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1.
Proc Natl Acad Sci U S A ; 119(19): e2119382119, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35512091

RESUMO

SignificanceIt is increasingly recognized that sex chromosomes are not only the battlegrounds between sexes but also the Great Walls fencing off introgression between diverging lineages. Here we dissect the multifaceted roles of sex chromosomes using experimental evolution, whole-genome resequencing, and theoretical modeling, taking advantage of hybrid populations between a Drosophila sister species pair in the early stage of speciation that have different sex chromosome systems. Our work sheds light onto the complex roles of neo-sex chromosome evolution in creating a sex-dependent asymmetrical introgression barrier at a species boundary, and we show how diverse population genetic forces act in concert to explain observed patterns of introgression across the genome.


Assuntos
Cromossomos Sexuais , Cromossomo Y , Animais , Drosophila/genética , Evolução Molecular , Cromossomos Sexuais/genética
2.
Genes (Basel) ; 13(4)2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35456419

RESUMO

Mitochondrial DNA and nonrecombinant parts of Y-chromosome DNA are a great tool for looking at a species' past. They are inherited for generations almost unaffected because they do not participate in recombination; thus, the time of occurrence of each mutation can be estimated based on the average mutation rate. Thanks to this, male and female haplogroups guide confirming events in the distant past (potential centers of domestication, settlement of areas, trade connections) as well as in modern breeding (crossbreeding, confirmation of paternity). This research focuses mainly on the development of domestic sheep and its post-domestication expansion, which has occurred through human trade from one continent to another. So far, five mitochondrial and five Y-chromosome haplogroups and dozens of their haplotypes have been detected in domestic sheep through studies worldwide. Mitochondrial DNA variability is more or less correlated with distance from the domestication center, but variability on the recombinant region of the Y chromosome is not. According to available data, central China shows the highest variability of male haplogroups and haplotypes.


Assuntos
Domesticação , Variação Genética , Animais , DNA Mitocondrial/genética , Feminino , Haplótipos/genética , Masculino , Filogenia , Ovinos/genética , Cromossomo Y/genética
3.
Cells ; 11(7)2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35406682

RESUMO

The conspicuous colour sexual dimorphism of guppies has made them paradigmatic study objects for sex-linked traits and sex chromosome evolution. Both the X- and Y-chromosomes of the common guppy (Poecilia reticulata) are genetically active and homomorphic, with a large homologous part and a small sex specific region. This feature is considered to emulate the initial stage of sex chromosome evolution. A similar situation has been documented in the related Endler's and Oropuche guppies (P. wingei, P. obscura) indicating a common origin of the Y in this group. A recent molecular study in the swamp guppy (Micropoecilia. picta) reported a low SNP density on the Y, indicating Y-chromosome deterioration. We performed a series of cytological studies on M. picta to show that the Y-chromosome is quite small compared to the X and has accumulated a high content of heterochromatin. Furthermore, the Y-chromosome stands out in displaying CpG clusters around the centromeric region. These cytological findings evidently illustrate that the Y-chromosome in M. picta is indeed highly degenerated. Immunostaining for SYCP3 and MLH1 in pachytene meiocytes revealed that a substantial part of the Y remains associated with the X. A specific MLH1 hotspot site was persistently marked at the distal end of the associated XY structure. These results unveil a landmark of a recombining pseudoautosomal region on the otherwise strongly degenerated Y chromosome of M. picta. Hormone treatments of females revealed that, unexpectedly, no sexually antagonistic color gene is Y-linked in M. picta. All these differences to the Poecilia group of guppies indicate that the trajectories associated with the evolution of sex chromosomes are not in parallel.


Assuntos
Ciprinodontiformes , Poecilia , Animais , Ciprinodontiformes/genética , Feminino , Masculino , Poecilia/genética , Cromossomos Sexuais/genética , Áreas Alagadas , Cromossomo Y/genética
4.
Cell Rep ; 39(2): 110636, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35417719

RESUMO

Genetic networks are characterized by extensive buffering. During tumor evolution, disruption of functional redundancies can create de novo vulnerabilities that are specific to cancer cells. Here, we systematically search for cancer-relevant paralog interactions using CRISPR screens and publicly available loss-of-function datasets. Our analysis reveals >2,000 candidate dependencies, several of which we validate experimentally, including CSTF2-CSTF2T, DNAJC15-DNAJC19, FAM50A-FAM50B, and RPP25-RPP25L. We provide evidence that RPP25L can physically and functionally compensate for the absence of RPP25 as a member of the RNase P/MRP complexes in tRNA processing. Our analysis also reveals unexpected redundancies between sex chromosome genes. We show that chrX- and chrY-encoded paralogs, such as ZFX-ZFY, DDX3X-DDX3Y, and EIF1AX-EIF1AY, are functionally linked. Tumor cell lines from male patients with loss of chromosome Y become dependent on the chrX-encoded gene. We propose targeting of chrX-encoded paralogs as a general therapeutic strategy for human tumors that have lost the Y chromosome.


Assuntos
Neoplasias , Oncogenes , RNA Helicases DEAD-box/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Masculino , Antígenos de Histocompatibilidade Menor/metabolismo , Neoplasias/genética , Proteínas de Ligação a RNA/genética , Cromossomos Sexuais/metabolismo , Cromossomo X , Cromossomo Y
5.
Int J Mol Sci ; 23(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35457001

RESUMO

The Y chromosome is one of the sex chromosomes found in males of animals of different taxa, including insects and mammals. Among all chromosomes, the Y chromosome is characterized by a unique chromatin landscape undergoing dynamic evolutionary change. Being entirely heterochromatic, the Y chromosome as a rule preserves few functional genes, but is enriched in tandem repeats and transposons. Due to difficulties in the assembly of the highly repetitive Y chromosome sequence, deep analyses of Y chromosome evolution, structure, and functions are limited to a few species, one of them being Drosophila melanogaster. Despite Y chromosomes exhibiting high structural divergence between even closely related species, Y-linked genes have evolved convergently and are mainly associated with spermatogenesis-related activities. This indicates that male-specific selection is a dominant force shaping evolution of Y chromosomes across species. This review presents our analysis of current knowledge concerning Y chromosome functions, focusing on recent findings in Drosophila. Here we dissect the experimental and bioinformatics data about the Y chromosome accumulated to date in Drosophila species, providing comparative analysis with mammals, and discussing the relevance of our analysis to a wide range of eukaryotic organisms, including humans.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Drosophila/genética , Drosophila melanogaster/genética , Masculino , Mamíferos/genética , Modelos Biológicos , Sequências Repetitivas de Ácido Nucleico , Cromossomo Y/genética
6.
Sci Rep ; 12(1): 5312, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351918

RESUMO

Our exploration of the genetic constitution of Nuku Hiva (n = 51), Hiva Oa (n = 28) and Tahuata (n = 8) of the Marquesas Archipelago based on the analyses of genome-wide autosomal markers as well as high-resolution genotyping of paternal and maternal lineages provides us with information on the origins and settlement of these islands at the fringe of the Austronesian expansion. One widespread theme that emerges from this study is the genetic uniformity and relative isolation exhibited by the Marquesas and Society populations. This genetic homogeneity within East Polynesia groups is reflected in their limited average heterozygosity, uniformity of constituents in the Structure analyses, reiteration of complete mtDNA sequences, marked separation from Asian and other Oceanic populations in the PC analyses, limited differentiation in the PCAs and large number of IBD segments in common. Both the f3 and the Outgroup f3 results provide indications of intra-East Polynesian gene flow that may have promoted the observed intra-East Polynesia genetic homogeneity while ALDER analyses indicate that East Polynesia experienced two gene flow episodes, one relatively recent from Europe that coincides roughly with the European incursion into the region and an early one that may represent the original settlement of the islands by Austronesians. Median Network analysis based on high-resolution Y-STR loci under C2a-M208 generates a star-like topology with East Polynesian groups (especially from the Society Archipelago) in central stem positions and individuals from the different populations radiating out one mutational step away while several Samoan and outlier individuals occupy peripheral positions. This arrangement of populations is congruent with dispersals of C2a-M208 Y chromosomes from East Polynesia as a migration hub signaling dispersals in various directions. The equivalent ages of the C2a-M208 lineage of the populations in the Network corroborate an east to west flow of the most abundant Polynesian Y chromosome.


