Comprehensive analysis of structural, functional, and evolutionary dynamics of Leucine Rich Repeats-RLKs in Thinopyrum elongatum.

Abstract Leucine Rich Repeats-receptor-like protein kinases (LRR-RLKs) regulate several critical biological processes ranging from growth and development to stress response. Thinopyrum elongatum harbours many desirable traits such as biotic and abiotic stress resistance and therefore commonly used by wheat breeders. In the present investigation, in-silico analysis of LRR-RLKs yielded 589 genes of which 431 were membrane surface RLKs and 158 were receptor like cytoplasmic kinases. An insight into the gene and protein structure revealed quite a conserved nature of these proteins within subgroups. A large expansion in LRR-RLKs was due to tandem and segmental duplication event. Maximum number of tandem and segmentally duplicated pairs was observed in LRR-VI and LRR-XII subfamily, respectively. Furthermore, syntenic analyses revealed that chromosome 6 harboured more (48) tandem duplicated genes while chromosome 7 possessed more (47) segmentally duplicated genes. A detailed analysis about the gene duplication events coupled with expression profiles during Fusarium graminearum infection and water deficiency unravelled the expansion of the gene family with sub functionalization and neofunctionalization. Interaction network analysis showed that LRR-RLKs can heterodimerize upon ligand binding to perform various plant functional attributes.