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Relevant bibliographies by topics / W chromosome

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Academic literature on the topic 'W chromosome'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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Journal articles on the topic "W chromosome"

1

Singchat, Worapong, Syed Farhan Ahmad, Nararat Laopichienpong, Aorarat Suntronpong, Thitipong Panthum, Darren K. Griffin, and Kornsorn Srikulnath. "Snake W Sex Chromosome: The Shadow of Ancestral Amniote Super-Sex Chromosome." Cells 9, no. 11 (October 31, 2020): 2386. http://dx.doi.org/10.3390/cells9112386.

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Heteromorphic sex chromosomes, particularly the ZZ/ZW sex chromosome system of birds and some reptiles, undergo evolutionary dynamics distinct from those of autosomes. The W sex chromosome is a unique karyological member of this heteromorphic pair, which has been extensively studied in snakes to explore the origin, evolution, and genetic diversity of amniote sex chromosomes. The snake W sex chromosome offers a fascinating model system to elucidate ancestral trajectories that have resulted in genetic divergence of amniote sex chromosomes. Although the principal mechanism driving evolution of the amniote sex chromosome remains obscure, an emerging hypothesis, supported by studies of W sex chromosomes of squamate reptiles and snakes, suggests that sex chromosomes share varied genomic blocks across several amniote lineages. This implies the possible split of an ancestral super-sex chromosome via chromosomal rearrangements. We review the major findings pertaining to sex chromosomal profiles in amniotes and discuss the evolution of an ancestral super-sex chromosome by collating recent evidence sourced mainly from the snake W sex chromosome analysis. We highlight the role of repeat-mediated sex chromosome conformation and present a genomic landscape of snake Z and W chromosomes, which reveals the relative abundance of major repeats, and identifies the expansion of certain transposable elements. The latest revolution in chromosomics, i.e., complete telomere-to-telomere assembly, offers mechanistic insights into the evolutionary origin of sex chromosomes.

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Marec, František, and Walther Traut. "Sex chromosome pairing and sex chromatin bodies in W–Z translocation strains of Ephestia kuehniella (Lepidoptera)." Genome 37, no. 3 (June 1, 1994): 426–35. http://dx.doi.org/10.1139/g94-060.

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Structure and pairing behavior of sex chromosomes in females of four T(W;Z) lines of the Mediterranean flour moth, Ephestia kuehniella, were investigated using light and electron microscopic techniques and compared with the wild type. In light microscopic preparations of pachytene oocytes of wild-type females, the WZ bivalent stands out by its heterochromatic W chromosome strand. In T(W;Z) females, the part of the Z chromosome that was translated onto the W chromosome was demonstrated as a distal segment of the neo-W chromosome, displaying a characteristic non-W chromosomal chromomere–interchromomere pattern. This segment is homologously paired with the corresponding part of a complete Z chromosome. In contrast with the single ball of heterochromatic W chromatin in highly polyploid somatic nuclei of wild-type females, the translocation causes the formation of deformed or fragmented W chromatin bodies, probably owing to opposing tendencies of the Z and W chromosomal parts of the neo-W. In electron microscopic preparations of microspread nuclei, sex chromosome bivalents were identified by the remnants of electron-dense heterochromatin tangles decorating the W chromosome axis, by the different lengths of the Z and W chromosome axes, and by incomplete pairing. No heterochromatin tangles were attached to the translocated segment of the Z chromosome at one end of the neo-W chromosome. Because of the homologous pairing between the translocation and the structurally normal Z chromosome, pairing affinity of sex chromosomes in T(W;Z) females is significantly improved. Specific differences observed among T(W;Z)1–4 translocations are probably due to the different lengths of the translocated segments.Key words: Mediterranean flour moth, sex chromosomes, sex chromatin, translocations, synaptonemal complexes, microspreading.

