Cloning, expression and analysis of the olfactory glutathione S-transferases in coho salmon
| Autor: | Herbert M. Espinoza, Laura M. Shireman, William M. Atkins, Valerie McClain, Evan P. Gallagher |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Olfactory system
Models Molecular Blotting Western Molecular Sequence Data Olfaction Biology Biochemistry Polymerase Chain Reaction Catalysis Article 4-Hydroxynonenal chemistry.chemical_compound Oxidoreductase Animals Humans Amino Acid Sequence Cloning Molecular Phylogeny Demethylation DNA Primers Glutathione Transferase Pharmacology chemistry.chemical_classification Base Sequence Sequence Homology Amino Acid Glutathione Oncorhynchus kisutch Molecular biology Amino acid Open reading frame Kinetics chemistry Electrophoresis Polyacrylamide Gel |
| Zdroj: | Biochemical pharmacology. 85(6) |
| ISSN: | 1873-2968 |
| Popis: | The glutathione S-transferases (GSTs) provide cellular protection by detoxifying xenobiotics, maintaining redox status, and modulating secondary messengers, all of which are critical to maintaining olfaction in salmonids. Here, we characterized the major coho salmon olfactory GSTs (OlfGSTs), namely omega, pi, and rho subclasses. OlfGST omega contained an open reading frame of 720 bp and encoded a protein of 239 amino acids. OlfGST pi and OlfGST rho contained open reading frames of 727 and 681 bp, respectively, and encoded proteins of 208 and 226 amino acids. Whole-protein mass spectrometry yielded molecular weights of 29,950, 23,354, and 26,655 Da, respectively, for the GST omega, pi, and rho subunits. Homology modeling using four protein-structure prediction algorithms suggest that the active sites in all three OlfGST isoforms resembled counterparts in other species. The olfactory GSTs conjugated prototypical GST substrates, but only OlfGST rho catalyzed the demethylation of the pesticide methyl parathion. OlfGST pi and rho exhibited thiol oxidoreductase activity towards 2-hydroxyethyl disulfide (2-HEDS) and conjugated 4-hydroxynonenal (HNE), a toxic aldehyde with neurodegenerative properties. The kinetic parameters for OlfGST pi conjugation of HNE were KM = 0.16 ± 0.06 mM and Vmax = 0.5 ± 0.1 μmol min−1 mg−1 for OlfGST pi, whereas OlfGST rho was more efficient at catalyzing HNE conjugation (KM = 0.022 ± 0.008 mM and Vmax = 0.47 ± 0.05 μmol min−1 mg−1). Our findings indicate that the peripheral olfactory system of coho expresses GST isoforms that detoxify certain electrophiles and pesticides and that help maintain redox statusand signal transduction. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect