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ABSTRACT: Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from flow-sorted chromosomes of the hairy footed gerbil, Gerbillurus paeba (2n = 36). The fluorescent in situ hybridization data revealed remarkable genome conservation: these species share a high proportion of conserved chromosomes, and differences are due to 10 Robertsonian (Rb) rearrangements (3 autapomorphies, 3 synapomorphies and 4 hemiplasies/homoplasies). Our data suggest that chromosome evolution in Desmodillus occurred at a rate of ∼1.25 rearrangements per million years (Myr), and that the rate among Gerbilliscus over a time period spanning 8 Myr is also ∼1.25 rearrangements/Myr. The recently diverged Gerbillurus (G. tytonis and G. paeba) share an identical karyotype, while Gerbilliscus kempi, G. afra and G. leucogaster differ by 6 Rb rearrangements (a rate of ∼1 rearrangement/Myr). Thus, our data suggests a very slow rate of chromosomal evolution in Southern African gerbils.
Cytogenetic and Genome Research 05/2013; · 1.53 Impact Factor
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ABSTRACT: Chromosomal evolution in carnivores has been revisited extensively using cross-species chromosome painting. Painting probes derived from flow-sorted chromosomes of the domestic dog, which has one of the most rearranged karyotypes in mammals and the highest dipoid number (2n=78) in carnivores, are a powerful tool in detecting both evolutionary intra- and inter-chromosomal rearrangements. However, only a few comparative maps have been established between dog and other non-Canidae species. Here, we extended cross-species painting with dog probes to seven more species representing six carnivore families: Eurasian lynx (Lynx lynx), the stone marten (Martes foina), the small Indian civet (Viverricula indica), the Asian palm civet (Paradoxurus hermaphrodites), Javan mongoose (Hepestes javanicas), the raccoon (Procyon lotor) and the giant panda (Ailuropoda melanoleuca). The numbers and positions of intra-chromosomal rearrangements were found to differ among these carnivore species. A comparative map between human and stone marten, and a map among the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis), stone marten and human were also established to facilitate outgroup comparison and to integrate comparative maps between stone marten and other carnivores with such maps between human and other species. These comparative maps give further insight into genome evolution and karyotype phylogenetic relationships among carnivores, and will facilitate the transfer of gene mapping data from human, domestic dog and cat to other species.
Heredity 11/2011; 108(1):17-27. · 4.60 Impact Factor
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ABSTRACT: Comparative genomic data for ochotonids (pikas) are important for understanding the karyotype evolution of lagomorphs. Here, we have established the first genome-wide chromosomal homologies between human and the Forrest's pika (Ochotona forresti, 2n = 54) by cross-species chromosome painting. Integration of our map with the published comparative chromosome map between human and rabbit has enabled the establishment of an indirect homology map between Forrest's pika and domestic rabbit (Oryctolagus cuniculus, 2n = 44), representing the 2 Lagomorpha families: Leporidae and Ochotonidae. Our results demonstrate that (1) most of the proposed ancestral eutherian syntenies or syntenic associations have been retained in the O. forresti genome; (2) the HSA1/10p association, one of the 2 signature rearrangements that were proposed to support the grouping of the orders Lagomorpha and Rodentia into a monophyletic clade called Glires, is also present in the O. forresti genome; and (3) Robertsonian translocations have contributed to the karyotype differences between O. forresti and O. cuniculus.
