These authors contributed equally to this work.
Comparative analysis of mitochondrial genomes of Rhizophagus irregularis – syn. Glomus irregulare – reveals a polymorphism induced by variability generating elements
Article first published online: 12 SEP 2012
© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust
Volume 196, Issue 4, pages 1217–1227, December 2012
How to Cite
Formey, D., Molès, M., Haouy, A., Savelli, B., Bouchez, O., Bécard, G. and Roux, C. (2012), Comparative analysis of mitochondrial genomes of Rhizophagus irregularis – syn. Glomus irregulare – reveals a polymorphism induced by variability generating elements. New Phytologist, 196: 1217–1227. doi: 10.1111/j.1469-8137.2012.04283.x
- Issue published online: 5 NOV 2012
- Article first published online: 12 SEP 2012
- Manuscript Accepted: 16 JUL 2012
- Manuscript Received: 14 JUN 2012
- FUI project
- DNA polymerases;
- intraspecific variability;
- inverted repeats;
- mitochondrial genomes;
- Rhizophagus irregularis ;
- single-nucleotide polymorphisms (SNPs)
- Arbuscular mycorrhizal (AM) fungi are involved in one of the most widespread plant–fungus interactions. A number of studies on the population dynamics of AM fungi have used mitochondrial (mt) DNA sequences, and yet mt AM fungus genomes are poorly known. To date, four mt genomes of three species of AM fungi are available, among which are two from Rhizophagus irregularis.
- In order to study intra- and interstrain mt genome variability of R. irregularis, we sequenced and de novo assembled four additional mt genomes of this species. We used 454 pyrosequencing and Illumina technologies to directly sequence mt genomes from total genomic DNA.
- The mt genomes are unique within each strain. Interstrain divergences in genome size, as a result of highly polymorphic intergenic and intronic sequences, were observed. The polymorphism is brought about by three types of variability generating element (VGE): homing endonucleases, DNA polymerase domain-containing open reading frames and small inverted repeats. Based on VGE positioning, mt sequences and nuclear markers, two subclades of R. irregularis were characterized.
- The discovery of VGEs highlights the great intraspecific plasticity of the R. irregularis mt genome. VGEs allow the design of powerful mt markers for the typing and monitoring of R. irregularis strains in genetic and population studies.