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  • 22q11.2
  • Tony Simon runs a clinic dedicated to supporting children with chromosome 22q11.2 deletion syndrome and educating health-care providers about the disorder. (ucdavis.edu)
  • An article published in the June issue of the journal Nature Reviews: Neuroscience provides one of the first comprehensive overviews of the genetic, neural and cognitive bases of a frequently undiagnosed congenital disorder with an array of complex genetic, medical, neurological, behavioral and psychiatric features: the often baffling chromosome 22q11.2 deletion syndrome (22q11.2DS). (ucdavis.edu)
  • What began as six families - joined together by the challenges of autism, and motivated by an urgent desire to find answers - is now an internationally renowned research center for understanding autism, fragile X syndrome, Tourette syndrome, chromosome 22q11.2 deletion syndrome and ADHD. (ucdavis.edu)
  • People with a 22q11.2 deletion have a very small piece of chromosome 22 missing (thus it is called a deletion). (upenn.edu)
  • In 1991, Deborah Driscoll, M.D., a member of Dr. Emanuel's laboratory group, detected a submicroscopic deletion of chromosome 22q11.2 in the majority of patients with DiGeorge syndrome using special 'molecular' tests. (upenn.edu)
  • chromosomal
  • In 1981, Dr. de la Chapelle in France, and in 1982, Richard Kelley, M.D., along with Elaine Zackai, M.D. and Beverly Emanuel, Ph.D. at the Children's Hospital of Philadelphia in the U.S.A., found that patients with DiGeorge syndrome had a rearrangement of chromosome 22 which caused them to be missing a very small piece of chromosomal material on the long arm (q11.2) of chromosome 22. (upenn.edu)
  • investigate
  • This is an ideal situation for research on sex chromosomes, because the processes we wish to study have had some time to leave detectable genomic footprints, but have not yet removed the material we want to investigate. (lu.se)
  • In this study, we investigate patterns of genetic diversity in noncoding regions across the entire X chromosome of a global sample of 26 unrelated genetic females. (genetics.org)
  • syndrome
  • Over the years, Dr. Emanuel's group at the Children's Hospital of Philadelphia worked very hard to establish the fact that 25% of patients with DiGeorge syndrome had a visible deletion of material on chromosome 22 when they looked under the microscope. (upenn.edu)
  • discovery
  • Ever since their discovery, these chromosomes have captivated researchers because of their obvious involvement in fundamental aspects of an organism's life, such as sex determination, sexual reproduction and sexual conflicts. (lu.se)
  • long
  • The q11.2 tells everyone who works in genetics that the area missing is in a very specific spot on the 'q' arm, which is also called the long arm of the chromosome. (upenn.edu)
  • among
  • AMONG species with genetic sex determination, sex is determined in the vast majority by a single locus or chromosome ( B ull 1983 ). (genetics.org)
  • lack
  • This lack of detailed knowledge about sex chromosome evolution compromises our understanding of fundamental biological questions (e.g. the evolution of sexual conflicts) as well as more practical ones (e.g. about sex-linked genetic diseases). (lu.se)
  • genes
  • Activating genes for reprogramming factors for a short time transforms large numbers of differentiated cells into multipotent forms that could be useful for cell-based therapies. (the-scientist.com)
  • In their analysis, for example, the scientists found that about one in eight genes associated with cell proliferation and other relevant cell functions switch from relatively loose A compartments to more restrictive B compartments. (phys.org)
  • Hi-C" chromosome conformation capture, first published in 2009, allowed them to discover the changes in genes' positioning in A or B chromatin compartments. (phys.org)
  • Now the team is delving deeper into the compartment switches (between A and B) that change the regulation of genes in senescent vs. nonsenescent cells, Neretti said. (phys.org)
  • It's not like most tumor suppressor genes, which when mutated lead to either enhanced cell proliferation or decreased cell death," he said. (medpagetoday.com)
  • Indeed, when the researchers compared gene expression in two cell lines that differed only in that the STAG2 gene was turned on or off, just 16 of 28,869 genes (or 0.06%) changed their expression levels. (medpagetoday.com)
