| 摘要: |
| 【目的】从表观遗传层面解析湖羊与乌珠穆沁羊两品种蒙古系绵羊尾脂沉积差异的分子机制，为绵羊肉质改良及品种选育提供理论依据 。【方 法】以（12±1）月龄健康母羊为研究对象，其中湖羊（H组）来源于甘肃省兰州市临夏县桥寺乡，乌珠穆沁羊（W 组）来源于内蒙古自治区锡林郭勒盟白音锡勒牧场，每组采集颈部新鲜血液样本，经液氮速冻保存；采用全基因组亚硫酸氢盐测序（WGBS）技术对样本进行分析 ，最后采用甲基化特异性PCR（MSP）技术，对筛选出的ITSN1、NCEH1 和CRTC3等关键基因的甲基化差异进行验证。【结果】测序数据质量优异，其中Q20、Q30均值分别为98.25%和95.01%，唯一比对率>83%，lambda DNA转化率>99.2%；CpG位点甲基化水平显著高于CHG和CHH，符合哺乳动物甲基化特征。共鉴定出大量差异甲基化区域（DMRs），其中CpG类型DMRs数量差异显著，且主要分布于远端基因间区（64.97%）和内含子区域（30.84%）。DMR关联基因富集于脂质代谢、细胞黏附及信号转导相关通路，如细胞外基质-受体相互作用（ECM-receptor interaction）、黏着斑（focal adhesion）。 PPI网络分析筛选出脂质分解代谢核心基因，包括磷脂酶家族基因（PLCH1、PLCE1、PLCG2、PLCB4和PLCL2）、信号转导相关基因（ITSN2和ITSN1）、代谢酶类基因（PAFAH1B1）、受体蛋白基因（LRP5）及信号通路调控基因（FRZB）等核心调控基因。MSP验证证实ITSN1、NCEH1和CRTC3基因的甲基化差异与测序结果一致。【结论】揭示了两品种蒙古系绵羊尾部脂肪沉积差异的表观遗传特征，结果可用于绵羊肉质改良及品种选育。 |
| 关键词: 蒙古系绵羊 脂肪沉积 全基因组亚硫酸氢盐测序 甲基化特异性PCR DNA甲基化 表观遗传调控 |
| DOI：10. 13207/j. jnwafu. 2026. 10. 001 |
| 分类号: |
| 基金项目:国家自然科学基金项目（3246200236）；甘肃省高校青年博士支持项目（2025QB-047） |
|
| Analysis of tail fat deposition differences in Mongolian sheep based on whole genome DNA methylation |
|
XU Yu, YANG Yang, ZHANG Yue, WEI Yingshi, NIU Ruilai, HOU Qianruo, ZHU Caiye
|
|
College of Animal Science and Technology，Gansu Agricultural University，Lanzhou，Gansu 730070，China
|
| Abstract: |
| 【ObjectiveThis research aims to analyze the molecular mechanism of tail fat deposition difference between Hu sheep and Ujimqin sheep from an epigenetic perspective，to provide a theoretical basis for sheep meat quality improvement and breed selection.【Method】Healthy ewes aged（12±1）months were selected as the research subjects，including Hu sheep（H group）sourced from Qiaosi Township，Linxia County，Lanzhou City，Gansu Province，and Ujimqin sheep （W group） sourced from Baiyin Xile Ranch，Xilingol League，Inner Mongolia Autonomous Region. Fresh blood samples were collected from the neck of the sheep in each group and rapidly frozen in liquid nitrogen for storage. The samples were analyzed using whole genome bisulfite sequencing（WGBS）technology. And methylation specific PCR（MSP）technology was used to verify the methylation differences of key genes selected including ITSN1，NCEH1，and CRTC3.【Result】The sequencing data showed high quality，with a mean value of Q20 and Q30 being 98.25% and 95.01%，respectively，a unique alignment rate>83%，and lambda DNA conversion rate>99.2%. The methylation level of CpG sites was significantly higher than those of CHG and CHH，which was consistent with mammalian methylation characteristics. A large number of differentially methylated regions（DMRs）were identified，among which CpG-type DMRs showed significant differences in quantity and were mainly distributed in the distal intergenic region（64.97%）and intronic region（30.84%）.DMR-related genes were enriched in pathways related to lipid metabolism，cell adhesion，and signal transduction，including extracellular matrix receptor interaction（ECM receptor interaction）and focal adhesion. PPI network analysis identified core regulatory genes for lipid breakdown metabolism，including phospholipase family genes（PLCH1，PLCE1，PLCG2，PLCB4，and PLCL2），genes related to signal transduction（ITSN2 and ITSN1），metabolic enzyme genes（PAFAH1B1），receptor protein genes（LRP5），and signal pathway regulatory genes（FRZB）.MSP validation confirmed that the methylation differences of ITSN1，NCEH1，and CRTC3 genes were consistent with the sequencing results.【Conclusion】The epigenetic characteristics of the differences in tail fat deposition between two breeds were revealed，which can be used for sheep meat quality improvement and variety breeding. |
| Key words: Mongolian sheep fat deposition whole genome bisulfite sequencing methylation specific PCR DNA methylation epigenetic regulation |
