title: Cloning, expression and characterization of mitochondrial manganese superoxide dismutase from the Whitefly, Bemisia tabaci.
abstract: A mitochondrial manganese superoxide dismutase from an invasive species of the whitefly Bemisia tabaci complex (Bt-mMnSOD) was cloned and analyzed. The full length cDNA of Bt-mMnSOD is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. Compared with various vertebrate and invertebrate animals, the MnSOD signature (DVWEHAYY) and four conserved amino acids for manganese binding (H54, H102, D186 and H190) were observed in Bt-mMnSOD. Recombinant Bt-mMnSOD was  overexpressed in Escherichia coli, and the enzymatic activity of purified mMnSOD was assayed under various temperatures. Quantitative real-time PCR analysis with whiteflies of different development stages showed that the mRNA levels of Bt-mMnSOD were significantly higher in the 4th instar than in other stages. In addition, the in vivo activities of MnSOD in the whitefly were measured under various conditions, including exposure to low (4 °C) and high (40 °C) temperatures, transfer from a favorable to an unfavorable host plant (from cotton to tobacco) and treatment with pesticides. Our results indicate that the whitefly MnSOD plays an important role in cellular stress responses and anti-oxidative processes and that it might contribute to the successful worldwide distribution of the invasive whitefly.
authors.affiliation: Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China. xwwang@zju.edu.cn.
authors.forename: Xian-Long
authors.initials: XL
authors.lastname: Gao
authors.forename: Jun-Min
authors.initials: JM
authors.lastname: Li
authors.forename: Yong-Liang
authors.initials: YL
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Jiu
authors.forename: Gen-Hong
authors.initials: GH
authors.lastname: Yan
authors.forename: Shu-Sheng
authors.initials: SS
authors.lastname: Liu
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Wang
mesh_terms: D020816:Amino Acid Motifs / Q000235:genetics; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D003001:Cloning, Molecular; D004795:Enzyme Stability; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D006430:Hemiptera / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008345:Manganese / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics* / Q000378:metabolism; D013696:Temperature
chemical_list: D019476:Insect Proteins; D024101:Mitochondrial Proteins; D011994:Recombinant Proteins; D008345:Manganese; D013482:Superoxide Dismutase