Figure 1. Generation of mutant mice with oocyte-specific deletion of Pten.

A schematic representation of deletion of Pten exon 5 in oocytes of primary and further developed follicles by using the Zp3 promoter-mediated Cre transgenic mice. The developmental stages at which the Gdf-9 promoter and the Zp3 promoter become active are indicated above the illustration of follicles in the figure.