Regulation of protein kinase CK1αLS by dephosphorylation in response to hydrogen peroxide

Shahinaz Bedri, Stephanie M. Cizek, Iryna Rastarhuyeva, James R. Stone

Research output: Contribution to journalArticle

8 Citations (Scopus)


Low levels of hydrogen peroxide (H2O2) are mitogenic to mammalian cells and stimulate the hyperphosphorylation of heterogeneous nuclear ribonucleoprotein C (hnRNP-C) by protein kinase CK1α. However, the mechanisms by which CK1α is regulated have been unclear. Here it is demonstrated that low levels of H2O2 stimulate the rapid dephosphorylation of CK1αLS, a nuclear splice form of CK1α. Furthermore, it is demonstrated that either treatment of endothelial cells with H2O2, or dephosphorylation of CK1αLS in vitro enhances the association of CK1αLS with hnRNP-C. In addition, dephosphorylation of CK1αLS in vitro enhances the kinase's ability to phosphorylate hnRNP-C. While CK1α appears to be present in all metazoans, analysis of CK1α genomic sequences from several species reveals that the alternatively spliced nuclear localizing L-insert is unique to vertebrates, as is the case for hnRNP-C. These observations indicate that CK1αLS and hnRNP-C represent conserved components of a vertebrate-specific H2O2-responsive nuclear signaling pathway.

Original languageEnglish
Pages (from-to)242-249
Number of pages8
JournalArchives of Biochemistry and Biophysics
Issue number2
Publication statusPublished - 15 Oct 2007
Externally publishedYes



  • Casein kinase
  • Dephosphorylation
  • hnRNP-C
  • Hydrogen peroxide
  • Pre-mRNA processing
  • Protein kinase CK1
  • Protein kinases
  • Reactive oxygen species
  • RNA binding proteins

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology

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