生物节律蛋白Period 2调控瘤胃上皮挥发性脂肪酸吸收的机制

反刍动物瘤胃对其主要能量利用形式挥发性脂肪酸（VFA）的吸收能力与饲料利用效率、生产潜力发挥和机体健康密切相关。瘤胃上皮有生物节律蛋白Period 2配体PPARs的表达，其中PPARα的活化可提高瘤胃上皮对VFA的吸收能力，但Period 2蛋白是否对瘤胃上皮VFA的吸收也有调控作用以及其调控机制尚不得而知。为此，本课题拟进行Period 2蛋白调控瘤胃上皮VFA吸收机制的研究。拟首先采用不同VFAs进行瘤胃上皮细胞体外培养，以明确Period 2蛋白与VFA吸收的关系；进而沉默或过表达Period 2基因，以研究其是否通过影响瘤胃上皮细胞的增殖活性、PPARs介导的生物钟节律调控通径、表观遗传特征等机制来调控VFA吸收的；而后再利用瘤胃灌注技术，研究Period 2蛋白与瘤胃主要VFAs吸收速率的调控关系，以期为今后研究环境因子等因素调控瘤胃上皮VFA吸收的技术与机制提供一些参考资料。

The rumen absorbability on the volatile fatty acids (VFA), the main energy forms of ruminants, is closely associated with the feed utilization, production performance and body health. Studies show the expression of PPARs, ligands of period 2, in remun epithelium; and the activation of PPARα among PPARs results in the increase of rumen VFA absorbability. However, it is not very clear whether Period 2 has regulating function on rumen VFA absorption and how it works. For this purpose, this project concentrates on clarifying the regulatory mechanism of Period 2 on VFA absorption in rumen epithelium. Firstly, rumen epithelial cells are cultured with different types of VFAs to verify the relationship between Period 2 protein and VFA absorption. Secondly, by silencing or overexpressing Period 2 gene in rumen epithelial cells, investigates whether Period 2 regulates VFA absorption though manipulating the cell proliferability, circadian rhythm pathway mediated by PPARs and epigenetic modifications etc. Thirdly, the rumen infusing technique is introduced to explore the control relationship of Period 2 protein on the absorption rates of main types of VFAs in rumen. This project hopes to provide some basic references for future researches on the control mechanism and technology of environmental factors on ruminal VFA absorption.