title: Molecular characterization and oxidative stress response of an intracellular Cu/Zn superoxide dismutase (CuZnSOD) of the whitefly, Bemisia tabaci.
abstract: Superoxide dismutases (SODs) are important for the survival of insects under environmental and biological stresses; however, little attention has been devoted to the functional characterization of SODs in whitefly. In this study, an intracellular copper/zinc superoxide dismutase of whitefly (Bemisia tabaci) (Bt-CuZnSOD) was cloned. Sequence analysis indicated that the full length cDNA of Bt-CuZnSOD is of 907 bp with a 471 bp open reading frame encoding 157 amino acids. The deduced amino acid sequence shares common consensus patterns with the CuZnSODs of various vertebrate and invertebrate animals. Phylogenetic analysis revealed that Bt-CuZnSOD is grouped together with intracellular CuZnSODs. Bt-CuZnSOD was then over-expressed in E. coli and purified using GST purification system. The enzymatic activity of purified Bt-CuZnSOD was assayed under various temperatures. When whiteflies were exposed to low (4°C) and high (40°C) temperatures, the in vivo activity of Bt-CuZnSOD was significantly increased. Furthermore, we measured the activities of several antioxidant enzymes, including SOD, catalase and peroxidase, in the whitefly after transferring the whitefly from cotton to tobacco (an unfavorable host plant). We found that the activity of SOD increased rapidly on tobacco plant. Taken together, these results suggest that the Bt-CuZnSOD plays a major role in protecting the whitefly against various stress conditions.
authors.affiliation: Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou, China.
authors.forename: Jun-Min
authors.initials: JM
authors.lastname: Li
authors.forename: Yun-Lin
authors.initials: YL
authors.lastname: Su
authors.forename: Xian-Long
authors.initials: XL
authors.lastname: Gao
authors.forename: Jiao
authors.initials: J
authors.lastname: He
authors.forename: Shu-Sheng
authors.initials: SS
authors.lastname: Liu
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002374:Catalase / Q000378:metabolism; D003001:Cloning, Molecular; D005260:Female; D015870:Gene Expression; D006430:Hemiptera / Q000201:enzymology* / Q000235:genetics; D006790:Host-Parasite Interactions; D019476:Insect Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D018384:Oxidative Stress; D009195:Peroxidase / Q000378:metabolism; D010802:Phylogeny; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013482:Superoxide Dismutase / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D013696:Temperature
chemical_list: D019476:Insect Proteins; D011994:Recombinant Proteins; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase