Novel complexes of cyclin-dependent kinases and a cyclin-like protein from Arabidopsis thaliana with a function unrelated to cell division

Cell Mol Life Sci. 2003 Feb;60(2):401-12. doi: 10.1007/s000180300033.


Although the majority of cyclin-dependent kinases (CDKs) play a key role in cell cycle progression, recent evidence has shown that CDKs are also implicated in transcription regulation. Here, we describe two Arabidopsis CDKs designated Arath;CDKC;1 and Arath; CDKC;2. These CDKs share a PITAIRE signature in the cyclin-binding domain and the structural characteristics of mammalian CDK9. Yeast two-hybrid screens and immunoprecipitation assays identified CDKC-interacting proteins with homology to the animal cyclin T/cyclin K group. We suggest that these Arabidopsis CDKCs may be part of a kinase complex similar to the animal positive transcription elongation factor b, whose activity is essential for transcription control. Expression studies showed that Arath; CDKC transcripts are mainly confined to epidermal tissues and are most abundant in flower tissues. No expression was detected in actively dividing Arabidopsis tissues, suggesting a role for the CDKC proteins in differentiated cells.

Publication types

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

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Arabidopsis / chemistry
  • Arabidopsis / metabolism*
  • Cell Division
  • Cyclin-Dependent Kinases / chemistry*
  • Cyclin-Dependent Kinases / metabolism*
  • Cyclins / chemistry*
  • Cyclins / metabolism*
  • Evolution, Molecular
  • Gene Expression Regulation, Plant*
  • Molecular Sequence Data
  • Protein Structure, Tertiary
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Sequence Homology, Amino Acid


  • Cyclins
  • RNA, Messenger
  • Cyclin-Dependent Kinases

Associated data

  • GENBANK/A40268
  • GENBANK/AF249734
  • GENBANK/G71404
  • GENBANK/O60563
  • GENBANK/P50750
  • GENBANK/T09572
  • GENBANK/T50815
  • RefSeq/NP_565622
  • RefSeq/NP_570930