Cyclin A1 is expressed in mouse ovary.

Cyclin A1 belongs to the type-A cyclins and participates in cell cycle regulation. Since its discovery, cyclin A1 has been shown mostly in testis. It plays important roles in spermatogenesis. However, there were also reports on ovary expression of cyclin A1. Therefore, we intended to revisit the expression of cyclin A1 in mouse ovary. Our study showed that cyclin A1 was expressed at the mRNA level and the protein level in mouse ovary. Tissue staining revealed that cyclin A1 was expressed in maturating oocytes. With the recent data on the functions of cyclins in somatic and stem cells, we also discussed the possibilities of further studies of cyclin A1 in mouse oocytes and perhaps in the oogonial stem cells. Our findings not only add to the supportive evidence of cyclin A1 expression in oocytes, but also may promote more interest in exploring cyclin A1 functions in ovary.