Altered cell cycle distribution, hyperplasia, and inhibited differentiation in Arabidopsis caused by the D-type cyclin CYCD3

Plant Cell. 2003 Jan;15(1):79-92. doi: 10.1105/tpc.004838.


CYCD3;1 expression in Arabidopsis is associated with proliferating tissues such as meristems and developing leaves but not with differentiated tissues. Constitutive overexpression of CYCD3;1 increases CYCD3;1-associated kinase activity and reduces the proportion of cells in the G1-phase of the cell cycle. Moreover, CYCD3;1 overexpression leads to striking alterations in development. Leaf architecture in overexpressing plants is altered radically, with a failure to develop distinct spongy and palisade mesophyll layers. Associated with this, we observe hyperproliferation of leaf cells; in particular, the epidermis consists of large numbers of small, incompletely differentiated polygonal cells. Endoreduplication, a marker for differentiated cells that have exited from the mitotic cell cycle, is inhibited strongly in CYCD3;1-overexpressing plants. Transcript analysis reveals an activation of putative compensatory mechanisms upon CYCD3;1 overexpression or subsequent cell cycle activation. These results demonstrate that cell cycle exit in the G1-phase is required for normal cellular differentiation processes during plant development and suggest a critical role for CYCD3 in the switch from cell proliferation to the final stages of differentiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Cell Cycle / physiology*
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Cell Differentiation / physiology
  • Cell Division / physiology
  • Cyclin D3
  • Cyclin-Dependent Kinases / genetics
  • Cyclin-Dependent Kinases / metabolism*
  • Cyclins / genetics
  • Cyclins / metabolism*
  • Flowering Tops / genetics
  • Flowering Tops / physiology
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Plant
  • Meristem / genetics
  • Meristem / physiology
  • Plant Shoots / genetics
  • Plant Shoots / physiology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism


  • AINTEGUMENTA protein, Arabidopsis
  • Arabidopsis Proteins
  • Cell Cycle Proteins
  • Cyclin D3
  • Cyclins
  • Transcription Factors
  • Cyclin-Dependent Kinases