An estrogen-responsive plasma protein expression signature in Atlantic cod ( Gadus morhua) revealed by SELDI-TOF MS

• Published in: Ecotoxicology and environmental safety 2011-11, Vol.74 (8), p.2175-2181
• Main Authors: Mæland Nilsen, Mari, Meier, Sonnich, Larsen, Bodil K., Ketil Andersen, Odd, Hjelle, Anne
• Format: Article
• Language: English
• Subjects: adults; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Applied ecology; Atlantic cod; Biological and medical sciences; Biomarkers - blood; Biomarkers - metabolism; blood proteins; Blood Proteins - metabolism; cod (fish); Ecotoxicology; Ecotoxicology, biological effects of pollution; EDC; environmental monitoring; Environmental Monitoring - methods; Estradiol - blood; Estradiol - metabolism; Estrogens - metabolism; Fish Proteins - metabolism; Fundamental and applied biological sciences. Psychology; Gadus morhua; Gadus morhua - blood; Gadus morhua - metabolism; gene expression regulation; General aspects; Gonadal Steroid Hormones - metabolism; Male; Marine; North Sea; oils; Petroleum - metabolism; Phenols - toxicity; principal component analysis; protein synthesis; Proteomics; reproducibility; Reproducibility of Results; Sea water ecosystems; SELDI-TOF MS; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Synecology; Water Pollutants, Chemical - toxicity
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2011.07.036

Compound-specific protein expression signatures (PESs) can be revealed by proteomic techniques. The SELDI-TOF MS approach is advantageous due to its simplicity and high-throughput capacity, however, there are concerns regarding the reproducibility of this method. The aim of this study was to define an estrogen-responsive PES in plasma of Atlantic cod ( Gadus morhua) using the SELDI-TOF MS technique. Protein expression analysis of male cod exposed to 17 β-estradiol (E 2) showed that 27 plasma peaks were differentially expressed following exposure. The reproducibility of this result was evaluated by reanalyzing the samples six months later, and a significant change in expression was confirmed for 13 of the 27 peaks detected in the first analysis. The performance of the reproducible E 2-responsive PES, constituting these 13 peaks, was then tested on samples from juvenile cod exposed to 4-nonylphenol, North Sea oil, or North Sea oil spiked with alkylphenols. Principal component analysis revealed that nonylphenol-exposed cod could be separated from unexposed cod based on the E 2-responsive PES, indicating that the PES can be used to assess estrogenic exposure of both juvenile and adult specimens of cod. A targeted antibody-assisted SELDI-TOF MS approach was carried out in an attempt to identify the E 2-responsive peaks. Results indicated that 2 peaks were fragments of the well-known biomarkers VTG and/or ZRP. In this study, the SELDI-TOF MS technology has shown its potential for defining compound-specific PESs in fish. Nevertheless, thorough validation of reproducibility, specificity and sensitivity of a PES is required before it can be applied in environmental monitoring. ► An estrogen-responsive protein expression signature (PES) was revealed in Atlantic cod. ► The performance of the E 2-responsive PES was validated using samples from an independent study. ► SELDI-TOF MS has a great potential for defining compound-specific PESs in fish.