Unravelling mitochondrial retrograde regulation in the abiotic stress induction of rice ALTERNATIVE OXIDASE 1 genes

• Published in: Plant, cell and environment cell and environment, 2013-04, Vol.36 (4), p.775-788
• Main Authors: LI, CHUN‐RONG, LIANG, DAN‐DAN, LI, JUAN, DUAN, YONG‐BO, LI, HAO, YANG, YA‐CHUN, QIN, RUI‐YING, LI, LI, WEI, PENG‐CHENG, YANG, JIAN‐BO
• Format: Article
• Language: English
• Subjects: alternative oxidase; Biological and medical sciences; Calcium - metabolism; Cell Nucleus - metabolism; Cold Temperature; Droughts; Free Radical Scavengers - pharmacology; Fundamental and applied biological sciences. Psychology; Gene Expression; Gene Expression Regulation, Plant; Hydrogen peroxide; Hydrogen Peroxide - pharmacology; Mitochondria - enzymology; Mitochondria - physiology; Mitochondrial Proteins - drug effects; Mitochondrial Proteins - genetics; Mitochondrial Proteins - metabolism; Oryza - drug effects; Oryza - enzymology; Oryza - genetics; Oryza - physiology; Oryza sativa; Oxidative Stress; Oxidoreductases - drug effects; Oxidoreductases - genetics; Oxidoreductases - metabolism; Paraquat - pharmacology; Plant Proteins - drug effects; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified; reactive oxygen species; Reactive Oxygen Species - pharmacology; Salinity; Seedlings - drug effects; Seedlings - enzymology; Seedlings - genetics; Seedlings - physiology; Signal Transduction; Stress, Physiological; Superoxide Dismutase - genetics; Superoxide Dismutase - metabolism; superoxide ion; Superoxides - analysis; Superoxides - pharmacology
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.12013

ABSTRACT Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. It is not clear whether MRR is a common regulation mechanism in plant abiotic stress response. In this study, we analysed the early abiotic stress response of the rice OsAOX1 genes, and the induction of OsAOX1a and OsAOX1b (OsAOX1a/b) was selected as a working model for the stress‐induced MRR studies. We found that the induction mediated by the superoxide ion (O2·‐)‐generating chemical methyl viologen was stronger than that of hydrogen peroxide (H2O2). The addition of reactive oxygen species (ROS) scavengers demonstrated that the stress induction was reduced by eliminating O2·‐. Furthermore, the stress induction did not rely on chloroplast‐ or cytosol‐derived O2·‐. Next, we generated transgenic plants overexpressing the superoxide dismutase (SOD) gene at different subcellular locations. The results suggest that only the mitochondrial SOD, OsMSD, attenuated the stress induction of OsAOX1a/b specifically. Therefore, our findings demonstrate that abiotic stress initiates the MRR on OsAOX1a/b and that mitochondrial O2·– is involved in the process. Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. Here, we showed the stress induction of MRR model gene AOX1 could be attenuated by a Mitochondrial superoxide dismutase in rice. Our results suggested the plants could initiate MRR in response to abiotic stress.