pH effect on strain-specific transcriptomes of the take-all fungus

PLoS One. 2020 Jul 30;15(7):e0236429. doi: 10.1371/journal.pone.0236429. eCollection 2020.

Abstract

The soilborne fungus Gaeumannomyces tritici (G. tritici) causes the take-all disease on wheat roots. Ambient pH has been shown to be critical in different steps of G. tritici life cycle such as survival in bulk soil, saprophytic growth, and pathogenicity on plants. There are however intra-specific variations and we previously found two types of G. tritici strains that grow preferentially either at acidic pH or at neutral/alkaline pH; gene expression involved in pH-signal transduction pathway and pathogenesis was differentially regulated in two strains representative of these types. To go deeper in the description of the genetic pathways and the understanding of this adaptative mechanism, transcriptome sequencing was achieved on two strains (PG6 and PG38) which displayed opposite growth profiles in two pH conditions (acidic and neutral). PG6, growing better at acidic pH, overexpressed in this condition genes related to cell proliferation. In contrast, PG38, which grew better at neutral pH, overexpressed in this condition genes involved in fatty acids and amino acid metabolisms, and genes potentially related to pathogenesis. This strain also expressed stress resistance mechanisms at both pH, to assert a convenient growth under various ambient pH conditions. These differences in metabolic pathway expression between strains at different pH might buffer the effect of field or soil variation in wheat fields, and explain the success of the pathogen.

MeSH terms

  • Ascomycota / genetics*
  • Ascomycota / growth & development
  • Ascomycota / isolation & purification
  • Gene Expression Profiling
  • Gene Expression Regulation, Fungal
  • Gene Ontology
  • Genes, Fungal
  • Hydrogen-Ion Concentration
  • Mycelium / growth & development
  • Species Specificity
  • Transcriptome / genetics*
  • Triticum

Grants and funding

The author(s) received no specific funding for this work.