  • This results in sequential transfer of genes on the bacterial chromosome. (wikipedia.org)
  • Bacterial geneticists make use of this principle to map the genes on the bacterial chromosome. (wikipedia.org)
  • By using Hfr and F− strains with one strain carrying mutations in several genes, each affecting a metabolic function or causing antibiotic resistance, and examining the phenotype of the recipient cells on selective agar plates, one can deduce which genes are transferred into the recipient cells first and therefore are closer to the oriT sequence on the chromosome. (wikipedia.org)
  • The vector incorporates genes into chromosomes. (wikipedia.org)
  • The expressed nucleases then knock out and replace genes in the chromosome. (wikipedia.org)
  • At the same time, some phage genes are left behind in the bacterial chromosome. (wikipedia.org)
  • Specialized transduction occurs when the prophage excises imprecisely from the chromosome so that bacterial genes lying adjacent to the prophage are included in the excised DNA. (wikipedia.org)
  • The excised DNA is then packaged into a new virus particle, which then delivers the DNA to a new bacterium, where the donor genes can be inserted into the recipient chromosome or remain in the cytoplasm, depending on the nature of the bacteriophage. (wikipedia.org)
  • Transduction with viral vectors can be used to insert or modify genes in mammalian cells. (wikipedia.org)
  • telomeres
  • A Johns Hopkins team has stopped in its tracks a form of blood cancer in mice by engineering and inactivating an enzyme, telomerase, thereby shortening the ends of chromosomes, called telomeres. (hopkinsmedicine.org)
  • Normally, when telomeres get critically short, the cell commits suicide as a means of protecting the body," says Carol Greider, Ph.D., the Daniel Nathans chair of molecular biology and genetics at Johns Hopkins. (hopkinsmedicine.org)
  • Telomerase helps maintain the caps or ends of chromosomes called telomeres, which shrink each time a cell divides and eventually - when the chromosomes get too short - force the cell to essentially commit suicide. (hopkinsmedicine.org)
  • In their research, the scientists saw that while the chromosomes' arms and the "telomeres" at their tips scrunched up, the relatively tiny middle-the centromere-expanded. (phys.org)
  • Telomeres protect the end of the chromosome from DNA damage or from fusion with neighbouring chromosomes. (wikipedia.org)
  • The role of telomeres and telomerase in cell aging and cancer was established by scientists at biotechnology company Geron with the cloning of the RNA and catalytic components of human telomerase and the development of a polymerase chain reaction (PCR) based assay for telomerase activity called the TRAP assay, which surveys telomerase activity in multiple types of cancer. (wikipedia.org)
  • Telomerase replaces short bits of DNA known as telomeres, which are otherwise shortened when a cell divides via mitosis. (wikipedia.org)
  • In baboon skeletal muscle, which consists of fully differentiated post-mitotic cells, less than 3% of myonuclei contain damaged telomeres and this percentage does not increase with age. (wikipedia.org)
  • gene
  • Combining gene editing and stem-cell induction improves efficiency of functional genetic analyses. (the-scientist.com)
  • A new study helps by showing that chromosomes become somewhat transformed, altering their patterns of gene expression. (phys.org)
  • Instead it's a tumor suppressor gene with a different function -- maintaining normal chromosome number and structure. (medpagetoday.com)
  • Using a technique called human somatic cell gene targeting, they corrected the defective STAG2 gene in two aneuploid glioblastoma cell lines. (medpagetoday.com)
  • Interestingly, the gene is just the second cancer-causing gene found on a sex chromosome, Waldman and colleagues reported. (medpagetoday.com)
  • The gene is on the X chromosome and -- since men have only one X and women, with two, have only one that is active -- a single mutation is enough to turn the gene off, which might help explain the "unusually high prevalence of STAG2 mutations in cancer," Waldman said. (medpagetoday.com)
  • Following λ-red operon activity induction, a linear, double-stranded cassette encoding a selectable marker, such as antibiotic resistance, is transformed into the cells in place of the target gene and incorporated into the DNA behind a specific inducible promoter. (wikipedia.org)
