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Yoichi Matsuda - One of the best experts on this subject based on the ideXlab platform.
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Amplification of microsatellite repeat motifs is associated With the evolutionary differentiation and heterochromatinization of sex Chromosomes in Sauropsida
Chromosoma, 2016Co-Authors: Kazumi Matsubara, Arthur Georges, Denis O’meally, Bhumika Azad, Stephen D. Sarre, Jennifer A. Marshall Graves, Yoichi Matsuda, Tariq EzazAbstract:The sex Chromosomes in Sauropsida (reptiles and birds) have evolved independently many times. They shoW astonishing diversity in morphology ranging from cryptic to highly differentiated sex Chromosomes With male (XX/XY) and female heterogamety (ZZ/ZW). Comparing such diverse sex Chromosome systems thus provides unparalleled opportunities to capture evolution of morphologically differentiated sex Chromosomes in action. Here, We describe chromosomal mapping of 18 microsatellite repeat motifs in eight species of Sauropsida. More than tWo microsatellite repeat motifs Were amplified on the sex-specific Chromosome, W or Y, in five species ( Bassiana duperreyi , Aprasia parapulchella , Notechis scutatus , Chelodina longicollis , and Gallus gallus ) of Which the sex-specific Chromosomes Were heteromorphic and heterochromatic. Motifs (AAGG)n and (ATCC)n Were amplified on the W Chromosome of Pogona vitticeps and the Y Chromosome of Emydura macquarii , respectively. By contrast, no motifs Were amplified on the W Chromosome of Christinus marmoratus , Which is not much differentiated from the Z Chromosome. Taken together With previously published studies, our results suggest that the amplification of microsatellite repeats is tightly associated With the differentiation and heterochromatinization of sex-specific Chromosomes in sauropsids as Well as in other taxa. Although some motifs Were common betWeen the sex-specific Chromosomes of multiple species, no correlation Was observed betWeen this commonality and the species phylogeny. Furthermore, comparative analysis of sex Chromosome homology and chromosomal distribution of microsatellite repeats betWeen tWo closely related chelid turtles, C. longicollis and E. macquarii , identified different ancestry and differentiation history. These suggest multiple evolutions of sex Chromosomes in the Sauropsida.
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no interstitial telomeres on autosomes but remarkable amplification of telomeric repeats on the W sex Chromosome in the sand lizard lacerta agilis
Journal of Heredity, 2015Co-Authors: Kazumi Matsubara, Kornsorn Srikulnath, Yoichi Matsuda, Yoshinobu Uno, Emily J Miller, Mats OlssonAbstract:Telomeres are repeat (TTAGGG) n sequences that form terminal ends of Chromosomes and have several functions, such as protecting the coding DNA from erosion at mitosis. Due to chromosomal rearrangements through evolutionary history (e.g., inversions and fusions), telomeric sequences are also found betWeen the centromere and the terminal ends (i.e., at interstitial telomeric sites, ITSs). ITS telomere sequences have been implicated in heritable disease caused by genomic instability of ITS polymorphic variants, both With respect to copy number and sequence. In the sand lizard (Lacerta agilis), We have shoWn that telomere length is predictive of lifetime fitness in females but not males. To assess Whether this sex specific fitness effect could be traced to ITSs differences, We mapped (TTAGGG) n sequences using fluorescence in situ hybridization in fibroblast cells cultured from 4 specimens of knoWn sex. No ITSs could be found on autosomes in either sex. HoWever, females have heterogametic sex Chromosomes in sand lizards (ZW, 2n = 38) and the female W Chromosome shoWed degeneration and remarkable (TTAGGG) n amplification, Which Was absent in the Z Chromosomes. This Work Warrants further research on sex Chromosome content, in particular of the degenerate W Chromosome, and links to female fitness in sand lizards.
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Genomic structures of the kW1 loci on the Z and W Chromosomes in ratite birds: structural changes at an early stage of W Chromosome differentiation.
Cytogenetic and genome research, 2014Co-Authors: Junko Ishijima, Chizuko Nishida, Yoshinobu Uno, Yoichi MatsudaAbstract:The W Chromosome of ratite birds shoWs minimal morphological differentiation and retains homology of genetic linkage and gene order With a substantial stretch of the Z Chromosome; hoWever, the molecular structure in the differentiated region is still not Well knoWn. The kW1 sequence Was isolated from the kiWi as a W-specific DNA marker for PCR-based molecular sexing of ratite birds. In ratite W Chromosomes, this sequence commonly contains a ∼200-bp deletion. To characterize the very early event of avian sex Chromosome differentiation, We performed molecular cytogenetic analyses of kW1 and its flanking sequences in paleognathous and neognathous birds and reptiles. Female-specific repeats Were found in the kW1-flanking sequence of the cassoWary (Casuarius casuarius), and the repeats have been amplified in the pericentromeric region of the W Chromosomes of ratites, Which may have resulted from the cessation of meiotic recombination betWeen the Z and W Chromosomes at an early stage of sex Chromosome differentiation. The presence of the kW1 sequence in neognathous birds and a crocodilian species suggests that the kW1 sequence Was present in the ancestral genome of Archosauria; hoWever, it disappeared in other reptilian taxa and several lineages of neognathous birds.
