Artificially induced tetraploid masu salmon have the ability to form primordial germ cells

概要

論文の詳細を見る
Diploid gametes generated with tetraploid animals are a stepping stone to improving techniques of chromosome manipulation. But artificially induced tetraploid individuals generally die soon after hatching. Diploid gametes could have been induced by in vivo cultures of tetraploid primordial germ cells (PGCs) through germ-line chimera. In the present study, characteristics of PGCs were studied in inviable tetraploid masu salmon, Oncorhynchus masou. Histological observation of tetraploid embryos revealed that the same or smaller numbers of PGCs were observed and they migrate into the genital ridges as did diploid PGCs during gonadogenesis. By whole mount in situ hybridization using vasa mRNA, 4-35 vasa-positive signals were detected in a pair of genital ridges of tetraploids. By cytological observation of genital ridge cell suspensions, several large round cells were observed, some of which extended pseudopodia. They also contained large nuclei and round granules in their cytoplasm, characteristics of PGCs. As the results suggest that inviable artificial tetraploids have PGCs, we expect to achieve diploid gamete production through surrogate propagation and tetraploid fish production.
2009-07-01