Molecular evolutionary study on the phylogeny and body plan of chaetognath.

2005 Fiscal Year Final Research Report Summary

• Project/Area Number: 15570078
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Biodiversity/Systematics
• Research Institution: Mie University
• Principal Investigator: GOTO Taichiro Mie University, Faculty of Education, Professor, 教育学部, 教授 (90183813)
• Co-Investigator(Kenkyū-buntansha): KAGAYA Yasuaki Mie University, Center for molecular and genetics, Assistant, 生命科学支援センター, 助手 (20335152) ; SHIMOTORI Taishin Aichi Gakuin University, Division of General Education, Lecturer, 教養部, 講師 (20410574)
• Project Period (FY): 2003 – 2005
• Keywords: chaetognath / arrow worm / vasa / phylogenetic analysis

Research Abstract

Phylogenetical position of the chaetognaths are always debated. Recent molecular evidence has suggested that they are not deuterostomes but protostomes. Molecular investigations of chaetognath development are much needed to resolve evolutionary relationship. Existence of germ granules is one of the characteristic in chaetognath development. In the present study we examined the vasa-related genes which are involved in germ line in higher metazoans and would be a molecular marker to compare phylogenetic relationship. We cloned the vasa-related gene from the arrow worm Paraspadella gotoi A vasa-related gene (Pgvas1) was isolated and the whole length of Pgvas1 was obtained. The phylogenetic analysis suggested that Pgvas1 was close to a vasa-related gene from the planarian (Plvas1). The result indicates that chaetognath is a very ancient taxon in bilateralians. Pgvas1 was expressed in the PGCs, indicatings the vasa-related gene is involved in germline cells. We have also been trying to isolate homologs of dpp and sog which are involved in the formation of the dorso-ventral axis.