Zhang Xiaolan, Shi Bingang, Zhao Zhidong, Deng Yunqi, Zhou Xuelan, Hu Jiang
College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China.
Int J Mol Sci. 2025 May 11;26(10):4601. doi: 10.3390/ijms26104601.
Differences in skin and hair phenotypes between the scapular and ventral regions of yaks (Bos grunniens) are obvious and become more prominent with age. However, the genetic mechanism that causes differences in yak skin at different ages has not been reported. In this study, we investigated the transcriptomic profile of yak skin across different ages (0.5 years, 2.5 years, and 4.5 years) and body sites (scapular and ventral regions). Differential gene expression analysis was initially conducted to explore the transcriptomic differences in skin at different ages and different body sites. Subsequently, weighted gene co-expression network analysis (WGCNA) was employed to analyze the transcriptomic data comprehensively. The results showed that, among all comparison groups, the Y2.5_S vs. Y2.5_V group (regional comparison) exhibited the highest number of DEGs, with 491 genes (179 upregulated and 312 downregulated), followed by the Y2.5_V vs. Y0.5_V group (age comparison), which had 370 DEGs (103 upregulated and 267 downregulated). DEGs such as , , , and were found in all comparison groups of different ages, and multiple members of the HOX gene family including , , , , and were differentially expressed in comparison groups at different sites. Functional enrichment analysis showed that there were more obvious differences in immune function between different ages of skin and more obvious differences in endocrine function between different parts of skin. WGCNA revealed that genes related with immunity such as , , and were the core genes of the co-expression module associated with the scapula region, and multiple genes related to hair follicle development such as , , , , and were found to be the hub genes of the co-expression module associated with the ventral region. Overall, our study provides valuable insights into the transcriptomic complexity of yak skin across different ages and body sites. The differential gene expression patterns and co-expression network modules identified in this study lay the foundation for further research on skin biology and adaptation mechanisms in yaks.
牦牛（Bos grunniens）肩胛部和腹部皮肤及毛发表型的差异明显，且随年龄增长愈发显著。然而，导致牦牛不同年龄段皮肤差异的遗传机制尚未见报道。在本研究中，我们调查了牦牛不同年龄（0.5岁、2.5岁和4.5岁）和身体部位（肩胛部和腹部）皮肤的转录组概况。最初进行差异基因表达分析以探究不同年龄和不同身体部位皮肤的转录组差异。随后，采用加权基因共表达网络分析（WGCNA）对转录组数据进行综合分析。结果显示，在所有比较组中，Y2.5_S vs. Y2.5_V组（区域比较）的差异表达基因数量最多，有491个基因（179个上调和312个下调），其次是Y2.5_V vs. Y0.5_V组（年龄比较），有370个差异表达基因（103个上调和267个下调）。在不同年龄的所有比较组中均发现了如 、 、 和 等差异表达基因，并且包括 、 、 、 和 在内的HOX基因家族的多个成员在不同部位的比较组中差异表达。功能富集分析表明，不同年龄的皮肤在免疫功能方面存在更明显的差异，而皮肤不同部位在内分泌功能方面存在更明显的差异。WGCNA显示，与免疫相关的基因如 、 和 是与肩胛部区域相关的共表达模块的核心基因，并且发现多个与毛囊发育相关的基因如 、 、 、 和 是与腹部区域相关的共表达模块的枢纽基因。总体而言，我们的研究为牦牛不同年龄和身体部位皮肤的转录组复杂性提供了有价值的见解。本研究中鉴定出的差异基因表达模式和共表达网络模块为进一步研究牦牛皮肤生物学和适应机制奠定了基础。
