*  Most recent papers in the journal Progress in Molecular Biology and Translational Science | Read by QxMD
Haploidy is a useful feature for the study of gene function because disruption of one allele in haploid cells, which contain ...
*  Doubled haploidy - Wikipedia
Doubled haploidy already plays an important role in hybrid cultivar production of vegetables, and the potential for ornamental ... Combined with doubled haploidy it becomes more effective. In marker assisted backcross conversion, a recipient parent is ... The number of species amenable to doubled haploidy has reached a staggering 250 in just a few decades. Response efficiency has ... The combination of doubled haploidy and molecular marker provides the short cut. In the back cross generation one itself a ...
*  WikiGenes - Haploidy
Disease relevance of Haploidy. *Deletion of the kinase domain of STE20 causes sterility in both haploid mating types [1]. ... Associations of Haploidy with chemical compounds. *Cytogenetic analysis of 26 PTC and 5 FTC showed clonal abnormalities in 9 ... Biological context of Haploidy. *beta 2-Microglobulin is encoded by a single gene per haploid genome in the mouse [12]. ... Anatomical context of Haploidy. *Disruption of T cell signaling networks and development by Grb2 haploid insufficiency [17]. ...
*  A Way to Stabilize Haploidy in Animal Cells
... News Aug 15, 2017 , Original story from CNIO ... Currently, the group is trying to discover chemical forms of stabilizing haploidy in animal cells and is exploring strategies ... Despite their potential, these cultures present some issues that make their use complicated because Haploidy is unstable and ... haploidy), mitosis is more prone to errors during the segregation of the chromosomes and this activates p53. This is the reason ...
*  PLNT3140 - Introductory Cytogenetics - Lecture 22, part 1 of 4
Haploidy- is a general term designating individuals or tissues (in mosaics) that have somatic cells with a gametic chromosome ... CHANGES IN CHROMOSOME NUMBER - HAPLOIDY. REFERENCES: SINGH, R.J. 1993. Plant Cytogenetics. Chapter 4. p.54-60. ... In all, there are 36 species of 26 genera and 10 families in which haploidy occurred spontaneously. ...
*  Plant Cytogenetics, Second Edition (ebook) by Ram J. Singh | 9781420038507
Haploidy. Male Sterility. MODE OF REPRODUCTION IN PLANTS. Introduction. Sexual Reproduction. Asexual Reproduction. The ...
*  EPO - T 1988/12 (Sclerotinia-resistant Brassica/PIONEER) of 10.11.2016
by doubled haploidy;. and. (d) selecting a descendent plant, wherein. (a) a solid component of the seed of the progeny plant ...
*  Free Genetics Flashcards about WVSOM -- Genetics
Haploidy. one complete set. diploidy. two complete sets. polyploidy. more than two sets. ...
*  Pollination bags - Wikipedia
Haploidy from Hordeum interspecific crosses. I. Polyhaploids of H. parodii and H. procerum. Theor. Appl. Genet. 49:209 217. ...
*  Geodakyan's evolutionary theory of sex - Wikipedia
"Transition from haploidy to dyploidy". Nature. 351 (6324): 315-317. Bibcode:1991Natur.351..315P. doi:10.1038/351315a0. Williams ...
*  HAP1 cells - Wikipedia
Due to their haploidy, HAP1 cells are very useful in biomedical research and genetic experiments. When working in diploid cells ... Near-haploidy in acute leukemia". Cancer. 40 (3): 1143-1148. doi:10.1002/1097-0142(197709)40:33.0.CO;2-4. ISSN 1097-0142. Baba ...
*  Category:Plant breeding - Wikimedia Commons
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. ...
*  Alexey Kondrashov - Wikipedia
Haploidy or diploidy: which is better? Nature 351:314-315 Kondrashov AS & Kondrashov FA. 1999. Interactions among quantitative ...
