蛋壳作为鸡蛋的重要组成部分具有周期性形成的规律。目前，关于蛋壳形成过程中的昼夜节律调控机制研究尚属空白。本项目组前期研究发现时钟基因在鸡输卵管子宫部节律性表达，这暗示着生物钟可能调控蛋壳形成。因此，本项目提出时钟基因通过发条机制调控离子和离子转运协同蛋白等节律性表达，促使蛋壳周期性形成的科学假设，筛选产蛋时间一致的鸡只，测定24h周期内血液激素含量及子宫部时钟基因的表达水平，分析昼夜节律信息传递到子宫部的内分泌路径；采集子宫部进行转录组测序，筛选时钟基因和蛋壳形成相关钟控制基因；使用ChIP-seq钓取时钟基因蛋白结合的钟控制基因；体外培养子宫部上皮细胞，使用双荧光素酶报告系统鉴定钟控制基因和时钟基因结合位点；人工启动时钟基因发条机制，检测子宫部上皮细胞中时钟和钟控制基因的表达情况。本项目尝试从生物钟这一独特角度解释蛋壳周期性形成的分子调控机制，为研究蛋壳形成机理提供了新思路。

There is an obvious rhythm of eggshell formation. Until now, there is no study on the controlling mechanism of circadian rhythms on the eggshell formation process. In previous study, we found there were clock genes had rhythmic expression patterns like the cosine curve in the uterus of the oviduct, which implied biological clock may control the eggshell formation. Thus, our team formulate a hypothesis that biological clock may control the expression rhythms of the eggshell-related ions and their transporters via clockwork. We plan to select the layers with close laying time to determine their hormone concentrations in serum, to make clear the endocrine pathway which passing the external rhythms into internal environment. We also want to obtain the clock genes and clock-controlled genes via RNA-seq and ChIP-seq. Culture the epithelial cells sampled at uterus to determine the combining sites between the clock genes and clock controlled genes via dual luciferase reporter system. Artificially start the clockwork of epithelial cells to test the expression pattern of clock genes and clock-controlled genes. Our team try to explain the molecular controlling mechanism of eggshell formation in a biological clock way, which may through a light on a new method to understand the eggshell formation.