title: Cytochrome P4501A mRNA and protein induction in striped bass (Morone saxatilis).
abstract: The striped bass (Morone saxatilis) supports a valuable recreational fishery and is among the most important piscivorous fish of the San Francisco Estuary. This species has suffered a significant decline in numbers over the past decades, and there is indication that contaminants are important contributors. Polycyclic aromatic hydrocarbons (PAHs) and polyhalogenated aromatic hydrocarbons (PHAHs) including PCBs and dioxins are widespread in the estuary, they typically bioaccumulate through trophic levels, reaching highest levels in top predators and are known to affect the fish health and development. The aim of this study was to investigate the dynamics of cytochrome P4501A (Cyp1a) induction simultaneously at different levels of biological organization (RNA transcription and protein synthesis) as a biomarker of exposure to PAHs and PHAHs. We utilized β-naphthoflavone (BNF) as a model PAH to induce Cyp1a responses in juvenile striped bass in both dose-response and time-response assessments and determined Cyp1a mRNA and protein levels. Significant responses were measured in both systems at 10 mg ΒΝF kg⁻¹, a concentration used for time-response studies. Messenger RNA levels peaked at 6 h post-injection, while protein levels increased progressively with time, significantly peaking at 96 h post-injection; both remaining elevated throughout the duration of the test (8 days). Our data suggest that rapid induction of gene transcription following exposure and subsequent cumulative protein synthesis could provide a useful means of identifying temporal variants in exposure to Cyp1a inducers in Morone saxatilis. The potential application of this combined Cyp1a gene and protein biomarker in this species for field studies is discussed.
authors.affiliation: Pathobiology, Conservation and Population Biology Laboratory, John Muir Institute of the Environment, Center for Watershed Sciences, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA. durieux@univ-corse.fr.|UMR 6134 Sciences Pour l'Environnement, Université de Corse Pasquale Paoli, BP 52, 20250, Corte, France. durieux@univ-corse.fr.
authors.forename: Eric D H
authors.initials: EDH
authors.lastname: Durieux
authors.affiliation: Aquatic Toxicology Laboratory, School of Veterinary Medicine, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, CA, 95616, USA.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Connon
authors.affiliation: Aquatic Toxicology Laboratory, School of Veterinary Medicine, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, CA, 95616, USA.|Swiss Centre for Applied Ecotoxicology, Eawag/EPFL, Überlandstrasse 133, 8600, Dübendorf, Switzerland.
authors.forename: Inge
authors.initials: I
authors.lastname: Werner
authors.affiliation: Aquatic Toxicology Laboratory, School of Veterinary Medicine, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, CA, 95616, USA.|University of California Medical Center, 10535 Hospital Way, Mather, CA, 95616, USA.
authors.forename: Leandro S
authors.initials: LS
authors.lastname: D'Abronzo
authors.affiliation: Pathobiology, Conservation and Population Biology Laboratory, John Muir Institute of the Environment, Center for Watershed Sciences, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA.
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Fitzgerald
authors.affiliation: Pathobiology, Conservation and Population Biology Laboratory, John Muir Institute of the Environment, Center for Watershed Sciences, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA.|Department of Toxic Substances Control, 8800 Cal Center Drive, Sacramento, CA, 95826, USA.
authors.forename: Jimmy L
authors.initials: JL
authors.lastname: Spearow
authors.affiliation: Pathobiology, Conservation and Population Biology Laboratory, John Muir Institute of the Environment, Center for Watershed Sciences, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA.|Ostrach Consulting, 18671 County Road 96, Woodland, CA, 95695, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Ostrach
mesh_terms: D000818:Animals; D001492:Bass / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring; D029941:Fish Proteins / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000633:toxicity; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors; D015262:Xenobiotics / Q000633:toxicity; D019324:beta-Naphthoflavone / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D029941:Fish Proteins; D011084:Polycyclic Aromatic Hydrocarbons; D012333:RNA, Messenger; D015262:Xenobiotics; D019324:beta-Naphthoflavone; D003577:Cytochrome P-450 Enzyme System