ik3-1/Cables is a substrate for cyclin-dependent kinase 3 (cdk 3)

Eur J Biochem. 2001 Dec;268(23):6076-82. doi: 10.1046/j.0014-2956.2001.02555.x.

Abstract

p70ik3-1 (a 70-kDa protein) contains a cyclin box, and binds to p35cdk3 in vivo and in vitro [Matsuoka, M., Matsuura, Y., Semba, K. & Nishimoto, I. (2000) Biochem. Biophys. Res. Commun. 273, 442-447]. In spite of its structural similarity to cyclins, p70ik3-1 does not activate cyclin-dependent kinase 3 (cdk3)-mediated phosphorylation of pRb, histone H1, or the C-terminal domain of RNA polymerase II. Here, we report that Ser274 of p70ik3-1 is phosphorylated by cdk2 or cdk3 bound to cyclin A and to cyclin E in vitro. We also found that in COS7 cells in which cyclin E and cdk3 were ectopically overexpressed, the phosphorylation level of Ser274 in coexpressed p70ik3-1 is upregulated. We therefore conclude that p70ik3-1 is a substrate for cdk3-mediated phosphorylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Binding Sites
  • CDC2-CDC28 Kinases*
  • COS Cells
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cyclin A / genetics
  • Cyclin A / metabolism
  • Cyclin E / genetics
  • Cyclin E / metabolism
  • Cyclin-Dependent Kinase 2
  • Cyclin-Dependent Kinase 3
  • Cyclin-Dependent Kinases / genetics
  • Cyclin-Dependent Kinases / metabolism*
  • Cyclins / chemistry
  • Cyclins / genetics
  • Cyclins / metabolism*
  • DNA, Complementary / genetics
  • Humans
  • In Vitro Techniques
  • Mutagenesis, Site-Directed
  • Phosphoproteins / chemistry
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Phosphorylation
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Serine / chemistry
  • Substrate Specificity
  • Transfection

Substances

  • CABLES1 protein, human
  • Carrier Proteins
  • Cyclin A
  • Cyclin E
  • Cyclins
  • DNA, Complementary
  • Phosphoproteins
  • Recombinant Proteins
  • Serine
  • Protein-Serine-Threonine Kinases
  • CDC2-CDC28 Kinases
  • CDK2 protein, human
  • CDK3 protein, human
  • Cdk3 protein, mouse
  • Cyclin-Dependent Kinase 2
  • Cyclin-Dependent Kinase 3
  • Cyclin-Dependent Kinases