title: Molecular cloning, characterization and positively selected sites of the glutathione S-transferase family from Locusta migratoria.
abstract: Glutathione S-transferases (GSTs) are multifunctional enzymes that are involved in the metabolism of endogenous and exogenous compounds and are related to insecticide resistance. The purpose of this study was to provide new information on the molecular characteristics and the positive selection of locust GSTs. Based on the transcriptome database, we sequenced 28 cytosolic GSTs and 4 microsomal GSTs from the migratory locust (Locusta migratoria). We assigned the 28 cytosolic GSTs into 6 classes--sigma, epsilon, delta, theta, omega and zeta, and the 4 microsomal GSTs into 2 subclasses--insect and MGST3. The tissue- and stage-expression patterns of the GSTs differed at the mRNA level. Further, the substrate specificities and kinetic constants of the cytosolic GSTs differed markedly at the protein level. The results of likelihood ratio tests provided strong evidence for positive selection in the delta class. The result of Bayes Empirical Bayes analysis identified 4 amino acid sites in the delta class as positive selection sites. These sites were located on the protein surface. Our findings will facilitate the elucidation of the molecular characteristics and evolutionary aspects of insect GST superfamily.
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Xueyao
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Wang
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Guohua
authors.initials: G
authors.lastname: Qin
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Daqi
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Entomology, Kansas State University, Manhattan, Kansas, United States of America.
authors.forename: Kun Yan
authors.initials: KY
authors.lastname: Zhu
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Enbo
authors.initials: E
authors.lastname: Ma
authors.affiliation: Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi, China.
authors.forename: Jianzhen
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D015153:Blotting, Western; D003001:Cloning, Molecular; D005982:Glutathione Transferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D048188:Locusta migratoria / Q000201:enzymology* / Q000235:genetics; D008958:Models, Molecular; D009928:Organ Specificity; D010802:Phylogeny; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D019476:Insect Proteins; D012333:RNA, Messenger; D005982:Glutathione Transferase