in alphoid DNA, a human centromeric satellite. H ... A human centromere protein, CENP-B, has a DNA binding domain containing four potential alpha helices at the NH2 terminus, which ... These results imply that the interaction of the 80-kD centromere antigen with the CENP-B box in the alphoid repeats may play ... Centromere protein B assembles human centromeric alpha-satellite DNA at the 17-bp sequence, CENP-B box. ...
CENP B Protein , CENP-B Protein , Centromere Autoantigen 80K Definition A DNA-binding protein that interacts with a 17-base ... The protein is localized constitutively to the CENTROMERE and plays an important role in its maintenance.. ...
Foltz DR, Jansen LE, Bailey AO, Yates JR III., Bassett EA, Wood S, Black BE, Cleveland DW (2009) Centromere‐specific assembly ... Fujita Y, Hayashi T, Kiyomitsu T, Toyoda Y, Kokubu A, Obuse C, Yanagida M (2007) Priming of centromere for CENP‐A recruitment ... Silva MC, Bodor DL, Stellfox ME, Martins NM, Hochegger H, Foltz DR, Jansen LE (2012) Cdk activity couples epigenetic centromere ... Hayashi T, Ebe M, Nagao K, Kokubu A, Sajiki K, Yanagida M (2014) Schizosaccharomyces pombe centromere protein Mis19 links Mis16 ...
... the centromere of a higher eukaryote, particularly a plant, the telomere itself, the centromere ... Attempts to demonstrate that the S. pombe centromere-specific repetitive elements can function individually as centromeres have ... carrying the entire fission yeast centromere regions of chromosome 1 or 3 function as centromeres when introduced into acentric ... The centromere maps between tt-1 and ch-1 (denoted by the bracket), and is closely linked to the latter marker (indicated by ...
A new technique makes it much easier to study centromeres, and look for links to conditions such as Down syndrome. ... The centromere is the structure at the center of every X-shaped chromosome, where cells attached the long, thin spindles that ... The centromere is the structure at the center of every X-shaped chromosome, where cells attached the long, thin spindles that ... A new technique makes it much easier to study centromeres, and look for links to conditions such as Down syndrome. ...
The quest to understand the structure and function of the centromere dates back almost a century, when this specialized region ... Rattner, J. B. (1991). The structure of the mammalian centromere. Bioessays. 13, 51-56.PubMedCrossRefGoogle Scholar ... Pluta, A., Cooke, C. A. and Earnshaw, W. C. (1990). Structure of the human centromere at metaphase. TIBS. 15, 181-185.PubMed ... Centromere Protein Alpha Satellite Chromosome Movement Centromeric Chromatin Indian Muntjac These keywords were added by ...
Tag: centromere. Video: Mapping Uncharted Regions of Genomes by Siva Kasinathan. Posted on April 14, 2017. by Robin Banner ...
centromere (thing). See all of centromere, there is 1 more in this node. ... During anaphase of mitosis and of the second meiotic division, the two chromatids detach at the centromere, each moving to ...
i was negative for centromere b which causes scleroderma but another test i took tested all centromere antibodies and it didnt ... my question is does anyone have symptoms of sjorgens with centromere antibodies but centromere b negative? i was negative for ... The centromere antibody test is usually run to help diagnose or rule out CREST or scleroderma and to my knowledge it is not at ... this would have to be probably centromeres a or c.. the ana was also positive around 1 :160. so i have two autoimmune diseases ...
Plant Centromere Biology is dedicated to plant centromere research. Chapters cover the structure of centromeres from several ... Chapter 12 Centromere Evolution 159. Jiming Jiang. Chapter 13 Centromere-Mediated Generation of Haploid Plants 169. ... centromere drive and centromere misdivision. Additional chapters are dedicated to epigenetic modification and evolution of ... Chapter 5 Centromere Synteny among Brachypodium, Wheat, and Rice 57. Lili Qi, Bernd Friebe, and Bikram S. Gill ...
Centromere-proximal differentiation and speciation in Anopheles gambiae. Aram D. Stump, Meagan C. Fitzpatrick, Neil F. Lobo, ... Centromere-proximal differentiation and speciation in Anopheles gambiae. Aram D. Stump, Meagan C. Fitzpatrick, Neil F. Lobo, ... Centromere-proximal differentiation and speciation in Anopheles gambiae. Aram D. Stump, Meagan C. Fitzpatrick, Neil F. Lobo, ... Centromere-proximal differentiation and speciation in Anopheles gambiae Message Subject (Your Name) has sent you a message from ...