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highly differentiated zW sex microChromosomes in the australian varanus species evolved through rapid amplification of repetitive sequences
PLOS ONE, 2014Co-Authors: Kazumi Matsubara, Arthur Georges, Jennifer Marshall A. Graves, Stephen D. Sarre, Yoichi Matsuda, Tariq EzazAbstract:Transitions betWeen sex determination systems have occurred in many lineages of squamates and it folloWs that novel sex Chromosomes Will also have arisen multiple times. The formation of sex Chromosomes may be reinforced by inhibition of recombination and the accumulation of repetitive DNA sequences. The karyotypes of monitor lizards are knoWn to be highly conserved yet the sex Chromosomes in this family have not been fully investigated. Here, We compare male and female karyotypes of three Australian monitor lizards, Varanus acanthurus, V. gouldii and V. rosenbergi, from tWo different clades. V. acanthurus belongs to the acanthurus clade and the other tWo belong to the gouldii clade. We applied C-banding and comparative genomic hybridization to reveal that these species have ZZ/ZW sex micro-Chromosomes in Which the W Chromosome is highly differentiated from the Z Chromosome. In combination With previous reports, all six Varanus species in Which sex Chromosomes have been identified have ZZ/ZW sex Chromosomes, spanning several clades on the varanid phylogeny, making it likely that the ZZ/ZW sex Chromosome is ancestral for this family. HoWever, repetitive sequences of these ZW Chromosome pairs differed among species. In particular, an (AAT)n microsatellite repeat motif mapped by fluorescence in situ hybridization on part of W Chromosome in V. acanthurus only, Whereas a (CGG)n motif mapped onto the W Chromosomes of V. gouldii and V. rosenbergi. Furthermore, the W Chromosome probe for V. acanthurus produced hybridization signals only on the centromeric regions of W Chromosomes of the other tWo species. These results suggest that the W Chromosome sequences Were not conserved betWeen gouldii and acanthurus clades and that these repetitive sequences have been amplified rapidly and independently on the W Chromosome of the tWo clades after their divergence.
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molecular cloning and characterization of the repetitive dna sequences that comprise the constitutive heterochromatin of the W Chromosomes of medaka fishes
Chromosome Research, 2012Co-Authors: Yusuke Takehana, Yoichi Matsuda, Kiyoshi Naruse, Yusuke Asada, Tadasu Shini, Yuji Kohara, Asao Fujiyama, Satoshi Hamaguchi, Mitsuru SakaizumiAbstract:Among the medaka fishes of the genus Oryzias, most species have homomorphic sex Chromosomes, While some species, such as Oryzias hubbsi and Oryzias javanicus, have heteromorphic ZW sex Chromosomes. In this study, a novel family of repetitive sequence Was molecularly cloned from O. hubbsi and characterized by Chromosome in situ and filter hybridization, respectively. This repetitive element, Which We designated as a BstNI family element, localized at heterochromatin regions on the W Chromosome, as Well as on tWo pairs of autosomes. Homologous sequences to this element Were found only in O. javanicus, Which is a sister species of O. hubbsi, suggesting that this repeated element originated in the common ancestor of these tWo species. HoWever, the intensity of the hybridization signals Was loWer in O. javanicus than in O. hubbsi, and the chromosomal location of this element in O. javanicus Was confined to heterochromatin regions on one pair of autosomes. Thus, We hypothesize that this repetitive element Was extensively amplified in the O. hubbsi lineage, especially on its W Chromosome, after the separation of the O. javanicus lineage. In addition, We also found the W chromosomal location of the 18S–28S ribosomal RNA genes in both O. hubbsi and O. javanicus. Our previous studies shoWed no linkage homology of the sex Chromosomes in these species, indicating that the RNA genes Were shared betWeen W Chromosomes of different origins. This situation may be explained by a translocation of the sex-determining region With the ribosomal RNA genes in either species or an independent accumulation of the RNA genes as a convergent process during W Chromosome degeneration.
Frantisek Marec - One of the best experts on this subject based on the ideXlab platform.
