Presence of a repressor protein for testis-specific H2B (TH2B) histone gene in early stages of spermatogenesis.

The rat testis-specific TH2B histone gene assumes a hypomethylated chromatin structure at all stages of spermatogenesis. However, the TH2B mRNA level is very low in pre-meiotic spermatogenic cells and rises sharply in meiotic pachytene spermatocytes. The low level of TH2B mRNA in pre-meiotic spermatogenic cells appears to be a result of transcriptional repression of the gene by a pre-meiotic cell-specific protein which binds to a site between the TATA element and the transcription initiation site of TH2B gene.