Centromeres were first thought to be genetic loci that direct the behavior of chromosomes. The physical role of the centromere ... "Regional centromeres" is the term coined to describe most centromeres, which typically form on regions of preferred DNA ... In regional centromeres, DNA sequences contribute to but do not define function. Regional centromeres contain large amounts of ... Point centromeres are smaller and more compact. DNA sequences are both necessary and sufficient to specify centromere identity ...
Centromere-encoded RNAs are integral components of the maize kinetochore. Christopher N. Topp, Cathy X. Zhong, and R. Kelly ... Centromere-encoded RNAs are integral components of the maize kinetochore Message Subject (Your Name) has sent you a message ... Here, we extend the evidence for RNA-chromatin interactions to the centromere core. The data indicate that maize centromeric ... These data provide evidence for a pool of protected, single-stranded centromeric RNA within the centromere/kinetochore complex. ...
Most plant, animal and fungal centromeres also bind a large protein, centromere protein C (CENP-C), that is characterized by a ... Adaptive evolution of centromere proteins in plants and animals.. Talbert PB1, Bryson TD, Henikoff S. ... The nucleosomes of centromeres are characterized by a special H3-like histone (CenH3), which evolves rapidly and adaptively in ... Centromeres represent the last frontiers of plant and animal genomics. Although they perform a conserved function in chromosome ...
Centromeres of mammalian chromosomes.. Willard HF1.. Author information. 1. Department of Genetics, Stanford University, CA ... The centromere is the major cis-acting genetic locus involved in chromosome segregation in mitosis and meiosis. The mammalian ... centromere is characterized by large amounts of tandemly repeated satellite DNA and by a number of specific centromere proteins ... the data are most consistent with a structural and possibly functional role for satellite DNA in the mammalian centromere. ...
The centromere is a special region of a chromosome, usually near the middle. It is where the two identical sister chromatids ... During mitosis the centromeres can be seen during the metaphase stage as a constriction at the chromosome. At this centromeric ... Retrieved from "https://simple.wikipedia.org/w/index.php?title=Centromere&oldid=6248447" ...
Centromere-associated protein E is a protein that in humans is encoded by the CENPE gene. Centromere-associated protein E is a ... Unlike other centromere-associated proteins, it is not present during interphase and first appears at the centromere region of ... "Entrez Gene: CENPE centromere protein E, 312kDa". Yen TJ, Li G, Schaar BT, et al. (1992). "CENP-E is a putative kinetochore ... 1991). "CENP-E, a novel human centromere-associated protein required for progression from metaphase to anaphase". EMBO J. 10 (5 ...
Centromere protein B also known as major centromere autoantigen B is an autoantigen protein of the cell nucleus. In humans, ... Centromere protein B is a highly conserved protein that facilitates centromere formation. It is a DNA-binding protein that is ... Centromere protein B is a potential biomarker of small-cell lung cancer. Centromere GRCh38: Ensembl release 89: ENSG00000125817 ... It is also considered a major centromere autoantigen recognized by sera from patients with anti-centromere antibodies. ...
Anti-centromere antibodies (ACAs; often styled solid, anticentromere) are autoantibodies specific to centromere and kinetochore ... Anti-centromere antibodies are found in approximately 60% of patients with limited systemic scleroderma and in 15% of those ... Anti-centromere antibodies present early in the course of disease and are notably predictive of limited cutaneous involvement ... The specificity of this test is >98%. Thus, a positive anti-centromere antibody finding is strongly suggestive of limited ...
  • On the other hand, when proteins bound to the biotinylated alphoid DNA carrying the 17-bp motif are recovered by streptavidin agarose and immunoblotted, the 80-kD centromere antigen (CENP-B) is detected. (rupress.org)
  • We also have assessed the meiotic segregation effects of rare gene conversion events occurring at sites located immediately adjacent to or distantly from the centromere region. (genetics.org)
  • During meiosis in wild-type diploids, centromere couples are initially nonhomologous and then undergo switching until all couples involve homologs. (sciencemag.org)
  • Regions of synaptonemal complex assembled early in meiosis are often centromere-associated. (sciencemag.org)
  • YACs containing a 31-bp deletion mutation in centromere DNA element II (CDEII delta 31) in either a heterocentric (mutant/wild type), homocentric (mutant/mutant) or monosomic (mutant/--) YAC pair configuration exhibited high levels (16-28%) of precocious sister-chromatid segregation (PSS) and increased levels (1-6%) of nondisjunction meiosis I (NDI). (genetics.org)
  • These results imply that the interaction of the 80-kD centromere antigen with the CENP-B box in the alphoid repeats may play some crucial role in the formation of specified structure and/or function of human centromere. (rupress.org)
more