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Uno, Yoshinobu, Chizuko Nishida, Chiyo Takagi, Takeshi Igawa, Naoto Ueno, Masayuki Sumida, and Yoichi Matsuda. "Extraordinary Diversity in the Origins of Sex Chromosomes in Anurans Inferred from Comparative Gene Mapping." Cytogenetic and Genome Research 145, no. 3-4 (2015): 218–29. http://dx.doi.org/10.1159/000431211.

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Sex determination in frogs (anurans) is genetic and includes both male and female heterogamety. However, the origins of the sex chromosomes and their differentiation processes are poorly known. To investigate diversity in the origins of anuran sex chromosomes, we compared the chromosomal locations of sex-linked genes in 4 species: the African clawed frog (Xenopus laevis), the Western clawed frog (Silurana/X. tropicalis), the Japanese bell-ring frog (Buergeria buergeri), and the Japanese wrinkled frog (Rana rugosa). Comparative mapping data revealed that the sex chromosomes of X. laevis, X. tropicalis and R. rugosa are different chromosome pairs; however, the sex chromosomes of X. tropicalis and B. buergeri are homologous, although this may represent distinct evolutionary origins. We also examined the status of sex chromosomal differentiation in B. buergeri, which possesses heteromorphic ZW sex chromosomes, using comparative genomic hybridization and chromosome painting with DNA probes from the microdissected W chromosome. At least 3 rearrangement events have occurred in the proto-W chromosome: deletion of the nucleolus organizer region and a paracentric inversion followed by amplification of non-W-specific repetitive sequences.

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Hejníčková, Martina, Martina Dalíková, Pavel Potocký, Toomas Tammaru, Marharyta Trehubenko, Svatava Kubíčková, František Marec, and Magda Zrzavá. "Degenerated, Undifferentiated, Rearranged, Lost: High Variability of Sex Chromosomes in Geometridae (Lepidoptera) Identified by Sex Chromatin." Cells 10, no. 9 (August 28, 2021): 2230. http://dx.doi.org/10.3390/cells10092230.

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Sex chromatin is a conspicuous body that occurs in polyploid nuclei of most lepidopteran females and consists of numerous copies of the W sex chromosome. It is also a cytogenetic tool used to rapidly assess the W chromosome presence in Lepidoptera. However, certain chromosomal features could disrupt the formation of sex chromatin and lead to the false conclusion that the W chromosome is absent in the respective species. Here we tested the sex chromatin presence in 50 species of Geometridae. In eight selected species with either missing, atypical, or normal sex chromatin patterns, we performed a detailed karyotype analysis by means of comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). The results showed a high diversity of W chromosomes and clarified the reasons for atypical sex chromatin, including the absence or poor differentiation of W, rearrangements leading to the neo-W emergence, possible association with the nucleolus, and the existence of multiple W chromosomes. In two species, we detected intraspecific variability in the sex chromatin status and sex chromosome constitution. We show that the sex chromatin is not a sufficient marker of the W chromosome presence, but it may be an excellent tool to pinpoint species with atypical sex chromosomes.

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Rutkowska, Joanna, Malgorzata Lagisz, and Shinichi Nakagawa. "The long and the short of avian W chromosomes: no evidence for gradual W shortening." Biology Letters 8, no. 4 (March 14, 2012): 636–38. http://dx.doi.org/10.1098/rsbl.2012.0083.

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The well-established view of the evolution of sex chromosome dimorphism is of a gradual genetic and morphological degeneration of the hemizygous chromosome. Yet, no large-scale comparative analysis exists to support this view. Here, we analysed karyotypes of 200 bird species to test whether the supposed directional changes occur in bird sex chromosomes. We found no support for the view that W chromosomes gradually become smaller over evolutionary time. On the contrary, the length of the W chromosome can fluctuate over short time scales, probably involving both shortening and elongation of non-coding regions. Recent discoveries of near-identical palindromes and neo-sex chromosomes in birds may also contribute to the observed variation. Further studies are now needed to investigate how chromosome morphology relates to its gene content, and whether the changes in size were driven by selection.

