TSSK5, a novel member of the testis-specific serine/threonine kinase family, phosphorylates CREB at Ser-133, and stimulates the CRE/CREB responsive pathway

Biochem Biophys Res Commun. 2005 Aug 5;333(3):742-9. doi: 10.1016/j.bbrc.2005.05.157.


Several protein kinases have been shown to be involved in spermatogenesis. Recently, a novel subfamily of serine/threonine kinases has been isolated whose expression is limited to testis. Here, we report the fifth family member, named TSSK5, which encodes a 328 amino acid protein. RT-PCR analysis showed that TSSK5 is exclusively expressed in human testis. We isolated cAMP responsive element binding protein (CREB), a TSSK5 interacting protein via yeast two-hybrid system. The in vitro kinase assay showed that TSSK5 phosphorylated CREB at Ser-133. Using a CRE reporter system, we found that TSSK5 could stimulate the CREB/CRE responsive pathway in Hek293 cells. These results suggest that this kinase may be involved in spermatogenesis through phosphorylating CREB and then stimulating the CREB/CRE responsive pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cyclic AMP Response Element-Binding Protein / chemistry
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • DNA, Complementary
  • Humans
  • Male
  • Molecular Sequence Data
  • Phosphorylation
  • Protein-Serine-Threonine Kinases / chemistry
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • Sequence Homology, Amino Acid
  • Serine / metabolism*
  • Testis / enzymology*


  • Cyclic AMP Response Element-Binding Protein
  • DNA, Complementary
  • Serine
  • Protein-Serine-Threonine Kinases
  • TSSK4 protein, human