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Degenerated, Undifferentiated, Rearranged, Lost: High Variability of Sex Chromosomes in Geometridae (Lepidoptera) Identified by Sex Chromatin
'MDPI AG', 2021Co-Authors: Martina Hejnickova, Pavel Potocký, Martina Dalikova, Frantisek Marec, Svatava Kubickova, Toomas Tammaru, Marharyta Trehubenko, Magda ZrzavaAbstract: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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absence of W Chromosome in psychidae moths and implications for the theory of sex Chromosome evolution in lepidoptera
Genes, 2019Co-Authors: Martina Hejnickova, Petr Koutecký, Pavel Potocký, Irena Provaznikova, Anna Volenikova, Martina Dalikova, Sander Visser, Frantisek Marec, Magda ZrzavaAbstract:Moths and butterflies (Lepidoptera) are the largest group With heterogametic females. Although the ancestral sex Chromosome system is probably Z0/ZZ, most lepidopteran species have the W Chromosome. When and hoW the W Chromosome arose remains elusive. Existing hypotheses place the W origin either at the common ancestor of Ditrysia and Tischeriidae, or prefer independent origins of W Chromosomes in these tWo groups. Due to their phylogenetic position at the base of Ditrysia, bagWorms (Psychidae) play an important role in investigating the W Chromosome origin. Therefore, We examined the W Chromosome status in three Psychidae species, namely Proutia betulina, Taleporia tubulosa, and Diplodoma laichartingella, using both classical and molecular cytogenetic methods such as sex chromatin assay, comparative genomic hybridization (CGH), and male vs. female genome size comparison by floW cytometry. In females of all three species, no sex chromatin Was found, no female-specific Chromosome regions Were revealed by CGH, and a Z-Chromosome univalent Was observed in pachytene oocytes. In addition, the genome size of females Was significantly smaller than males. Overall, our study provides strong evidence for the absence of the W Chromosome in Psychidae, thus supporting the hypothesis of tWo independent W Chromosome origins in Tischeriidae and in advanced Ditrysia.
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W-enriched satellite sequence in the Indian meal moth, Plodia interpunctella (Lepidoptera, Pyralidae)
Chromosome Research, 2017Co-Authors: Martina Dalikova, Magda Zrzava, Svatava Kubickova, Frantisek MarecAbstract:The W Chromosome of most lepidopteran species represents the largest heterochromatin entity in the female genome. Although satellite DNA is a typical component of constitutive heterochromatin, there are only a feW knoWn satellite DNAs (satDNAs) located on the W Chromosome in moths and butterflies. In this study, We isolated and characterized neW satDNA (PiSAT1) from microdissected W Chromosomes of the Indian meal moth, Plodia interpunctella . Even though the PiSAT1 is mainly localized near the female-specific segment of the W Chromosome, short arrays of this satDNA also occur on autosomes and/or the Z Chromosome. Probably due to the predominant location in the non-recombining part of the genome, PiSAT1 exhibits a relatively large nucleotide variability in its monomers. HoWever, at least a part of all predicted functional motifs is located in conserved regions. Moreover, We detected polyadenylated transcripts of PiSAT1 in all developmental stages and in both sexes (female and male larvae, pupae and adults). Our results suggest a potential structural and functional role of PiSAT1 in the P. interpunctella genome, Which is consistent With accumulating evidence for the important role of satDNAs in eukaryotic genomes.
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Identification of WZ bivalents in orcein-stained preparations of pachytene oocytes of three tortricid species.
2013Co-Authors: Jindra Šíchová, Martina Dalikova, Petr Nguyen, Frantisek MarecAbstract:a – pachytene complement of Grapholita molesta; the WZ bivalent is indistinguishable. b – incomplete pachytene nucleus of Lobesia botrana; note a WZ bivalent (arroW) identified according to W-Chromosome heterochromatin. c – a WZ bivalent of L. botrana; note the deeply stained W-Chromosome thread While the Z-Chromosome thread shoWs a chromomere pattern (see arroWheads pointing to deeply stained chromatin beads). d – a part of pachytene nucleus of Eupoecilia ambiguella With a WZ bivalent (arroW) anchored by one end in the nucleolus (N); note that most of the W Chromosome is formed by a continuous thread except the end opposite to the nucleolar end, Which shoWs a chromomere pattern similar to the Z Chromosome (arroWheads). e – a part of zygotene/early pachytene nucleus of E. ambiguella With not yet paired sex Chromosomes; note W and Z univalents (arroWs) anchored by one end in the nucleolus (N); also note a deeply stained Z-end (arroWhead) inbuilt in the nucleolus. Bar = 10 µm; b–e have the same scale.
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rapid assessment of the sex of codling moth cydia pomonella linnaeus lepidoptera tortricidae eggs and larvae
Journal of Applied Entomology, 2009Co-Authors: Iva Fukova, Martina Dalikova, Lisa G Neven, N M Barcenas, Nadine A Gund, Frantisek MarecAbstract:TWo different methods Were tested to identify the sex of the early developmental stages of the codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) With a WZ/ZZ (female/male) sex Chromosome system. First, it Was shoWn that the sex of all larval stages can be easily determined by the presence or absence of sex chromatin, Which is formed by the female-specific W Chromosome in interphase nuclei. This trait can also be used to identify the sex of neWly hatched larvae but it does require care and accuracy. Secondly, a neW sexing technique Was developed based on a molecular marker of the codling moth W Chromosome. Flanking regions of an earlier described W-specific sequence (CpW2) Were isolated and sequenced and a 2.74 kb sequence (CpW2-EcoRI), specific for the W Chromosome, Was obtained. Several PCR tests Were conducted, Which confirmed that the CpW2-EcoRI sequence is a reliable marker for the sex identification in codling moth samples of different geographical origin. In addition, a fragment of a codling moth gene, period (Cpper) Was isolated and sequenced. Results of southern hybridization of the Cpper probe With female and male genomic DNA suggested that the Cpper gene is located on the Z Chromosome. Then a multiplex PCR assay Was developed, Which co-amplified the CpW2-EcoRI sequence to identify the W Chromosome and the Z-linked Cpper sequence, Which served as a positive control of accurate processing of tested samples. The multiplex PCR provides an easy and rapid identification of the sex of embryos and early larval instars of the codling moth.
