The budding yeast HRR25 gene product is a casein kinase I isoform

Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):7008-12. doi: 10.1073/pnas.89.15.7008.


The Saccharomyces cerevisiae HRR25 gene was identified as a regulator of DNA strand-break repair. HRR25 encodes a protein kinase that is closely related to bovine casein kinase I (CKI). CKI is a ubiquitous multipotential protein kinase. Rabbit polyclonal antibodies that recognize and immunoprecipitate Hrr25p have been generated and an immune complex protein kinase assay has been developed. The reaction depends upon HRR25 and shows that Hrr25p uses casein as a substrate. The identity between Hrr25p and bovine CKI suggests that Hrr25p is a yeast isoform of the CKI family and that CKIs may play a role in regulating DNA metabolism.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Casein Kinases
  • Caseins / isolation & purification
  • Caseins / metabolism
  • Cloning, Molecular
  • Escherichia coli / genetics
  • Genes, Fungal*
  • Isoenzymes / genetics*
  • Isoenzymes / isolation & purification
  • Isoenzymes / metabolism
  • Molecular Sequence Data
  • Phosphorylation
  • Phylogeny
  • Protein Kinases / genetics*
  • Protein Kinases / isolation & purification
  • Protein Kinases / metabolism
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics*
  • Sequence Homology, Nucleic Acid


  • Caseins
  • Isoenzymes
  • Recombinant Proteins
  • Protein Kinases
  • Casein Kinases