Insights into the Evolutionary History of the X-Linked Sex Reversal Mutation in &lt;b&gt;&lt;i&gt;Mus minutoides&lt;/i&gt;&lt;/b&gt;: Clues from Sequence Analyses of the Y-Linked &lt;b&gt;&lt;i&gt;Sry&lt;/i&gt;&lt;/b&gt; Gene

Veyrunes, Frédéric; Pérez, Julie; Paintsil, S.N.C.; Fichet‐Calvet, Elisabeth; Britton‐Davidian, Janice

doi:10.1159/000351223

Cited by 21 publications

(22 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The subgenus Nannomys has previously been used as a suitable model for studies of karyotype evolution due to very high variability of chromosomal rearrangements [11,17,90,91]. The ancestral karyotype of the pygmy mice was composed of 36 acrocentric chromosomes [17,92], but the wide spectrum of mutational mechanisms modified the chromosomal constitution.…”

Section: Discussionmentioning

confidence: 99%

“…Finally, the phylogeographic pattern described in our study for the most karyotypically variable species, M. minutoides , can help to design further sampling of chromosomal data in lineages, where the karyotypes are not yet known. The haplotype network suggests 11 main lineages that probably differentiated in small allopatric populations at the same time, which could have led to establishment and fixation of important karyotypic differences [64,90]), possibly involving presently unknown means of sex determination [91]. If such karyotype differences among genetic lineages exist, it would be also extremely interesting to study the possible contact zones among them (see Figure 1f).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Pan-African phylogeny of Mus (subgenus Nannomys) reveals one of the most successful mammal radiations in Africa

et al. 2014

View full text Add to dashboard Cite

BackgroundRodents of the genus Mus represent one of the most valuable biological models for biomedical and evolutionary research. Out of the four currently recognized subgenera, Nannomys (African pygmy mice, including the smallest rodents in the world) comprises the only original African lineage. Species of this subgenus became important models for the study of sex determination in mammals and they are also hosts of potentially dangerous pathogens. Nannomys ancestors colonized Africa from Asia at the end of Miocene and Eastern Africa should be considered as the place of their first radiation. In sharp contrast with this fact and despite the biological importance of Nannomys, the specimens from Eastern Africa were obviously under-represented in previous studies and the phylogenetic and distributional patterns were thus incomplete.ResultsWe performed comprehensive genetic analysis of 657 individuals of Nannomys collected at approximately 300 localities across the whole sub-Saharan Africa. Phylogenetic reconstructions based on mitochondrial (CYTB) and nuclear (IRBP) genes identified five species groups and three monotypic ancestral lineages. We provide evidence for important cryptic diversity and we defined and mapped the distribution of 27 molecular operational taxonomic units (MOTUs) that may correspond to presumable species. Biogeographical reconstructions based on data spanning all of Africa modified the previous evolutionary scenarios. First divergences occurred in Eastern African mountains soon after the colonization of the continent and the remnants of these old divergences still occur there, represented by long basal branches of M. (previously Muriculus) imberbis and two undescribed species from Ethiopia and Malawi. The radiation in drier lowland habitats associated with the decrease of body size is much younger, occurred mainly in a single lineage (called the minutoides group, and especially within the species M. minutoides), and was probably linked to aridification and climatic fluctuations in middle Pliocene/Pleistocene.ConclusionsWe discovered very high cryptic diversity in African pygmy mice making the genus Mus one of the richest genera of African mammals. Our taxon sampling allowed reliable phylogenetic and biogeographic reconstructions that (together with detailed distributional data of individual MOTUs) provide a solid basis for further evolutionary, ecological and epidemiological studies of this important group of rodents.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-014-0256-2) contains supplementary material, which is available to authorized users.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Pan-African phylogeny of Mus (subgenus Nannomys) reveals one of the most successful mammal radiations in Africa

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Third, M. minutoides is one of the very few species of mammals that presents an atypical sex chromosome system–it is noteworthy for a high proportion of sex-reversed XY females [10]. The existence of XY females was first detected in South African specimens and subsequently confirmed in West African populations suggesting that the mutation likely occurred at the onset of the diversification of the lineage [11]. In summary, this species has undergone a remarkable karyotypic evolution that is paralleled by a high level of genetic structure making it a useful model for studying chromosomal evolution and speciation processes in general, and in small mammals in particular.…”

