Involvement of Rice CPR5 in Response to Oxidative Stress

Abstract:

In order to understand the function of CPR5 in rice (Oryza sativa L.), a homologous sequence, named as OsCPR5, was cloned from rice full-length cDNA library by BLAST. Bioinformatics analysis showed that the length of ORF in OsCPR5 was 1551 bp, encoding 516 amino acids. The OsCPR5 protein contained five transmembrane regions at the carboxy terminus, which also existed in AtCPR5. The expression of OsCPR5 was high in roots. The subcellular localization showed that OsCPR5 distributed widely in cell membrane, cytoplasm, and nucleus. The expression of OsCPR5 in rice was up-regulated by different environment stresses, including exogenous abscisic acid (ABA), NaCl, especially methyl viologen (MV) and hydrogen peroxide (H₂O₂). When transgenic lines atcpr5/OsCPR5 of Arabidopsis thaliana were treated with methyl viologen (0.5 μmol L^-1, 1.0 μmol L^-1) and hydrogen peroxide (6 mmol L^-1, 8 mmol L^-1), the seed germination rates were higher than that of atcpr5 mutant. Therefore, it was suggested that OsCPR5 played a role in response to oxidative stress.

Key words:Rice;OsCPR5;Methyl viologen;Hydrogen peroxide;Oxidative stress