title: Identification of glutathione S-transferase (GST) genes from a dark septate endophytic fungus (Exophiala pisciphila) and their expression patterns under varied metals stress.
abstract: Glutathione S-transferases (GSTs) compose a family of multifunctional enzymes that play important roles in the detoxification of xenobiotics and the oxidative stress response. In the present study, twenty four GST genes from the transcriptome of a metal-tolerant dark septate endophyte (DSE), Exophiala pisciphila, were identified based on sequence homology, and their responses to various heavy metal exposures were also analyzed. Phylogenetic analysis showed that the 24 GST genes from E. pisciphila (EpGSTs) were divided into eight distinct classes, including seven cytosolic classes and one mitochondrial metaxin 1-like class. Moreover, the variable expression patterns of these EpGSTs were observed under different heavy metal stresses at their effective concentrations for inhibiting growth by 50% (EC50). Lead (Pb) exposure caused the up-regulation of all EpGSTs, while cadmium (Cd), copper (Cu) and zinc (Zn) treatments led to the significant up-regulation of most of the EpGSTs (p < 0.05 to p < 0.001). Furthermore, although heavy metal-specific differences in performance were observed under various heavy metals in Escherichia coli BL21 (DE3) transformed with EpGSTN-31, the over-expression of this gene was able to enhance the heavy metal tolerance of the host cells. These results indicate that E. Pisciphila harbored a diverse of GST genes and the up-regulated EpGSTs are closely related to the heavy metal tolerance of E. pisciphila. The study represents the first investigation of the GST family in E. pisciphila and provides a primary interpretation of heavy metal detoxification for E. pisciphila.
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China.
authors.forename: Mi
authors.initials: M
authors.lastname: Shen
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China; School of Agriculture, Yunnan University, Kunming, Yunnan, China.
authors.forename: Da-Ke
authors.initials: DK
authors.lastname: Zhao
authors.affiliation: School of Agriculture, Yunnan University, Kunming, Yunnan, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Qiao
authors.affiliation: School of Life Science, Yunnan University, Kunming, Yunnan, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China.
authors.forename: Jun-Ling
authors.initials: JL
authors.lastname: Wang
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China.
authors.forename: Guan-Hua
authors.initials: GH
authors.lastname: Cao
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: Key Laboratory of Conservation and Utilization for Bioresources and Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, Yunnan, China; School of Agriculture, Yunnan University, Kunming, Yunnan, China.
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Zhao
mesh_terms: D002104:Cadmium / Q000494:pharmacology; D003300:Copper / Q000494:pharmacology; D005093:Exophiala / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects*; D005800:Genes, Fungal; D005982:Glutathione Transferase / Q000235:genetics*; D007854:Lead / Q000494:pharmacology; D019216:Metals, Heavy / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics*; D012989:Soil Pollutants; D015032:Zinc / Q000494:pharmacology
chemical_list: D019216:Metals, Heavy; D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead; D003300:Copper; D005982:Glutathione Transferase; D015032:Zinc