母鸡卵巢内细胞间互作对原始卵泡发生及其发育的调节作用

The formation of the primordial follicles and its subsequent development is the foundation of the poultry fertility. During these two critical physiological courses of follicular development, there are extensive cell proliferation and enormous intercellular interactions under precise regulation of various factors. This project adopts high throughput sequencing technology to screen the predominant positive and negative factors involved in regulating follicle formation and development. Based on functions of the single factors, we focus on their combined effects to clarify their overall functions in cell development. The studies including: ① selection of the key factors involved in germ cell and somatic cell interactions to regulate chicks primordial follicle formation; ② effects of the local cell interacting factors on chick primordial follicle formation; ③ regulation of the intra-follicular germ cell-somatic cell interacting factors on sustained development of the pullet growing follicles; ④ screening of the dominant genes in regulating follicle development by transcriptome sequencing in the growing follicles; ⑤ functions of the dominant genes in regulating follicle development. The results will help to clarify the functions of the intraovarian intercellular interactions on primordial follicle formation and rapid development of the growing follicles and also provide critical references for exploration of the measures of enhancing poultry laying performance.

原始卵泡的形成及其后续发育是母禽繁殖力的基础。在卵泡发育历程中这两个关键的生理环节存在大量的细胞增殖和多种细胞间的互作，这种互作受到多种因素的精确调节。本项目拟采用高通量测序技术筛选出调节卵泡发生和发育的关键性正向和负向因素，重点是在细胞间发挥关键调节作用的因子。在揭示其单个因子作用的基础上，着重阐明其联合作用，然后在细胞发育层面澄清其总体效应。内容包括：① 雏鸡原始卵泡形成过程中生殖细胞与体细胞间互作效应关键因素的筛选；② 局域性细胞互作因子对雏鸡原始卵泡形成的调节作用；③ 青年鸡卵泡内体细胞与卵母细胞间相互作用对生长卵泡持续发育的影响；④ 不同发育阶段生长卵泡转录组测序以分析调节卵泡发育的主导基因；⑤ 生长卵泡发育调节主导基因的作用及其机理的研究。研究结果有助于阐明母鸡卵巢内细胞间互作对原始卵泡形成及生长卵泡快速发育的调节作用及其机理，为家禽产蛋性能提升措施的研究提供重要的参考依据。

原始卵泡的形成及其后续发育是母禽繁殖力的基础。在卵泡持续发育或闭锁这两个关键生理环节中存在多种细胞间互作，这种互作又受到多种因素的精确调节，从而影响卵泡发育的命运。本项目采用高通量测序技术筛选出调节卵泡发育或闭锁的关键性正向和负向因素，并利用多种形态学和分子生物学技术研究细胞间互作因子的作用机理。所得结果包括：① 转录组分析阐明鸡生长和等级前卵泡发育的潜在调控机制，发现细胞外基质-受体互作、类固醇合成、吞噬体和血管生成等在卵泡发育中起主导作用。② 多种细胞间互作因子参与卵泡发育的调节，如FSH和SCF通过相互刺激作用以提高卵巢细胞增殖、抑制细胞凋亡而促进鸡卵泡的组装；局域性细胞因子LIF和bFGF通过AKT、ERK和Wnt/β-catenin信号通路刺激原始卵泡的激活；bFGF通过FGFR1-AKT信号通路促进卵泡膜细胞增殖和血管生成、下调卵泡颗粒细胞中VLDLR的表达，进而增强小白卵泡中卵黄沉积使卵泡得以快速发育；颗粒细胞分泌BMP4来维持等级前卵泡的发育。③ 研究了蛋鸡卵巢衰老机理及缓解措施，发现原花青素、番茄红素、二甲双胍和N-氨甲酰谷氨酸通过缓解衰老蛋鸡卵巢组织氧化应激等途径提升蛋鸡卵泡发育和产蛋量；④ 研究了卵泡闭锁及退化卵泡的功能，发现LIF可通过激活PI3K/AKT和Stat3信号通路抑制卵泡颗粒细胞的自噬性凋亡，进而缓解蛋鸡等级前卵泡的闭锁；排卵后卵泡通过PGE2-EP2信号途径促进蛋鸡等级前卵泡的生长。以上结果有助于阐明母鸡卵巢内细胞间互作对原始卵泡形成及生长卵泡快速发育的调节作用及其机理，为家禽产蛋性能提升措施的研究提供重要的参考依据。课题组完成了预定目标，在Frontier Cell Dev Biol、Oxid Med Cell Long、Theriogenology和Poult Sci等刊物上发表了21篇论文，其中IF5＞5者8篇。培养了16名研究生。