Cytogenetic and Genome Research 01/2011; 132(1-2):41-6. · 1.53 Impact Factor
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ABSTRACT: Xenarthra, as the probable earliest offshoot of the placental tree, represents a key taxon for understanding mammalian phylogeny. To gain further insight into the chromosomal evolution and genome organization of the xenarthrans, we have established the first genome-wide comparative chromosome map between human and the 6-banded armadillo (Euphractussexcinctus, 2n = 58), a basal species on the Xenarthra branch, by reciprocal cross-species chromosome painting. In total, 22 human autosomal paints revealed 41 homologous segments in the euchromatic genome of E. sexcinctus. Our results provide further support for the notion that the 2 human homologous segmental associations, i.e. HSA 2/8 and 7a/10p, could constitute the synapomorphies that unite the xenarthrans. Moreover, we propose that the putative ancestral Xenarthra karyotype closely resemble the 2n = 54 karyotype of the E. sexcinctus, consisting of the equivalents of HSA1p, 1q, 2a, 2b, 2c/8c, 3/21, 4a, 4b/8b, 5, 6a, 6b, 7a/10p, 7b/16p, 8a, 9, 10q, 11, 12a/22a, 12b/22b, 13, 14/15, 16q/19q, 17, 18, 19p, 20, and X. In addition, we have analysed the C-banding patterns of E. sexcinctus, and cloned, FISHmapped and sequenced 7 novel repetitive DNA segments, providing further information on the complexity of genome architecture of E. sexcinctus.
Cytogenetic and Genome Research 01/2011; 132(1-2):31-40. · 1.53 Impact Factor
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ABSTRACT: Genome-wide homologies between the tsessebe (Damaliscus lunatus, 2n = 36) and Chinese muntjac (Muntiacus reevesi, 2n = 46) have been established by cross-species painting with Chinese muntjac chromosome paints. Twenty-two autosomal painting probes detected 35 orthologous segments in the tsessebe. Hybridization results confirmed that: (i) D. lunatus carries the (9;14) reciprocal translocation that has been proposed to be a derived chromosomal landmark shared by all species of the Antilopinae; (ii) the karyotype of D. lunatus can be derived almost exclusively from the bovid ancestral karyotype through 12 Robertsonian translocations involving 24 ancestral acrocentric autosomes; (iii) in addition to the Rb fusions, pericentric heterochromatic amplification has shaped the morphology of several of the D. lunatus chromosomes. Integrated analysis of these and published cytogenetic data on pecorans has allowed us to accurately discern the karyotype history of Damaliscus (D. lunatus; D. pygargus, 2n = 38; D. hunteri, 2n = 44). The phylogenomic relationships of 3 species reflected by specific chromosomal rearrangements were consistent with published phylogenies based on morphology, suggesting that chromosomal rearrangements have played an important role in speciation within the Alcelaphini, and that karyotype characters are valuable phylogenetic markers in this group.
Cytogenetic and Genome Research 01/2011; 132(4):264-70. · 1.53 Impact Factor
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ABSTRACT: Vespertilionidae is the largest chiropteran family that comprises species of different specialization and wide geographic distribution. Up to now, only a few vespertilionid species have been studied by molecular cytogenetic approaches. Here, we have investigated the karyotypic relationships of 4 Vespertilionidae species from Siberia by G-banding and comparative chromosome painting. Painting probes from Aselliscus stoliczkanus were used to establish interspecific homologous chromosomal segments in Myotis dasycneme (2n = 44), Murina hilgendorfi (2n = 44), Plecotus auritus (2n = 32), and Vespertilio murinus (2n = 38). Robertsonian translocations and a few inversions differentiated the karyotypes of the examined species. Painting of P. auritus karyotype with human probes revealed 3 previously undetected cryptic segments homologous to human chromosomes (Homo sapiens, HSA) 8, 15, and 19, respectively. As a consequence, the existence of 2 HSA 4 + 8 syntenies in the P. auritus karyotype has been proven. In addition, a pericentric inversion or centromere shift was revealed on the smallest metacentric P. auritus chromosome 16/17 using the HSA 16 probe explaining the different G-banding pattern in comparison to the homologous Myotis chromosome 16/17.
