title: A proteomic analysis of green and white sturgeon larvae exposed to heat stress and selenium.
abstract: Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay/Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26 degrees C and micro-injected with Seleno-L-Methionine to reach 8microgg(-)(1) selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P<0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons could indicate early warning signals preceding population decline.
authors.affiliation: Department of Animal Science, University of California, Davis, CA 95616, USA. frederic.silvestre@fundp.ac.be
authors.forename: Frédéric
authors.initials: F
authors.lastname: Silvestre
authors.forename: Javier
authors.initials: J
authors.lastname: Linares-Casenave
authors.forename: Serge I
authors.initials: SI
authors.lastname: Doroshov
authors.forename: Dietmar
authors.initials: D
authors.lastname: Kültz
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D015180:Electrophoresis, Gel, Two-Dimensional; D005399:Fishes / Q000254:growth & development*; D006358:Hot Temperature; D007814:Larva / Q000187:drug effects / Q000378:metabolism*; D040901:Proteomics; D012643:Selenium / Q000633:toxicity*; D013045:Species Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D012643:Selenium