Read by QxMD icon Read

y chromosome evolution

William J Gammerdinger, Matthew A Conte, Jean-François Baroiller, Helena D'Cotta, Thomas D Kocher
BACKGROUND: Inversions and other structural polymorphisms often reduce the rate of recombination between sex chromosomes, making it impossible to fine map sex-determination loci using traditional genetic mapping techniques. Here we compare distantly related species of tilapia that each segregate an XY system of sex-determination on linkage group 1. We use whole genome sequencing to identify shared sex-patterned polymorphisms, which are candidates for the ancestral sex-determination mutation...
October 18, 2016: BMC Genomics
Mitzi I Kuroda, Andres Hilfiker, John C Lucchesi
The sex chromosomes have special significance in the history of genetics. The chromosomal basis of inheritance was firmly established when Calvin Bridges demonstrated that exceptions to Mendel's laws of segregation were accompanied at the cytological level by exceptional sex chromosome segregation. The morphological differences between X and Y exploited in Bridges' experiments arose as a consequence of the evolution of the sex chromosomes. Originally a homologous chromosome pair, the degeneration of the Y chromosome has been accompanied by a requirement for increased expression of the single X chromosome in males...
October 2016: Genetics
R C R Noronha, L M R Barros, R E F Araújo, D F Marques, C Y Nagamachi, C Martins, J C Pieczarka
BACKGROUND: Cytogenetic studies were conducted in the Brazilian Amazon turtles, Podocnemis expansa Schweigger, 1912 (PEX) and Podocnemis unifilis Troschel, 1848 (PUN) to understand their karyoevolution. Their chromosomal complements were compared using banding techniques (C, G-, Ag-NOR and Chromomycin A3) and fluorescence in situ hybridization (FISH), and efforts were made to establish evolutionary chromosomal relationships within the Podocnemidae family. RESULTS: Our results revealed that both species have a chromosome complement of 2n = 28...
2016: Molecular Cytogenetics
X Cheng, Y Xiong, D H Li, J Cheng, Y P Cao, C C Yan, Q Jin, N Sun, Y P Cai, Y Lin
With high nutritional value in its fruits, Dangshan Su pear has been widely cultivated in China. The stone cell content in fruits is a key factor affecting fruit quality in pear, and the formation of stone cells has been associated with lignin biosynthesis. O-Methyltransferase (OMT) is a key enzyme involved in lignin metabolism within the phenylpropanoid pathway. Here, we screened 26 OMT genes from the Pyrus bretschneideri cv. Dangshan Su genome using the DNATOOLs software. To characterize the OMT gene family in pear, gene structure, chromosomal localization, and conserved motifs of PbOMTs were analyzed...
September 2, 2016: Genetics and Molecular Research: GMR
Sebastián Pita, Francisco Panzera, Antonio Sánchez, Teresa Palomeque, Pedro Lorite
In order to provide a broad picture on the origin and evolution of holocentric X chromosomes in heteropteran species, we prepared a sex chromosome painting probe by microdissection of the X1 and X2 chromosomes from a kissing bug Mepraia spinolai (Hemiptera: Reduviidae: Triatominae). Fluorescence in situ hybridization on four species of the Triatomini having different amounts of autosomal heterochromatin and sex chromosome systems show that the Xs probe hybridizes on the euchromatin, located both on autosomes and X chromosomes...
September 29, 2016: Journal of Medical Entomology
Xiaoshu Chen, Jianzhi Zhang
Ohno proposed that the expression levels of X-linked genes have been doubled to compensate the degeneration of Y-linked homologs during the evolution of mammalian sex chromosomes, but RNA sequencing in human somatic tissues showed no such upregulation for the vast majority of X-linked genes. Here we report that the X to autosome expression ratio equals ~1 in haploid human parthenogenetic embryonic stem (pES) cells and ~0.5 in diploidized pES cells, both with one active X chromosome. Although we confirmed the upregulation of ~5% of X-linked genes encoding members of large protein complexes in diploids, these genes are also upregulated in haploids, breaking the otherwise balanced dosage...
September 4, 2016: Molecular Biology and Evolution
Jasdeep Kaur Dhanoa, Chandra Sekhar Mukhopadhyay, Jaspreet Singh Arora
The mammalian sex-chromosomes (X and Y) have evolved from autosomes and are involved in sex determination and reproductive traits. The Y-chromosome is the smallest chromosome that consists of 2-3% of the haploid genome and may contain between 70 and 200 genes. The Y-chromosome plays major role in male fertility and is suitable to study the evolutionary relics, speciation, and male infertility and/or subfertility due to its unique features such as long non-recombining region, abundance of repetitive sequences, and holandric inheritance pattern...
