Analysis of lectin receptor-like kinases and their functions in higher plants

Lectin receptor-like kinase (LecRLK) is considered the second largest class of very influential cell surface receptor proteins referred to as receptor-like kinases (RLKs). The LecRLK consists of a lectin and serine/threonine kinase domain at its amino-terminus and carboxyl-terminus, respectively. In addition to these domains, LecRLK is endowed with a transmembrane domain. The LecRLKs were further grouped as L-LecRLKs, G-LecRLKs, and C-LecRLKs, attributable to the binding relevancy of the lectin domain. According to many research articles, the LecRLKs are present in numerous plant species such as Arabidopsis thaliana, Gossypium hirsutum, Oryza sativa, Pisum sativum, Populus trichocarpa, Solanum lycopersicon, Solanum tuberosum, Triticum aestivum, Setaria italica L., etc. Various expression studies and cis-regulatory element analysis suggested the association of LecRLKs with several plant developmental processes, hormone responses, and stress-related signaling cascades. The Gene ontology studies pointed towards the connection of LecRLKs with molecular, biological, and cellular processes of plants. Moreover, overexpression and knockout development unveil the functioning of LecRLKs in stress resistance to both abiotic and biotic concerns. In this current chapter, we have emphasized the number and types of LecRLKs in both monocotyledonous and dicotyledonous plants and summarized their functions in plant development and stress resistance.