Zebrafish vasa RNA but not its protein is a component of the germ plasm and segregates asymmetrically before germline specification.

ABSTRACT: Work in different organisms revealed that the vasa gene product is essential for germline specification. Here, we describe the asymmetric segregation of zebrafish vasa RNA, which distinguishes germ cell precursors from somatic cells in cleavage stage embryos. At the late blastula (sphere) stage, vasa mRNA segregation changes from asymmetric to symmetric, a process that precedes primordial germ cell proliferation and perinuclear localization of Vasa protein. Analysis of hybrid fish between Danio rerio and Danio feegradei demonstrates that zygotic vasa transcription is initiated shortly after the loss of unequal vasa mRNA segregation. Blocking DNA replication indicates that the change in vasa RNA segregation is dependent on a maternal program. Asymmetric segregation is impaired in embryos mu

SUBMITTER: Knaut H 

PROVIDER: S-EPMC2174565 | biostudies-literature | 2000 May

REPOSITORIES: biostudies-literature