Conserved Role of nanos Proteins in Germ Cell Development

TLDR

Nanos proteins are essential for germ cell migration and specification, with Drosophila Nanos guiding primordial germ cells into the gonad and mouse nanos genes showing differential expression in primordial germ cells. The study aims to clone and functionally analyze nanos2 and nanos3 in mice. The authors cloned nanos2 and nanos3 and performed functional analyses in mouse germ cells to assess their roles. nanos2 is expressed in male germ cells and its loss eliminates spermatogonia, whereas nanos3 is required for migrating PGCs and its loss removes germ cells in both sexes, demonstrating a conserved function of nanos proteins across invertebrates and vertebrates.

Abstract

In Drosophila , maternally supplied Nanos functions in the migration of primordial germ cells (PGCs) into the gonad; in mice, zygotic genes are involved instead. We report the cloning and the functional analyses of nanos2 and nanos3 in mice. These genes are differentially expressed in mouse PGCs. nanos2 is predominantly expressed in male germ cells, and the elimination of this gene results in a complete loss of spermatogonia. However, nanos3 is found in migrating PGCs, and the elimination of this factor results in the complete loss of germ cells in both sexes. Hence, although mice and flies differ in their mechanisms for germ cell specification, there seems to be conserved function for nanos proteins among invertebrates and vertebrates.