Assuntos
DNA Mitocondrial , Fluxo Gênico , DNA Mitocondrial/genética , Haplótipos/genética , Humanos , Polinésia , Cromossomo Y
7.
Proc Biol Sci ; 289(1971): 20212645, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35291838

RESUMO

Teleosts are important models to study sex chromosomes and sex-determining (SD) genes because they present a variety of sex determination systems. Here, we used Nanopore and Hi-C technologies to generate a high-contiguity chromosome-level genome assembly of a YY southern catfish (Silurus meridionalis). The assembly is 750.0 Mb long, with contig N50 of 15.96 Mb and scaffold N50 of 27.22 Mb. We also sequenced and assembled an XY male genome with a size of 727.2 Mb and contig N50 of 13.69 Mb. We identified a candidate SD gene through comparisons to our previous assembly of an XX individual. By resequencing male and female pools, we characterized a 2.38 Mb sex-determining region (SDR) on Chr24. Analysis of read coverage and comparison of the X and Y chromosome sequences showed a Y specific insertion (approx. 500 kb) in the SDR which contained a male-specific duplicate of amhr2 (named amhr2y). amhr2y and amhr2 shared high-nucleotide identity (81.0%) in the coding region but extremely low identity in the promotor and intron regions. The exclusive expression in the male gonadal primordium and loss-of-function inducing male to female sex reversal confirmed the role of amhr2y in male sex determination. Our study provides a new example of amhr2 as the SD gene in fish and sheds light on the convergent evolution of the duplication of AMH/AMHR2 pathway members underlying the evolution of sex determination in different fish lineages.


Assuntos
Peixes-Gato , Animais , Peixes-Gato/genética , Mapeamento Cromossômico , Feminino , Genoma , Masculino , Filogenia , Cromossomos Sexuais , Cromossomo Y/genética
8.
Lab Anim (NY) ; 51(2): 42, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35110723
9.
PLoS Genet ; 18(2): e1010040, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35130272

RESUMO

During meiotic prophase I, homologous chromosomes pair, synapse and recombine in a tightly regulated process that ensures the generation of genetically variable haploid gametes. Although the mechanisms underlying meiotic cell division have been well studied in model species, our understanding of the dynamics of meiotic prophase I in non-traditional model mammals remains in its infancy. Here, we reveal key meiotic features in previously uncharacterised marsupial species (the tammar wallaby and the fat-tailed dunnart), plus the fat-tailed mouse opossum, with a focus on sex chromosome pairing strategies, recombination and meiotic telomere homeostasis. We uncovered differences between phylogroups with important functional and evolutionary implications. First, sex chromosomes, which lack a pseudo-autosomal region in marsupials, had species specific pairing and silencing strategies, with implications for sex chromosome evolution. Second, we detected two waves of γH2AX accumulation during prophase I. The first wave was accompanied by low γH2AX levels on autosomes, which correlated with the low recombination rates that distinguish marsupials from eutherian mammals. In the second wave, γH2AX was restricted to sex chromosomes in all three species, which correlated with transcription from the X in tammar wallaby. This suggests non-canonical functions of γH2AX on meiotic sex chromosomes. Finally, we uncover evidence for telomere elongation in primary spermatocytes of the fat-tailed dunnart, a unique strategy within mammals. Our results provide new insights into meiotic progression and telomere homeostasis in marsupials, highlighting the importance of capturing the diversity of meiotic strategies within mammals.


