Functional Genomic Analysis of Aspergillus Flavus Interacting With Resistant and Susceptible Peanut

Toxins (Basel). 2016 Feb 15;8(2):46. doi: 10.3390/toxins8020046.

Abstract

In the Aspergillus flavus (A. flavus)-peanut pathosystem, development and metabolism of the fungus directly influence aflatoxin contamination. To comprehensively understand the molecular mechanism of A. flavus interaction with peanut, RNA-seq was used for global transcriptome profiling of A. flavus during interaction with resistant and susceptible peanut genotypes. In total, 67.46 Gb of high-quality bases were generated for A. flavus-resistant (af_R) and -susceptible peanut (af_S) at one (T1), three (T2) and seven (T3) days post-inoculation. The uniquely mapped reads to A. flavus reference genome in the libraries of af_R and af_S at T2 and T3 were subjected to further analysis, with more than 72% of all obtained genes expressed in the eight libraries. Comparison of expression levels both af_R vs. af_S and T2 vs. T3 uncovered 1926 differentially expressed genes (DEGs). DEGs associated with mycelial growth, conidial development and aflatoxin biosynthesis were up-regulated in af_S compared with af_R, implying that A. flavus mycelia more easily penetrate and produce much more aflatoxin in susceptible than in resistant peanut. Our results serve as a foundation for understanding the molecular mechanisms of aflatoxin production differences between A. flavus-R and -S peanut, and offer new clues to manage aflatoxin contamination in crops.

Keywords: Aspergillus flavus; RNA-seq; aflatoxin biosynthesis; interaction; peanut.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arachis / microbiology*
  • Aspergillus flavus / genetics*
  • Aspergillus flavus / physiology
  • Gene Expression Regulation, Fungal*
  • Genome, Fungal
  • Genomics
  • Host-Pathogen Interactions / genetics*
  • RNA, Fungal / analysis
  • Seeds / microbiology
  • Sequence Analysis, RNA

Substances

  • RNA, Fungal