July 2016: Veterinary World
X Y Song, Y Y Zhang, F C Wu, L Zhang
Cysteine-rich polycomb-like (CPP) proteins are members of a small family of transcription factors, which have been identified and characterized in Arabidopsis, rice, and soybean. In this study, we investigated CPP-like genes in the maize genome. The results revealed 13 putative CPP-like genes, which were found to encode 17 distinct transcripts and were distributed unequally on 7 of 10 maize chromosomes. Analysis of phylogenetic relationships showed that Arabidopsis, rice, and maize CPP-like transcription factors can be grouped into two subfamilies...
2016: Genetics and Molecular Research: GMR
Elkin Y Suárez-Villota, Ronie E Haro, Rodrigo A Vargas, Milton H Gallardo
BACKGROUND: The low-numbered 14-chromosome karyotype of marsupials has falsified the fusion hypothesis claiming ancestrality from a 22-chromosome karyotype. Since the 14-chromosome condition of the relict Dromiciops gliroides is reminecent of ancestrality, its interstitial traces of past putative fusions and heterochromatin banding patterns were studied and added to available marsupials' cytogenetic data. Fluorescent in situ hybridization (FISH) and self-genomic in situ hybridization (self-GISH) were used to detect telomeric and repetitive sequences, respectively...
2016: Molecular Cytogenetics
Yoram Yagil, Barak Markus, Refael Kohen, Chana Yagil
We investigated the pathophysiology of diet-induced diabetes in the Cohen diabetic rat (CDs/y) from its induction to its chronic phase, using a multi-layered integrated genomic approach. We identified by linkage analysis two diabetes-related quantitative trait loci on RNO4 and RNO13. We determined their functional contribution to diabetes by chromosomal substitution, using congenic and consomic strains. To identify within these loci genes of relevance to diabetes, we sequenced the genome of CDs/y and compared it to 25 other rat strains...
July 26, 2016: Molecular Medicine
Eugenia E Montiel, Daleen Badenhorst, Ling S Lee, Robert Literman, Vladimir Trifonov, Nicole Valenzuela
Turtle karyotypes are highly conserved compared to other vertebrates; yet, variation in diploid number (2n = 26-68) reflects profound genomic reorganization, which correlates with evolutionary turnovers in sex determination. We evaluate the published literature and newly collected comparative cytogenetic data (G- and C-banding, 18S-NOR, and telomere-FISH mapping) from 13 species spanning 2n = 28-68 to revisit turtle genome evolution and sex determination. Interstitial telomeric sites were detected in multiple lineages that underwent diploid number and sex determination turnovers, suggesting chromosomal rearrangements...
2016: Cytogenetic and Genome Research
Guray Kuzu, Emily G Kaye, Jessica Chery, Trevor Siggers, Lin Yang, Jason R Dobson, Sonia Boor, Jacob Bliss, Wei Liu, Gerwald Jogl, Remo Rohs, Nadia D Singh, Martha L Bulyk, Michael Y Tolstorukov, Erica Larschan
Dosage compensation is an essential process that equalizes transcript levels of X-linked genes between sexes by forming a domain of coordinated gene expression. Throughout the evolution of Diptera, many different X-chromosomes acquired the ability to be dosage compensated. Once each newly evolved X-chromosome is targeted for dosage compensation in XY males, its active genes are upregulated two-fold to equalize gene expression with XX females. In Drosophila melanogaster, the CLAMP zinc finger protein links the dosage compensation complex to the X-chromosome...
July 2016: PLoS Genetics
José Miguel García Sagredo
Here we report the results of prenatal diagnosis at the Hospital Universitario Ramón y Cajal since its opening in 1979 to 2010, establishing a parallelism between the different methodologies for screening and prenatal diagnosis, clinical indications, and demographic changes. It shows how the indications have varied as to the structure of the population did. These changes have been possible thanks to the fact that the screening and prenatal diagnosis methods have allowed it. Demonstrating, once again, how procedures evolve with technology and adapt to the demography...
2014: Anales de la Real Academia Nacional de Medicina
Stanley K Sessions, Lilijana Bizjak Mali, David M Green, Vladimir Trifonov, Malcolm Ferguson-Smith
A major goal of genomic and reproductive biology is to understand the evolution of sex determination and sex chromosomes. Species of the 2 genera of the Salamander family Proteidae - Necturus of eastern North America, and Proteus of Southern Europe - have similar-looking karyotypes with the same chromosome number (2n = 38), which differentiates them from all other salamanders. However, Necturus possesses strongly heteromorphic X and Y sex chromosomes that Proteus lacks. Since the heteromorphic sex chromosomes of Necturus were detectable only with C-banding, we hypothesized that we could use C-banding to find sex chromosomes in Proteus...
