砷是一种无处不在的环境有毒物质，全球性砷污染日益严重。本项目选取典型真核绿藻小球藻作为研究对象，通过砷暴露模拟实验，运用流式细胞术、高效液相色谱-电感耦合等离子体质谱分析、实时荧光定量PCR、原核表达技术等手段，分别从砷对小球藻的细胞凋亡影响、细胞对砷的富集、转化和挥发以及砷甲基化基因的克隆和功能分析等方面，分析砷暴露下小球藻的生理生化特性和关键功能基因的表达调控方式。深刻探讨小球藻砷代谢特征及其分子机制，阐明土水环境中真核绿藻与砷的生物地球化学循环的联系。研究结果可丰富生物化学和环境生物学的理论，为环境介质-污染物-真核藻类相互作用的深入研究开辟新的思路，在实践上可为藻类修复砷污染环境提供科学依据。

Arsenic is a pervasive and ubiquitous environmental toxin that has created numerous environmental problems around the world. To understand the physiological and biochemical characteristics and the regulations of the key functional gene expression in the typical eukaryotic green alga Chlorella vulgaris under arsenic exposure, in this study, the applicant will analyse cell apoptosis, intracellular arsenic biotransformation and identify arsenite methyltransferase gene by some technical means including flow cytometry, HPLC-ICP-MS, real-time PCR and prokaryotic expression. All this work will elucidate the characterization of arsenic metabolism and molecular mechanism in the green alga. Moreover, it will be helpful to illustrate the connection between eukaryotic alga and arsenic biogeochemistry cycle. These results will enrich the theory on biochemistry and environmental biology; open up a new way for environment medium-pollutant-eukaryotic alga interaction research; supply some scientific bases for bioremediation of arsenic pollution by alga.