孵化温度影响鸭胚胎骨骼肌发育的分子网络构建与调控途径研究

Previous studies have shown that an animal's embryonic muscle development as well as the adult phenotypes are influenced by various environmental conditions. These traits could potentially be used to enhance the efficiency of livestock meat production. There is currently no information underlying these mechanisms however. The hatching temperature under specific conditions, could potentially act as a pivotal factor in avian embryo development, in order to influence embryonic skeletal muscle development. It was hypothesized that the molecular networks and cellular regulatory pathways that influence such phenotypes could play key roles in these processes. The objective of this study is to build an animal model to explore how hatching temperature influences the duck's embryonic skeletal muscle development. Transcriptome sequencing technology will be used for the differential expression genes during duck embryonic skeletal muscle development. Bioinformatics methodology and the molecular regulatory network will then analyze the data in order to determine the hatching temperature in which the duck embryonic skeletal muscle development will be built. Based on the results of molecular networks, the regulated pathways involving myoblast proliferation, satellite cell activation and proliferation, muscle protein metabolism and muscle fiber type differentiation will be confirmed by immunology, protein and nucleotide quantification techniques. This work will reveal the mechanism by which hatching temperature has on embryonic skeletal muscle development. It will also provide new clues and knowledge to study the effects of environmental conditions on an animal's embryonic skeletal muscle development.

已有研究表明，很多外源环境可以影响动物胚胎骨骼肌发育及后天生长表型，被作为改善畜禽后天生产性能的新途径，但相关调控机制研究还很匮乏。孵化温度是维持禽类胚胎正常发育外源环境之一，适当改变能引起禽类胚胎骨骼肌发育不同表型指标的改变，推测肌细胞内分子网络和不同细胞过程起了主要作用。本项目将建立孵化温度影响鸭胚胎骨骼肌发育的研究模型，运用转录组测序技术筛选鸭胚胎肌肉差异表达基因，结合生物信息分析构建分子网络，给出孵化温度影响鸭胚胎骨骼肌发育的分子基础；在分子网络分析基础上，运用免疫组化和核酸蛋白丰度检测技术，进一步分析孵化温度对成肌细胞增殖、卫星细胞激活、肌蛋白代谢，以及肌纤维类型分化的影响，揭示孵化温度调控鸭胚骨骼肌发育的途径，将为孵化温度影响鸭胚胎骨骼肌发育的机制研究奠定基础，对外源环境影响动物胚胎骨骼肌发育调控机理研究提供思考和借鉴。

动物胚胎发育状态与后天生产性能相关，通过孵化温度干预禽类胚胎发育，被作为改善禽类生产性能的新途径之一。本研究构建了孵化温度影响鸭胚胎骨骼肌发育模型，发现孵化温度改变对胚胎及出壳后骨骼肌发育有明显影响。构建了孵化温度影响鸭胚胎骨骼肌发育的分子网络，发现孵化温度主要通过影响细胞蛋白质合成等过程，对鸭胚胎肌肉发育产生影响。其中，核糖体代谢过程、MAPK和TGFβ信号路径是孵化温度影响鸭胚骨骼肌发育的重要分子途径，而IGF-1、FST、AKIRIN2、Ccna1、MyoG、PPAR等可能是参与其中的关键基因。孵化温度对胚胎期成肌细胞、以及雏鸭出壳后卫星细胞活性有影响，可能间接影响到了骨骼肌发育。初步证据表明，孵化温度还可能通过影响骨骼肌DNA甲基化，影响到了部分与骨骼肌发育相关基因的表达，进而影响骨骼肌发育。经过系列研究发现，孵化温度对鸭胚骨骼肌发育影响的分子机制是非常复杂的过程，不仅涉及到决定骨骼肌发育的多方面因素，包括细胞增殖和分化、蛋白质合成代谢等，还与基因组DNA甲基化有关。本课题完成了既定研究内容和目标，相关研究内容在Poultry science、Journal of thermal biology、PLos One、Growth hormone & IGF-1 research、Bioscience reports、The international journal of biochemistry & cell biology、农业生物技术学报、畜牧兽医学报等杂志上发表论文11篇。