*  Frontiers | Drosophila As a Genetically Tractable Model for Social Insect Behavior | Ecology and Evolution
Crozier, R. H. (2008). Advanced eusociality, kin selection and male haploidy. Aust. J. Entomol. 47, 2-8. doi: 10.1111/j.1440- ...
*  Olaf Hagerup - Wikipedia
Hagerup, O. (1944) On fertilization, polyploidy and haploidy in Orchis maculatus L. sens. lat. Dansk Botanisk Arkiv 11 (5): 1- ... Hagerup, O. (1945) Facultative parthenogenesis and haploidy in Epipactis latifolia. Biologiske Meddelelser, Kongelige Danske ...
*  Oxygen and Sex | Proceedings of the Royal Society of London B: Biological Sciences
1991 Haploidy or diploidy: which is better? Nature 351, 314-315. (doi:10.1038/351314a0). ... 2003 An evolutionary advantage of haploidy in large yeast populations. Science 299, 555-558. (doi:10.1126/science.1078417). ... Meiosis II is just a mitosis and regenerates haploidy, and this way the first meiosis-mixis cycles could have been established ...
*  Genetics Flashcards by Xisain 314 | Brainscape
When a cell contains an abnormal number of chromosomes which is not an exact multiple of haploidy number. ... When a cell contains an exact multiple of haploidy number which is >2. ...
*  Ploidy - Wikipedia
The term ploidy is a back-formation from haploidy and diploidy. Ploid is a combination of Ancient Greek -παλτος (-paltos), - ... Some studies suggest that selection is more likely to favor diploidy in host species and haploidy in parasite species. The ...
*  Conversion Technology for the Separation of Maternal and Paternal Copies of Any Autosomal Chromosome in Somatic Cell Hybrids -...
Conversion Technology (CT) is a streamlined version of somatic cell hybrid preparation that was developed to be amenable for use as a mutation detection method and as a diagnostic tool for individual patients
*  ASMscience | DNA Polymorphisms in Gat
A) p53 and p27 are examples of genes not required for development; however, haploidy lends to tumor predisposition. (B) RB1 is ... A) p53 and p27 are examples of genes not required for development; however, haploidy lends to tumor predisposition. (B) RB1 is ... required for both embryonic development and tumor suppression, but haploidy accommodates the former and nearly the latter. (C) ... required for both embryonic development and tumor suppression, but haploidy accommodates the former and nearly the latter. (C) ...
*  Update: Ark of the Covenant - October 5, 1998 | Anchor Stone International
... "haploidy". There have been known examples of females born with only half the normal chromosome count - 23 - but never a male ...
*  Ploidy dynamics and evolvability | Philosophical Transactions of the Royal Society B: Biological Sciences
2004 Haploidy, diploidy and evolution of antifungal drug resistance in Saccharomyces cerevisiae. Genetics 168, 1915-1923. (doi: ...
*  ZFIN Publication: Alexander et al., 1998
Haploidy; Heart/embryology*; Male; Morphogenesis; Mosaicism*; Mutation; Zebrafish/embryology; Zebrafish/genetics* ...
*  ZFIN Publication: Johnson et al., 1994
The zebrafish has recently emerged as a useful system for understanding vertebrate developmental genetics, despite the lack of a linkage map. To identify DNA-based genetic polymorphisms for constructing a genetic map, we have screened a collection of RAPD primers for their utility in identifying genetic polymorphisms between two laboratory strains of zebrafish. Here, we report 116 primers that identify 721 strain-specific genetic markers and show how they can be used in haploid genetics of zebrafish ...

