多氯联苯（PCBs）是12种优先控制持久性有机污染物（POPs）之一，也是典型的甲状腺干扰物（TDCs），可能会严重影响生物的生存、生长和繁衍。目前研究较多的是PCBs对鱼类的甲状腺干扰效应，主要集中于对THs的合成、转运和代谢的影响。但PCBs对软体动物特别是双壳贝类的甲状腺激素干扰效应还鲜见报道，其干扰途径和干扰作用靶点都有待研究。本项目结合我国近海PCBs污染现状，选择Aroclor 1254为代表，通过构建Aroclor 1254胁迫下文蛤（M. meretrix）消化盲囊组织动态差异基因表达谱，整体分析Aroclor 1254对文蛤的毒性效应；构建文蛤甲状腺激素受体（TRs）和甲状腺转运蛋白（TTR）的酵母重组系统，查找PCBs的干扰机制；探究Aroclor 1254对文蛤甲状腺激素干扰效应，为筛选出TDCs的海洋生态毒理评价提供新的思路。

Thyroid hormones (THs) have an important regulating effect on biological growth and reproduction. Thyroid hormone disrupting effects may seriously affect the biological survival, growth and reproduction of marine organisms. Polychlorinated biphenyls (PCBs) have been listed as one of the twelve persistent organic pollutants (POPs) under the Stockholm, which were also some of the most widely studied thyroid-disrupting chemicals (TDCs). Recently, more attention has been paid to the disturbance of thyroid system by PCBs in fish, which focused on the synthesis, transport and metabolism of THs. However, rarely been reported the disrupting effects on THs pathway of mollusks, especially bivalves. This study used commercialized PCBs mixtures, Aroclor 1254, to figure out the thyroid disruption effects of PCBs under environmental related concentration on M. meretrix, constructing the dynamic defense transcriptome responsive to the analysis of the toxic effect of Aroclor 1254; to probe its role in the synthesis of THs, and the expression levels of genes in synthesis, transport, metabolism and excretion processes. Constructing two recombinant yeast THs systems of TRs and TTR from M. meretrix aims to find out the disruption interaction sites of PCBs, to resolve the mechanism of Thyroid hormone disrupting effects PCBs-induced in clam M. meretrix. This study provides a preliminary basis and new idea for studying screening methods of ecotoxicology assessment of TDCs.