Deciphering the Molecular Variations of Pine Wood Nematode Bursaphelenchus xylophilus with Different Virulence

PLoS One. 2016 May 25;11(5):e0156040. doi: 10.1371/journal.pone.0156040. eCollection 2016.

Abstract

Bursaphelenchus xylophilus is the causative agent of pine wilt disease which has caused huge economic losses in many countries. It has been reported that two forms of pine wood nematodes existed in its native region, i.e., with strong virulence and weak virulence. However, little is known about the molecular differences between the two forms. To better understand their molecular variations, transcriptome and genome sequences of three strongly virulent and one weakly virulent strains were analyzed. We found 238 transcripts and 84 exons which showed notable changes between the two virulent forms. Functional analyses of both differentially expressed transcripts and exons indicated that different virulence strains showed dissimilar nematode growth, reproduction, and oxidoreductase activities. In addition, we also detected a small number of exon-skipping events in B. xylophilus. Meanwhile, 117 SNPs were identified as potential genetic markers in distinguishing the two forms. Four of them were further proved to have undergone allele specific expressions and possibly interrupted the target site of evolutionary conserved B. xylophilus miR-47. These particular SNPs were experimentally verified by including eight additional strains to ensure the validity of our sequencing results. These results could help researchers to better diagnose nematode species with different virulence and facilitate the control of pine wilt disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Exons
  • Helminth Proteins* / biosynthesis
  • Helminth Proteins* / genetics
  • Nematoda* / genetics
  • Nematoda* / metabolism
  • Nematoda* / pathogenicity
  • Pinus / parasitology*
  • Plant Diseases / parasitology*
  • Polymorphism, Single Nucleotide*
  • Transcriptome
  • Virulence Factors* / biosynthesis
  • Virulence Factors* / genetics

Substances

  • Helminth Proteins
  • Virulence Factors

Grants and funding

This work was supported by the National key Technology R&D Program (2012BAD19B0703), Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and the Doctorate Fellowship Foundation of Nanjing Forestry University (2011YB019). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.