Participation of the inositol phospholipid signaling pathway in the increase in cytosolic calcium induced by tributyltin chloride intoxication of chlorophyllous protozoa Euglena gracilis Z and its achlorophyllous mutant SM-ZK

• Published in: Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology Vol. 146; no. 4; pp. 525 - 530
• Main Authors: Ohta, Mari, Suzuki, Tetsuya
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2007; Elsevier BV
• Subjects: 1,4,5-trisphosphate; 1303 Biochemistry; 1307 Cell Biology; 1314 Physiology; 2307 Health; 3005 Toxicology; Animals; Biochemistry & Molecular Biology; Ca2; Calcimycin; Calcimycin - pharmacology; Calcium; Calcium - antagonists & inhibitors; Calcium - metabolism; Chlamydomonas-reinhardtii; Chlorophyll; Chlorophyll - deficiency; Chlorophyll - genetics; Chlorophyll - metabolism; Cytosol; Cytosol - drug effects; Cytosol - metabolism; Deflagellation; Endocrinology & Metabolism; Enzyme Inhibitors; Enzyme Inhibitors - pharmacology; Euglena gracilis; Euglena gracilis - drug effects; Euglena gracilis - genetics; Euglena gracilis - metabolism; Flagella; Flagella - drug effects; Flagella - pathology; Induced Cellular-damage; Inositol triphosphate; Intercellular Signaling Peptides and Proteins; Intracellular Ca 2; intracellular Ca2; Involvement; Mastoparan; Morphological alteration; Mutation; Neomycin; Neomycin - pharmacology; Peptides; Peptides - pharmacology; Phosphatidylinositols; Phosphatidylinositols - metabolism; Responses; Signal Transduction; Stress; Toxicology; Toxicology and Mutagenesis; Transduction; Trialkyltin Compounds; Trialkyltin Compounds - toxicity; Tributyltin; Verapamil; Verapamil - pharmacology; Wasp Venoms; Wasp Venoms - pharmacology; Water; Water Pollutants, Chemical; Water Pollutants, Chemical - toxicity; Zoology; Signal transduction; Inositol triphosphate; Mastoparan; Euglena gracilis; Morphological alteration; Neomycin; Tributyltin; Intracellular Ca 2
• ISSN: 1532-0456; 1878-1659
• DOI: 10.1016/j.cbpc.2007.06.005

Exposure of tri- n-butyl tin chloride (TBTCl) as a stressor to Euglena gracilis Z causes rapid alteration of cell morphology followed by deflagellation. The present study was undertaken to reveal the mechanism of the cell response at a molecular level. Chlamydomonas reinhardtii, in this study E. gracilis Z and its achlorophyllous mutant SM-ZK, gave similar results when subject to the same stressor. Indeed, similar results were obtained with both strains. Next, assuming that the morphological alteration caused by TBTCl is mediated by the inositide phosphate-lipid signaling pathway, the effects of signal transduction and Ca 2+ release reagents (mastoparan as a G-protein activator, neomycin as a phospholipase C inhibitor, verapamil as a Ca 2+ channel blocker, and A23187 as a Ca 2+ ionophore) on morphology and intracellular Ca 2+ levels were examined with or without TBTCl. The data strongly suggest that the morphological alteration is mediated by an increase in Ca 2+ linked to the inositol phosphatide pathway. The cellular response to signal transduction inducing reagents was compared between the E. gracilis chlorophyllous Z strain and its achlorophyllous mutant SM-ZK strain. Significant differences were observed between the Z and SM-ZK strains in terms of the stress response and intracellular Ca 2+ level.