2016: Cytogenetic and Genome Research
Jennifer A M Graves
Comparative mapping and sequencing show that turnover of sex determining genes and chromosomes, and sex chromosome rearrangements, accompany speciation in many vertebrates. Here I review the evidence and propose that the evolution of therian mammals was precipitated by evolution of the male-determining SRY gene, defining a novel XY sex chromosome pair, and interposing a reproductive barrier with the ancestral population of synapsid reptiles 190 million years ago (MYA). Divergence was reinforced by multiple translocations in monotreme sex chromosomes, the first of which supplied a novel sex determining gene...
August 2016: BioEssays: News and Reviews in Molecular, Cellular and Developmental Biology
Yeşim Doğan Alakoç, Nejat Akar
Before analysis of DNA from ancient remains was possible, anthropologists studied evolution and migration patterns using data obtained from population genetic studies on modern populations combined with data obtained from morphological evaluations of ancient remains. Currently, DNA analysis of ancient populations is making a valuable contribution to these efforts. Researchers that perform ancient DNA analysis prefer to study polymorphisms on the Y chromosome or mitochondrial DNA because the results are easier to statistically evaluate...
December 5, 2011: Turkish Journal of Haematology: Official Journal of Turkish Society of Haematology
Tomotaka Matsumoto, Jun Kitano
Sex chromosomes are among the most evolutionarily labile features in some groups of animals. One of the mechanisms causing structural changes of sex chromosomes is fusion with an autosome. A recent study showed that the establishment rates of Y chromosome-autosome fusions are much higher than those of other fusions (i.e., X-autosome, W-autosome, and Z-autosome fusions) in fishes and reptiles. Although sexually antagonistic selection may be one of the most important driving forces of sex chromosome-autosome fusions, a previous theoretical analysis showed that sexually antagonistic selection alone cannot explain the excess of Y-autosome fusions in these taxa...
September 7, 2016: Journal of Theoretical Biology
Ester Borras, F Anthony San Lucas, Kyle Chang, Ruoji Zhou, Gita Masand, Jerry Fowler, Maureen E Mork, Y Nancy You, Melissa W Taggart, Florencia McAllister, David A Jones, Gareth E Davies, Winfried Edelmann, Erik A Ehli, Patrick M Lynch, Ernest T Hawk, Gabriel Capella, Paul Scheet, Eduardo Vilar
The molecular basis of the adenoma-to-carcinoma transition has been deduced using comparative analysis of genetic alterations observed through the sequential steps of intestinal carcinogenesis. However, comprehensive genomic analyses of adenomas and at-risk mucosa are still lacking. Therefore, our aim was to characterize the genomic landscape of colonic at-risk mucosa and adenomas. We analyzed the mutation profile and copy number changes of 25 adenomas and adjacent mucosa from 12 familial adenomatous polyposis patients using whole-exome sequencing and validated allelic imbalances (AI) in 37 adenomas using SNP arrays...
June 2016: Cancer Prevention Research
Alexander G Bugrov, Ilyas E Jetybayev, Gayane H Karagyan, Nicolay B Rubtsov
Although previous cytogenetic analysis of Pamphagidae grasshoppers pointed to considerable karyotype uniformity among most of the species in the family, our study of species from Armenia has discovered other, previously unknown karyotypes, differing from the standard for Pamphagidae mainly in having unusual sets of sex chromosomes. Asiotmethis turritus (Fischer von Waldheim, 1833), Paranocaracris rubripes (Fischer von Waldheim, 1846), and Nocaracris cyanipes (Fischer von Waldheim, 1846) were found to have the karyotype 2n♂=16+neo-XY and 2n♀=16+neo-XX, the neo-X chromosome being the result of centromeric fusion of an ancient acrocentric X chromosome and a large acrocentric autosome...
2016: Comparative Cytogenetics
Massimo Iorizzo, Shelby Ellison, Douglas Senalik, Peng Zeng, Pimchanok Satapoomin, Jiaying Huang, Megan Bowman, Marina Iovene, Walter Sanseverino, Pablo Cavagnaro, Mehtap Yildiz, Alicja Macko-Podgórni, Emilia Moranska, Ewa Grzebelus, Dariusz Grzebelus, Hamid Ashrafi, Zhijun Zheng, Shifeng Cheng, David Spooner, Allen Van Deynze, Philipp Simon
We report a high-quality chromosome-scale assembly and analysis of the carrot (Daucus carota) genome, the first sequenced genome to include a comparative evolutionary analysis among members of the euasterid II clade. We characterized two new polyploidization events, both occurring after the divergence of carrot from members of the Asterales order, clarifying the evolutionary scenario before and after radiation of the two main asterid clades. Large- and small-scale lineage-specific duplications have contributed to the expansion of gene families, including those with roles in flowering time, defense response, flavor, and pigment accumulation...
June 2016: Nature Genetics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"