Expression of p63 in the mouse ovary

Transcription factor p63, a member of the tumor suppressor p53 family, plays an important role in epithelial development, and its expression is found in many epithelial tissues. Our previous reports have shown that p63 is expressed in primordial and testicular germ cells. In this study, we investigated the expression and distribution of p63 isoforms (TAp63alpha, TAp63beta, TAp63gamma, DeltaNp63alpha, DeltaNp63beta and DeltaNp63gamma) in the mouse ovary. Reverse transcription-polymerase chain reaction experiments with primers specific for different p63 isoforms demonstrated that transcripts encoding the transactivation domain and alpha isoforms were preferentially expressed in the ovary. Immunolocalization of p63 proteins, presumably that of full-length p63alpha isoform, was observed in the oocytes of primordial, primary and two-layered secondary follicles. However, positive staining was not detected in the oocytes of multi-layered secondary follicles and antral follicles as they continued to develop. This data suggests that p63 may be implicated in the meiosis and cell cycle control of germ cells in the mouse ovary.