HSP70-2 is required for desynapsis of synaptonemal complexes during meiotic prophase in juvenile and adult mouse spermatocytes

摘要: Spermatogenic cells synthesize a unique 70-kDa heat shock protein (HSP70-2) during prophase of meiosis I, and targeted disruption the Hsp70-2 gene has shown that this is required for spermatogenic cell differentiation in adult mice. HSP70-2 associated with synaptonemal complexes formed between paired homologous chromosomes meiotic prophase. The present study focuses on nearly synchronous first wave spermatogenesis 12- to 28-day old juvenile mice determine more precisely when what processes are affected by its absence. Spermatogenesis homozygous mutant (Hsp70-2[-/-]) proceeded normally until day 15 increasing numbers pachytene spermatocytes became apoptotic beyond stage began falter. Synaptonemal assembled Hsp70-2(-/-) developed through final substage. However, failed desynapse normal diplotene were not observed. Metaphase seen tissue sections from testes mice, expression mRNAs antigens characteristic late (e.g., cyclin A1) development spermatids did occur. Thus, complex desynapsis, absence severely impairs transition stages results apoptosis beginning germ