title: Cloning, expression and identification of two glutathione S-transferase isoenzymes from Perna viridis.
abstract: Glutathione S-transferases (GSTs; EC 2.5.1.18) are phase II enzymes involved in major detoxification reactions of xenobiotic in many organisms. In the present study, two classes of GSTs (PvGST1 and PvGST2) were cloned from P. viridis by rapid amplification of cDNA ends method. Sequence alignments and phylogenetic analysis together supported that PvGST1 and PvGST2 belonged to the pi and omega classes, respectively. The PvGST1 cDNA was 1214 nucleotides (nt) in length and contained a 618 nt open reading frame (ORF) encoding 206 amino acid residues, and had 46 nt of 5'-untranslated region (UTR) and a 3' UTR of 550 nt including a tailing signal (AATAAA) and a poly (A) tail. The molecular mass of the predicted PvGST1 was 23.815kDa, with the calculated isoelectric point being 5.39. PvGST2 was 1093bp, consisting of a 5' UTR of 13bp, a 3' UTR of 246bp and an ORF of 834bp. The deduced protein was composed of 278 amino acids, with an estimated molecular mass of 32.476kDa and isoelectric point of 8.88. Tissue distribution analysis of the PvGST1 and PvGST2 mRNA revealed that the GST expression level was higher in digestive gland and gonad, while lower in gill and mantle in both genders. Molecular modeling analysis of two GSTs implicated their various functions account for their different enzymatic features.
authors.affiliation: State Key Laboratory of Marine Environmental Science, Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of Environment and Ecology, Xiamen University, Xiamen 361005, China. lzz680@163.com
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Li
authors.forename: Rong
authors.initials: R
authors.lastname: Chen
authors.forename: Zhenghong
authors.initials: Z
authors.lastname: Zuo
authors.forename: Zhengping
authors.initials: Z
authors.lastname: Mo
authors.forename: Ang
authors.initials: A
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D000704:Analysis of Variance; D000818:Animals; D001483:Base Sequence; D052160:Benzothiazoles; D049872:Bivalvia / Q000201:enzymology*; D003001:Cloning, Molecular; D016000:Cluster Analysis; D018076:DNA, Complementary / Q000235:genetics; D003959:Diamines; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics / Q000502:physiology*; D005982:Glutathione Transferase / Q000235:genetics* / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000235:genetics; D009930:Organic Chemicals; D010802:Phylogeny; D011487:Protein Conformation; D011804:Quinolines; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D052160:Benzothiazoles; D018076:DNA, Complementary; D003959:Diamines; D007527:Isoenzymes; D009841:Oligonucleotides; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I; D005982:Glutathione Transferase