The Arabidopsis MCM2 gene is essential to embryo development and its over-expression alters root meristem function

New Phytol. 2009 Oct;184(2):311-322. doi: 10.1111/j.1469-8137.2009.02961.x. Epub 2009 Jul 24.


* Minichromosome maintenance (MCM) proteins are subunits of the pre-replication complex that probably function as DNA helicases during the S phase of the cell cycle. Here, we investigated the function of AtMCM2 in Arabidopsis. * To gain an insight into the function of AtMCM2, we combined loss- and gain-of-function approaches. To this end, we analysed two null alleles of AtMCM2, and generated transgenic plants expressing AtMCM2 downstream of the constitutive 35S promoter. * Disruption of AtMCM2 is lethal at a very early stage of embryogenesis, whereas its over-expression results in reduced growth and inhibition of endoreduplication. In addition, over-expression of AtMCM2 induces the formation of additional initials in the columella root cap. In the plt1,2 mutant, defective for root apical meristem maintenance, over-expression of AtMCM2 induces lateral root initiation close to the root tip, a phenotype not reported in the wild-type or in plt1,2 mutants, even when cell cycle regulators, such as AtCYCD3;1, were over-expressed. * Taken together, our results provide evidence for the involvement of AtMCM2 in DNA replication, and suggest that it plays a crucial role in root meristem function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / embryology
  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Cell Cycle / genetics
  • Embryonic Development / genetics*
  • Gene Expression Regulation, Plant
  • Genes, Plant*
  • Meristem / genetics*
  • Mutation
  • Phenotype
  • Plant Roots / genetics*
  • Plant Roots / growth & development
  • Plant Roots / metabolism
  • Plants, Genetically Modified
  • Promoter Regions, Genetic


  • Arabidopsis Proteins