ARA8 — Brassica juncea

Summary

BjARA8 (BJUB04G43200S) on chromosome B04 of Indian mustard encodes a phytochelatin synthase, a papain-like cysteine peptidase superfamily member with phytochelatin synthase C-terminal and N-terminal domains. The enzyme exhibits glutathione gamma-glutamylcysteinyltransferase activity, arsenite-transporting ATPase activity, and ABC-type phytochelatin transporter activity, and binds cadmium, copper, and other metals. It is associated with phytochelatin biosynthesis, cellular detoxification of cadmium and copper ions, arsenite transport, indole glucosinolate catabolism, defense response by callose deposition, and response to arsenic, cadmium, and bacterial pathogens. The gene is linked to auxin content, immune signaling, osmotic stress tolerance, and arsenic translocation. Studies of related genes in other species connect the family to heavy metal tolerance and accumulation, arsenic detoxification, pathogen resistance, and callose deposition.