Assuntos
Pareamento Cromossômico/fisiologia , Cromossomos Sexuais/fisiologia , Telômero/fisiologia , Animais , Macropodidae/genética , Marsupiais/genética , Meiose/genética , Meiose/fisiologia , Prófase Meiótica I/fisiologia , Gambás/genética , Cromossomos Sexuais/genética , Telômero/genética , Cromossomo X/genética , Cromossomo Y/genética
10.
PLoS Genet ; 18(2): e1010011, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35134055

RESUMO

Atlantic Halibut (Hippoglossus hippoglossus) has a X/Y genetic sex determination system, but the sex determining factor is not known. We produced a high-quality genome assembly from a male and identified parts of chromosome 13 as the Y chromosome due to sequence divergence between sexes and segregation of sex genotypes in pedigrees. Linkage analysis revealed that all chromosomes exhibit heterochiasmy, i.e. male-only and female-only meiotic recombination regions (MRR/FRR). We show that FRR/MRR intervals differ in nucleotide diversity and repeat class content and that this is true also for other Pleuronectidae species. We further show that remnants of a Gypsy-like transposable element insertion on chr13 promotes early male specific expression of gonadal somatic cell derived factor (gsdf). Less than 4.5 MYA, this male-determining element evolved on an autosomal FRR segment featuring pre-existing male meiotic recombination barriers, thereby creating a Y chromosome. Our findings indicate that heterochiasmy may facilitate the evolution of genetic sex determination systems relying on linkage of sexually antagonistic loci to a sex-determining factor.


Assuntos
Proteínas de Peixes/genética , Linguado/genética , Recombinação Genética , Processos de Determinação Sexual , Animais , Elementos de DNA Transponíveis , Embrião não Mamífero , Feminino , Linguado/embriologia , Expressão Gênica , Genoma , Masculino , Meiose , Regiões Promotoras Genéticas , Sequências Repetitivas de Ácido Nucleico , Cromossomos Sexuais , Cromossomo Y
11.
Science ; 375(6581): 663-666, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35143289

RESUMO

Current theory proposes that degenerated sex chromosomes-such as the mammalian Y-evolve through three steps: (i) recombination arrest, linking male-beneficial alleles to the Y chromosome; (ii) Y degeneration, resulting from the inefficacy of selection in the absence of recombination; and (iii) dosage compensation, correcting the resulting low expression of X-linked genes in males. We investigate a model of sex chromosome evolution that incorporates the coevolution of cis and trans regulators of gene expression. We show that the early emergence of dosage compensation favors the maintenance of Y-linked inversions by creating sex-antagonistic regulatory effects. This is followed by degeneration of these nonrecombining inversions caused by regulatory divergence between the X and Y chromosomes. In contrast to current theory, the whole process occurs without any selective pressure related to sexual dimorphism.


Assuntos
Evolução Molecular , Regulação da Expressão Gênica , Modelos Genéticos , Recombinação Genética , Caracteres Sexuais , Cromossomo Y/genética , Animais , Inversão Cromossômica , Compensação de Dosagem (Genética) , Feminino , Aptidão Genética , Masculino , Seleção Genética , Cromossomo X/genética
13.
Aging Cell ; 21(3): e13563, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35120273

RESUMO

In view of the sex differences in aging-related diseases, sex chromosomes may play a critical role during aging process. This study aimed to identify age-related DNA methylation changes on Y chromosome (ChrY). A two-stage study design was conducted in this study. The discovery stage contained 419 Chinese males, including 205 from the Wuhan-Zhuhai cohort panel, 107 from the coke oven workers panel, and 107 from the Shiyan panel. The validation stage contained 587 Chinese males from the Dongfeng-Tongji sub-cohort. We used the Illumina HumanMethylation BeadChip to determine genome-wide DNA methylation in peripheral blood of the study participants. The associations between age and methylation levels of ChrY CpGs were investigated by using linear regression models with adjustment for potential confounders. Further, associations of age-related ChrY CpGs with all-cause mortality were tested in the validation stage. We identified the significant associations of 41 ChrY CpGs with age at false discovery rate (FDR) <0.05 in the discovery stage, and 18 of them were validated in the validation stage (p < 0.05). Meta-analysis of both stages confirmed the robust positive associations of 14 CpGs and negative associations of 4 CpGs with age (FDR<0.05). Among them, cg03441493 and cg17816615 were significantly associated with all-cause mortality risk [HR(95% CI) = 1.37 (1.04, 1.79) and 0.70 (0.54, 0.93), respectively]. Our results highlighted the importance of ChrY CpGs on male aging.


Assuntos
Metilação de DNA , Epigênese Genética , China , Ilhas de CpG , Metilação de DNA/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Cromossomo Y
14.
Blood Adv ; 6(6): 1895-1903, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35108728

RESUMO

The graft-versus-leukemia (GVL) effect is one of the curative mechanisms of allogeneic hematopoietic stem cell transplantation (allo-HCT). H-Y antigens, which are encoded by Y chromosome, are important targets of the GVL effect. Thus, deletion of the Y chromosome (del[Y]) might cause the GVL effect to deteriorate in a transplantation involving a female donor and male recipient, although the clinical significance of the del(Y) group remains to be elucidated. In this study, we evaluated adult male patients who underwent allo-HCT between 2010 and 2019 in Japan. There were 155 cases in the del(Y) group and 4149 cases without del(Y) who underwent female-to-male allo-HCT. Del(Y) was significantly associated with inferior overall survival (hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.00-1.53; P = .049) and an increased risk of relapse (HR, 1.40; 95% CI, 1.08-1.80; P = .0098) in multivariate analyses. There was no significant difference in nonrelapse mortality between recipients with and without del(Y) (HR, 1.08; 95% CI, 0.769-1.51; P = .67). In contrast, del(Y) was not significantly associated with any clinical outcomes in the cohort of male-to-male allo-HCT. A higher incidence of relapse might have been caused by attenuation of the GVL effect resulting from a lack of H-Y antigens. Because a GVL effect resulting from sex mismatch may not be expected in men with del(Y) who undergo allo-HCT with a female donor, additional post-allo-HCT strategies might be required to prevent disease relapse.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Adulto , Feminino , Efeito Enxerto vs Leucemia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Recidiva , Doadores de Tecidos , Cromossomo Y
15.
Genes (Basel) ; 13(2)2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35205275

RESUMO

The Y chromosome is a valuable genetic marker for studying the origin and influence of paternal lineages in populations. In this study, we conducted Y-chromosomal lineage-tracing in Arabian horses. First, we resolved a Y haplotype phylogeny based on the next generation sequencing data of 157 males from several breeds. Y-chromosomal haplotypes specific for Arabian horses were inferred by genotyping a collection of 145 males representing most Arabian sire lines that are active around the globe. These lines formed three discrete haplogroups, and the same haplogroups were detected in Arabian populations native to the Middle East. The Arabian haplotypes were clearly distinct from the ones detected in Akhal Tekes, Turkoman horses, and the progeny of two Thoroughbred foundation sires. However, a haplotype introduced into the English Thoroughbred by the stallion Byerley Turk (1680), was shared among Arabians, Turkomans, and Akhal Tekes, which opens a discussion about the historic connections between Oriental horse types. Furthermore, we genetically traced Arabian sire line breeding in the Western World over the past 200 years. This confirmed a strong selection for relatively few male lineages and uncovered incongruences to written pedigree records. Overall, we demonstrate how fine-scaled Y-analysis contributes to a better understanding of the historical development of horse breeds.


