多环芳烃对双齿围沙蚕生殖毒性效应分子机制的研究

With the development of industry and urbanization, a large number of Polycyclic aromatic hydrocarbons (PAHs) accumulate in marine environment,which causes huge threat to the reproductive system in marine organisms.Some researchers have paid close attention to the reproductive toxicity of PAHs. At present researchs mainly focus on fishes and molluscs, and there is little information about reproductive effect of PAHs in marine polychaetes which play an important role in PAHs biotransformation in sediment. In this study the polychaete Perinereis aibuhitensis which is widely distributed in China is chosen as experimental animal. The changes of estrogen in different groups are analyzed. The potentially key genes in estrogen mediated-signal transduction pathway in P.aibuhitensis under PAHs exposure are screened,and the functions of these key genes are studied separately in the levels of gene and protein expression. The relationship among PAHs, estrogen content and expression of key genes are analyzed. Combined with histological observation on the germ cell in P. aibuhitensis under PAHs exposure, the effect of PAHs on P. aibuhitensis reproductive system are studied on different way. With the result of this study the molecular mechanism of the reproductive toxicity of PAHs in P. aibuhitensis will be illustrated which will give helpful insight for investigating the stress-related cellular response and for identifying potential biomarkers for environmental risk assessment.

随着海洋环境中多环芳烃PAHs污染的日益加剧，PAHs对海洋生物生殖危害作用日益凸显，PAHs对海洋生物的内分泌干扰机制已备受关注。目前PAHs对海洋生物生殖毒性的研究多集中于鱼类和贝类，而在沉积质PAHs转化和分解中起关键作用的海洋多毛类中，尚未发现相关方面的研究报道。本项目选取在我国广泛分布的双齿围沙蚕作为多毛类模式生物，分析PAHs暴露下沙蚕体内雌激素含量的变化规律，探讨雌激素受体介导通路主要调控基因的响应特征，明确PAHs-雌激素-调控基因表达的耦联关系；结合PAHs暴露下沙蚕生殖细胞发育分化特征的观察，从细胞、基因及蛋白等多个水平阐释PAHs对双齿围沙蚕的生殖毒性效应。该项目将丰富多毛类PAHs毒性效应的研究，并为利用多毛类进行海洋环境污染监测提供重要的理论依据。

随着海洋环境中多环芳烃（PAHs）对海洋生物生殖危害作用日益凸显，PAHs对海洋生物的内分泌干扰机制已备受关注。海洋多毛类由于其沉积食性及不易远距离迁徙等特性，极易有机污染物于体内，然而有关污染物对多毛类生殖毒性效应的报道甚少。本项目选取在我国广泛分布的双齿围沙蚕作为研究生物，以苯并芘作为暴露污染物，首先从组织学和生理学面探究了苯并芘是否对双齿围沙蚕具有生殖毒性效应。结果表明苯并芘诱导会引起沙蚕卵母细胞卵径增大，导致沙蚕体内雌激素含量升高，表明苯并芘亦属于环境雌激素，对沙蚕具有生殖毒性效应。在此基础上本研究深入到分子水平，筛选部分关键调控基因（VTG，ERR和G蛋白等），分析了苯并芘诱导前后沙蚕体内这些关键调控基因及蛋白的表达规律，结果表明苯并芘诱导会导致VTG基因及蛋白表达出现显著变化，苯并芘诱导还会引起沙蚕体内ERR、GnRHR、G蛋白及PKA等基因表达显著上升，可以推测苯并芘通过沙蚕体内雌激素核受体途径和G蛋白介导的非核受体途径同时对沙蚕产生生殖毒性效应。通过该项目的实施，建立了关键调控基因的实时定量PCR检测方法及蛋白的间接ELISA检测方法，为利用沙蚕进行海洋环境污染监测奠定一定的理论基础和技术支撑。