Abstract
Plants and animals face microbial attacks as a hazard of everyday life, and have evolved innate immunity systems to defend against these threats. The initial step of the immunity signaling pathway is recognition of intra- or extracellular pathogen-derived molecules. Quite remarkably, both plants and animals utilize proteins with similar structures for this purpose. Externally oriented transmembrane-type proteins containing leucine-rich repeat (LRR) domains detect extracellular molecules, whereas cytoplasmic sensors possess nucleotide-binding (NB) and LRR domains. To understand how plants utilize these proteins and how pathogens sabotage the immunity system, we initiated structural analyses of both host immunity-related proteins and pathogen-derived proteins. Recent findings on the structure-based functional analysis of these proteins will be discussed.
