著者
Yasuda Shumpei P Vogel Peter Tsuchiya Kimiyuki Han Sang-Hoon Lin Liang-Kong Suzuki Hitoshi
出版者
National Research Council Canada
雑誌
Canadian Journal of Zoology (ISSN:00084301)
巻号頁・発行日
vol.83, no.11, pp.1411-1420, 2005-11
被引用文献数
29

We examined sequence variation in the mitochondrial cytochrome b gene (1140 bp, n = 73) and control region (842–851 bp, n = 74) in the Eurasian harvest mouse (Micromys minutus (Pallas, 1771)), with samples drawn from across its range, from Western Europe to Japan. Phylogeographic analyses revealed region-specific haplotype groupings combined with overall low levels of inter-regional genetic divergence. Despite the enormous intervening distance, European and East Asian samples showed a net nucleotide divergence of only 0.36%. Based on an evolutionary rate for the cytochrome b gene of 2.4%·(site·lineage·million years)–1, the initial divergence time of these populations is estimated at around 80 000 years before present. Our findings are consistent with available fossil evidence that has recorded repeated cycles of extinction and recolonization of Europe by M. minutus through the Quaternary. The molecular data further suggest that recolonization occurred from refugia in the Central to East Asian region. Japanese haplotypes of M. minutus, with the exception of those from Tsushima Is., show limited nucleotide diversity (0.15%) compared with those found on the adjacent Korean Peninsula. This finding suggests recent colonization of the Japanese Archipelago, probably around the last glacial period, followed by rapid population growth.
著者
Harada Masashi Ando Akiro Tsuchiya Kimiyuki Koyasu Kazuhiro
出版者
社団法人日本動物学会
雑誌
Zoological science (ISSN:02890003)
巻号頁・発行日
vol.18, no.3, pp.433-442, 2001-04-10
被引用文献数
4 16

Karyotypes of the greater Japanese shrew-mole, Urotrichus talpoides (Talpidae), collected from 57 localities in Japan were studied by conventional, G- and C-band staining techniques to elucidate geographical chromosomal variations, the mechanism of changes in chromosomes, and the distribution patterns of karyotypic races. Shrew-mole samples examined could be divided geographically into two slightly divergent chromosomal forms designated as the western and eastern races. These two karyotypic races had the same diploid number (34) and fundamental number (64), but they had autosomes with different makeups. A comparison of conventional karyotypes showed a distinct intraspecific variation in shape of autosomal pair no. 14 which was classified as subtelocentric in the western race and as metacentric in the eastern race. G- and C-banding analyses revealed that karyotypic variation found in no. 14 pair was involved in pericentric inversion and quantitative changes in constitutive heterochromatin. Intraspecific and geographical variation in chromosomes caused by such karyological events is rare and unique among members of the family Talpidae examined so far. Furthermore, our results demonstrated that the clear boundary between the two parapatric karyotypic races was actually located along the Kurobe-Fuji line in the central part of Honshu, but not along the Owari-Tsuruga isthmian line previously postulated by Tsuchiya (1987,1988). Zoogeographical implications of the boundary of parapatric distribution in U. talpoides are also discussed.
著者
Shinohara Akio Suzuki Hitoshi Tsuchiya Kimiyuki Zhang Ya-Ping Luo Jing Jiang Xue-Long Wang Ying-Xiang Campbell Kevin L.
出版者
社団法人日本動物学会
雑誌
Zoological science (ISSN:02890003)
巻号頁・発行日
vol.21, no.12, pp.1177-1185, 2004-12-25
被引用文献数
5 36

We sequenced the cytochrome b gene from two little-studied mammal species from the highlands of Southwest China, the long-tailed mole Scaptonyx fusicaudus and the gracile shrew-like mole Uropsilus gracilis. This data was used to examine the phylogenetic relationships among 19 talpid species within the family Talpidae (Mammalia: Eulipotyphla). Cytochrome b gene trees supported a basal placement of shrew-like moles (Uropsilus) within the Talpidae, and suggested that fossorial specializations arose twice during talpid evolution. To assess the evolutionary relationships of moles endemic to this region, we additionally sequenced the 12S rRNA gene and the nuclear recombination-activating gene-1 from eight and ten East Asian taxa, respectively. Analyses of these single and concatenated data sets suggested that East Asian shrew moles diverged prior to the evolution of fossorial Eurasian moles. However, we were unable to determine whether semi-fossorial shrew moles are monophyletic. In contrast, fossorial Eurasian genera (Talpa, Mogera and Euroscaptor) were consistently found to form a monophyletic clade, with Mogera and Euroscaptor representing sister taxa. Furthermore, this fossorial clade grouped with the semi-aquatic Desmana, although with fairly low (35-62%) bootstrap support. Mogera imaizumii was found to be more closely related to M. wogura than to M. tokudae. This implies that the ancestors of these three species entered Japan from the Asian continent in this order via a series of migration events, suggesting that the Japanese Islands have played an important role in preserving mole lineages from ancient to recent times.
著者
Tsuchiya Kimiyuki Suzuki Hitoshi Shinohara Akio HARADA Masashi WAKANA Shigeharu SAKAIZUMI Mitsuru HAN Sang-Hoon LIN Liang-Kong KRYUKOV Alexei P.
出版者
The Genetics Society of Japan
雑誌
Genes & genetic systems (ISSN:13417568)
巻号頁・発行日
vol.75, no.1, pp.17-24, 2000-02
被引用文献数
15 42

