title: The formation of primordial germ cells from germline cells in spherical embryos derived from the blastodisc of 2-cell embryos in goldfish, Carassius auratus.
abstract: The property of primordial germ cells (PGCs) in fragmented goldfish embryos was investigated. When 1- and 2- cell embryos were cut at several perpendicular levels at the animal-vegetal axis, cells expressing vas mRNA were observed in the resultant embryos derived from all kinds of animal fragments. Blastodisc fragments from the 1- to 2-cell stage developed to spherical embryos containing yolk body with a yolk syncytial layer (YSL). Germ ring and no tail expression were not observed in the spherical embryo. When the spherical embryo labeled with tracer dye or GFP-nos1 3'UTR mRNA was transplanted onto the animal part of the blastoderm in a host embryo at the blastula stage, PGCs of spherical embryo origin were detected around the gonadal ridges in the resultant embryos which developed normally. These results suggest that small animal fragments should contain factors sufficient for PGC differentiation and that PGCs differentiate without mesoderm induction, since mesoderm is not induced in a spherical embryo.
authors.affiliation: Laboratory of Breeding Science, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Otani
authors.forename: Tomoe
authors.initials: T
authors.lastname: Kitauchi
authors.forename: Taiju
authors.initials: T
authors.lastname: Saito
authors.forename: Suzu
authors.initials: S
authors.lastname: Sakao
authors.forename: Shingo
authors.initials: S
authors.lastname: Maegawa
authors.forename: Kunio
authors.initials: K
authors.lastname: Inoue
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Arai
authors.forename: Etsuro
authors.initials: E
authors.lastname: Yamaha
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002465:Cell Movement; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000196:embryology; D005854:Germ Cells / Q000166:cytology*; D006054:Goldfish / Q000196:embryology*; D008648:Mesoderm / Q000166:cytology