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Lisachov, Artem P., Svetlana A. Galkina, Alsu F. Saifitdinova, Svetlana A. Romanenko, Daria A. Andreyushkova, Vladimir A. Trifonov, and Pavel M. Borodin. "Identification of sex chromosomes in Eremias velox (Lacertidae, Reptilia) using lampbrush chromosome analysis." Comparative Cytogenetics 13, no. 2 (May 14, 2019): 17–28. http://dx.doi.org/10.3897/compcytogen.v13i2.34116.

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Reptiles are good objects for studying the evolution of sex determination, since they have different sex determination systems in different lineages. Lacertid lizards have been long-known for possessing ZZ/ZW type sex chromosomes. However, due to morphological uniformity of lacertid chromosomes, the Z chromosome has been only putatively cytologically identified. We used lampbrush chromosome (LBC) analysis and FISH with a W-specific probe in Eremiasvelox (Pallas, 1771) to unequivocally identify the ZW bivalent and investigate its meiotic behavior. The heterochromatic W chromosome is decondensed at the lampbrush stage, indicating active transcription, contrast with the highly condensed condition of the lampbrush W chromosomes in birds. We identified the Z chromosome by its chiasmatic association with the W chromosome as chromosome XIII of the 19 chromosomes in the LBC karyotype. Our findings agree with previous genetic and genomic studies, which suggested that the lacertid Z chromosome should be one of the smaller macrochromosomes.

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Mahony, M. J. "Heteromorphic sex chromosomes in the Australian frog Crinia bilingua (Anura: Myobatrachidae)." Genome 34, no. 3 (June 1, 1991): 334–37. http://dx.doi.org/10.1139/g91-055.

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The karyotype of Crinia bilingua was examined and analysed with standard staining, C-banding, and silver-staining. Heteromorphic sex chromosomes of the ZW ♂/ZZ ♀ type were observed. The larger W chromosome is submetacentric and the smaller Z chromosome is acrocentric. The centromere and proximal region of the short arm of the W chromosome consist of constitutive heterochromatin (C-band region), and beyond this is a small euchromatic terminal region. The centromere of the Z chromosome did not C-band. The long arms of the Z and W chromosomes are euchromatic and equal in length. The nucleolar organiser region occurs terminally on the long arm of both the Z and W chromosomes, and there is no cytological evidence for inactivity of the nucleolar organiser region on the W chromosome. These features indicate an early stage in the evolution of heteromorphic sex chromosomes.Key words: heteromorphic sex chromosomes, frog, Crinia bilingua.

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Scacchetti, Priscilla C., Ricardo Utsunomia, José C. Pansonato-Alves, Marcelo R. Vicari, Roberto F. Artoni, Claudio Oliveira, and Fausto Foresti. "Chromosomal Mapping of Repetitive DNAs in Characidium (Teleostei, Characiformes): Genomic Organization and Diversification of ZW Sex Chromosomes." Cytogenetic and Genome Research 146, no. 2 (2015): 136–43. http://dx.doi.org/10.1159/000437165.

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The speciose neotropical genus Characidium has proven to be a good model for cytogenetic exploration. Representatives of this genus often have a conserved diploid chromosome number; some species exhibit a highly differentiated ZZ/ZW sex chromosome system, while others do not show any sex-related chromosome heteromorphism. In this study, chromosome painting using a W-specific probe and comparative chromosome mapping of repetitive sequences, including ribosomal clusters and 4 microsatellite motifs - (CA)15, (GA)15, (CG)15, and (TTA)10 -, were performed in 6 Characidium species, 5 of which possessed a heteromorphic ZW sex chromosome system. The W-specific probe showed hybridization signals on the W chromosome of all analyzed species, indicating homology among the W chromosomes. Remarkably, a single major rDNA-bearing chromosome pair was found in all species. The 18S rDNA localized to the sex chromosomes in C. lanei, C. timbuiense and C. pterostictum, while the major rDNA localized to one autosome pair in C. vidali and C. gomesi. In contrast, the number of 5S rDNA-bearing chromosomes varied. Notably, minor ribosomal clusters were identified in the W chromosome of C. vidali. Microsatellites were widely distributed across almost all chromosomes of the karyotypes, with a greater accumulation in the subtelomeric regions. However, clear differences in the abundance of each motif were detected in each species. In addition, the Z and W chromosomes showed the differential accumulation of distinct motifs. Our results revealed variability in the distribution of repetitive DNA sequences and their possible association with sex chromosome diversification in Characidium species.

