Role of a Newly Cloned Alternative Oxidase Gene (BjAOX1a) in Turnip Mosaic Virus (TuMV) Resistance in Mustard
- 269 Downloads
A new alternative oxidase (AOX) gene, designated as BjAOX1a, of mustard (Brassica juncea) was cloned by reverse transcription-polymerase chain reaction (RT-PCR). The full-length cDNA of BjAOX1a was 1,346 bp in size and containing an open reading frame (ORF) of 1,083 bp in size. The predicted amino acid sequence exhibited 82.17% homology to the alternative oxidase of Arabidopsis thaliana. Analysis of functional regions revealed that the BjAOX1a protein contained several metal-binding regions, α-helical regions, and cysteine residues, similar to other AOX1 proteins. Pretreatment of mustard plants with salicylhydroxamic acid (SHAM), an inhibitor of AOX protein, inhibited AOX activity and promoted systemic movement of the coat protein of Turnip mosaic virus (TuMV), whereas pretreatment of plants with antimycin A (AA), a cytochrome pathway inhibitor, inhibited the systemic movement of the coat protein of TuMV. Furthermore, H2O2 and O2− contents were enhanced following SHAM pretreatment. Thus, AOX1 might alleviate reactive oxygen species (ROS) and enhance resistance of mustard plants to TuMV, and could serve as a critical component in TuMV resistance.
KeywordsAlternative oxidase (AOX) Reactive oxygen species Cyanide (CN)-resistant respiration Turnip mosaic virus (TuMV)
We thank Prof. JS. Chen for providing the B strain of TuMV. We also express our gratitude to Dr. X. Li for the measurements of respiratory rate. This work was supported by grants from Trans-Century Fund for the Excellence Talents by the State Education Commission (J20070206).
- Dl P, Ma H, Zhang Y, Ma Y, Wang W, Geng H, Wu J, Li C (2011) Virus-induced gene silencing of a putative glutathione s-transferase gene compromised ol-1-mediated resistance against powdery mildew in tomato. Plant Mol Biol Rep. doi: 10.1007/s11105-011-0331-4
- Dutilleul C, Garmier M, Noctor G, Mathieu C, Chetrit P, Foyer CH, de Paepe R (2003) Leaf mitochondria modulate whole cell redox homeostasis, set antioxidant capacity, and determine stress resistance through altered signaling and diurnal regulation. Plant Cell 15:1212–1226PubMedCrossRefGoogle Scholar
- Gilliland A, Singh DP, Hayward JM, Moore CA, Murphy AM, York CJ, Slator J, Carr JP (2003) Genetic modification of alternative respiration has differential effects on antimycin A induced versus salicylic acid-induced resistance to Tobacco mosaic virus. Plant Physiol 132:1518–1528PubMedCrossRefGoogle Scholar
- Kiraly L, Hafez YM, Fodor J, Kiraly Z (2008) Suppression of Tobacco mosaic virus-induced hypersensitive-type necrotization in tobacco at high temperature is associated with downregulation of NADPH oxidase and superoxide and stimulation of dehydroascorbate reductase. J Gen Virol 89:799–808PubMedCrossRefGoogle Scholar
- Li Y, Zhu L, Xu B, Yang J, Zhang M (2011) Identification of down-regulated genes modulated by an alternative oxidase pathway under cold stress conditions in watermelon plants. Plant Mol Biol Rep. doi: 10.1007/s11105-011-0333-2
- Vidal G, Ribas-Carbo M, Garmier M, Dubertret G, Rasmusson AG, Mathieu C, Foyer CH, De Paepe R (2007) Lack of respiratory chain complex I impairs alternative oxidase engagement and modulates redox signaling during elicitor-induced cell death in tobacco. Plant Cell 19:640–655PubMedCrossRefGoogle Scholar
- Watanabe CK, Hachiya T, Terashima I, Noguchi K (2008) The lack of alternative oxidase at low temperature leads to a disruption of the balance in carbon and nitrogen metabolism, and to an up-regulation of antioxidant defence systems in Arabidopsis thaliana leaves. Plant Cell Environ 31:1190–1202PubMedCrossRefGoogle Scholar