Cytogenetic and Genome Research 01/2011; 134(3):200-5. · 1.53 Impact Factor
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L Biltueva,
N Vorobieva,
P Perelman,
V Trifonov,
V Volobouev,
V Panov,
V Ilyashenko,
S Onischenko,
P O'Brien, F Yang,
M Ferguson-Smith,
A Graphodatsky
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ABSTRACT: The genus Sorex is one of the most successful genera of Eulipotyphla. Species of this genus are characterized by a striking chromosome variability including XY1Y2 sex chromosome systems and exceptional chromosomal polymorphisms within and between populations. To study chromosomal evolution of the genus in detail, we performed cross-species chromosome painting of 7 Sorex species with S. granarius and S. araneus whole-chromosome probes and found that the tundra shrew S. tundrensis has the most rearranged karyotype among these. We reconstructed robust phylogeny of the genus Sorex based on revealed conserved chromosomal segments and syntenic associations. About 16 rearrangements led to formation of 2 major Palearctic groups after their divergence from the common ancestor: the S. araneus group (10 fusions and 1 fission) and the S. minutus group (5 fusions). Further chromosomal evolution of the 12 species inside the groups, including 5 previously investigated species, was accompanied by multiple reshuffling events: 39 fusions, 20 centromere shifts and 10 fissions. The rate of chromosomal exchanges upon formation of the genus was close to the average rate for eutherians, but increased during recent (about 6-3 million years ago) speciation within Sorex. We propose that a plausible ancestral Sorex karyotype consists of 56 elements. It underwent 20 chromosome rearrangements from the boreoeutherian ancestor, with 14 chromosomes retaining the conserved state. The set of genus-specific chromosome signatures was drawn from the human (HSA)-shrew comparative map (HSA3/12/22, 8/19/3/21, 2/13, 3/18, 11/17, 12/15 and 1/12/22). The syntenic association HSA4/20, that was previously proposed as a common trait of all Eulipotyphla species, is shown here to be an apomorphic trait of S. araneus.
Cytogenetic and Genome Research 01/2011; 135(1):51-64. · 1.53 Impact Factor
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P L Perelman,
A S Graphodatsky,
J W Dragoo,
N A Serdyukova,
G Stone,
P Cavagna,
A Menotti,
W Nie,
P C M O'Brien,
J Wang,
S Burkett,
K Yuki,
M E Roelke,
S J O'Brien, F Yang,
R Stanyon
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ABSTRACT: The karyotypic relationships of skunks (Mephitidae) with other major clades of carnivores are not yet established. Here, multi-directional chromosome painting was used to reveal the karyological relationships among skunks and between Mephitidae (skunks) and Procyonidae (raccoons). Representative species from three genera of Mephitidae (Mephitis mephitis, 2n = 50; Mephitis macroura, 2n = 50; Conepatus leuconotus, 2n = 46; Spilogale gracilis, 2n = 60) and one species of Procyonidae (Procyon lotor, 2n = 38) were studied. Chromosomal homology was mapped by hybridization of five sets of whole-chromosome paints derived from stone marten (Martes foina, 2n = 38), cat, skunks (M. mephitis; M. macroura) and human. The karyotype of the raccoon is highly conserved and identical to the hypothetical ancestral musteloid karyotype, suggesting that procyonids have a particular importance for establishing the karyological evolution within the caniforms. Ten fission events and five fusion events are necessary to generate the ancestral skunk karyotype from the ancestral carnivore karyotype. Our results show that Mephitidae joins Canidae and Ursidae as the third family of carnivores that are characterized by a high rate of karyotype evolution. Shared derived chromosomal fusion of stone marten chromosomes 6 and 14 phylogenetically links the American hog-nosed skunk and eastern spotted skunk.