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9

Sharbel, Timothy F., David M. Green, and Andreas Houben. "B-chromosome origin in the endemic New Zealand frog Leiopelma hochstetteri through sex chromosome devolution." Genome 41, no. 1 (February 1, 1998): 14–22. http://dx.doi.org/10.1139/g97-091.

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The endemic New Zealand frog Leiopelma hochstetteri has variable numbers of mitotically stable B chromosomes. To assess whether the B chromosomes were derived from the autosome complement, they were isolated by micromanipulation and their DNA amplified by degenerate oligonucleotide primed PCR. Southern hybridizations of B chromosome DNA probes to genomic DNA from males and females characterized by differing numbers of B chromosomes demonstrated that the B chromosomes were derived from the univalent W sex chromosome characteristic of North Island populations. The presence of homologous B chromosome specific sequences from geographically distinct populations indicates a single origin of the B chromosomes. Furthermore, a primitive homology shared by B chromosomes and the W sex chromosome from an ancestral WZ/ZZ karyotype, which is still present in frogs from Great Barrier Island, shows that the B chromosomes originated soon after the univalent W sex chromosome had originated. Sequence analysis revealed that B chromosome DNA is composed of repeat sequences and has the potential to form stable hairpin structures. The molecular dynamics of these structures may reflect an inherent propensity to undergo rapid change in nucleotide sequence and chromosome structure.

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10

Johnson Pokorná, Martina, Marie Altmanová, Michail Rovatsos, Petr Velenský, Roman Vodička, Ivan Rehák, and Lukáš Kratochvíl. "First Description of the Karyotype and Sex Chromosomes in the Komodo Dragon (Varanus komodoensis)." Cytogenetic and Genome Research 148, no. 4 (2016): 284–91. http://dx.doi.org/10.1159/000447340.

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The Komodo dragon (Varanus komodoensis) is the largest lizard in the world. Surprisingly, it has not yet been cytogenetically examined. Here, we present the very first description of its karyotype and sex chromosomes. The karyotype consists of 2n = 40 chromosomes, 16 macrochromosomes and 24 microchromosomes. Although the chromosome number is constant for all species of monitor lizards (family Varanidae) with the currently reported karyotype, variability in the morphology of the macrochromosomes has been previously documented within the group. We uncovered highly differentiated ZZ/ZW sex microchromosomes with a heterochromatic W chromosome in the Komodo dragon. Sex chromosomes have so far only been described in a few species of varanids including V. varius, the sister species to Komodo dragon, whose W chromosome is notably larger than that of the Komodo dragon. Accumulations of several microsatellite sequences in the W chromosome have recently been detected in 3 species of monitor lizards; however, these accumulations are absent from the W chromosome of the Komodo dragon. In conclusion, although varanids are rather conservative in karyotypes, their W chromosomes exhibit substantial variability at the sequence level, adding further evidence that degenerated sex chromosomes may represent the most dynamic genome part.

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Dissertations / Theses on the topic "W chromosome"

1

Fritsche, Miriam [Verfasser], and Dieter W. [Akademischer Betreuer] Heermann. "Chromosome Kissing and Chromosome Folding in Eukaryotic and Bacterial Cells / Miriam Fritsche ; Betreuer: Dieter W. Heermann." Heidelberg : Universitätsbibliothek Heidelberg, 2011. http://d-nb.info/1179230469/34.

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2

Griffiths, Richard. "The isolation and application of W chromosome derived DNA sequences in the lesser black-backed gull (Larus fuscus)." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293465.

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3

Bonselaar, Jacqueline A. "Expression of the Avian sex-specific gene on the W chromosome in chickens." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0020/MQ47310.pdf.