(1/1093) Standardized nomenclature for inbred strains of mice: sixth listing.

Rules for designating inbred strains of mice are presented, along with a list of strains with their origins and characteristics, a table of biochemical polymorphisms, and standard subline designations.  (+info)

(2/1093) Mapping of the homothallic genes, HM alpha and HMa, in Saccharomyces yeasts.

Two of the three homothallic genes, HM alpha and HMa, showed direct linkage to the mating-type locus at approximately 73 and 98 strans (57 and 65 centimorgans [cM], respectively, whereas, the other, HO, showed no linkage to 25 standard markers distributed over 17 chromosomes including the mating-type locus. To determine whether the HM alpha and HMa loci located on the left or right side of the mating-type locus, equations for three factor analysis of three linked genes were derived. Tetrad data were collected and were compared with expected values by chi 2 statistics. Calculations indicated that the HM alpha gene is probably located on the right arm at 95 strans (65 cM) from the centromere and the HMa locus at approximately 90 strans (64 cM) on the left arm of chromosome III.  (+info)

(3/1093) SWM1, a developmentally regulated gene, is required for spore wall assembly in Saccharomyces cerevisiae.

Meiosis in Saccharomyces cerevisiae is followed by encapsulation of haploid nuclei within multilayered spore walls. Formation of this spore-specific wall requires the coordinated activity of enzymes involved in the biosynthesis of its components. Completion of late events in the sporulation program, leading to spore wall formation, requires the SWM1 gene. SWM1 is expressed at low levels during vegetative growth but its transcription is strongly induced under sporulating conditions, with kinetics similar to those of middle sporulation-specific genes. Homozygous swm1Delta diploids proceed normally through both meiotic divisions but fail to produce mature asci. Consistent with this finding, swm1Delta mutant asci display enhanced sensitivity to enzymatic digestion and heat shock. Deletion of SWM1 specifically affects the expression of mid-late and late sporulation-specific genes. All of the phenotypes observed are similar to those found for the deletion of SPS1 or SMK1, two putative components of a sporulation-specific MAP kinase cascade. However, epistasis analyses indicate that Swm1p does not form part of the Sps1p-Smk1p-MAP kinase pathway. We propose that Swm1p, a nuclear protein, would participate in a different signal transduction pathway that is also required for the coordination of the biochemical and morphological events occurring during the last phase of the sporulation program.  (+info)

(4/1093) Genealogies and weak purifying selection.

The assumption that selection alters the genealogical tree of a sample of alleles from a population relative to the neutral expectation underlies several "tests of neutrality." Two recent papers have studied the effect of purifying selection; their suggestive but incomplete results indicate that, in the single site case, the shape of a gene genealogy for a locus may differ only from the neutral expectation. We verify this finding for weak selection using the "ancestral selection graph." We consider a wider range of models, including both a four-allele single-site model and an infinite-sites model. Our results confirm the previous claim for the symmetric-mutation single site model. We emphasize, however, that a neutral-seeming genealogy is consistent with detectable effects of selection on the distribution of allele frequences within the sample. With selection operating, the information about a sample cannot be reduced to the genealogy. As a result, a distinction needs to be made between the selected sites themselves, for which the genealogy offers insufficient information, and linked neutral variation. This distinction seems to have been overlooked in previous papers, yet it has significant implications for the interpretation of data on DNA sequence variation. In particular, it predicts that under purifying selection, the frequency spectrum of neutral mutations will not reflect the skew toward rare polymorphisms at replacement sites even if there is no recombination between them. We caution, however, that the effect of weak selection on the genealogy is specific to the model; a (more realistic) model of multiple linked sites could lead to a more distorted genealogy than is observed for a single site.  (+info)

(5/1093) The relationship between DNA methylation and chromosome imprinting in the coccid Planococcus citri.

The phenomenon of chromosome, or genomic, imprinting indicates the relevance of parental origin in determining functional differences between alleles, homologous chromosomes, or haploid sets. In mealybug males (Homoptera, Coccoidea), the haploid set of paternal origin undergoes heterochromatization at midcleavage and remains so in most of the tissues. This different behavior of the two haploid sets, which depends on their parental origin, represents one of the most striking examples of chromosome imprinting. In mammals, DNA methylation has been postulated as a possible molecular mechanism to differentially imprint DNA sequences during spermatogenesis or oogenesis. In the present article we addressed the role of DNA methylation in the imprinting of whole haploid sets as it occurs in Coccids. We investigated the DNA methylation patterns at both the molecular and chromosomal level in the mealybug Planococcus citri. We found that in both males and females the paternally derived haploid set is hypomethylated with respect to the maternally derived one. Therefore, in males, it is the paternally derived hypomethylated haploid set that is heterochromatized. Our data suggest that the two haploid sets are imprinted by parent-of-origin-specific DNA methylation with no correlation with the known gene-silencing properties of this base modification.  (+info)

(6/1093) The Yck2 yeast casein kinase 1 isoform shows cell cycle-specific localization to sites of polarized growth and is required for proper septin organization.

