マスダ ヨシキ   Yoshiki Masuda
  益田 芳樹
   所属   川崎医療福祉大学  医療福祉学部 臨床心理学科
   職種   特任教授
論文種別 原著
言語種別 英語
査読の有無 査読あり
表題 Molecular phylogeny of the freshwater sponges in Lake Baikal.
掲載誌名 正式名:Journal of Zoological Systematics and Evolutionary Research
略  称:J. Zool. Syst. Evol. Research
ISSNコード:09475745
巻・号・頁 41(2),80-86頁
著者・共著者 Schröder Heinz C, Efremova Sofia M, Itskovich Valeria B, Masuda Yoshiki, Krasko Anatoli, Müller Isabel M, Müller Werner E. G
発行年月 2003/04
概要 In the present study, two new approaches have been made to resolve the phylogenetic relationship of Baikalian sponges; analysis of (1)nucleotide sequences from one mitochondrial gene, the cytochrome oxidase subunit I (COI) and of (2)one selected intron from the tubulin gene. Specimens from the following endemic Baikalian sponge species have been studied; Lubomirskia baicalensis, Baikalospongia intermedia, Baikalospongia recta, Baikalospongia bacillifera and Swartschewskia papyracea. They are all grouped to the family of Lubomirskiidae. Sequence compariosns were performed with the ubiquitously distributed freshwater spponges Spongilla lacustris (family Spongillidae) as well as with one marine sponge, Suberites domuncula. A sequence comparison of the mitochondrial COI gene revealed a monophyletic grouping of the endemic Baikalian sponges with S. Lacustris as the most related species to the common ancestor. The sequences of the COI gene from B. recta, B. intermedia, B. bacillifera and L. baicalensis were found to be indentical and separated from those of S. lacustris and S. papyracea. In a second approach, the exon/intron sequences framing the intron-2 of the sponge tubulin gene were chosen for the phylogenetic analysis. The intron sequences were aligned and used for construction of a phylogenetic tree. This analysis revealed again a monophyletic grouping with S. lacustris as the closest related species to the common ancestor. It is concluded that the Baikalian sponges, which have been studied here, are of monophyletic origin. Furthurmore, the data suggest that the endemic species S. papyracea is the phylogenetically oldest, extant, endemic Baikalian sponge species.