  • A plasmid expressing flippase (FLP) can be transformed into the recombined cells, which can specifically cleave FLP recognition target sites (FRTs) flanking the antibiotic resistance gene. (wikipedia.org)
  • Gene therapy is the therapeutic delivery of nucleic acid into a patient's cells as a drug to treat disease. (wikipedia.org)
  • The adeno-associated virus serotype 1 (AAV1) viral vector delivers an intact copy of the human lipoprotein lipase (LPL) gene to muscle cells. (wikipedia.org)
  • comment: Note that this term is intended to annotate gene products that are attached to the plasma membrane or cell wall. (wikipedia.org)
  • exact_synonym: "extracellular" Note that this term is intended to annotate gene products that are not attached to the cell surface. (wikipedia.org)
  • organisms
  • The cell (from Latin cella, meaning "small room") is the basic structural, functional, and biological unit of all known living organisms. (wikipedia.org)
  • Cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells, that cells are the fundamental unit of structure and function in all living organisms, that all cells come from preexisting cells, and that all cells contain the hereditary information necessary for regulating cell functions and for transmitting information to the next generation of cells. (wikipedia.org)
  • Beyond unicellular organisms) Telomerase is active in normal stem cells and most cancer cells, but is normally absent from, or at very low levels in, most somatic cells. (wikipedia.org)
  • By using TERC, TERT can add a six-nucleotide repeating sequence, 5'-TTAGGG (in vertebrates, the sequence differs in other organisms) to the 3' strand of chromosomes. (wikipedia.org)
  • He propounded the concept of speciation in asexual organisms and the some of techniques he developed for the study of chromosomes with respect to their physical and chemical nature, such as repetitive DNA orcein banding, multiple DNA analysis and analysis of chemical nature of chromosomes, are being practiced globally. (wikipedia.org)
  • Those processes specifically pertinent to the functioning of integrated living units: cells, tissues, organs, and organisms. (wikipedia.org)
  • This process allows for the high-fidelity passage of hereditary/genetic information from parental cell to daughter cell and is thus essential to all organisms. (wikipedia.org)
  • Cellular components are the complex biomolecules and structures of which cells, and thus living organisms, are composed. (wikipedia.org)
  • The smallest organisms are single cells, while the largest organisms are assemblages of trillions of cells. (wikipedia.org)
  • 2017
  • Arun Kumar Sharma (1924-2017), popularly known as AKS, was an Indian cytogeneticist, cell biologist, cytochemist and a former Sir Rashbehary Ghose Professor and Head of the Department of Botany at the University of Kolkata. (wikipedia.org)
  • spindle
  • As the time for cell division draws near, the chromosomes (red) align in the mitotic spindle and become attached to the microtubules (green). (washington.edu)
  • When chromosome pairs are properly connected to the spindle, with one attached to microtubules on the right and the other to microtubules on the left, the kinetochore comes under mechanical tension and the attachment becomes stabilized, sort of like steadying a load by tightening ropes on either side. (washington.edu)
  • In the new study, they investigated the effects of this imbalance on the cell division cycle by interfering with the process of proper chromosome attachment to the spindle, the structure that holds chromosomes in place at the cell's equator before division. (technologynetworks.com)
  • In the first meiotic division, the homologs are segregated to separate daughter cells by the spindle apparatus. (wikipedia.org)
  • Biology
  • If we can re-activate this immune recognition system, that would be a really good way of getting rid of cancer cells," says Angelika Amon, the Kathleen and Curtis Marble Professor in Cancer Research in MIT's Department of Biology, a member of the Koch Institute for Integrative Cancer Research, and the senior author of the study. (technologynetworks.com)
  • The study of cells is called cell biology. (wikipedia.org)
  • molecular
  • Originally trained in mechanical engineering, Asbury studies molecular motors in cells. (washington.edu)
  • By reading selected primary literature covering several decades, we will build an understanding of the cell cycle by focusing on chromosomes and the associated molecular machinery. (upenn.edu)
