title: Histopathological effect and stress response of mantle proteome following TBT exposure in the Hooded oyster Saccostrea cucullata.
abstract: Tributyltin (TBT), an environmental pollutant in marine ecosystems, is toxic to organisms. Although contamination by and bioaccumulation and toxicity of this compound have been widely reported, its underlying molecular mechanisms remain unclear. In the present study, we exposed the Hooded oyster Saccostrea cucullata to TBT to investigate histopathological effects and proteome stress response. Animals were exposed to three TBT sub-lethal concentrations, 10, 50 and 150 μg/l for 48 h. TBT produced stress leading to histopathological changes in oyster tissues including mantle, gill, stomach and digestive diverticula. TBT induced mucocyte production in epithelia and hemocyte aggregation in connective tissue. Cell necrosis occurred when exposure dosages were high. Comparative proteome analyses of mantle protein of oysters exposed to 10 μg/l and control animals were analyzed by a 2-DE based proteomic approach. In total, 32 protein spots were found to differ (p < 0.05). Of these, 17 proteins were identified which included 14 up-regulated and 3 down-regulated proteins. TBT induced the expression of proteins involved in defensive mechanisms (HSP-78, HSP-70, aldehyde dehydrogenase and catalase), calcium homeostasis (VDAC-3), cytoskeleton and cytoskeleton-associated proteins, energy metabolism and amino acid metabolism. Our study revealed that TBT disturbs calcium homeostasis via VDAC-3 protein in mantle and this probably is the key molecular mechanism of TBT acting to distort shell calcification. Moreover, proteins involved in cell structure (tubulin-alpha and tubulin-beta) and protein synthesis were reduced after TBT exposure. Additionally, differential proteins obtained from this work will be useful as potential TBT biomarkers.
authors: Faculty of Education, Burapha University, Bangsean Road, Chonburi 20131, Thailand.
authors: Phattirapa
authors: P
authors: Khondee
authors: Laboratory of Biochemistry, Chulabhorn Research Institute, Vibhavadi-Rangsit Highway, Bangkok 10210, Thailand.
authors: Chantragan
authors: C
authors: Srisomsap
authors: Laboratory of Biochemistry, Chulabhorn Research Institute, Vibhavadi-Rangsit Highway, Bangkok 10210, Thailand.
authors: Daranee
authors: D
authors: Chokchaichamnankit
authors: Laboratory of Biochemistry, Chulabhorn Research Institute, Vibhavadi-Rangsit Highway, Bangkok 10210, Thailand; Department of Biochemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors: Jisnuson
authors: J
authors: Svasti
authors: La Trobe Institute for Molecular Science (LIMS), La Trobe University, Bundoora Victoria 3086, Australia.
authors: Richard J
authors: RJ
authors: Simpson
authors: Department of Biology, Faculty of Science, Burapha University, Bangsean Road, Chonburi 20131, Thailand. Electronic address: sutin@buu.ac.th.
authors: Sutin
authors: S
authors: Kingtong
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D003238:Connective Tissue / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D006706:Homeostasis / Q000187:drug effects; D010125:Ostreidae / Q000187:drug effects* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics; D014220:Trialkyltin Compounds / Q000032:analysis / Q000633:toxicity*; D050994:Voltage-Dependent Anion Channels / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D020543:Proteome; D014220:Trialkyltin Compounds; D050994:Voltage-Dependent Anion Channels; D014874:Water Pollutants, Chemical; C011559:tributyltin; D002118:Calcium
keywords: Biomarker; Calcium homeostasis; Cytoskeleton; Histopathological effect; Tributyltin