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Li, Songling [Verfasser], and Dieter W. [Akademischer Betreuer] Heermann. "From Genome-wide Probabilistic Functional Networks to a Model for Physical Chromosome Interactions / Songling Li ; Betreuer: Dieter W. Heermann." Heidelberg : Universitätsbibliothek Heidelberg, 2012. http://d-nb.info/1179785452/34.

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Zhang, Yang [Verfasser], and Dieter W. [Akademischer Betreuer] Heermann. "Chromosomes in Interphase and Mitosis / Yang Zhang ; Betreuer: Dieter W. Heermann." Heidelberg : Universitätsbibliothek Heidelberg, 2014. http://d-nb.info/1177888955/34.

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Jia, Jiying [Verfasser], and Dieter W. [Akademischer Betreuer] Heermann. "Modeling and Study of the Organization of Chromosomes / Jiying Jia ; Betreuer: Dieter W. Heermann." Heidelberg : Universitätsbibliothek Heidelberg, 2019. http://d-nb.info/1200410742/34.

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Santos, Maria Jose Teixeira Fonseca dos. "Estudo da imobilização de SE-30 sobre Chromosorb W-HP atraves de radiação gama." [s.n.], 1990. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249909.

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Orientador : Carol Hollingworth Collins
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-07-13T23:25:54Z (GMT). No. of bitstreams: 1 Santos_MariaJoseTeixeiraFonsecados_M.pdf: 4592179 bytes, checksum: 7043c1b58cbb54c5cdf452c6c85a2e1b (MD5) Previous issue date: 1990
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Facchin, Ileana. "Avaliação do comportamento das fases estacionarias DC-200 e DC-QF-1 sobre chromosorb W sinalizado submetidas a radiação gama." [s.n.], 1990. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249908.

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Orientador : Carol Hollingworth Collins
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-07-14T01:30:26Z (GMT). No. of bitstreams: 1 Facchin_Ileana_M.pdf: 7912694 bytes, checksum: f4c54f5abce6ce4a97f6cb65e14d90d6 (MD5) Previous issue date: 1990
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Türk, Serin [Verfasser], W. [Akademischer Betreuer] Koch, P. [Akademischer Betreuer] Hoppmann, Thomas A. [Akademischer Betreuer] Meitinger, and A. [Akademischer Betreuer] Kastrati. "Ein Hotspot für die koronare Herzkrankheit auf Chromosom 9 : Assoziation ausgewählter Sequenzvariationen mit dem Myokardinfarkt / Serin Türk. Gutachter: Thomas A. Meitinger ; A. Kastrati. Betreuer: P. Hoppmann ; W. Koch." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1025337662/34.

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10

DALÍKOVÁ, Martina. "Využití BAC klonů při studiu pohlavního chromosomu W obaleče jablečného \kur{Cydia pomonella} (Lepidoptera: Tortricidae)." Master's thesis, 2009. http://www.nusl.cz/ntk/nusl-49849.

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In the present study, the W sex-chromosome of the codling moth was studied by means of fluorescence in situ hybridization (FISH) with probes prepared from bacterial artificial chromosome (BAC), which were isolated from the codling moth BAC library. The BAC library was screened for clones derived from both the W and Z sex chromosomes using three sets of molecular markers of codling moth sex chromosomes. A total of 54 BAC clones have been obtained. In this work, only 3 W-derived BAC clones and 1 Z-derived BAC clone were further characterized by BAC-FISH mapping on chromosome preparations of pachytene oocytes; the other BAC clones have been retained for next studies. Whereas the Z-BAC probe provided a discrete hybridization signal on the Z chromosome, and surprisingly on the W chromosome, the W-BAC probes showed multiple hybridization signals distributed on the whole W chromosome, suggesting that they are mainly composed of repetitive sequences, which occur in multiple clusters on the W chromosome. The specific pattern of W-BAC hybridization signals along with the discrete signal of the Z-BAC enabled us to discriminate left/right orientation of both the W and Z chromosomes and examine specificity of W-Z pairing during meiotic prophase I.