  • Molecular Cell 33, 335-343, February 13, 2009 (doi:10.1016/j.molcel.2009.01.016). (innovations-report.com)
  • They showed that a molecular corollary of aging is that senescent cells lose their tight chromatin grip on often-harmful sequences of DNA called transposons, leading to greater replication of those "rogue" elements. (phys.org)
  • cellular
  • Cellular senescence-when a cell can no longer divide-is a programmed stage in a cell's life cycle. (phys.org)
  • Table 1: Cellular effects of viral infections Cytocidal infections are often associated with changes in cell morphology, physiology and are thus important for the complete viral replication and transformation. (wikipedia.org)
  • While the majority of cellular components are located within the cell itself, some may exist in extracellular areas of an organism. (wikipedia.org)
  • behaviour
  • Aided by the rediscovery at the start of the 1900s of Gregor Mendel's earlier work, Boveri was able to point out the connection between the rules of inheritance and the behaviour of the chromosomes. (wikipedia.org)
  • He redefined angiosperm taxonomy, proposed new concepts of the dynamic DNA and dynamic structure and behaviour of chromosomes and suggested the use of embryo irradiation and in-vitro cultures for the generation of variability, and tissue culture as a tool for conservation of endangered species and for maintaining genetic variability. (wikipedia.org)
  • cytoplasm
  • During infection, the phage particle recognizes and binds to its host, E. coli, causing DNA in the head of the phage to be ejected through the tail into the cytoplasm of the bacterial cell. (wikipedia.org)
  • organism
  • That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid. (wikipedia.org)
  • Citation
  • citation needed] Wilhelm Roux suggested that each chromosome carries a different genetic load. (wikipedia.org)
  • In adults, telomerase is highly expressed only in cells that need to divide regularly especially in male sperm cells[citation needed] but also in epidermal cells, in activated T cell and B cell lymphocytes, as well as in certain adult stem cells, but in the great majority of cases somatic cells do not express telomerase. (wikipedia.org)
  • advances
  • Andrzej Tarkowski's research laid the groundwork for future advances in cloning, stem cell research, and in vitro fertilization. (the-scientist.com)
  • instability
  • That instability -- including whole chromosome instability, mutagenesis, and increased sensitivity to genotoxic stress - appeared to provide a growth advantage, they reported. (medpagetoday.com)
  • copies
  • and the X and Y sex chromosomes, extra copies of which may cause various disorders but are not usually lethal. (technologynetworks.com)
  • Because the number of chromosomes is halved during meiosis, gametes can fuse (i.e. fertilization) to form a diploid zygote that contains two copies of each chromosome, one from each parent. (wikipedia.org)
  • Although the process of meiosis is related to the more general cell division process of mitosis, it differs in two important respects: Meiosis begins with a diploid cell, which contains two copies of each chromosome, termed homologs. (wikipedia.org)
  • replication
  • In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells, each with half the number of chromosomes as the original parent cell. (wikipedia.org)
  • Immediately following DNA replication, meiotic cells enter a prolonged G2-like stage known as meiotic prophase. (wikipedia.org)
  • First, the cell undergoes DNA replication, so each homolog now consists of two identical sister chromatids. (wikipedia.org)
  • The cells then proceed to a second division without an intervening round of DNA replication. (wikipedia.org)
  • In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent. (wikipedia.org)
  • Eukaryotic DNA replication is a conserved mechanism that restricts DNA replication to once per cell cycle. (wikipedia.org)
  • Replication processes permit the copying of a single DNA double helix into two DNA helices, which are divided into the daughter cells at mitosis. (wikipedia.org)
  • In G1 phase of the cell cycle, many of the DNA replication regulatory processes are initiated. (wikipedia.org)
  • Association of the origin recognition complex (ORC) with a replication origin is required to recruit both cell division cycle 6 protein (Cdc6) and chromatin licensing and DNA replication factor 1 protein (Cdt1), which initiate the assembly of the pre-RC. (wikipedia.org)
