Cell- and stage-specific high-level expression of TBP-related factor 2 (TRF2) during mouse spermatogenesis.

Mice lacking the TBP-related factor 2 (TRF2) gene, which is highly expressed in the testis, have a severe defect in spermiogenesis. Here we show that the expression of TRF2 is both cell type- and stage-specific. TRF2 expression was first detected in the late pachytene spermatocytes at stage VIII and increased throughout the subsequent stages. After meiotic divisions, the TRF2 expression declined continuously in round spermatids during progression from stage I to stage V. This observation is consistent with an essential regulatory role of TRF2 in male germ cell differentiation during spermatogenesis.