PCNA in the testis of the frog, Rana esculenta: A molecular marker of the mitotic testicular epithelium proliferation

Proliferating cell nuclear antigen (PCNA) plays an essential role in nuclei c acid metabolism as a component of the replication and repair machinery. T his toroidal-shaped protein encircles DNA and can slide bidirectionally alo ng the duplex. One of the well-established functions for PCNA is its role a s the processing factor for DNA polymerase delta and epsilon. It has become apparent that PCNA interacts with proteins involved in the cell cycle. The PCNA interactions with different cellular proteins and the importance of t hese interactions are also discussed. To examine the different mitotic test icular epithelium proliferation during the annual discontinuous frog (Rana esculenta) spermatogenesis, the temporal and the spatial PCNA expression ar e described and give a useful endogenous molecular marker. (C) 2000 Academi c Press.