InterPro domain: IPR044292

This entry represents a group of plant regulatory proteins, including NPR1-4 from Arabidopsis. NPR1 is a central regulator of salicylic-acid (SA)-mediated defense signaling in Arabidopsis. It contains a BTB/POZ domain at the N-terminal and an ankyrin-repeat domain in the central region. It binds to TGA1, a member of the TGA family of transcription factors that activate SA-responsive elements in the promoters of PR (PATHOGENESIS-RELATED) genes. It also has cytosolic function in cross-communication between SA- and JA-dependent defense signaling pathways [ 1 ]. NPR1 is functionally conserved in diverse plant species, including rice (Oryza sativa L.) [ 2 ]. NPR3 and NPR4 have also been shown to be required for basal defense against pathogens [ 3 , 4 ].

1. NPR1: the spider in the web of induced resistance signaling pathways. Curr Opin Plant Biol 7, 456-64
2. Functional analysis of rice NPR1-like genes reveals that OsNPR1/NH1 is the rice orthologue conferring disease resistance with enhanced herbivore susceptibility. Plant Biotechnol J 5, 313-24
3. An Arabidopsis NPR1-like gene, NPR4, is required for disease resistance. Plant J 41, 304-18
4. Negative regulation of defense responses in Arabidopsis by two NPR1 paralogs. Plant J 48, 647-56