Germ cell specification in mice.

Specification of germ cell fate is vital to development and heredity. In mice, germ cell fate is induced in a subset of pluripotent epiblast cells during early gastrulation. Reflecting the function of the germ line as the transducer of genetic information, germ cell specification integrates at least three key events: repression of the somatic program, re-acquisition of potential pluripotency, and ensuing genome-wide epigenetic reprogramming. Blimp1 and Prdm14 are the two critical transcriptional regulators that orchestrate these events. The recent clarification of the mechanism by which signaling activities confer the germ cell fate to the epiblast cells underscores the feasibility of generating the mammalian germ cell lineage in vitro.