CS1 — Oryza sativa Japonica

Summary

OsCS1 (OS12G0178100) on rice chromosome 12 encodes a haem peroxidase of the Ccp1-like family with L-ascorbate peroxidase activity (EC 1.11.1.11). The gene is associated with diverse biological processes including the ascorbate-glutathione cycle, cellular oxidant detoxification, H₂O₂-mediated signaling, chloroplast-nucleus signaling, and aerenchyma formation. It has been linked to numerous agronomic traits such as plant growth, architecture, height, seed and thousand kernel weight, leaf morphology, tiller angle, days to flowering, and reproductive-stage cold tolerance. Associations also include responses to abiotic stresses (salt, cold, drought, aluminum toxicity, excess light), biotic stresses (blast, bacterial blight, gall midge resistance), and phytohormone pathways (salicylic acid, abscisic acid, jasmonic acid). The protein localizes to chloroplast thylakoid and envelope, peroxisome membrane, and stress granules. Studies of related genes in other species link the family to heat, salt, and oxidative stress tolerance, as well as cold priming-induced pathogen resistance.