h-89 and genistin

A role for sperm-specific proteins during the early embryonic development has been suggested by a number of recent studies. However, little is known about the participation of transcription factors in that stage. Here, we show that the signal transducer and activator of transcription 1 (Stat1), but not Stat4, was phosphorylated in response to capacitation and the acrosomal reaction (AR). Moreover, Stat1 phosphorylation correlated with changes in its localization: during capacitation, Stat1 moved from the cytoplasm to the theca/flagellum fraction. During AR, Stat1 phosphorylation increased again. In addition, blocking protein kinase A (PKA) and PKC during capacitation abolished both phosphorylation and migration of Stat1. Our results show tight spatio-temporal rearrangements of Stat1, suggesting that after fertilization Stat1 participates in the first rounds of transcription within the male pronucleus.

Topics: Acrosome Reaction; Animals; Biological Transport; Blotting, Western; Calcium; Cells, Cultured; Cyclic AMP-Dependent Protein Kinases; Cytoplasm; Egtazic Acid; Electrophoresis, Polyacrylamide Gel; Genistein; Guinea Pigs; Indoles; Isoflavones; Isoquinolines; Male; Maleimides; Phosphorylation; Protein Kinase C; Protein-Tyrosine Kinases; Sperm Capacitation; Sperm Tail; Spermatozoa; STAT1 Transcription Factor; STAT4 Transcription Factor; Sulfonamides; Transcriptional Activation