FoxO3a eggs on fertility and aging

The FoxO transcription factors (FoxO1a, 3a and 4) comprise a small subfamily of the Forkhead transcription factor family. An increasing number of studies has provided genetic evidence showing that Forkhead transcription factors control crucial steps in embryogenesis and are essential for the development of all germ layers and organs (for a recent review, see Ref. [1]). A recent study by Castrillon et al. [2] has now added a function for FoxO3a in the control of follicular development.