Hans Ellegren - One of the best experts on this subject based on the ideXlab platform.
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old but not so degenerated sloW evolution of largely homomorphic sex Chromosomes in ratites
Molecular Biology and Evolution, 2014Co-Authors: Homa Papoli Yazdi, Hans EllegrenAbstract:Degeneration of the nonrecombining Chromosome is a common feature of sex Chromosome evolution, readily evident by the presence of a pair of largely heteromorphic Chromosomes, like in eutherian mammals and birds. HoWever, in ratites (order Palaeognathae, including, e.g., ostrich), the Z and W Chromosomes are similar in size and largely undifferentiated, despite avian sex Chromosome evolution Was initiated > 130 Ma. To better understand What may limit sex Chromosome evolution, We performed ostrich transcriptome sequencing and studied genes from the nonrecombining region of the W Chromosome. Fourteen gametologous gene pairs present on the W Chromosome and Z Chromosome Were identified, With synonymous sequence divergence of 0.027-0.177. The location of these genes on the Z Chromosome Was consistent With a sequential increase in divergence, starting 110-157 and ending 24-30 Ma. On the basis of the occurrence of Z-linked genes hemizygous in females, We estimate that about one-third of the Z Chromosome does not recombine With the W Chromosome in female meiosis. PairWise d(N)/d(S) betWeen gametologs decreased With age, suggesting strong evolutionary constraint in old gametologs. Lineage-specific d(N)/d(S) Was consistently higher in W-linked genes, in accordance With the loWer efficacy of selection expected in nonrecombining Chromosomes. A higher ratio of GC > AT:AT > GC substitutions in W-linked genes supports a role for GC-biased gene conversion in differentially driving base composition on the tWo sex Chromosomes. A male-to-female (M:F) expression ratio of close to one for recombining genes and close to tWo for Z-linked genes lacking a W copy shoW that dosage compensation is essentially absent. Some gametologous genes have retained active expression of the W copy in females (giving a M:F ratio of 1 for the gametologous gene pair), Whereas for others W expression has become severely reduced resulting in a M:F ratio of close to 2. These observations resemble the patterns of sex Chromosome evolution seen in other avian and mammalian lineages, suggesting similar underlying evolutionary processes, although the rate of sex Chromosome differentiation has been atypically loW. Lack of dosage compensation may be a factor hindering sex Chromosome evolution in this lineage.
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is the rate of insertion and deletion mutation male biased molecular evolutionary analysis of avian and primate sex Chromosome sequences
Genetics, 2003Co-Authors: Hannah Sundstrom, Matthew T Webster, Hans EllegrenAbstract:The rate of mutation for nucleotide substitution is generally higher among males than among females, likely oWing to the larger number of DNA replications in spermatogenesis than in oogenesis. For insertion and deletion (indel) mutations, data from a feW human genetic disease loci indicate that the tWo sexes may mutate at similar rates, possibly because such mutations arise in connection With meiotic crossing over. To address origin- and sex-specific rates of indel mutation We have conducted the first large-scale molecular evolutionary analysis of indels in noncoding DNA sequences from sex Chromosomes. The rates are similar on the X and Y Chromosomes of primates but about tWice as high on the avian Z Chromosome as on the W Chromosome. The fact that indels are not uncommon on the nonrecombining Y and W Chromosomes excludes meiotic crossing over as the main cause of indel mutation. On the other hand, the similar rates on X and Y indicate that the number of DNA replications (higher for Y than for X) is also not the main factor. Our observations are therefore consistent With a role of both DNA replication and recombination in the generation of short insertion and deletion mutations. A significant excess of deletion compared to insertion events is observed on the avian W Chromosome, consistent With gradual DNA loss on a nonrecombining Chromosome.
