海藻糖是一种重要的贮藏性碳水化合物。海藻糖酶是生物体内唯一能特异性的将海藻糖水解为两分子葡萄糖的酶，其活性高低调节着生长、发育、摄食、抗逆和滞育等生理过程中的能量平衡。玉足海参是我国南海海域的优势海参品种，在富、寡营养环境均广泛分布。本项目前期发现，海藻糖酶在玉足海参的食性转换和适应富、寡营养环境过程中，均可能起至关重要的作用。但到目前，在海洋动物尤其海参中，关于海藻糖酶功能和海藻糖代谢途径的研究尚缺。本项目在对玉足海参海藻糖酶基因克隆和表达模式研究的基础上，1）获得海藻糖酶活性重组蛋白，分析海藻糖酶在玉足海参主要藻类食物消化中的作用；2）利用显微注射siRNA、整体包埋原位杂交和饲喂干预法，探究海藻糖酶在玉足海参胚胎和幼体发育、稚参和幼参生长及成参（雌参）性腺发育过程中所起的作用。本研究旨在阐明海藻糖酶在玉足海参生长发育中的功能，为解释玉足海参在不同营养海洋环境的广泛适应机制奠定基础。

Trehalose is an important storage carbohydrate, and it could be exclusively hydrolyzed by trehalase. Trehalase can regulate energy metabolism in various physiological processes, such as growth, development, feeding, stress resistance and diapause. Holothuria leucospilota is the dominant sea cucumber species of the South China Sea, and it distributes widely across the rich and poor nutrient sea areas. In the preliminary research of this project, we found the evidences that trehalase may play a vital role in the processes of feeding habit conversion and adaptation to rich and poor nutrient environments. To date, studies regarding the functions of trehalase and metabolism pathways of trehalose are still limited in marine animals, especially in sea cucumbers. Based on our previous study on cDNA cloning and expression patterns of the H. leucospilota trehalase, the current project will be performed on two parts: 1) Obtain the active recombinant protein of H. leucospilota trehalase, and analysis its roles in the digestion of the major food algae of sea cucumber; 2) By usage of microinjection of siRNA, whole-mount in situ hybridization and feeding intervention, to explore the roles of trehalase in embryonic and larval development, juvenile and young adult growth, and gonadal development of adult. The aim of this study was to clarify the function of trehalase in H. leucospilota during its growth and development, and this may be benefit to the explaining the response and adaption of H. leucospilota in different nutrient environments.