Related Experiment Video
Updated: Jun 21, 2026
A Method for Characterizing Embryogenesis in Arabidopsis
Published on: August 4, 2017
The Arabidopsis MCM2 gene is essential to embryo development and its over-expression alters root meristem function
Di An Ni1, Rosangela Sozzani2, Sophie Blanchet1
1Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France.
Abstract:
* 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.
Insights
Minichromosome maintenance 2 (AtMCM2) is essential for plant development. Disruption is lethal, while over-expression impacts growth and root meristem function, revealing its role in DNA replication and meristem maintenance.
Area of Science:
- Plant Molecular Biology
- Cell Cycle Regulation
- Developmental Biology
Background:
- Minichromosome maintenance (MCM) proteins are crucial for DNA replication as components of the pre-replication complex.
- AtMCM2 is a key subunit of the MCM complex in Arabidopsis, likely functioning as a DNA helicase during S phase.
Purpose of the Study:
- To elucidate the function of AtMCM2 in Arabidopsis by employing loss- and gain-of-function strategies.
- To understand the role of AtMCM2 in plant development, DNA replication, and root meristem maintenance.
Main Methods:
- Analysis of two null alleles of AtMCM2 to assess loss-of-function phenotypes.
- Generation of transgenic Arabidopsis expressing AtMCM2 under the constitutive 35S promoter for gain-of-function studies.
- Phenotypic analysis of wild-type and plt1,2 mutant plants over-expressing AtMCM2.
Main Results:
- Complete loss of AtMCM2 function results in lethality during early embryogenesis.
- Over-expression of AtMCM2 leads to reduced plant growth, inhibited endoreduplication, and altered root cap development.
- In plt1,2 mutants, AtMCM2 over-expression induced lateral root initiation near the root tip, a novel phenotype.
Conclusions:
- AtMCM2 plays a vital role in DNA replication and is essential for Arabidopsis embryogenesis.
- AtMCM2 is implicated in the regulation of root meristem function and development.
More Related Videos
11:04Geomagnetic Field (Gmf) and Plant Evolution: Investigating the Effects of Gmf Reversal on Arabidopsis thaliana Development and Gene Expression
Published on: November 30, 2015
08:52A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana
Published on: November 9, 2013