微藻产油是最具潜力的生物柴油生产途径之一， 研究微藻脂肪酸运输机制对获得高产油微藻具有重要意义。 脂肪酸跨叶绿体膜输出的过程是油脂合成的必需路径，但迄今为止，脂肪酸跨膜输出机制仍有待揭示。申请人此前的研究表明：植物拟南芥（A. thaliana）细胞中，新型的膜蛋白家族FAX与脂肪酸跨膜输出密切相关（尚未发表）。我们在单细胞绿藻-莱茵衣藻(C.reinhardtii)中，发现了和FAX唯一同源的蛋白，命名为Cr-FAX。初步实验表明该蛋白与脂类代谢有关。 本课题以此为出发点，拟通过亚细胞定位、 Cr-FAX突变体的表型、脂类和转录组分析，研究Cr-FAX在脂肪酸跨叶绿体膜运输中的作用。 并在拟南芥FAX1基因敲除突变体At-fax1中及脂肪酸运输缺陷型酵母fat1中进行Cr-FAX的脂肪酸运输功能验证。最终为阐明产油微藻中脂肪酸运输机制提供理论基础，为获得高产油的基因工程藻株提供理论依据。

Oleaginous microalgae is one of the most potential way for biodiesel industry. Fatty acid (FA) synthesis occurs in chloroplasts and thus export for subsequent lipid assembly is required. Yet, the mechanism of this transport remains enigmatic. The former research by applicant shows that, a novel membrane protein family FAX may be involved in mediating fatty acid export from plastids (unpublished). Interestingly, in unicellular green algae-Chlamydomonas reinhardtii, the unique ortholog of FAX is exist, named Cr-FAX. And former data imply Cr-FAX is involved in lipid biosynthesis. In this proposal, the phenotype of Cr-FAX mutants are firstly screened. With further lipidomic, subcellular localization and transcriptomic analysis results, Cr-FAX might be argued whether involving in chloroplast fatty acid export. Furthermore, to illuminate the key transporter function of Cr-FAX, Cr-FAX will be transformed into Arabidopsis at-fax knockout mutant and also fat1 yeast mutant, who lost fatty acid transport function. The characterization of Cr-FAX will not only be significant for unknown fatty acid export process in algae, but also represent a powerful tool to increase lipid/biofuel production in green algae.