毛翅目昆虫石蚕具有在激流中吐丝结网的习性，但目前对于其丝蛋白在水中的纤维化机制尚不明确，因而限制了石蚕丝这一特殊生物材料的开发利用。前期的研究中，我们发现石蚕的丝腺腔中央另隐藏有一条充满丝蛋白的芯管，使之呈现出独特的双腔结构，而且证实芯管具有定期更新脱落的“异常”特性。推测石蚕这种巧妙地双腔结构与其水中成丝密切相关，可为丝蛋白在“简短”的丝腺内完成纤维化提供最大的时间保障。本项目将（1）研究石蚕丝腺内腔即芯管内丝蛋白向前流动过程中纤维化程度的动态变化，并分析外腔相应区段内影响其纤维化的因素，探究内外双腔协同作用对石蚕丝蛋白成纤的影响；（2）解析芯管的蛋白组成，并通过分析芯管形成过程中的差异表达基因及其参与的信号通路，探究调控芯管形成的关键基因。最后建立基因敲除系统对筛选的关键基因进行验证，揭示芯管（双腔结构）形成的分子机理。研究结果将为阐明石蚕丝蛋白在水中的成丝机制提供一种新思路。

Trichopteran caddisflies evolve habits to spin silk in streams or rivers.The fibrillation mechanism of silk protein in water still remains to be unclear that restricts the use of this desirable bio-fibers.In our previous research, we found that there is a core tube filled with silk protein in the center of the silk gland of the caddisfly,which makes the silk gland present a unique double-cavity structure, and we also found the core tube has a periodic update feature.It is speculated that the double-cavity structure provides time and space guarantee for the completion of fibrosis before the caddisfly silk protein is excreted and encounters water, that is the wisdom of the caddisfly spinning in water.This proposal tends to study the dynamic changes in the degree of fibrosis of the silk protein during forward flowing in the core tube, analyze the factors affecting the fibrosis in the corresponding section of the external cavityof the external cavity, and explore the effect of internal and external double-cavity synergy on the silk fibroin formation.It will also be to examine the major protein component of the interior tubes, the transcriptional changes across renewal periods, and the relevant signaling pathway. The key regulatory genes in the formation of interior tubes will be mined and validated by gene knock-out strategy.This study is expected to provide a unique silk gland model for studying the relationship between organism structure and function.