Extensive natural epigenetic variation at a de novo originated gene

PLoS Genet. 2013 Apr;9(4):e1003437. doi: 10.1371/journal.pgen.1003437. Epub 2013 Apr 11.

Abstract

Epigenetic variation, such as heritable changes of DNA methylation, can affect gene expression and thus phenotypes, but examples of natural epimutations are few and little is known about their stability and frequency in nature. Here, we report that the gene Qua-Quine Starch (QQS) of Arabidopsis thaliana, which is involved in starch metabolism and that originated de novo recently, is subject to frequent epigenetic variation in nature. Specifically, we show that expression of this gene varies considerably among natural accessions as well as within populations directly sampled from the wild, and we demonstrate that this variation correlates negatively with the DNA methylation level of repeated sequences located within the 5'end of the gene. Furthermore, we provide extensive evidence that DNA methylation and expression variants can be inherited for several generations and are not linked to DNA sequence changes. Taken together, these observations provide a first indication that de novo originated genes might be particularly prone to epigenetic variation in their initial stages of formation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5' Untranslated Regions
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Arabidopsis* / genetics
  • Arabidopsis* / metabolism
  • Base Sequence
  • DNA Methylation / genetics*
  • Epigenesis, Genetic*
  • Gene Expression Regulation, Plant*
  • Genetic Variation
  • Phenotype
  • Starch / metabolism

Substances

  • 5' Untranslated Regions
  • Arabidopsis Proteins
  • Starch

Grants and funding

This work was supported by grants from Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP - BIOEN Program) to MV, CNRS/FAPESP to VC and MV, and the European Union Network of Excellence Epigenesys to VC. ABS was supported by a PhD studentship from FAPESP, and CT and SC by PhD studentships from the French Ministry of Research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.