Chromosome Research 12/2008; 16(8):1215-31. · 3.09 Impact Factor
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ABSTRACT: Considering the giraffe (Giraffa camelopardalis, GCA, 2n = 30) as a primitive species, its comparative genomic data are critical for our understanding of the karyotype evolution of pecorans. Here, we have established genome-wide chromosomal homologies between giraffe, Chinese muntjac (Muntiacus reevesi, MRE, 2n = 46) and human (Homo sapiens, HSA, 2n = 46) with whole sets of chromosome-specific paints from Chinese muntjac and human, in addition to providing a high-resolution G-banding karyotype of giraffe. Chinese muntjac and human chromosome paints detected 32 and 45 autosomal homologs in the genome of giraffe, respectively. Our results suggest that it would require at least thirteen fissions, six fusions and three intrachromosomal rearrangements to 'transform' the 2n = 44 eutherian ancestral karyotype to the 2n = 58 pecoran ancestral karyotype. During giraffe evolution, some ancestral eutherian syntenies (i.e. association of HSA3/21, 4/8, 7/16, 14/15, 16/19 and two forms of 12/22) have been retained, while several derived syntenies (i.e. associations of human homologous segments 2/1, 2/9, 5/19, 4/12/22, 8/9, and 10/20) have been produced. The reduction of chromosome number in giraffe from the 2n = 58 pecoran ancestral karyotype could be primarily attributed to extensive Robertsonian translocations of ancestral chromosomal segments. More complex chromosomal rearrangements (including tandem fusion, centromere repositioning and pericentric inversion) have happened during the evolution of GCA2 and GCA8.
Cytogenetic and Genome Research 02/2008; 122(2):132-8. · 1.53 Impact Factor
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ABSTRACT: We have analysed the chromosomes of three wild and endangered canid species: the maned wolf (Chrysocyon brachyurus), the bat-eared fox (Otocyon megalotis) and the fennec fox (Fennecuszerda) using classical and molecular cytogenetic methods. For the first time detailed and encompassing descriptions of the chromosomes are presented including the chromosomal assignment of nucleolar organizer regions and the 5S rRNA gene cluster. We propose a karyotype nomenclature with ideograms including more than 300 bands per haploid set for each of these three species which will form the basis for further research. In addition, we propose four basic different patterns of karyotype organization in the family Canidae. A comparison of these patterns with the most recent molecular phylogeny of Canidae revealed that the karyotype evolution of a species is not always strongly connected with its phylogenetic position. Our findings underline the need and justification for basic cytogenetic work in rare and exotic species.
Cytogenetic and Genome Research 02/2008; 121(1):25-34. · 1.53 Impact Factor
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ABSTRACT: Chinese pangolins as a representative species in the order Pholidota have highly specified morphological characters and occupy an important place in the mammalian phylogenetic tree. To obtain genomic data for this species, we have constructed a bacterial artificial chromosome (BAC) library of Chinese pangolin. The library contains 208,272 clones with an average insert size of 122.1 kb and represents approximately eight times the Chinese pangolin haploid genome (if we assume that the Chinese pangolins have a genome size similar to human). One hundred and twenty randomly-selected BAC clones were mapped onto Chinese pangolin chromosomes by fluorescence in situ hybridization (FISH), showing a largely unbiased chromosomal distribution. Several clones containing repetitive DNA and ribosomal DNA genes were also found. The BAC library and FISH mapped BAC clones are useful resources for comparative genomics and cytogenetics of mammals and in particular, the ongoing genome sequencing project of Chinese pangolins.
Cytogenetic and Genome Research 02/2008; 122(1):55-60. · 1.53 Impact Factor
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ABSTRACT: Despite marked improvements in the interpretation of systematic relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea, Sirenia and Proboscidea), remain ambiguous. The combination of a rapid radiation, a deep divergence and an extensive morphological diversification has resulted in a limited phylogenetic signal confounding resolution within this clade both at the morphological and nucleotide levels. Cross-species chromosome painting was used to delineate regions of homology between Loxodonta africana (2n=56), Procavia capensis (2n=54), Trichechus manatus latirostris (2n=48) and an outgroup taxon, the aardvark (Orycteropus afer, 2n=20). Changes specific to each lineage were identified and although the presence of a minimum of 11 synapomorphies confirmed the monophyly of Paenungulata, no change characterizing intrapaenungulate relationships was evident. The reconstruction of an ancestral paenungulate karyotype and the estimation of rates of chromosomal evolution indicate a reduced rate of genomic repatterning following the paenungulate radiation. In comparison to data available for other mammalian taxa, the paenungulate rate of chromosomal evolution is slow to moderate. As a consequence, the absence of a chromosomal character uniting two paenungulates (at the level of resolution characterized in this study) may be due to a reduced rate of chromosomal change relative to the length of time separating successive divergence events.
Proceedings of the Royal Society B: Biological Sciences 06/2007; 274(1615):1333-40. · 5.41 Impact Factor
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ABSTRACT: Karyotype descriptions are given for Scotophilus dinganii (2n = 36, FNa = 50) and a recently discovered sister-species, Scotophilus sp. nov. (2n = 36, FNa = 52). These two sibling species occur sympatrically and are distinguished by body size, echolocation frequency and cytochrome b sequence. Cytogenetically, both species differ from other Scotophilus species in the subtelocentric morphology of chromosome 2 and a terminal heterochromatic segment on the X chromosome. Further, Scotophilus sp. nov. is characterized by a subtelocentric chromosome 4 not found in any other Scotophilus species. Comparing the Scotophilus karyotype with that of the vespertilionid genus Myotis, extensive conservation of whole chromosome arms has been found recently. However, out of 25 chromosomal arms six could not be identified in Scotophilus. Therefore, in the present study fluorescence in situ hybridization with whole chromosome painting probes from Myotis myotis was carried out on metaphase preparations from Scotophilus dinganii and Scotophilus sp. nov. These experiments revealed that three previously unidentified Scotophilus chromosomes (A, B, C) contain homologous sequences to Myotis chromosomes 18 plus 22, 19 plus 25, and 16/17, respectively.
Cytogenetic and Genome Research 02/2007; 118(1):72-7. · 1.53 Impact Factor
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ABSTRACT: Tenrecs (Tenrecidae) are a widely diversified assemblage of small eutherian mammals that occur in Madagascar and Western and Central Africa. With the exception of a few early karyotypic descriptions based on conventional staining, nothing is known about the chromosomal evolution of this family. We present a detailed analysis of G-banded and molecularly defined chromosomes based on fluorescence in situ hybridization (FISH) that allows a comprehensive comparison between the karyotypes of 11 species of two closely related Malagasy genera, Microgale (10 species) and Oryzorictes (one species), of the subfamily Oryzorictinae. The karyotypes of Microgale taiva and M. parvula (2n = 32) were found to be identical to that of O. hova (2n = 32) most likely reflecting the ancestral karyotypes of both genera, as well as that of the Oryzorictinae. Parsimony analysis of chromosomal rearrangements that could have arisen following Whole Arm Reciprocal Translocations (WARTs) showed, however, that these are more likely to be the result of Robertsonian translocations. A single most parsimonious tree was obtained that provides strong support for three species associations within Microgale, all of which are consistent with previous molecular and morphological investigations. By expanding on a recently published molecular clock for the Tenrecidae we were able to place our findings in a temporal framework that shows strong chromosomal rate heterogeneity within the Oryzorictinae. We use these data to critically examine the possible role of chromosomal rearrangements in speciation within Microgale.
Chromosome Research 02/2007; 15(8):1075-91. · 3.09 Impact Factor
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ABSTRACT: B chromosomes are often considered to be one of the most mysterious elements of karyotypes (Camacho, 2004). It is generally believed that mammalian B chromosomes do not contain any protein coding genes. The discovery of a conserved KIT gene in Canidae B chromosomes has changed this view. Here we performed analysis of sequences surrounding KIT in B chromosomes of the fox and raccoon dog. The presence of the RPL23A pseudogene was shown in canid B chromosomes. The 3' end fragment of the KDR gene was found in raccoon dog B chromosomes. The size of the B-specific fragment homologous to the autosome fragment was estimated to be a minimum of 480 kbp in both species. The origin and evolution of B chromosomes in Canidae are discussed.
