Lysin motif (LysM) receptor kinase required as a cell surface receptor for chitin elicitor (chitooligosaccharides) signaling leading to innate immunity in response to biotic stresses. Involved in the resistance to pathogenic fungi, probably by sensing microbe-associated molecular patterns (MAMP) and pathogen-associated molecular patterns (PAMP) (PubMed:21070404, PubMed:22891159, PubMed:24964058). Involved in the detection of microbial peptidoglycans (PGNs) and mediates PGN response (PubMed:24964058). Plays dual roles in PGN and chitin signaling during innate immunity. Acts as an adapter for LYP4 and LYP6 and mediates signal transduction from the extracellular to intracellular spaces. Participates in the activation of defense genes during response to PGN and chitin (PubMed:25335639). Phosphorylates the downstream partner RLCK185 in response to chitin elicitation (PubMed:23498959). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Homooligomer. Interacts with CEBIP (PubMed:21070404). Interacts with LYP4 and LYP6 (PubMed:24964058, PubMed:25335639). Interacts with RLCK176 (PubMed:25335639). Expressed in seedlings, roots, shoots and stems, and, to a lower extent, in flowers. Autophosphorylated; induced by chitin and derivatives. Suppression of the defense responses induced by chitin oligosaccharides. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. Truncated N-terminus. Truncated N-terminus.