2012 Fiscal Year Final Research Report

Effects of phylogenetics and hybridization of Semisulcospira snailsendemictoLake Biwa on tolerance fortrematodes

Research Project

Project/Area Number	22570025
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Ecology/Environment
Research Institution	The University of Shiga Prefecture
Principal Investigator	URABE Misako 滋賀県立大学, 環境科学部, 教授 (50263421)
Co-Investigator(Kenkyū-buntansha)	AGATSUMA Takeshi 高知大学, 医学部, 教授 (40117031)
Project Period (FY)	2010 – 2012
Keywords	寄生 / 宿主特異性 / 地理的分化 / 分子系統
Research Abstract	Some species of trematodes genus Genarchopsis, which uses Semisulcospira snails as the first intermediate hosts, were analyzed phylogenetically. The result showed that a strain of Genarchopsis(G. gigi) is endemic to Lake Biwa and diverged from other clades in relatively earlier era. This suggests that G. gigi adapts to some endemic snail species in Lake Biwa, and other species including G. goppo adapts to non-endemic species. We also developed a new molecular marker (the introns of phosphogenkinase 1 gene) for the phylogenetic analysis of host snails.Two individuals of Semisulcospira habei (usually tolerant to G. goppo and susceptible to G. gigi), which were suggested as hybrids of S. decipiens (susceptible to G. goppo) by the analysis of the ITS-1, were susceptible both to G. gigi and G. goppo. Our result suggests that interspecific hybridization affects trematode susceptibilityof snails, butmore data need to be compiled to demonstrate it.

(4 results)