ABSTRACT
Applied to environmental toxicology, proteome analysis may be used to isolate chemical-specific protein expression signatures (PES). In this project specific PES were isolated in mussels, Mytilus edulis, from the Baltic Sea subjected in the laboratory to treatment with copper (70 ppb), Aroclor 1248 (1 ppb), and to lowered salinity. Four mussels in each treatment group were acclimated in the laboratory for 24 h before beginning the 7-day exposure. Whole body tissue was homogenized and separated using two-dimensional gel electrophoresis. The protein gels were scanned to TIFF files and compared using MELANIE II 2D gel analysis software (BioRad). Protein expression signatures including proteins induced and repressed by exposure were isolated for each treatment group. The specificity of PES due to environmental changes shows promise in bioindication, toxicity testing and in helping identify possible toxicity mechanisms.
Subject(s)
Bivalvia/drug effects , Copper/toxicity , Polychlorinated Biphenyls/toxicity , Protein Biosynthesis , Sodium Chloride/toxicity , Toxicology/methods , Animals , Aroclors/toxicity , Electrophoresis, Gel, Two-Dimensional , Sodium Chloride/administration & dosageABSTRACT
Protein expression and lysosomal stability were observed in Mytilus edulis exposed to 0, 20, 40, 60, and 80 ppb copper sulfate for 24 h in a static exposure system. Haemolymph was removed from each mussel and analyzed for lysosomal damage using the Neutral Red retention assay expressed as the ratio of lysosomal size to cell area, the lysosomal destabilization ratio. Gill tissue from the same individuals was dissected, homogenized and the proteins extracted and then separated using two-dimensional gel electrophoresis. Two-dimensional protein maps from each concentration were analyzed using MELANIE II 2D gel analysis software (Biorad). Lysosomal damage increased with each dosage, with LDRs ranging from 0.18 +/- 0.01 at 0 ppb copper sulfate to 0.32 +/- 0.11 at 80 ppb copper sulfate. Orthogonal comparisons showed that the control, 20 and 40 ppb classes together differed significantly (P < 0.05) from the 60 and 80 ppb classes together. Specific protein expression signatures were identified at each dosage.
Subject(s)
Bivalvia/drug effects , Copper Sulfate/toxicity , Lysosomes/drug effects , Protein Biosynthesis , Animals , Bivalvia/metabolism , Electrophoresis, Gel, Two-Dimensional , Gills/chemistry , Gills/drug effects , Lysosomes/metabolismABSTRACT
The macrophage cell lineage continually arises from hematopoietic stem cells during embryonic, fetal, and adult life. Previous theories proposed that macrophages are the recent progeny of bone marrow-derived monocytes and that they function primarily in phagocytosis. More recently, however, observations have shown that the ontogeny of macrophages in early mouse and human embryos is different from that occurring during adult development, and that the embryonic macrophages do not follow the monocyte pathway. Fetal macrophages are thought to differentiate from yolk sac-derived primitive macrophages before the development of adult monocytes. Further support for a separate lineage of fetal macrophages has come from studies of several species, including chicken, zebrafish, Xenopus, Drosophila, and C. elegans. The presence of fetal macrophages in PU.1-null mice indicates their independence from monocyte precursors and their existence as an alternative macrophage lineage.
