This family of proteins is found in eukaryotes. Proteins in this family are typically between 251 and 588 amino acids in length. The family is found in association with Pfam:PF00023, Pfam:PF00651. There are two conserved sequence motifs: LENRV and DLN. NPR1 (NIM1) is a defence protein in many plant species.

1: Arabidopsis thaliana genes encoding defense signaling and recognition proteins exhibit contrasting evolutionary dynamics. Caldwell KS, Michelmore RW; Genetics. 2009;181:671-684. PMID:19064707