Assuntos
Variação Genética , Cromossomo Y , Animais , Feminino , Haplótipos , Cavalos/genética , Masculino , Linhagem , Filogenia , Cromossomo Y/genética
16.
Elife ; 112022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989337

RESUMO

Y chromosomes across diverse species convergently evolve a gene-poor, heterochromatic organization enriched for duplicated genes, LTR retrotransposons, and satellite DNA. Sexual antagonism and a loss of recombination play major roles in the degeneration of young Y chromosomes. However, the processes shaping the evolution of mature, already degenerated Y chromosomes are less well-understood. Because Y chromosomes evolve rapidly, comparisons between closely related species are particularly useful. We generated de novo long-read assemblies complemented with cytological validation to reveal Y chromosome organization in three closely related species of the Drosophila simulans complex, which diverged only 250,000 years ago and share >98% sequence identity. We find these Y chromosomes are divergent in their organization and repetitive DNA composition and discover new Y-linked gene families whose evolution is driven by both positive selection and gene conversion. These Y chromosomes are also enriched for large deletions, suggesting that the repair of double-strand breaks on Y chromosomes may be biased toward microhomology-mediated end joining over canonical non-homologous end-joining. We propose that this repair mechanism contributes to the convergent evolution of Y chromosome organization across organisms.


Assuntos
Cromossomos de Insetos/genética , Drosophila/genética , Evolução Molecular , Seleção Genética , Cromossomo Y/genética , Animais , Drosophila melanogaster/genética , Drosophila simulans/genética , Especificidade da Espécie
17.
Genetics ; 220(3)2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35100374

RESUMO

Duplicates of amh are crucial for fish sex determination and differentiation. In Nile tilapia, unlike in other teleosts, amh is located on X chromosome. The Y chromosome amh (amhΔ-y) is mutated with 5 bp insertion and 233 bp deletion in the coding sequence, and tandem duplicate of amh on Y chromosome (amhy) has been identified as the sex determiner. However, the expression of amh, amhΔ-y, and amhy, their roles in germ cell proliferation and the molecular mechanism of how amhy determines sex is still unclear. In this study, expression and functions of each duplicate were analyzed. Sex reversal occurred only when amhy was mutated as revealed by single, double, and triple mutation of the 3 duplicates in XY fish. Homozygous mutation of amhy in YY fish also resulted in sex reversal. Earlier and higher expression of amhy/Amhy was observed in XY gonads compared with amh/Amh during sex determination. Amhy could inhibit the transcription of cyp19a1a through Amhr2/Smads signaling. Loss of cyp19a1a rescued the sex reversal phenotype in XY fish with amhy mutation. Interestingly, mutation of both amh and amhy in XY fish or homozygous mutation of amhy in YY fish resulted in infertile females with significantly increased germ cell proliferation. Taken together, these results indicated that up-regulation of amhy during the critical period of sex determination makes it the sex-determining gene, and it functions through repressing cyp19a1a expression via Amhr2/Smads signaling pathway. Amh retained its function in controlling germ cell proliferation as reported in other teleosts, while amhΔ-y was nonfunctionalized.


Assuntos
Hormônio Antimülleriano , Ciclídeos , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Proliferação de Células/genética , Ciclídeos/genética , Feminino , Gônadas/metabolismo , Diferenciação Sexual/genética , Cromossomo Y
18.
Mol Ecol ; 31(6): 1853-1863, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35060220

RESUMO

Differences in allele frequencies at autosomal genes between males and females in a population can result from two scenarios. First, unresolved sexual conflict over survival can produce allelic differentiation between the sexes. However, given the substantial mortality costs required to produce allelic differences between males and females at each generation, it remains unclear how many loci within the genome experience significant sexual conflict over survival. Alternatively, recent studies have shown that similarity between autosomal and Y sequences can create perceived allelic differences between the sexes. However, Y duplications are most likely in species with large nonrecombining regions, in part because they simply represent larger targets for duplications. We assessed the genomes of 120 wild-caught guppies, which experience extensive predation- and pathogen-induced mortality and have a relatively small ancestral Y chromosome. We identified seven autosomal genes that show allelic differences between male and female adults. Five of these genes show clear evidence of whole or partial gene duplication between the Y chromosome and the autosomes. The remaining two genes show evidence of partial homology to the Y. Overall, our findings suggest that the guppy genome experiences a very low level of unresolved sexual conflict over survival, and instead the Y chromosome, despite its small ancestral size and recent origin, may nonetheless accumulate genes with male-specific functions.


