Key positive factor of disease resistance (PubMed:15986920, Ref.2). Involved in defense response against the bacterial blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo). Plants over-expressing NPR1/NH1 acquire high levels of resistance to Xoo, express constitutively defense genes and develop lesion-mimic spots on leaves at pre-flowering stage (PubMed:15986920). Involved in basal resistance to the blast pathogen Magnaporthe oryzae. Plants over-expressing NPR1/NH1 have increased resistance to M.oryzae infection (Ref.2). Plays an essential role in benzothiadiazole (BTH)-induced resistance to the blast fungus disease caused by Magnaporthe oryzae (By similarity). Functions as a transcriptional coactivator of TGA2.1 and LG2 in vitro (By similarity). Involved in defense response against herbivore. Plants silencing NPR1/NH1 have increased herbivore-induced trypsin proteinase inhibitors and volatiles, which reduces the performance of the striped stem borer (SSB) Chilo suppressalis (By similarity). Oligomer in an uninduced state; disulfide-linked. Forms activated monomer upon changes in cellular redox potential (By similarity). Interacts with TGA2.2 (Ref.2). Interacts with NRR (PubMed:16115061). Accumulation in nucleus when present as monomer.