Systems Biology Approaches Reveal a Multi-stress Responsive WRKY Transcription Factor and Stress Associated Gene Co-expression Networks in Chickpea

摘要

Background: Chickpea is a nutritional rich premier pulse crop but its production encounterssetbacks due to various stresses and understanding of molecular mechanisms can be ascribed foremost importance.Objective: The investigation was carried out to identify the differentially expressed WRKY TFs in chickpeain response to herbicide stress and decipher their interacting partners.Methods: For this purpose, transcriptome wide identification of WRKY TFs in chickpea was done. Behaviorof the differentially expressed TFs was compared between other stress conditions. Orthology based cofunctionalgene networks were derived from Arabidopsis. Gene ontology and functional enrichment analysiswas performed using Blast2GO and STRING software. Gene Coexpression Network (GCN) was constructedin chickpea using publicly available transcriptome data. Expression pattern of the identified genenetwork was studied in chickpea-Fusarium interactions.Results: A unique WRKY TF (Ca_08086) was found to be significantly (q value = 0.02) upregulated notonly under herbicide stress but also in other stresses. Co-functional network of 14 genes, namelyCa_08086, Ca_19657, Ca_01317, Ca_20172, Ca_12226, Ca_15326, Ca_04218, Ca_07256, Ca_14620,Ca_12474, Ca_11595, Ca_15291, Ca_11762 and Ca_03543 were identified. GCN revealed 95 hub genesbased on the significant probability scores. Functional annotation indicated role in callose deposition andresponse to chitin. Interestingly, contrasting expression pattern of the 14 network genes was observed inwilt resistant and susceptible chickpea genotypes, infected with Fusarium.Conclusion: This is the first report of identification of a multi-stress responsive WRKY TF and its associatedGCN in chickpea.