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Books on the topic "W chromosome"

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International Conference on Environmental Mutagens in Human Populations (2nd 1995 Prague, Czech Republic). Second International Conference on Environmental Mutagens in Human Populations: August 20-25, 1995, Prague, Czech Republic / sponsored by Prague Institute of Advanced Studies, Regional Institute of Hygiene of Central Bohemia, University of Texas Medical Branch ; co-editors, William W. Au, Radim J. Sram ; assistant editor, Sherif Abdel-Rahman. Research Triangle Park, NC: U.S. Dept. of Health and Human Services, Public Health Service, National Institutes of Health, National Institute of Environmental Health Sciences, 1996.

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1944-, Adolph Kenneth W., ed. Gene and chromosome analysis: Edited by Kenneth W. Adolph. San Diego: Academic Press, 1993.

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Ratcliffe. Prospective Studies Child W/sex Chromo (Prospective Studies on Children with Sex Chromosome Aneuploi). WILEY-LISS, 1986.

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Book chapters on the topic "W chromosome"

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"W Chromosome." In Encyclopedia of Genetics, Genomics, Proteomics and Informatics, 2095. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6754-9_18088.

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Burt, D. W. "W Chromosome." In Encyclopedia of Genetics, 2125. Elsevier, 2001. http://dx.doi.org/10.1006/rwgn.2001.1384.

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Pita, M. "W Chromosome." In Brenner's Encyclopedia of Genetics, 313–14. Elsevier, 2013. http://dx.doi.org/10.1016/b978-0-12-374984-0.01636-3.

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Marec, Franti_ek, Ken Sahara, and Walther Traut. "Rise and Fall of the W Chromosome in Lepidoptera." In Molecular Biology and Genetics of the Lepidoptera. CRC Press, 2009. http://dx.doi.org/10.1201/9781420060201-c3.

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"Rise and Fall of the W Chromosome in Lepidoptera." In Molecular Biology and Genetics of the Lepidoptera, 65–80. CRC Press, 2009. http://dx.doi.org/10.1201/9781420060201-7.

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"Genetic Principles." In DNA Fingerprinting, edited by Lorne t. Kirby. Oxford University Press, 1993. http://dx.doi.org/10.1093/oso/9780716770015.003.0005.

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Genetics is the study of heredity. Each individual’s makeup, or phenotype, is determined by nature and modified by environmental factors. DNA identity analysis is based strictly on heredity, and only in the rare case where a human had a bone marrow transplant would the white blood cell genotype differ from that inherited. Difficulties can arise with specimens because of DNA degradation or contamination by extraneous materials, and mixed cell populations could be present in tumorous tissue. The analyst must always be cognizant of these complicating factors. The concept of the gene was advanced by the Moravian monk Gregor Mendel in 1865 based on observations he made after crossing different varieties of garden peas; these experiments are considered the beginning of the discipline of genetics. (The term gene was actually coined by the Danish plant scientist W. Johannsen in the early 1900s.) Mendel formulated two laws. The law of segregation or separation states that two members of each gene pair (alleles) in a diploid organism separate to different gametes during sex cell formation. The law of independent assortment states that members of different pairs of alleles, if located on separate chromosomes or far apart on the same homologous chromosome pair, assort independently into gametes. These laws are basic to the understanding of biological family relationships and play a critical role in such contemporary issues as paternity testing and immigration disputes. The basic unit of life is the cell. Cells are microfactories in which raw materials (amino acids, simple carbohydrates, lipids, and trace elements) are received, new substances (proteins, complex lipids, carbohydrates, and nucleic acids) are produced, and wastes are removed. The thousands of different enzymes required for the myriad ongoing chemical reactions are key to the efficient functioning of cells. Each cell has the ability to self-replicate using the deoxyribonucleic acid (DNA) code as the blueprint, raw materials as building blocks, and enzymes as catalysts. It has been estimated that the average human being is composed of approximately 100 trillion cells—a considerable amount of DNA.

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