  • machinery
  • New research published Nov. 25 in Nature shows that cells stabilize this machinery using simple mechanical tension. (washington.edu)
  • When viruses, including bacteriophages (viruses that infect bacteria), infect bacterial cells, their normal mode of reproduction is to harness the replicational, transcriptional, and translation machinery of the host bacterial cell to make numerous virions, or complete viral particles, including the viral DNA or RNA and the protein coat. (wikipedia.org)
  • phage
  • The phage can then penetrate the cell membrane and inject the viral DNA into the host cell. (wikipedia.org)
  • Usually, a "lytic cycle" ensues, where the lambda DNA is replicated and new phage particles are produced within the cell. (wikipedia.org)
  • Lambda phage is a non-contractile tailed phage, meaning during an infection event it cannot 'force' its DNA through a bacterial cell membrane. (wikipedia.org)
  • membrane
  • A prokaryotic cell has three architectural regions: Enclosing the cell is the cell envelope - generally consisting of a plasma membrane covered by a cell wall which, for some bacteria, may be further covered by a third layer called a capsule. (wikipedia.org)
  • Though most prokaryotes have both a cell membrane and a cell wall, there are exceptions such as Mycoplasma (bacteria) and Thermoplasma (archaea) which only possess the cell membrane layer. (wikipedia.org)
  • The external part of the cell wall and/or cell membrane. (wikipedia.org)
  • A structure that lies outside the plasma membrane and surrounds the entire cell. (wikipedia.org)
  • defects
  • This knowledge would potentially lead to ways to correct defects before they occur, or allow us to try to target cells with the wrong number of chromosomes to prevent them from dividing again. (washington.edu)
  • After the correction, daughter cells no longer had defects in the cell division process. (medpagetoday.com)
  • recipient
  • When the new DNA is inserted into this recipient cell it can fall to one of three fates The DNA will be absorbed by the cell and be recycled for spare parts. (wikipedia.org)
  • division
  • This stabilization helps assure an accurate division and distribution of the chromosomes. (washington.edu)
  • These appear on the chromosomes and attach to dynamic filaments during cell division. (washington.edu)
  • Play media Meiosis /maɪˈoʊsɪs/ ( listen) is a specialized type of cell division that reduces the chromosome number by half, creating four haploid cells, each genetically distinct from the parent cell that gave rise to them. (wikipedia.org)
  • However, others use the concept in a narrower sense, to refer to the individualized portions of chromatin during cell division, visible under light microscopy due to high condensation. (wikipedia.org)
  • At the limit the cells become senescent and cell division stops. (wikipedia.org)
  • He introduced a new protocol for inducing division in adult nuclei through chemical application which assisted in cell rejuvenation. (wikipedia.org)
  • Archaea
  • Archaea and bacteria are generally similar in size and shape, although a few archaea have very strange shapes, such as the flat and square-shaped cells of Haloquadratum walsbyi. (wikipedia.org)
  • Meiosis
  • Name the following: 1.The phase of meiosis at which homologus chromosomes are separated. (topperlearning.com)
  • Before meiosis begins, during S phase of the cell cycle, the DNA of each chromosome is replicated so that it consists of two identical sister chromatids, which remain held together through sister chromatid cohesion. (wikipedia.org)
  • Thus, alternating cycles of meiosis and fertilization enable sexual reproduction, with successive generations maintaining the same number of chromosomes. (wikipedia.org)
  • Meiosis produces haploid gametes (ova or sperm) that contain one set of 23 chromosomes. (wikipedia.org)
  • In some plants, fungi, and protists meiosis results in the formation of spores: haploid cells that can divide vegetatively without undergoing fertilization. (wikipedia.org)
  • sequence
  • Therefore, counterselection against the cells containing the marker needs to be performed in order to identify the cells that have successfully incorporated the linear DNA into the target sequence. (wikipedia.org)