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reduced variation on the chicken z Chromosome and the role of selective sWeeps in sex Chromosome evolution
Genome Research, 2003Co-Authors: Hannah Sundstrom, Matthew T Webster, Hans EllegrenAbstract:Sex Chromosomes are useful for the study of hoW factors such as mutation, selection, recombination and effective population size affect diversity and divergence.A comparison of gametologous introns in seven different bird species revealed a complete lack of diversity on the female-specific W Chromosome. In contrast, Z had at least one segregating site in all examined species. This can be explained by the loWer mutation rate and loWer effective population size of W but also suggests that selection affects diversity levels on the non-recombining W Chromosome.In a diverse set of chicken breeds, the Z Chromosome shoWed reduced diversity compared to autosomes and significant heterogeneity in levels of variation. High variance in male reproductive success, leading to a reduced Z Chromosome effective population size, can partly explain this observation. In addition, We suggest that selective sWeeps frequently act on the Z Chromosome and are responsible for a significant part of the observed Z reduction. Differences in the mutation rate of Z and W Chromosome sequences indicate that the time spent in male germ line is important for the mutation rate, but does not exclude a specifically reduced mutation rate on the Z Chromosome. Estimates of mutation rate in autosomal, Z- and W-linked chicken and turkey sequences indicate a slight reduction in the rate on Z. HoWever, due to rate heterogeneity among introns this reduction is not significant and We cannot exclude male biased mutation as the single cause of rate variation betWeen the chromosomal classes.Analysis of indel mutation rates in avian and mammalian gametologous introns shoW frequent occurrence of indels on both W and Y, excluding meiotic recombination as the only source of this type of mutation. The different indel rate patterns in birds (Z>W) and mammals (X=Y) suggest that indels are caused by both replication and recombination.
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evolutionary genetics clonal inheritance of avian mitochondrial dna
Nature, 2001Co-Authors: Sofia Berlin, Hans EllegrenAbstract:We have taken a neW approach to test the commonly accepted, but recently questioned, principle of clonal inheritance of vertebrate mitochondrial DNA (mtDNA) by relating its inheritance to a female-specific marker of nuclear DNA. Whereas this is impossible in organisms With male heterogamy (such as mammals), We shoW here that genealogies of mtDNA and the female-specific W Chromosome of a bird species are completely concordant. Our results indicate that inheritance of mtDNA is free of detectable recombination effects over an evolutionary timescale.
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molecular evolution of the avian chd1 genes on the z and W sex Chromosomes
Genetics, 2000Co-Authors: Anna-karin Fridolfsson, Hans EllegrenAbstract:Genes shared betWeen the nonrecombining parts of the tWo types of sex Chromosomes offer a potential means to study the molecular evolution of the same gene exposed to different genomic environments. We have analyzed the molecular evolution of the coding sequence of the first pair of genes found to be shared by the avian Z (present in both sexes) and W (female-specific) sex Chromosomes, CHD1Z and CHD1W. We shoW here that these tWo genes evolve independently but are highly conserved at nucleotide as Well as amino acid levels, thus not indicating a female-specific role of the CHD1W gene. From comparisons of sequence data from three avian lineages, the frequency of nonsynonymous substitutions (Ka) Was found to be higher for CHD1W (1.55 per 100 sites) than for CHD1Z (0.81), While the opposite Was found for synonymous substitutions (Ks, 13.5 vs. 22.7). We argue that the loWer effective population size and the absence of recombination on the W Chromosome Will generally imply that nonsynonymous substitutions accumulate faster on this Chromosome than on the Z Chromosome. The same should be true for the Y Chromosome relative to the X Chromosome in XY systems. Our data are compatible With a male-biased mutation rate, manifested by the faster rate of neutral evolution (synonymous substitutions) on the Z Chromosome than on the female-specific W Chromosome.
Tariq Ezaz - One of the best experts on this subject based on the ideXlab platform.
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Amplification of microsatellite repeat motifs is associated With the evolutionary differentiation and heterochromatinization of sex Chromosomes in Sauropsida
Chromosoma, 2016Co-Authors: Kazumi Matsubara, Arthur Georges, Denis O’meally, Bhumika Azad, Stephen D. Sarre, Jennifer A. Marshall Graves, Yoichi Matsuda, Tariq EzazAbstract:The sex Chromosomes in Sauropsida (reptiles and birds) have evolved independently many times. They shoW astonishing diversity in morphology ranging from cryptic to highly differentiated sex Chromosomes With male (XX/XY) and female heterogamety (ZZ/ZW). Comparing such diverse sex Chromosome systems thus provides unparalleled opportunities to capture evolution of morphologically differentiated sex Chromosomes in action. Here, We describe chromosomal mapping of 18 microsatellite repeat motifs in eight species of Sauropsida. More than tWo microsatellite repeat motifs Were amplified on the sex-specific Chromosome, W or Y, in five species ( Bassiana duperreyi , Aprasia parapulchella , Notechis scutatus , Chelodina longicollis , and Gallus gallus ) of Which the sex-specific Chromosomes Were heteromorphic and heterochromatic. Motifs (AAGG)n and (ATCC)n Were amplified on the W Chromosome of Pogona vitticeps and the Y Chromosome of Emydura macquarii , respectively. By contrast, no motifs Were amplified on the W Chromosome of Christinus marmoratus , Which is not much differentiated from the Z Chromosome. Taken together With previously published studies, our results suggest that the amplification of microsatellite repeats is tightly associated With the differentiation and heterochromatinization of sex-specific Chromosomes in sauropsids as Well as in other taxa. Although some motifs Were common betWeen the sex-specific Chromosomes of multiple species, no correlation Was observed betWeen this commonality and the species phylogeny. Furthermore, comparative analysis of sex Chromosome homology and chromosomal distribution of microsatellite repeats betWeen tWo closely related chelid turtles, C. longicollis and E. macquarii , identified different ancestry and differentiation history. These suggest multiple evolutions of sex Chromosomes in the Sauropsida.
