ARA8 — Oryza sativa Japonica

Summary

OsARA8 (also known as PCS1, PCS2, CAD1) on rice chromosome 5 encodes a protein with glutathione gamma-glutamylcysteinyltransferase activity, a phytochelatin synthase family member with a papain-like cysteine peptidase domain. The gene is associated with phytochelatin anabolism, detoxification of cadmium, copper, and arsenic ions, arsenite transport, and defense response via callose deposition. It has been linked to cadmium and arsenite tolerance in rice seedlings and to node-specific expression. Associations also include plant organ development, chlorophyll metabolism, jasmonic acid signaling, and regulation of gene expression. The encoded protein localizes to the plastid, cytosol, and nucleus. Studies of related genes in other species link the family to heavy metal tolerance, pathogen resistance, callose deposition, and seed germination.