Casein kinase 1 protein kinases are ubiquitous and abundant Ser/Thr-specific protein kinases with activity on acidic substrates. In yeast, the products of the redundant YCK1 and YCK2 genes are together essential for cell viability. Mutants deficient for these proteins display defects in cellular morphogenesis, cytokinesis, and endocytosis. Yck1p and Yck2p are peripheral plasma membrane proteins, and we report here that the localization of Yck2p within the membrane is dynamic through the cell cycle. Using a functional green fluorescent protein (GFP) fusion, we have observed that Yck2p is concentrated at sites of polarized growth during bud morphogenesis. At cytokinesis, GFP-Yck2p becomes associated with a ring at the bud neck and then appears as a patch of fluorescence, apparently coincident with the dividing membranes. The bud neck association of Yck2p at cytokinesis does not require an intact septin ring, and septin assembly is altered in a Yck-deficient mutant. The sites of GFP-Yck2p concentration and the defects observed for Yck-deficient cells together suggest that Yck plays distinct roles in morphogenesis and cytokinesis that are effected by differential localization.  (+info)

(7/1093) Genetic factors affecting the impact of DNA polymerase delta proofreading activity on mutation avoidance in yeast.

Base selectivity, proofreading, and postreplication mismatch repair are important for replication fidelity. Because proofreading plays an important role in error correction, we have investigated factors that influence its impact in the yeast Saccharomyces cerevisiae. We have utilized a sensitive mutation detection system based on homonucleotide runs of 4 to 14 bases to examine the impact of DNA polymerase delta proofreading on mutation avoidance. The contribution of DNA polymerase delta proofreading on error avoidance was found to be similar to that of DNA polymerase epsilon proofreading in short homonucleotide runs (A4 and A5) but much greater than the contribution of DNA polymerase epsilon proofreading in longer runs. We have identified an intraprotein interaction affecting mutation prevention that results from mutations in the replication and the proofreading regions, resulting in an antimutator phenotype relative to a proofreading defect. Finally, a diploid strain with a defect in DNA polymerase delta proofreading exhibits a higher mutation rate than a haploid strain. We suggest that in the diploid population of proofreading defective cells there exists a transiently hypermutable fraction that would be inviable if cells were haploids.  (+info)

(8/1093) Maximal stimulation of meiotic recombination by a yeast transcription factor requires the transcription activation domain and a DNA-binding domain.

The DNA sequences located upstream of the yeast HIS4 represent a very strong meiotic recombination hotspot. Although the activity of this hotspot requires the transcription activator Rap1p, the level of HIS4 transcription is not directly related to the level of recombination. We find that the recombination-stimulating activity of Rap1p requires the transcription activation domain of the protein. We show that a hybrid protein with the Gal4p DNA-binding domain and the Rap1p activation domain can stimulate recombination in a strain in which Gal4p-binding sites are inserted upstream of HIS4. In addition, we find recombination hotspot activity associated with the Gal4p DNA-binding sites that is independent of known transcription factors. We suggest that yeast cells have two types of recombination hotspots, alpha (transcription factor dependent) and beta (transcription factor independent).  (+info)

  • methods
  • Studies were conducted comparing DH method and other conventional breeding methods and it was concluded that adoption of doubled haploidy does not lead to any bias of genotypes in populations, and random DHs were even found to be compatible to selected line produced by conventional pedigree method. (wikipedia.org)
  • term
  • Haploidy - is a general term designating individuals or tissues (in mosaics) that have somatic cells with a gametic chromosome number (n). (umanitoba.ca)
  • nature
  • This is possible with doubled haploidy organisms because of their true breeding nature and because they can conveniently be produced in large numbers. (wikipedia.org)