Comparative analysis of mitochondrial genomes in distinct nuclear ploidy loach Misgurnus anguillicaudatus and its implications for polyploidy evolution

PLoS One. 2014 Mar 18;9(3):e92033. doi: 10.1371/journal.pone.0092033. eCollection 2014.

Abstract

Misgurnus anguillicaudatus has several natural ploidy types. To investigate whether nuclear polyploidy have an impact on mitochondrial DNA (mtDNA), the complete mitochondrial genomes (mitogenomes) of five distinct ploidy M. anguillicaudatus (natural diploid, triploid, tetraploid, pentaploid and hexaploid), which were collected in central China, were sequenced and analyzed. The five mitogenomes share the same gene arrangement and have similar gene size, base composition and codon usage pattern. The most variable regions of the mitogenome were the protein-coding genes, especially the ND4L (5.39% mutation rate). Most variations occurred in tetraploids. The phylogenetic tree showed that the tetraploid M. anguillicaudatus separated early from other ploidy loaches. Meanwhile, the mitogenomes from pentaploids, and hexaploids have the closest phylogenetic relations, but far from that of tetraploids, implying that pentaploids and hexaploids could not be formed from tetraploids, possibly from the diploids and triploids. The genus Misgurnus species were divided into two divergent inter-genus clades, and the five ploidy M. anguillicaudatus were monophyletic, which support the hypotheses about the mitochondrial introgression in loach species.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Composition
  • Biological Evolution
  • Chromosome Mapping
  • Codon
  • Cypriniformes / classification
  • Cypriniformes / genetics*
  • DNA, Mitochondrial / genetics*
  • Genetic Variation
  • Genome, Mitochondrial*
  • Phylogeny*
  • Ploidies

Substances

  • Codon
  • DNA, Mitochondrial

Grants and funding

This research was supported by the National Natural Science Foundation of China (Program No. 31001103 and 31372180) and the Fundamental Research Funds for the Central Universities (Program No. 2011PY137). This research is also a component of the Ph.D. Programs Foundation of the Ministry of Education of China (Program No. 20100146120012). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.