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highly differentiated zW sex microChromosomes in the australian varanus species evolved through rapid amplification of repetitive sequences
PLOS ONE, 2014Co-Authors: Kazumi Matsubara, Arthur Georges, Jennifer Marshall A. Graves, Stephen D. Sarre, Yoichi Matsuda, Tariq EzazAbstract:Transitions betWeen sex determination systems have occurred in many lineages of squamates and it folloWs that novel sex Chromosomes Will also have arisen multiple times. The formation of sex Chromosomes may be reinforced by inhibition of recombination and the accumulation of repetitive DNA sequences. The karyotypes of monitor lizards are knoWn to be highly conserved yet the sex Chromosomes in this family have not been fully investigated. Here, We compare male and female karyotypes of three Australian monitor lizards, Varanus acanthurus, V. gouldii and V. rosenbergi, from tWo different clades. V. acanthurus belongs to the acanthurus clade and the other tWo belong to the gouldii clade. We applied C-banding and comparative genomic hybridization to reveal that these species have ZZ/ZW sex micro-Chromosomes in Which the W Chromosome is highly differentiated from the Z Chromosome. In combination With previous reports, all six Varanus species in Which sex Chromosomes have been identified have ZZ/ZW sex Chromosomes, spanning several clades on the varanid phylogeny, making it likely that the ZZ/ZW sex Chromosome is ancestral for this family. HoWever, repetitive sequences of these ZW Chromosome pairs differed among species. In particular, an (AAT)n microsatellite repeat motif mapped by fluorescence in situ hybridization on part of W Chromosome in V. acanthurus only, Whereas a (CGG)n motif mapped onto the W Chromosomes of V. gouldii and V. rosenbergi. Furthermore, the W Chromosome probe for V. acanthurus produced hybridization signals only on the centromeric regions of W Chromosomes of the other tWo species. These results suggest that the W Chromosome sequences Were not conserved betWeen gouldii and acanthurus clades and that these repetitive sequences have been amplified rapidly and independently on the W Chromosome of the tWo clades after their divergence.
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Chromosome painting With V. acanthurus microChromosome probes.
2014Co-Authors: Kazumi Matsubara, Arthur Georges, Jennifer Marshall A. Graves, Tariq EzazAbstract:Painting With the W Chromosome probe in female V. acanthurus (a), the large microChromosome probe in female V. acanthurus (b), an autosomal microChromosome probe in male (c) and female V. acanthurus (d), and the W Chromosome probe in female V. rosenbergi (e) and V. gouldii (f). ArroWheads indicate hybridization signals. ‘W’, ‘Lm’ and ‘m’ indicate W Chromosomes in the three species (a, b, d–f), large microChromosomes in male and female V. acanthurus (a–d), and microChromosome to Which the probe has been hybridized in male and female V. acanthurus (c, d), respectively. Scale bars indicate 10 µm.
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Non-homologous sex Chromosomes of birds and snakes share repetitive sequences
Chromosome Research, 2010Co-Authors: Denis O’meally, Arthur Georges, Stephen D. Sarre, Hardip R. Patel, Rami Stiglec, Jennifer A. Marshall Graves, Tariq EzazAbstract:Snake sex Chromosomes provided Susumo Ohno With the material on Which he based his theory of hoW sex Chromosomes differentiate from autosomal pairs. Like birds, snakes have a ZZ male/ZW female sex Chromosome system, in Which the snake Z is a macroChromosome much the same size as the bird Z. HoWever, the gene content shoWs clearly that the snake and bird Z Chromosomes are completely non-homologous. The molecular aspect of W Chromosome degeneration in snakes remains largely unexplored. We used comparative genomic hybridization to identify the female-specific region of the W Chromosome in representative species of Australian snakes. Using this approach, We shoW that an increasingly complex suite of repeats accompanies the evolution of W Chromosome heteromorphy. In particular, We found that While the python Liasis fuscus exhibits no sex-specific repeats and indeed, no cytologically recognizable sex-specific region, the colubrid Stegonotus cucullatus shoWs a large domain on the short arm of the W Chromosome that consists of female-specific repeats, and the large W of Notechis scutatus is composed almost entirely of repetitive sequences, including Bkm and 18S rDNA-related elements. FISH mapping of both simple and complex probes shoWs patterns of repeat amplification concordant With the size of the female-specific region in each species examined. Mapping of intronic sequences of genes that are sex-linked in both birds ( DMRT1 ) and snakes ( CTNNB1 ) reveals massive amplification in discrete domains on the W Chromosome of the elapid N. scutatus . Using chicken W Chromosome paint, We demonstrate that repetitive sequences are shared betWeen the sex Chromosomes of birds and derived snakes. This could be explained by ancestral but as yet undetected shared synteny of bird and snake sex Chromosomes or may indicate functional homology of the repeats and suggests that degeneration is a convergent property of sex Chromosome evolution. We also establish that synteny of snake Z-linked genes has been conserved for at least 166 million years and that the snake Z consists of tWo conserved blocks derived from the same ancestral vertebrate Chromosome.
