Follicle-stimulating hormone-dependent phosphorylation of vimentin in cultures of rat Sertoli cells.
Endogenous protein phosphorylation was investigated in cultured rat Sertoli cells after treatment with follicle-stimulating hormone (FSH) and pharmacological agents that activate cAMP-dependent protein kinases. In intact Sertoli cells, both phosphorylation and dephosphorylation of proteins occurred in response to treatment with these agents. Studies using cell-free preparations suggest that four phosphoproteins phosphorylated by cAMP or the catalytic subunit of cAMP-dependent protein kinase were also phosphorylated in a FSH-dependent manner in intact cells. These data suggest that FSH-dependent phosphorylation in Sertoli cells occurs through activation of a cAMP-dependent protein kinase. A FSH-dependent phosphoprotein with a molecular weight of 58,000 was identified as the intermediate filament protein vimentin, based on its migration in two-dimensional gels and its peptide map. The cellular distribution of vimentin was monitored by immunofluorescence in Sertoli cells after treatment with FSH. Results of this study support a role for intermediate filaments in FSH-dependent events in Sertoli cells.
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D003599:Cytoskeleton / Q000648:ultrastructure*; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D007381:Intermediate Filament Proteins / Q000378:metabolism*; D007526:Isoelectric Point; D008297:Male; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D051381:Rats; D012708:Sertoli Cells / Q000378:metabolism* / Q000648:ultrastructure; D014746:Vimentin
D007381:Intermediate Filament Proteins; D010750:Phosphoproteins; D014746:Vimentin; D005640:Follicle Stimulating Hormone; D000242:Cyclic AMP; D011494:Protein Kinases