Taxonomic analysis has previously revealed that the species of moles that inhabit Japan are characterized by exceptional species richness and a high level of endemism. Here, we focused on the evolutionary history of the four Japanese mole species of the genera <i>Euroscapter</i> and <i>Mogera</i>, examining mitochondrial cytochrome <i>b</i> (cyt <i>b</i>) gene sequences and comparing them with those of continental <i>Mogera wogura</i> (Korean and Russian populations), <i>M. insularis</i> from Taiwan, and <i>Talpa europaea</i> and <i>T. altaica</i> from the western and central Eurasian continent, respectively. Our data support the idea that in a radiation center somewhere on the Eurasian continent, a parental stock evolved to modern mole-like morph and radiated several times intermittently during the course of the evolution, spreading its branches to other peripheral geographic domains at each stage of the radiation. Under this hypothesis, the four lineages of Japanese mole species, <i>E. mizura</i>, <i>M. tokudae</i>, <i>M. imaizumii</i>, and <i>M. wogura</i>, could be explained to have immigrated to Japan in this order. <i>Mogera wogura</i> and <i>M. imaizumii</i> showed substantial amounts of geographic variation and somewhat complicated distributions of the cyt <i>b</i> gene types. These intraspecific variations are likely to be associated with the expansion processes of moles in the Japanese Islands during the Pleistocene glacial ages.<br>
著者
Suzuki Hitoshi Iwasa Masahiro A. Ishii Nobuo NAGAOKA Hiroko TSUCHIYA Kimiyuki
出版者
日本哺乳類学会
雑誌
Mammal study = The Continuation of the Journal of the Mammalogical Society of Japan (ISSN:13434152)
巻号頁・発行日
vol.24, no.1, pp.43-50, 1999-06-01
被引用文献数
6 11

We examined the geographic variation of <i>Tokudaia osimensis</i> through the analysis of mitochondria1 cytochrome <i>b</i> (cyt <i>b</i>) gene sequences and the restriction fragment length polymorphism (RFLP) in the nuclear ribosomal RNA gene (rDNA), using samples collected from Tokuno-shima and Amami-oshima in the Ryukyu Islands. The two populations show intrinsic karyological variation (Tokuno-shima, 2n=45; Amami-oshima, 2n=25). Sequences of the cyt <i>b</i> gene differed considerably between the two island populations. The extent of the sequence divergence among 1,140 bp of the gene was calculated to be 0.088 using the Kimura two parameter method, and was comparable to those between related species of rodents such as within genus <i>Mus</i> or <i>Rattus</i>. The extent of the differentiation in the rDNA-RFLP was also high. Three out of 22 restriction site variants were found to be fixed in the nuclear rDNA arrays of hundreds of copies in either one of the two island populations. These intensive inter-populational differences indicate that the two island populations may have been isolated for a considerable period of evolutionary time, probably several millions of years, despite there having been several opportunities for renewed genetic contact during the Pleistocene ice ages. Our data strongly suggest that the current taxonomic status of the populations of the two islands, Amami-oshima and Tokuno-shima, which regards them conspecific, should be reviewed.
著者
鈴木 仁 HOSODA Tetsuji SAKURAI Susumu TSUCHIYA Kimiyuki MUNECHIKA Isao KORABLEV Vladimir P.
出版者
Genetics Society of Japan
雑誌
The Japanese journal of genetics (ISSN:0021504X)
巻号頁・発行日
vol.69, no.4, pp.397-406, 1994-08-25
被引用文献数
7 9

We analyzed the restriction fragment length polymorphisms in the spacer regions of ribosomal DNA (rDNA), using twelve restriction enzymes, to examine whether the Iriomote cat is related to the leopard cat (<i>Felis bengalensis</i>). A restriction map for each taxon was constructed and the major taxon-specific types of repeating unit (repetypes) were characterized on the basis of the arrangements of restriction sites. The Iriomote cat and the leopard cat share a common repetype but this repetype is different from that of the domestic cat (<i>F. catus</i>) with an estimated sequence divergence of 1.5% and from that of the ocelot (<i>F. paradalis</i>) with an estimated sequence divergence of 2.5%. These results indicate that, phylogenetically, the Iriomote cat is closely related to the leopard cat and that the ancestral population moved from the continent to Iriomote Island quite recently. The rDNA arrays of the leopard cat exhibit considerable intragenomic size-variation, which is thought to have emerged as a result of differences in numbers of repeated DNA segments, whereas the extent of such size-variation is much lower in the rDNA of the Iriomote cat. It appears that, even though migration of the Iriomote cat occurred relatively recently, the population has diverged to some extent from its continental counterpart, perhaps via fixation of preexistent intraspecific variations rather than by generation of new variations.<br>