2013 Fiscal Year Final Research Report

Analysis of early developments in a viviparous fish Xenotoca eiseni

Research Project

Project/Area Number	24657161
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
Research Field	Evolutionary biology
Research Institution	Kyoto University
Principal Investigator	IIDA Atsuo 京都大学, 再生医科学研究所, 助教 (90437278)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	胎生 / 魚類 / 繁殖
Research Abstract	I analyzed a mechanism of non-mammalian viviparous system using a live-bearer teleost Xenotoca eiseni. The viviparous fish doesn't possess defined analog of fetal organs corresponding to a placenta and an umbilical cable of mammals. They have unique ribbon-like structure elongated from a perianal. This structure is presumed to be a functional analog of the fetal organ of mammals, which plays a role for absorption of maternal nutrients. I found that the ribbon-like structure of the fetal fry is disrupted by programed cell death in perinatal stage. Such regression mechanism has not reported in mammals. It was presumed to be a unique system in viviparous fish.

(3 results)