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temperature sex reversal implies sex gene dosage in a reptile
Science, 2007Co-Authors: Alexander E Quinn, Tariq Ezaz, Arthur Georges, Stephen D. Sarre, Fiorenzo Guarino, Jennifer Marshall A. GravesAbstract:Sex in reptiles is determined by genes on sex Chromosomes or by incubation temperature. Previously these tWo modes Were thought to be distinct, yet We shoW that high incubation temperatures reverse genotypic males (ZZ) to phenotypic females in a lizard With ZZ and ZW sex Chromosomes. Thus, the W Chromosome is not necessary for female differentiation. Sex determination is probably via a dosage-sensitive male-determining gene on the Z Chromosome that is inactivated by extreme temperatures. Our data invite a novel hypothesis for the evolution of temperature-dependent sex determination (TSD) and suggest that sex Chromosomes may exist in many TSD reptiles.
Kazumi Matsubara - One of the best experts on this subject based on the ideXlab platform.
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Amplification of microsatellite repeat motifs is associated With the evolutionary differentiation and heterochromatinization of sex Chromosomes in Sauropsida
Chromosoma, 2016Co-Authors: Kazumi Matsubara, Arthur Georges, Denis O’meally, Bhumika Azad, Stephen D. Sarre, Jennifer A. Marshall Graves, Yoichi Matsuda, Tariq EzazAbstract:The sex Chromosomes in Sauropsida (reptiles and birds) have evolved independently many times. They shoW astonishing diversity in morphology ranging from cryptic to highly differentiated sex Chromosomes With male (XX/XY) and female heterogamety (ZZ/ZW). Comparing such diverse sex Chromosome systems thus provides unparalleled opportunities to capture evolution of morphologically differentiated sex Chromosomes in action. Here, We describe chromosomal mapping of 18 microsatellite repeat motifs in eight species of Sauropsida. More than tWo microsatellite repeat motifs Were amplified on the sex-specific Chromosome, W or Y, in five species ( Bassiana duperreyi , Aprasia parapulchella , Notechis scutatus , Chelodina longicollis , and Gallus gallus ) of Which the sex-specific Chromosomes Were heteromorphic and heterochromatic. Motifs (AAGG)n and (ATCC)n Were amplified on the W Chromosome of Pogona vitticeps and the Y Chromosome of Emydura macquarii , respectively. By contrast, no motifs Were amplified on the W Chromosome of Christinus marmoratus , Which is not much differentiated from the Z Chromosome. Taken together With previously published studies, our results suggest that the amplification of microsatellite repeats is tightly associated With the differentiation and heterochromatinization of sex-specific Chromosomes in sauropsids as Well as in other taxa. Although some motifs Were common betWeen the sex-specific Chromosomes of multiple species, no correlation Was observed betWeen this commonality and the species phylogeny. Furthermore, comparative analysis of sex Chromosome homology and chromosomal distribution of microsatellite repeats betWeen tWo closely related chelid turtles, C. longicollis and E. macquarii , identified different ancestry and differentiation history. These suggest multiple evolutions of sex Chromosomes in the Sauropsida.
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no interstitial telomeres on autosomes but remarkable amplification of telomeric repeats on the W sex Chromosome in the sand lizard lacerta agilis
Journal of Heredity, 2015Co-Authors: Kazumi Matsubara, Kornsorn Srikulnath, Yoichi Matsuda, Yoshinobu Uno, Emily J Miller, Mats OlssonAbstract:Telomeres are repeat (TTAGGG) n sequences that form terminal ends of Chromosomes and have several functions, such as protecting the coding DNA from erosion at mitosis. Due to chromosomal rearrangements through evolutionary history (e.g., inversions and fusions), telomeric sequences are also found betWeen the centromere and the terminal ends (i.e., at interstitial telomeric sites, ITSs). ITS telomere sequences have been implicated in heritable disease caused by genomic instability of ITS polymorphic variants, both With respect to copy number and sequence. In the sand lizard (Lacerta agilis), We have shoWn that telomere length is predictive of lifetime fitness in females but not males. To assess Whether this sex specific fitness effect could be traced to ITSs differences, We mapped (TTAGGG) n sequences using fluorescence in situ hybridization in fibroblast cells cultured from 4 specimens of knoWn sex. No ITSs could be found on autosomes in either sex. HoWever, females have heterogametic sex Chromosomes in sand lizards (ZW, 2n = 38) and the female W Chromosome shoWed degeneration and remarkable (TTAGGG) n amplification, Which Was absent in the Z Chromosomes. This Work Warrants further research on sex Chromosome content, in particular of the degenerate W Chromosome, and links to female fitness in sand lizards.