Section: Introductionmentioning

confidence: 99%

A Phylogeographic Survey of the Pygmy Mouse Mus minutoides in South Africa: Taxonomic and Karyotypic Inference from Cytochrome b Sequences of Museum Specimens

et al. 2014

View full text Add to dashboard Cite

The African pygmy mice (Mus, subgenus Nannomys) are a group of small-sized rodents that occur widely throughout sub-Saharan Africa. Chromosomal diversity within this group is extensive and numerous studies have shown the karyotype to be a useful taxonomic marker. This is pertinent to Mus minutoides populations in South Africa where two different cytotypes (2n = 34, 2n = 18) and a modification of the sex determination system (due to the presence of a Y chromosome in some females) have been recorded. This chromosomal diversity is mirrored by mitochondrial DNA sequences that unambiguously discriminate among the various pygmy mouse species and, importantly, the different M. minutoides cytotypes. However, the geographic delimitation and taxonomy of pygmy mice populations in South Africa is poorly understood. To address this, tissue samples of M. minutoides were taken and analysed from specimens housed in six South African museum collections. Partial cytochrome b sequences (400 pb) were successfully amplified from 44% of the 154 samples processed. Two species were identified: M. indutus and M. minutoides. The sequences of the M. indutus samples provided two unexpected features: i) nuclear copies of the cytochrome b gene were detected in many specimens, and ii) the range of this species was found to extend considerably further south than is presently understood. The phylogenetic analysis of the M. minutoides samples revealed two well-supported clades: a Southern clade which included the two chromosomal groups previously identified in South Africa, and an Eastern clade that extended from Eastern Africa into South Africa. Congruent molecular phylogenetic and chromosomal datasets permitted the tentative chromosomal assignments of museum specimens within the different clades as well as the correction of misidentified museum specimens.

show abstract

“…Natural populations of this species are characterized by a very high proportion (up to 80%) of fully fertile XY females phenotypically indistinguishable from females of other genotypes [Veyrunes et al, 2013]. As in lemmings and Akodon , molecular and karyological analyses revealed the existence of 2 morphologically different X chromosomes: the ancestral X and a rearranged X * [Veyrunes et al, 2010].…”

mentioning

confidence: 95%

Anatomical and Molecular Analyses of XY Ovaries from the African Pygmy Mouse <b><i>Mus minutoides</i></b>

Rahmoun

Pérez

Saunders

et al. 2014

Sex Dev

View full text Add to dashboard Cite

The African pygmy mouse Mus minutoides is characterized by the presence of a high proportion of fertile XY females in natural populations. This species displays 2 morphologically different X chromosomes: the ancestral X and a shorter one designated as X*, feminizing the X*Y individuals. This strongly suggests that in the presence of an X* chromosome, the male differentiation program is not activated despite a functional Y chromosome. In this study, we compared the histology of the adult ovaries of the 3 female genotypes (XX, XX* and X*Y) and investigated the expression of some of the main genes involved in male and female differentiation. We found that X*Y gonads display a typical ovarian structure without any testicular organization. Moreover, the ovarian somatic marker FOXL2 is detected in X*Y follicle cells and exhibits the same pattern as in XX and XX* ovaries, whereas SOX9 and DMRT1 are absent at all stages of follicular differentiation. However, surprisingly, X*Y ovaries display a higher level of Sry transcripts compared to testes. Our findings confirm the complete sex reversal in X*Y individuals with no apparent sign of masculinization, providing an attractive model to unravel new gene interactions involved in the mammalian sex determination system.

show abstract

Insights into the Evolutionary History of the X-Linked Sex Reversal Mutation in <b><i>Mus minutoides</i></b>: Clues from Sequence Analyses of the Y-Linked <b><i>Sry</i></b> Gene

Cited by 21 publications

References 36 publications

Pan-African phylogeny of Mus (subgenus Nannomys) reveals one of the most successful mammal radiations in Africa

Pan-African phylogeny of Mus (subgenus Nannomys) reveals one of the most successful mammal radiations in Africa

A Phylogeographic Survey of the Pygmy Mouse Mus minutoides in South Africa: Taxonomic and Karyotypic Inference from Cytochrome b Sequences of Museum Specimens

Anatomical and Molecular Analyses of XY Ovaries from the African Pygmy Mouse <b><i>Mus minutoides</i></b>

Contact Info

Product

Resources

About