Abstract: Recently, people have paid more and more attention to the safety of aquatic products, high quality animal protein and healthy fat sources. Marine invertebrates are not only  good source of food protein, but also are  major source of polyunsaturated fatty acids (PUFA). The previous studies had shown that almost all PUFAs were originated from primary producers in aquatic ecosystems. PUFAs biosynthesized by microalgae in the ocean were caught by organisms at higher trophic levels of food chain for producing new PUFA through biotransformation or modification. A large number of studies on the pathways of PUFA biosynthesis and metabolism were reported in primary producers and vertebrates, however, little was known about PUFA biosynthesis and metabolism in  invertebrates. Therefore, this paper summarized the progress on PUFA biosynthesis and metabolism, as well as involved key enzymes and genes in five marine invertebrates (sponges, cnidarians, molluscs, crustaceans, and echinoderms), which provided valuable reference for understanding the synthetic metabolism and regulatory mechanism of PUFA in invertebrates.

Key words: marine invertebrate, polyunsaturated fatty acid, pathways of biosynthesis and metabolism, regulatory mechanism

摘要： 近年来，人们对水产品质量安全、优质的动物蛋白以及脂肪来源的关注度越来越高。海洋无脊椎动物不仅是优质食物蛋白的重要来源，也是人体获取多不饱和脂肪酸（polyunsaturated fatty acids，PUFA）的主要食物来源。研究表明，几乎所有的PUFA都来自于水生生态系统中的初级生产者，海洋中主要初级生产者微藻生产出PUFA进入食物链后，较高营养级生物可通过生物转化或修饰产生新的PUFA。关于初级生产者和脊椎动物中PUFA合成代谢的研究较多，但位于两者之间无脊椎动物PUFA的生物合成代谢途径却知之甚少。因此，本文对五类海洋无脊椎动物（多孔动物、刺胞动物、软体动物、甲壳动物和棘皮动物）PUFA的合成代谢途径以及参与其过程中重要酶和关键基因的研究进展进行了总结，以期为更深入地理解海洋无脊椎动物PUFA的合成代谢与调控体系提供有价值的参考资料。

关键词: 海洋无脊椎动物, 多不饱和脂肪酸, 合成代谢途径, 调节机理