  • Telomerase can bind the first few nucleotides of the template to the last telomere sequence on the chromosome, add a new telomere repeat (5'-GGTTAG-3') sequence, let go, realign the new 3'-end of telomere to the template, and repeat the process. (wikipedia.org)
  • recombination events
  • Jentsch and colleagues speculate that this tethering to the nuclear envelope could be a safety measure of cells to prevent erroneous and unwanted recombination events, which can have catastrophic consequences like cancer development or cell death. (innovations-report.com)
  • lysis
  • This is followed by cell lysis, releasing the cell contents, including virions that have been assembled, into the environment. (wikipedia.org)
  • protein
  • Cytocidal infections can cause fusion of adjacent cells, disruption of transport pathways including ions and other cell signals, disruption of DNA, RNA and protein synthesis, and nearly always leads to cell death. (wikipedia.org)
  • DNA must be administered, reach the damaged cells, enter the cell and either express or disrupt a protein. (wikipedia.org)
  • Bacteriophage Lambda binds to an E. coli cell by means of its J protein in the tail tip. (wikipedia.org)
  • initially
  • This paper very convincingly and clearly shows that when chromosomes are lost or gained, initially cells can't tell if their chromosomes have mis-segregated," says David Pellman, a professor of pediatric oncology at Dana-Farber Cancer Institute who was not involved in the study. (technologynetworks.com)
  • dormant
  • Persistent infections involve viral material that lays dormant within a cell until activated by some stimulus. (wikipedia.org)
  • persistent
  • This infection causes a host cell to become malignant and can be either cytocidal (usually in the case of RNA viruses) or persistent (usually in the case of DNA viruses). (wikipedia.org)
  • There are three types of persistent infections, latent, chronic and slow, in which the virus stays inside the host cell for prolonged periods of time. (wikipedia.org)
  • attachment
  • When the microtubules (red) don't line up properly on either side of a pair of chromosomes (blue), the tension is weak, allowing the microtubule attachment to be released and fixed. (washington.edu)
  • monocytes
  • 9kD granulysin is also a chemoattractant for T lymphocytes, monocytes, and other inflammatory cells and activates the expression of a number of cytokines, including RANTES, MCP-1, MCP-3, MIP-1α, IL-10, IL-1, IL-6 and IFNα. (wikipedia.org)
  • Scaffold
  • They bind to DnaA-ADP and DnaA-ATP with equal affinities and are bound by DnaA throughout most of the cell cycle and forms a scaffold on which rest of the orisome assembles. (wikipedia.org)
  • nuclear
  • When the cell is treated with TGF-β, HIPK2, a nuclear kinase, phosphorylates Daxx and the activated Daxx in turn activates the JNK pathway (see "The Daxx Pathway" figure). (wikipedia.org)
  • Although
  • Although pancreatic beta cells produce adequate insulin in infancy, the capacity for insulin production declines thereafter. (wikipedia.org)
  • growth
  • Media conditions that support fast growth in bacteria also couples with shorter inter-initiation time in them, i.e. the doubling time in fast growing cells is less as compared to the slow growth. (wikipedia.org)
  • In other words, it is possible that in fast growth conditions the grandmother cells starts replicating its DNA for grand daughter cell. (wikipedia.org)
  • methods
  • Sequenom is the exclusive licensee of U.S. Patent No. 6,258,540, which claims methods of using cell-free fetal DNA (cffDNA) circulating in maternal plasma (cell-free blood) to diagnose fetal abnormalities. (wikipedia.org)
  • Conditions
  • Then, they could reliably identify fetal DNA, which would in turn allow them to diagnose certain fetal genetic conditions such as Down Syndrome , which can be detected by observing presence of extra chromosomes. (wikipedia.org)
  • surface
  • Seeds are obovate, narrowly winged at the apex and acute at the base, pale brown, pubescent with hair-like outgrowths of the tegument cell radial walls, which give the surface a silky appearance. (wikipedia.org)
  • data
  • The data used in this workflow is an RNA-Seq experiment of airway smooth muscle cells treated with dexamethasone, a synthetic glucocorticoid steroid with anti-inflammatory effects. (bioconductor.org)
  • another
  • Prokaryotic DNA replication is the process by which a prokaryote duplicates its DNA into another copy that is passed on to daughter cells. (wikipedia.org)