Global Transcriptome Profiling Identified Transcription Factors, Biological Process, and Associated Pathways for Pre-Harvest Aflatoxin Contamination in Groundnut

Abstract

Pre-harvest aflatoxin contamination (PAC) in groundnut is a serious quality concern globally, and drought stress before harvest further exacerbate its intensity, leading to the deterioration of produce quality. Understanding the host–pathogen interaction and identifying the candidate genes responsible for resistance to PAC will provide insights into the defense mechanism of the groundnut. In this context, about 971.63 million reads have been generated from 16 RNA samples under controlled and Aspergillus flavus infected conditions, from one susceptible and seven resistant genotypes. The RNA-seq analysis identified 45,336 genome-wide transcripts under control and infected conditions. This study identified 57 transcription factor (TF) families with major contributions from 6570 genes coding for bHLH (719), MYB-related (479), NAC (437), FAR1 family protein (320), and a few other families. In the host (groundnut), defense-related genes such as senescence-associated proteins, resveratrol synthase, seed linoleate, pathogenesis-related proteins, peroxidases, glutathione-S-transferases, chalcone synthase, ABA-responsive gene, and chitinases were found to be differentially expressed among resistant genotypes as compared to susceptible genotypes. This study also indicated the vital role of ABA-responsive ABR17, which co-regulates the genes of ABA responsive elements during drought stress, while providing resistance against A. flavus infection. It belongs to the PR-10 class and is also present in several plant–pathogen interactions.

Proteomic profiling of Arachis hypogaea in response to drought stress and overexpression of AhLEA2 improves drought tolerance

“…ABR17 is a member of the group 10 family of pathogenesis-related proteins (PR 10), Srivastava et al (2006) found that ABR17 from pea confers multiple stress tolerance in A. thaliana. ABR17 from peanut also regulates the genes for ABA responsive elements during drought stress, providing resistance against Aspergillus flavus infection (Soni et al 2021). As a critical plant hormone, we will further research ABA and its related genes in our future work.…”

“…ABR17 from peanut also regulates the genes for ABA responsive elements during drought stress, providing resistance against Aspergillus flavus infection (Soni et al . 2021). As a critical plant hormone, we will further research ABA and its related genes in our future work.…”

Comparative Transcriptome Analysis of Genes Involved in Sesquiterpene Alkaloid Biosynthesis in Trichoderma longibrachiatum MD33 and UN32

“…The unique transcripts were obtained after removing the low number of reads from the raw data. We annotated all unigenes against a full set of BLAST searches to find the most descriptive annotations, including the NR ( e -value = 1e-5), NT ( e -value = 1e-5), KOG ( e -value = 1e-3), PFAM ( e -value = 0.01), Swiss-Prot ( e -value = 1e-5), ITAK (TF prediction software based on hmmscan) ( Soni et al, 2021 ), Gene Ontology (GO) ( e -value = 1e-6), and Kyoto Encyclopedia of Genes and Genomes (KEGG) ( e -value = 1e-10) database. To calculate and normalize the transcript abundance of the unigenes in each sample, the FPKM method was adopted ( Li and Dewey, 2011 ).…”

Gene Co-expression Network Analysis of the Comparative Transcriptome Identifies Hub Genes Associated With Resistance to Aspergillus flavus L. in Cultivated Peanut (Arachis hypogaea L.)

“…In general, pre-and post-harvest contamination are two major types caused by A. flavus (Guo et al, 2008a(Guo et al, ,b, 2011Liao et al, 2009;Wang et al, 2013;Clevenger et al, 2016;Zhao et al, 2019;Soni et al, 2021). Two types of mechanism for host resistance to A. flavus, in vitro seed colonization and aflatoxin production, have been documented, which were further proved to be independently inherited (Liao et al, 2009;Nigam et al, 2009;Pandey et al, 2019;Soni et al, 2020), thus making it a great challenge for the researchers to elucidate resistance mechanism, breed resistant lines, and eventually control the disease in peanuts.…”