Immunodetection of hepatic peroxisomal PMP70 as an indicator of peroxisomal proliferation in the mummichog, Fundulus heteroclitus.
Peroxisomes are important sites for beta-oxidative fatty acid metabolism and peroxidative detoxification. Agents causing peroxisomal proliferation have been associated with reproductive and developmental toxicity and hepatocarcinogenesis. Female mummichog (Fundulus heteroclitus) were exposed to waterborne 2,4-dichlorophenoxyacetic acid (2,4-D), a model peroxisome proliferator, at sublethal concentrations of 0.01, 0.10, and 1.00 ppm or dimethyl sulfoxide (DMSO) vehicle for 7, 14, or 21 days. A polyclonal antibody to rat PMP70 protein (70 kDa peroxisomal membrane protein, a major component of peroxisomes and member of the ABC transporter superfamily) was used for Western blotting after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to determine possible peroxisome proliferation. Significant increases of an approximately 70-kDa protein band recognized by anti-PMP70 were observed on all days, especially at the highest exposure concentration. The data suggest that immunoassay of PMP70 is a useful biomarker assay for peroxisome proliferation, and may be applicable to a wide range of species. The response also suggests that this assay could be used for measuring chronic exposures to environmental peroxisome proliferating agents.
Ackers
J T
JT
Chesapeake Biological Laboratory, Program in Toxicology, University of Maryland Center for Environmental Science, PO Box 38, One Williams Street, Solomons, MD 20688-0038, USA.
Johnston
M F
MF
Haasch
M L
ML
D015084:2,4-Dichlorophenoxyacetic Acid / Q000633:toxicity*; D018528:ATP-Binding Cassette Transporters; D000818:Animals; D015415:Biomarkers; D015153:Blotting, Western / Q000662:veterinary; D004121:Dimethyl Sulfoxide; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005260:Female; D007695:Killifishes / Q000378:metabolism*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008565:Membrane Proteins / Q000032:analysis*; D020675:Peroxisomes / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
D018528:ATP-Binding Cassette Transporters; C489272:Abcd3 protein, rat; D015415:Biomarkers; D008565:Membrane Proteins; D015084:2,4-Dichlorophenoxyacetic Acid; D004121:Dimethyl Sulfoxide