Diesel fuel water-accommodated fraction (diesel-WAF) is a complex mixture of organic compounds that may cause harmful effects to marine invertebrates. Expression of microsomal proteins can be changed by oil exposure, causing functional alterations in endoplasmic reticulum (ER). The aim of this study was to investigate changes in protein expression signatures in microsomes of oysterl Crassostrea brasiliana (=C.gasar) gill after exposure to 10% diesel-WAF for 24 and 72 h. Protein expression signatures of gills of oysters exposed to diesel-WAF were compared to those of unexposed oysters using two–dimensional electrophoresis (2-DE) to identify differentially expressed proteins. A total of 458 protein spots with molecular weights between 30–75 kDa were detected by 2-DE in six replicates of exposed oyster proteomes compared to unexposed ones. Fourteen differentially expressed proteins (six up-regulated and eight down-regulated) were identified. They are: proteins related to xenobiotic biotransformation (cytochrome P450 6 A, NADPH-cytochrome P450 reductase); cytoskeleton (α-tubulin, β-tubulin, gelsolin); processing and degradation of proteins pathways (thioredoxin domain-containing protein E3 ubiquitin-protein ligase MIB2); involved in the biosynthesis of glycolipids and glycoproteins (beta-1,3-galactosyltransferase 1); associated with stress responses (glutamate receptor 4 and 14-3-3 protein zeta, corticotropin-releasing factor-binding protein); plasmalogen biosynthesis (fatty acyl-CoA reductase 1), and sodium-and chloride-dependent glycine transporter 2 and glyoxylate reductase/hydroxypyruvate reductase. Different patterns of protein responses were observed between 24 and 72 h-exposed groups. Expression pattern of microsomal proteins provided a first insight on the potential diesel-WAF effects at protein level in microsomal fraction of oyster gills and indicated new potential biomarkers of exposure and effect. The present work can be a basis for future ecotoxicological studies in oysters aiming to elucidate the molecular mechanisms behind diesel-WAF toxicity and for environmental monitoring programs.

柴油燃料中的水分（柴油-WAF）是有机化合物的复杂混合物，可能对海洋无脊椎动物产生有害影响。接触油可以改变微粒体蛋白的表达，从而引起内质网（ER）的功能改变。这项研究的目的是调查牡蛎Crassostrea brasiliana（= C.gasar）微粒体中蛋白质表达特征的变化）暴露在10％柴油WAF中24和72小时后的g。使用二维电泳（2-DE）来比较暴露于柴油WAF的牡蛎g的蛋白质表达特征和未暴露的牡蛎的蛋白质表达特征，以鉴定差异表达的蛋白质。与未暴露的牡蛎蛋白质组相比，在暴露的牡蛎蛋白质组的六个重复样本中，通过2-DE检测到总共458个分子量在30–75 kDa之间的蛋白质斑点。鉴定了十四种差异表达的蛋白质（六个上调和八个下调）。它们是：与异种生物转化相关的蛋白质（细胞色素P450 6 A，NADPH-细胞色素P450还原酶）；细胞骨架（α-微管蛋白，β-微管蛋白，凝溶胶蛋白）；蛋白质途径的加工和降解（含硫氧还蛋白域的蛋白质E3泛素蛋白质连接酶MIB2）；参与糖脂和糖蛋白（β-1,3-半乳糖基转移酶1）的生物合成；与应激反应有关（谷氨酸受体4和14-3-3蛋白ζ，促肾上腺皮质激素释放因子结合蛋白）；缩醛缩醛生物合成（脂肪酰辅酶A还原酶1），依赖钠和氯的甘氨酸转运蛋白2和乙醛酸还原酶/羟基丙酮酸还原酶。在24和72 h暴露组之间观察到不同的蛋白质反应模式。微粒体蛋白的表达模式为牡蛎g微粒体级分中蛋白质水平的潜在柴油WAF效应提供了首次见识，并指出了暴露和效应的新潜在生物标志物。