BORODIN Pavel m. Russian Academy of Sciences, Siberian Branch, Institute of Cytology and Genetics, シベリア支部・細胞学遺伝学研究所, 教授
KOYASU Kazuhiro Aichigakuin University School of Dentist Lecturer, 歯学部, 講師 (50183348)
HARADA Masashi Osaka city University School of Medicine Assistant, 医学部, 助手 (20117964)
SAWADA Isamu Faculty of Ecomomics, Nara Industrial University professor, 経済学部, 教授 (40031497)
1) We collected 124 insectivores such as Sorex araneus, Sorex caecutiens, Sorex minutus, Sorex isodon, Sorex tundrensis, Neomys fodiens, Asioscalops altaica and Sorex spp.at the field in Novosibirk, Siberia, Russia on July and Aug.1996, and compared with the Japanese shrews.
2) The common shrew, Sorex araneus is subdivided into many chromosomal races distinguished by Robertsonian rearrangements. The Novosibirsk race has combination : hn, go, ik, mp. The house musk shrew, Suncus murinus also shows Robertsonian chromosomal variations from chromosomal number 2n=30 to 40. We established the standard karyotype and each Robertsonian fusions of Suncus murinus by the high resolution banding method. Theses two species, Sorex araneus and Suncus murinus are good animal models to estimate the effects of Robertsonian heterozygosity on reproductive performance.
3) To study the phylogenic relationships between Sorex species, the nuclear ribosomal DNA spacer and mitochondrial cytochrome b nucleotide seq
uences were analyzed on Sorex shinto collected in Honshu, Japan and Sorex caecutincecollected in Siberia, Russia. In previous report, these shrews were included in one species, but our results suggested that it is reasonable for the two animals to be divided into distinct species.
4) We tried to search for animals with lack of dissacharidase activities. We found that no activities of sucrase were showed in Soricinae shrew such as Sorex araneus, Sorex caecutiens, Sorex minutus, Sorex isodon, Sorex tundrensis, Neomys fodiens collected in Russia and Sorex shinto, Sorex saevus, Sorex sadonis, Sorex unguiculatus collected in Japan, and that presence of sucrase activities were showed in Crocidurinae shrews such as Crocidura sibirica collected in Russia and Crocidura dsinezumi and Suncus murinus except Suncus murinus collected in Nagasaki and Tarama-island, Japan. Lack of sucrase activities in Suncus murinus was controlled by an autosomal single gene. Our results indicates that these animals with no activities of sucrase are potent as an animal model for human disease. Less