Genetic framework of cyclin-dependent kinase function in Arabidopsis

Dev Cell. 2012 May 15;22(5):1030-40. doi: 10.1016/j.devcel.2012.02.015.


Cyclin-dependent kinases (CDKs) are at the heart of eukaryotic cell-cycle control. The yeast Cdc2/CDC28 PSTAIRE kinase and its orthologs such as the mammalian Cdk1 have been found to be indispensable for cell-cycle progression in all eukaryotes investigated so far. CDKA;1 is the only PSTAIRE kinase in the flowering plant Arabidopsis and can rescue Cdc2/CDC28 mutants. Here, we show that cdka;1 null mutants are viable but display specific cell-cycle and developmental defects, e.g., in S phase entry and stem cell maintenance. We unravel that the crucial function of CDKA;1 is the control of the plant Retinoblastoma homolog RBR1 and that codepletion of RBR1 and CDKA;1 rescued most defects of cdka;1 mutants. Our work further revealed a basic cell-cycle control system relying on two plant-specific B1-type CDKs, and the triple cdk mutants displayed an early germline arrest. Taken together, our data indicate divergent functional differentiation of Cdc2-type kinases during eukaryote evolution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / embryology
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • CDC2-CDC28 Kinases / genetics
  • CDC2-CDC28 Kinases / metabolism
  • Cyclin-Dependent Kinases / genetics*
  • Cyclin-Dependent Kinases / metabolism
  • Evolution, Molecular
  • Microscopy, Electron, Scanning
  • Mitosis / physiology
  • Mutation
  • Plant Roots / embryology
  • Plant Roots / genetics
  • Plant Roots / metabolism
  • Plant Shoots / embryology
  • Plant Shoots / genetics
  • Plant Shoots / metabolism
  • S Phase / physiology*


  • Arabidopsis Proteins
  • RBR1 protein, Arabidopsis
  • CDC2-CDC28 Kinases
  • CDKA1 protein, Arabidopsis
  • CDKB1;2 protein, Arabidopsis
  • Cyclin-Dependent Kinases