Assuntos
Poecilia , Animais , Feminino , Duplicação Gênica , Genoma , Masculino , Poecilia/genética , Comportamento Predatório , Cromossomo Y/genética
19.
Exp Anim ; 71(1): 82-89, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-34544911

RESUMO

In mammals, sexual fate is determined by the chromosomes of the male and female gametes during fertilization. Males (XY) or females (XX) are produced when a sperm containing a Y or X-chromosome respectively fertilizes an X-chromosome-containing unfertilized egg. However, sexing of preimplantation stage embryos cannot be conducted visually. To address this, transgenic male mouse models with the ubiquitously expressed green fluorescent protein (GFP) transgene on X- (X-GFP) or Y-chromosomes (Y-GFP) have been established. However, when crossed with wild-type females, sexing of the preimplantation stage embryos by observing the GFP signal is problematic in some cases due to X-inactivation, loss of Y-chromosome (LOY), or loss of transgene fluorescence. In this study, a mouse model with the ubiquitously expressed red fluorescent protein (RFP) transgene on the Y-chromosome was generated since RFP is easily distinguishable from GFP signals. Unfortunately, the ubiquitously expressed tdTomato RFP transgene on the Y-chromosome (Y-RFP) mouse showed the lethal phenotype after birth. No lethal phenotypes were observed when the mitochondrial locating signal N-terminal of tdTomato (mtRFP) was included in the transgene construct. Almost half of the collected fertilized eggs from Y-mtRFP male mice crossed with wild-type females had an RFP signal at the preimplantation stage (E1.5). Therefore, XY eggs were recognized as RFP-positive embryos at the preimplantation stage. Furthermore, 100% sexing was observed at the preimplantation stage using the X-linked GFP/Y-linked RFP male mouse. The established Y-mtRFP mouse models may be used to study sex chromosome related research.


Assuntos
Cromossomo X , Cromossomo Y , Animais , Feminino , Proteínas Luminescentes , Masculino , Camundongos , Camundongos Transgênicos , Cromossomo X/genética , Cromossomo Y/genética
20.
Res Vet Sci ; 144: 181-189, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34823871

RESUMO

The identification of differential proteins between X- and Y-sperm may be useful for immunological sexing of sperm. Hence, the present study was aimed to compare the protein profile of X- and Y-sorted Sahiwal bull semen using SDS-PAGE and Liquid Chromatography coupled with Mass Spectrometry (Nano LC-MS). Semen sample (n = 6) were categorized into three groups i.e., group I (X-sorted), group II (Y-sorted) and control group (both X- and Y- sperms). SDS PAGE revealed specific proteins of molecular weight between 18 and 24 kDa and between 30 and 37 kDa were present in X-sorted sperms. Also, band corresponding to 25 kDa was specific to Y-sorted sperms. Data obtained from Nano LC/MS is analysed by search engine database i.e., MASCOT and SEQUEST HT. Total, 241 proteins were identified, out of which 113 were differentially expressed between X- and Y-sorted sperms, in which 54 proteins showed at least two unique peptides. Out of 54 proteins, 27 were upregulated in X-sorted sample, 3 were upregulated in Y-sorted sample and 24 were differentially downregulated. Highly upregulated protein in X-sperm viz. Armadillo repeat containing 12 protein, NDC1 transmembrane nucleoporin, ß-nerve growth factor, C-type natriuretic peptide, Nucleobindin-2, Phosphoglycerate mutase 2, Calmodulin along with one uncharacterised protein having accession number F1MN9 may have potential to be used as biomarker for separating X and Y sperm.


Assuntos
Cromossomo X , Cromossomo Y , Animais , Bovinos , Masculino , Proteômica , Sêmen , Espermatozoides/fisiologia
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