Cytogenetic and Genome Research 02/2007; 116(1-2):100-3. · 1.53 Impact Factor
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ABSTRACT: Golden moles (Chrysochloridae) are poorly known subterranean mammals endemic to Southern Africa that are part of the superordinal
clade Afrotheria. Using G-banding and chromosome painting we provide a comprehensive comparison of the karyotypes of five
species representing five of the nine recognized genera: Amblysomus hottentotus, Chrysochloris asiatica, Chrysospalax trevelyani, Cryptochloris zyli and Eremitalpa granti. The species are karyotypically highly conserved. In total, only four changes were detected among them. Eremitalpa granti has the most derived karyotype with 2n = 26 and differs from the remaining species (all of whom have 2n = 30) by one centric
and one telomere:telomere fusion. In addition, two intrachromosomal rearrangements were detected in A. hottentotus. The painting probes also suggest the presence of a unique satellite DNA family located on chromosomes 11 and 12 of both
C. asiatica and C. zyli. This represents a synapomorphy linking these two sympatric species as sister taxa. A molecular clock was calibrated adopting
a relaxed Bayesian approach for multigene data sets comprising publicly available sequences derived from five gene fragments
representative of three golden moles and 39 other eutherian species. The data suggest that golden moles diverged from a common
ancestor approximately 28.5mya (95% credibility interval = 21.5–36.5mya). Based on an inferred chrysochlorid ancestral karyotype
of 2n = 30, the estimated rate of 0.7 rearrangements per 10my (95% Credibility Interval = 0.54–0.93) differs from the ‘default
rate’ of mammalian chromosomal evolution which has been estimated at one change per 10 million years, thus placing the Chrysochloridae
among the slower-evolving chromosomal lineages thus far recorded.
Chromosome Research 11/2006; 14(8):793-803. · 3.09 Impact Factor
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ABSTRACT: The muntjacs (Muntiacus, Cervidae) are famous for their rapid and radical karyotypic diversification via repeated tandem chromosome fusions, constituting a paradigm for the studies of karyotypic evolution. Of the five muntjac species with defined karyotypes, three species (i.e. Muntiacus reevesi, 2n = 46; M. m. vaginalis, 2n = 6/7; and M. crinifrons, 2n = 8/9) have so far been investigated by a combined approach of comparative chromosome banding, chromosome painting and BAC mapping. The results demonstrated that extensive centromere-telomere fusions and a few centric fusions are the chromosomal mechanisms underlying the karyotypic evolution of muntjacs. Here we have applied the same approach to two additional muntjac species with less well-characterized karyotypes, M. feae (2n = 14 male ) and M. gongshanensis (2n = 8 female). High-resolution G-banded karyotypes for M. feae and M. gongshanensis are provided. The integrated analysis of hybridization results led to the establishment of a high-resolution comparative map between M. reevesi, M. feae, and M. gongshanensis, proving that all tandem fusions underpinning the karyotypic evolution of these two muntjac species are also centromere-telomere fusions. Furthermore, the results have improved our understanding of the karyotypic relationships of extant muntjac species and provided compelling cytogenetic evidence that supports the view that M. crinifrons, M. feae, and M. gongshanensis should each be treated as a distinct species.
Chromosome Research 02/2006; 14(6):637-47. · 3.09 Impact Factor
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ABSTRACT: Cross-species chromosome painting has made a great contribution to our understanding of the evolution of karyotypes and genome organizations of mammals. Several recent papers of comparative painting between tree and flying squirrels have shed some light on the evolution of the family Sciuridae and the order Rodentia. In the present study we have extended the comparative painting to the Himalayan marmot (Marmotahimalayana) and the African ground squirrel (Xerus cf. erythropus), i.e. representative species from another important squirrel group--the ground squirrels--, and have established genome-wide comparative chromosome maps between human, eastern gray squirrel, and these two ground squirrels. The results show that 1) the squirrels so far studied all have conserved karyotypes that resemble the ancestral karyotype of the order Rodentia; 2) the African ground squirrels could have retained the ancestral karyotype of the family Sciuridae. Furthermore, we have mapped the evolutionary rearrangements onto a molecular-based consensus phylogenetic tree of the family Sciuridae.
