NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) and some NPR1-related proteins are sensitive to salicylic acid.

NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1; also known as NIM1) is a master regulator of systemic acquired resistance (SAR). SAR is induced by salicylic acid (SA), leading to the expression of PATHOGENESIS-RELATED (PR) genes. Current evidence suggests that NPR1 is part of a transcription complex tethered to activation sequence-1 (as-1)-like cis-acting elements in PR-1 gene promoters through TGA transcription factors, and that SA-dependent PR-1 gene expression is regulated by NIM1-INTERACTING (NIMIN) proteins.

Tobacco NIMIN2 proteins control PR gene induction through transient repression early in systemic acquired resistance.

NPR1 (for Nonexpressor of PR genes; also known as NIM1) is a positive regulator of systemic acquired resistance (SAR) in Arabidopsis, which controls the induction of Pathogenesis-Related (PR) genes by salicylic acid (SA). NPR1 interacts with members of two protein families, TGA transcription factors and NIMIN (for NIM1-interacting) proteins. In Arabidopsis, NIMIN1, NIMIN2 and NIMIN3 constitute a small gene family of structurally related, yet distinct members.