title: Functional analysis of the glutathione S-transferase 3 from Onchocerca volvulus (Ov-GST-3): a parasite GST confers increased resistance to oxidative stress in Caenorhabditis elegans.
abstract: This study examined the genomic organisation of the coding region of the glutathione S-transferase 3 (Ov-GST-3) from the human parasitic nematode Onchocerca volvulus; alternative splicing leads to three different transcripts (Ov-GST-3/1; Ov-GST-3/2 and Ov-GST-3/3). Since the expression of Ov-GST-3 is inducible by oxidative stress, it is assumed that it is involved in the defense against reactive oxygen species (ROS) resulting from cellular metabolism. Furthermore, we suggest that Ov-GST-3 plays an important role in the protection of the parasite against ROS derived from the host's immune system. To experimentally investigate these speculations, we generated Caenorhabditis elegans lines transgenic for Ov-GST-3 (AK1) and examined their resistance to artificially generated ROS. The AK1 worms (extrachromosomal and integrated lines) were found to be much more resistant to internal (juglone) and external (hypoxanthine/xanthine oxidase) oxidative stress than wild-type C.elegans worms. RNA interference experiments targeted to the Ov-GST-3 transcripts resulted in decreased resistance, confirming that this effect is due to the transgenic expression of Ov-GST-3. These results clearly demonstrate that the Ov-GST-3 gene confers an increased resistance to oxidative stress. This study also shows the applicability of C.elegans as a model organism for the functional characterization of genes from (parasitic) nematode species which are not accessible to genetic manipulations.
authors.affiliation: Institut für Genetik, Heinrich-Heine-Universitat, Universitätsstrasse 1, 40225 Dusseldorf, Germany. kampkoet@uni-duesseldorf.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Kampkötter
authors.forename: Thorsten E
authors.initials: TE
authors.lastname: Volkmann
authors.forename: Sarah Hegi
authors.initials: SH
authors.lastname: de Castro
authors.forename: Britta
authors.initials: B
authors.lastname: Leiers
authors.forename: Lars Oliver
authors.initials: LO
authors.lastname: Klotz
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Johnson
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Link
authors.forename: Kimberly
authors.initials: K
authors.lastname: Henkle-Dührsen
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism*; D005982:Glutathione Transferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008136:Longevity / Q000235:genetics; D008969:Molecular Sequence Data; D017181:Onchocerca volvulus / Q000201:enzymology* / Q000235:genetics; D018384:Oxidative Stress; D034622:RNA Interference; D012330:RNA, Double-Stranded / Q000235:genetics / Q000378:metabolism; D018510:RNA, Helminth / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D019076:Transgenes / Q000235:genetics
chemical_list: D012330:RNA, Double-Stranded; D018510:RNA, Helminth; D017382:Reactive Oxygen Species; D005982:Glutathione Transferase