Nodal/activin signaling promotes male germ cell fate and suppresses female programming in somatic cells.

ABSTRACT: Testicular development in the mouse is triggered in somatic cells by the function of Sry followed by the activation of fibroblast growth factor 9 (FGF9), which regulates testicular differentiation in both somatic and germ cells. However, the mechanism is unknown. We show here that the nodal/activin signaling pathway is activated in both male germ cells and somatic cells. Disruption of nodal/activin signaling drives male germ cells into meiosis and causes ectopic initiation of female-specific genes in somatic cells. Furthermore, we prove that nodal/activin-A works directly on male germ cells to induce the male-specific gene Nanos2 independently of FGF9. We conclude that nodal/activin signaling is required for testicular development and propose a model in which nodal/activin-A acts downstream of fibroblast growth factor signaling to promote male germ cell fate and protect somatic cells from initiating female differentiation.

SUBMITTER: Wu Q 

PROVIDER: S-EPMC3597207 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature