Integration of anthracnose resistance loci and RLK and NBS‐LRR‐encoding genes in the Phaseolus vulgaris L. genome

Abstract

AbstractThe most effective strategy to manage bean anthracnose (ANT), caused by Colletotrichum lindemuthianum, is the use of resistant cultivars. There are more than 20 ANT resistance genes that have been identified and mapped in common bean (Phaseolus vulgaris L.) chromosomes. Moreover, quantitative resistance loci (QRLs) have been described through genome‐wide association studies (GWAS). Identification of pathogen‐responsive genes and proteins on a molecular level provides a better understanding of metabolic pathways involved in ANT resistance. In this study, we investigated typical resistance proteins located close to ANT resistance loci in the common bean reference genome. Among them, we checked for proteins with nucleotide‐binding and leucine‐rich repeat (NBS‐LRR) domains and kinase domains since most resistance genes encode proteins with these domains. In addition, proteins with kinase domains are known to operate as pattern‐recognition receptors that recognize pathogen‐associated molecular patterns (PAMPs) and activate an immune response. Based on the common bean reference genome (Version 2.1), the regions 500‐kb upstream and downstream of the physical position of each ANT resistance locus were considered for a candidate gene search. Thus, an integrated map of ANT resistance loci and candidate genes (encoding defense response‐related proteins) was constructed. This map contains candidate genes for all ANT resistance genes and QRLs previously described in the literature. A total of 256 NBS‐LRR proteins and 200 protein kinases were detected. The functions of the identified candidate genes in ANT response should be validated and studies should be performed to understand how they interact with metabolic pathways.