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highly differentiated zW sex microChromosomes in the australian varanus species evolved through rapid amplification of repetitive sequences
PLOS ONE, 2014Co-Authors: Kazumi Matsubara, Arthur Georges, Jennifer Marshall A. Graves, Stephen D. Sarre, Yoichi Matsuda, Tariq EzazAbstract:Transitions betWeen sex determination systems have occurred in many lineages of squamates and it folloWs that novel sex Chromosomes Will also have arisen multiple times. The formation of sex Chromosomes may be reinforced by inhibition of recombination and the accumulation of repetitive DNA sequences. The karyotypes of monitor lizards are knoWn to be highly conserved yet the sex Chromosomes in this family have not been fully investigated. Here, We compare male and female karyotypes of three Australian monitor lizards, Varanus acanthurus, V. gouldii and V. rosenbergi, from tWo different clades. V. acanthurus belongs to the acanthurus clade and the other tWo belong to the gouldii clade. We applied C-banding and comparative genomic hybridization to reveal that these species have ZZ/ZW sex micro-Chromosomes in Which the W Chromosome is highly differentiated from the Z Chromosome. In combination With previous reports, all six Varanus species in Which sex Chromosomes have been identified have ZZ/ZW sex Chromosomes, spanning several clades on the varanid phylogeny, making it likely that the ZZ/ZW sex Chromosome is ancestral for this family. HoWever, repetitive sequences of these ZW Chromosome pairs differed among species. In particular, an (AAT)n microsatellite repeat motif mapped by fluorescence in situ hybridization on part of W Chromosome in V. acanthurus only, Whereas a (CGG)n motif mapped onto the W Chromosomes of V. gouldii and V. rosenbergi. Furthermore, the W Chromosome probe for V. acanthurus produced hybridization signals only on the centromeric regions of W Chromosomes of the other tWo species. These results suggest that the W Chromosome sequences Were not conserved betWeen gouldii and acanthurus clades and that these repetitive sequences have been amplified rapidly and independently on the W Chromosome of the tWo clades after their divergence.
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Chromosome painting With V. acanthurus microChromosome probes.
2014Co-Authors: Kazumi Matsubara, Arthur Georges, Jennifer Marshall A. Graves, Tariq EzazAbstract:Painting With the W Chromosome probe in female V. acanthurus (a), the large microChromosome probe in female V. acanthurus (b), an autosomal microChromosome probe in male (c) and female V. acanthurus (d), and the W Chromosome probe in female V. rosenbergi (e) and V. gouldii (f). ArroWheads indicate hybridization signals. ‘W’, ‘Lm’ and ‘m’ indicate W Chromosomes in the three species (a, b, d–f), large microChromosomes in male and female V. acanthurus (a–d), and microChromosome to Which the probe has been hybridized in male and female V. acanthurus (c, d), respectively. Scale bars indicate 10 µm.
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the zW micro sex Chromosomes of the chinese soft shelled turtle pelodiscus sinensis trionychidae testudines have the same origin as chicken Chromosome 15
Cytogenetic and Genome Research, 2009Co-Authors: Taiki Kawagoshi, Kazumi Matsubara, Yoshinobu Uno, Chizuko NishidaAbstract:The Chinese soft-shelled turtle (Pelodiscus sinensis, Trionychidae, Testudines) has ZZ/ZW-type micro-sex Chromosomes Where the 18S-28S ribosomal RNA genes (18S-28S rDNA) are located. The W Chromosome is morphologically differentiated from the Z Chromosome by partial deletion and amplification of 18S-28S rDNA and W-specific repetitive sequences. We recently found a functional gene (TOP3B) mapped on the P. sinensis Z Chromosome, Which is located on chicken (Gallus gallus, GGA) Chromosome 15. Then We cloned turtle homologues of 4 other GGA15-linked genes (GIT2, NF2, SBNO1, SF3A1) and localized them to P. sinensis Chromosomes. The 4 genes all mapped on the Z Chromosome, and 2 of them (SBNO1, SF3A1) Were also localized to the W Chromosome. Our mapping data suggest that at least one large inversion occurred betWeen GGA15 and the P. sinensis Z Chromosome, and that there are homologous regions in the distal portions of both the short and long arms betWeen the Z and W Chromosomes. W chromosomal differentiation in P. sinensis probably proceeded by the deletion of the proximal chromosomal region folloWed by 18S-28S rDNA amplification, after a paracentric inversion occurred at the breakpoints betWeen the distal region of 18S-28S rDNA and the proximal region of SBNO1 on the Z Chromosome.
