Defense response by NBS-LRR proteins (NLRs) is a sophisticated strategy
that induces effector-triggered immunity (ETI). The NBS-LRR proteins are encoded by
one of the largest and most important gene families involved in disease resistance in
plants. These NBS-LRR proteins are mainly intracellular, and they can specifically
recognize effectors secreted by pathogens either directly or indirectly. This will trigger
downstream signaling pathways leading to implementation of plant defense response
against various classes of pathogens including bacterial, fungal, viral, nematode and
insect. In the present chapter we discuss about the present knowledge pertaining to
NBS-LRR class of proteins; their structural organization, genomic ditribution and
evolution.
Keywords: CNL, Coiled-Coil domain (CC), Gene duplication, LRR (LeucineRich Repeats), Nucleotide-Binding Site (NBS), TNL, Toll Interleukin Receptor
(TIR).