CSDC2调控绒山羊次级毛囊周期性生长的分子机制

The growth of cashmere is a complex physiological process exhibiting a seasonal pattern arising from photoperiodchange. The yield of cashmere is related withduration of the secondary follicle anagen for Cashmere goat. The transcription factor Csdc2 plays an important role in regulating hair follicle cycle. Here we will apply the techniques of Chip-seq, RNA interference, cell proliferation and Western blot for secondary hair follicle dermal papilla cells of Cashmere goats, (1) to find the target genes of Csdc2 to reveal the regulatory network; (2) to analyze the proliferation and apoptosis ofcells after silencing Csdc2 to elucidate regulatory role of Csdc2 on the cashmere periodic growth of Cashmere goats; (3) to reveal the regulatory mode between Csdc2 and these key genes regulating the periodic growth of hair follicle, then to understand the molecular mechanism of Csdc2 on regulating the secondary hair follicle cycle of Cashmere goat. Overall, the study is helpful for understanding the mechanism of the periodic growth of secondary hairfollicles of Cashmere goats, which will laid a theoretical foundation for the promotion of shortphotoperiod increasing cashmere yield technology and the molecular breeding of Cashmere goat.

绒山羊绒毛周期性生长是一个复杂的生理过程，受光周期影响而具有很强的季节性，绒山羊绒产量与次级毛囊生长期的长短有关，挖掘影响次级毛囊周期性生长的关键基因并揭示其调控机理意义重大。本研究围绕绒山羊次级毛囊的周期性生长受转录因子Csdc2的调控这一科学问题，拟采用Chip-seq、RNA干扰、细胞增殖及Western blot等实验方法，以绒山羊绒毛生长旺盛期次级毛囊毛乳头细胞为研究材料，重点研究：1）确定转录因子Csdc2调控的靶基因1-2个，并构建其调控网络；2）分析Csdc2对绒山羊次级毛乳头细胞增殖和凋亡的影响，揭示Csdc2对绒山羊毛囊周期性生长的调控作用；3）探明Csdc2与调控毛囊周期性生长的关键基因间的调控模式，逐步解析Csdc2参与绒山羊次级毛囊周期性生长调控的分子机制。预期研究结果可为理解绒山羊绒毛周期性生长提供理论依据，为光控增绒技术的推广及绒山羊分子设计育种奠定理论基础。

绒山羊产业在我国畜牧业中占有重要地位，绒山羊绒毛生长具有周期性的特点，解析绒山羊毛囊周期性生长的生理和分子调控机制是科学提高产绒量关键。CSDC2（Cold-shock domain (CSD) containing C2）为我们前期鉴定到的与毛囊周期性生长调控相关的重要转录因子，本研究以体外分离的绒山羊次级毛囊组织、原代培养的毛乳头细胞及成纤维细胞为研究对象，利用绒山羊绒毛生长不同时期皮肤组织转录组数据、制备CSDC2抗体及联合Chip-seq技术、组织免疫组化分析、CSDC2体外干扰实验、褪黑激素体外处理等实验方法，成功构建绒山羊绒毛不同生长周期的加权基因共表达网络，并挖掘到毛囊周期性生长调控的核心基因，证明了转录因子CSDC2在绒毛周期性生长中的重要性，解析绒山羊不同生长周期皮肤组织中褪黑激素受体和催乳素受体的表达特点，新挖掘到VDR、FAT4、MAN1A、ROBO2、NOVA1和ZBTB20可作为CSDC2参与绒毛周期性生长调控过程中的重要靶基因，通过沉默CSDC2后成纤维细胞的增殖速率降低，且影响重要毛囊周期性生长信号通路关键基因的表达，揭示褪黑激素可介导转录因子CSDC2参与毛囊周期性生长的调控，以上研究结果为解析绒山羊季节性产绒的机理及分子设计育种实现绒毛生长期的调控来增加绒毛产量提供理论支撑。