Analysis of the Transcriptome of the Infective Stage of the Beet Cyst Nematode, H. schachtii

PLoS One. 2016 Jan 29;11(1):e0147511. doi: 10.1371/journal.pone.0147511. eCollection 2016.

Abstract

The beet cyst nematode, Heterodera schachtii, is a major root pest that significantly impacts the yield of sugar beet, brassicas and related species. There has been limited molecular characterisation of this important plant pathogen: to identify target genes for its control the transcriptome of the pre-parasitic J2 stage of H. schachtii was sequenced using Roche GS FLX. Ninety seven percent of reads (i.e., 387,668) with an average PHRED score > 22 were assembled with CAP3 and CLC Genomics Workbench into 37,345 and 47,263 contigs, respectively. The transcripts were annotated by comparing with gene and genomic sequences of other nematodes and annotated proteins on public databases. The annotated transcripts were much more similar to sequences of Heterodera glycines than to those of Globodera pallida and root knot nematodes (Meloidogyne spp.). Analysis of these transcripts showed that a subset of 2,918 transcripts was common to free-living and plant parasitic nematodes suggesting that this subset is involved in general nematode metabolism and development. A set of 148 contigs and 183 singletons encoding putative homologues of effectors previously characterised for plant parasitic nematodes were also identified: these are known to be important for parasitism of host plants during migration through tissues or feeding from cells or are thought to be involved in evasion or modulation of host defences. In addition, the presence of sequences from a nematode virus is suggested. The sequencing and annotation of this transcriptome significantly adds to the genetic data available for H. schachtii, and identifies genes primed to undertake required roles in the critical pre-parasitic and early post-parasitic J2 stages. These data provide new information for identifying potential gene targets for future protection of susceptible crops against H. schachtii.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Beta vulgaris / parasitology*
  • Brassica / parasitology*
  • Gene Ontology
  • Helminth Proteins / genetics*
  • High-Throughput Nucleotide Sequencing
  • Host-Parasite Interactions
  • Life Cycle Stages / genetics
  • Molecular Sequence Annotation
  • Molecular Sequence Data
  • Phylogeny
  • Sequence Alignment
  • Transcriptome*
  • Tylenchoidea / classification
  • Tylenchoidea / genetics*
  • Tylenchoidea / growth & development
  • Tylenchoidea / virology

Substances

  • Helminth Proteins

Grants and funding

Murdoch University provided PhD studentship for PN; RG was supported by an Australian India Strategic Research Fund Grant (BF030027); Nemgenix Pty. Ltd. contributed funds for consumables and support in the form of salaries for JFN, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of this author is articulated in the "author contributions" section.