Cytogenetic and Genome Research 02/2006; 112(3-4):270-6. · 1.53 Impact Factor
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[show abstract]
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ABSTRACT: Golden moles (Chrysochloridae) are poorly known subterranean mammals endemic to Southern Africa that are part of the superordinal clade Afrotheria. Using G-banding and chromosome painting we provide a comprehensive comparison of the karyotypes of five species representing five of the nine recognized genera: Amblysomus hottentotus, Chrysochloris asiatica, Chrysospalax trevelyani, Cryptochloris zyli and Eremitalpa granti. The species are karyotypically highly conserved. In total, only four changes were detected among them. Eremitalpa granti has the most derived karyotype with 2n = 26 and differs from the remaining species (all of whom have 2n = 30) by one centric and one telomere:telomere fusion. In addition, two intrachromosomal rearrangements were detected in A. hottentotus. The painting probes also suggest the presence of a unique satellite DNA family located on chromosomes 11 and 12 of both C. asiatica and C. zyli. This represents a synapomorphy linking these two sympatric species as sister taxa. A molecular clock was calibrated adopting a relaxed Bayesian approach for multigene data sets comprising publicly available sequences derived from five gene fragments representative of three golden moles and 39 other eutherian species. The data suggest that golden moles diverged from a common ancestor approximately 28.5 mya (95% credibility interval = 21.5-36.5 mya). Based on an inferred chrysochlorid ancestral karyotype of 2n = 30, the estimated rate of 0.7 rearrangements per 10 my (95% Credibility Interval = 0.54-0.93) differs from the 'default rate' of mammalian chromosomal evolution which has been estimated at one change per 10 million years, thus placing the Chrysochloridae among the slower-evolving chromosomal lineages thus far recorded.
Chromosome Research 02/2006; 14(8):793-803. · 3.09 Impact Factor
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L Ao,
X Gu,
Q Feng,
J Wang,
P C M O'Brien,
B Fu,
X Mao,
W Su,
Y Wang,
M Volleth, F Yang,
W Nie
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ABSTRACT: The Vespertilionidae is the largest family in the order Chiroptera and has a worldwide distribution in the temperate and tropical regions. In order to further clarify the karyotype relationships at the lower taxonomic level in Vespertilionidae, genome-wide comparative maps have been constructed between Myotis myotis (MMY, 2n = 44) and six vesper bats from China: Myotis altarium (MAL, 2n = 44), Hypsugo pulveratus (HPU, 2n = 44), Nyctalus velutinus (NVE, 2n = 36), Tylonycteris robustula (TRO, 2n = 32), Tylonycteris sp. (TSP, 2n = 30)and Miniopterus fuliginosus (MFU, 2n = 46) by cross-species chromosome painting with a set of painting probes derived from flow-sorted chromosomes of Myotis myotis. Each Myotis myotis autosomal probe detected a single homologous chromosomal segment in the genomes of these six vesper bats except for MMY chromosome 3/4 paint which hybridized onto two chromosomes in the genome of M. fuliginosus. Our results show that Robertsonian translocation is the main mode of karyotype evolution in Vespertilionidae and that the addition of heterochromatic material also plays an important role in the karyotypic evolution of the genera Tylonycteris and Nyctalus. Two conserved syntenic associations (MMY9 + 23 and 18 + 19) could be the synapomorphic features for the genus Tylonycteris. The integration of our maps with the published maps has enabled us to deduce chromosomal homologies between human and these six vesper bats and provided new insight into the karyotype evolution of the family Vespertilionidae.
Cytogenetic and Genome Research 02/2006; 115(2):145-53. · 1.53 Impact Factor
