The unique catalytic subunit of sperm cAMP-dependent protein kinase is the product of an alternative Calpha mRNA expressed specifically in spermatogenic cells
Document Type
ArticlePublication Date
2000-09-12Keywords
*Alternative SplicingAmino Acid Sequence
Animals
Base Sequence
Brain
Catalytic Domain
Cattle
Cloning, Molecular
Consensus Sequence
Cyclic AMP-Dependent Protein KinasesHumansIsoenzymesMaleMiceMolecular Sequence DataProtein SubunitsRatsRecombinant ProteinsSequence AlignmentSequence Homology, Amino AcidSheepSpermatogenesisSpermatozoaTestisLife SciencesMedicine and Health Sciences
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cAMP-dependent protein kinase has a central role in the control of mammalian sperm capacitation and motility. Previous protein biochemical studies indicated that the only cAMP-dependent protein kinase catalytic subunit (C) in ovine sperm is an unusual isoform, termed C(s), whose amino terminus differs from those of published C isoforms of other species. Isolation and sequencing of cDNA clones encoding ovine C(s) and Calpha1 (the predominant somatic isoform) now reveal that C(s) is the product of an alternative transcript of the Calpha gene. C(s) cDNA clones from murine and human testes also were isolated and sequenced, indicating that C(s) is of ancient origin and widespread in mammals. In the mouse, C(s) transcripts were detected only in testis and not in any other tissue examined, including ciliated tissues and ovaries. Finally, immunohistochemistry of the testis shows that C(s) first appears in pachytene spermatocytes. This is the first demonstration of a cell type-specific expression for any C isoform. The conservation of C(s) throughout mammalian evolution suggests that the unique structure of C(s) is important in the subunit's localization or function within the sperm.Source
Mol Biol Cell. 2000 Sep;11(9):3031-44.Permanent Link to this Item
http://hdl.handle.net/20.500.14038/38524PubMed ID
10982398Related Resources
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