College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, P.R. China.
College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, P.R. China; Anhui Province Key Laboratory of Local Livestock and Poultry Genetic Resource Conservation and Bio-breeding, Anhui Agricultural University, Hefei 230036, China.
Poult Sci. 2020 May;99(5):2775-2784. doi: 10.1016/j.psj.2019.12.056. Epub 2020 Mar 11.
Egg yolk is an important source of nutrients for embryo development. In this study, the egg yolk protein composition at 0, 10, and 18 D of incubation was analyzed by 2-dimensional gel electrophoresis (2-DE) combined with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry. A significant difference in the abundance of 42 protein spots representing 12 proteins were identified (P < 0.05). The 2-DE gel image analysis exhibited that the molecular weight (MW) of 29 protein spots was lower than their theoretical value, in which 14 vitellogenin (VTG) fragments were lower than the theoretical value. There were 13 protein spots showed a higher MW including 5 ovotransferrins with MW of 87.2 kDa. The gene ontology enrichment analysis suggested that biological process of the differentially expressed proteins were mainly involved in lipid transport and lipid localization at 10 and 18 D of incubation. The molecular function of the differentially expressed proteins was involved in nutrient reservoir activity, lipid transporter activity, and antigen binding at 10 D of incubation. At 18 D of incubation, the differentially expressed proteins mainly participated in nutrient reservoir activity and substrate-specific transporter activity. The high abundance of VTGs at 10 D of incubation might participate in lipid localization and lipid transportation to facilitate the yolk nutrient transport to embryo. The low expression of ovotransferrins at 10 D of incubation indicated the chondrogenesis of embryo.
蛋黄是胚胎发育的重要营养来源。在这项研究中，通过二维凝胶电泳（2-DE）结合基质辅助激光解吸/电离飞行时间串联质谱分析了孵化 0、10 和 18 天的蛋黄蛋白组成。鉴定出 42 个蛋白质斑点的丰度存在显著差异，代表 12 种蛋白质（P < 0.05）。2-DE 凝胶图像分析表明，29 个蛋白质斑点的分子量（MW）低于其理论值，其中 14 个卵黄蛋白原（VTG）片段低于理论值。有 13 个蛋白质斑点表现出更高的 MW，包括 5 种 MW 为 87.2 kDa 的卵转铁蛋白。基因本体富集分析表明，差异表达蛋白的生物学过程主要涉及孵化 10 和 18 天时的脂质转运和脂质定位。差异表达蛋白的分子功能涉及营养库活性、脂质转运活性和抗原结合在孵化 10 天。在孵化 18 天时，差异表达蛋白主要参与营养库活性和底物特异性转运体活性。孵化 10 天时 VTGs 的高丰度可能参与脂质定位和脂质转运，以促进蛋黄营养向胚胎的转运。孵化 10 天时卵转铁蛋白的低表达表明胚胎的软骨形成。
