Lipopolysaccharide binding protein (LBP) is a key factor in the recognition of lipopolysaccharide (LPS) and the initiation of immune response, thus regulating the body's resistance to pathogenic infection. To investigate the tissue-specific expression characteristics of the LBP gene and its transcriptional regulation in pigs, we detected LBP expression in different tissues of 35-day-old Meishan weaned piglets, determined LBP core promoter region using bioinformatics prediction combined with dual luciferase activity assay, and finally detected methylation levels by pyrosequencing. The results showed that LBP expression in the liver tissue was significantly higher (P>0.01) than that in other tissues, followed by the intestinal tissues. The core promoter region of LBP was located at –500–(–206) bp (chr.17: g.46837534–g.46837828), containing three CpG sites (CpG1, CpG2 and CpG3). Of the three CpG sites, CpG2 and CpG3 were variously methylated (P>0.01) in different tissues. Moreover, LBP mRNA levels were negatively correlated (P>0.01) with methylation levels of the CpG2 and CpG3 sites in the YY1 transcription factor binding sequence. It is speculated that the methylation of CpG2 and CpG3 sites might inhibit YY1 binding to the promoter sequences, thereby regulating the tissue-specific expression of LBP. This study demonstrated the distinct patterns of LBP expression and promoter methylation in the tissues of Meishan pigs and indicated the potential roles of DNA methylation in regulating LBP expression, which may contribute to further investigations on pig LBP gene expression and function.

脂多糖结合蛋白（LBP）是识别脂多糖（LPS）和启动免疫反应的关键因素，从而调节机体对病原体感染的抵抗力。为了研究LBP基因在猪中的组织特异性表达特征及其转录调控，我们检测了35日龄眉山断奶仔猪不同组织中的LBP表达，并通过生物信息学预测与双重荧光素酶活性测定相结合确定了LBP核心启动子区。 ，最后通过焦磷酸测序检测甲基化水平。结果表明，肝脏组织中LBP表达明显升高（P> 0.01），比其他组织高，其次是肠道组织。LBP的核心启动子区域位于–500 –（– 206）bp（chr.17：g.46837534–g.46837828），包含三个CpG位点（CpG1，CpG2和CpG3）。在这三个CpG位点中，CpG2和CpG3在不同组织中被不同程度地甲基化（P > 0.01）。此外，LBP mRNA水平与YY1转录因子结合序列中CpG2和CpG3位点的甲基化水平呈负相关（P > 0.01）。推测CpG2和CpG3位点的甲基化可能抑制YY1与启动子序列的结合，从而调节LBP的组织特异性表达。这项研究证明了LBP的独特模式在眉山猪组织中的表达和启动子甲基化，表明DNA甲基化在调节LBP表达中的潜在作用，这可能有助于进一步研究猪LBP基因的表达和功能。