德宏奶水牛乳腺组织miR-21-5p基因及其脂类代谢靶基因表达研究

Study on expression of miR-21-5p and targeted lipid metabolism genes in mammary tissues of Dehong dairy buffalo

试验旨在探究德宏奶水牛乳腺组织miR-21-5p基因及其靶基因的表达规律。选取饲养条件相同、同一胎次、年龄相近、处于泌乳中期的健康德宏奶水牛,分为高乳脂率组(H组)、中乳脂率组(M组)和低乳脂率组(L组)。每组选取3头奶水牛,屠宰后采集乳腺组织,提取总RNA。采用生物信息学方法预测miR-21-5p的靶基因。利用荧光定量PCR技术检测miR-21-5p及其靶基因的表达水平,并与课题组前期测定的乳脂率进行相关性分析。结果显示,miR-21-5p的靶基因可能为AGPAT6和GPAM。L组德宏奶水牛乳腺组织中miR-21-5p的表达水平高于M组和H组(P<0.01)。相关性分析结果显示,miR-21-5p与靶基因AGPAT6的表达水平呈极显著负相关(P<0.01),与靶基因GPAM的表达水平呈显著负相关(P<0.05),德宏奶水牛乳腺组织miR-21-5p表达量与乳脂率呈显著负相关(P<0.05),靶基因AGPAT6和GPAM与乳脂率呈极显著正相关(P<0.01)。蛋白互作网络结果显示,AGPAT6和GPAM互作关系最强。研究表明,miR-21-5p可能通过负调控靶基因AGPAT6和GPAM的表达影响乳脂合成,进而影响乳脂率。

The aim of the experiment was to investigate the expression of the miR-21-5p gene and its target genes in the mammary tissues of Dehong dairy buffalo.The healthy Dehong dairy buffalo with the same feeding conditions,the same parity,similar age and middle lactation were divided into a high milk fat rate group(group H),a medium milk fat rate group(group M)and a low milk fat rate group(group L).Three dairy buffaloes were selected in each group,and breast tissues were collected after slaughter to extract total RNA.Bioinformatics methods were employed to predict the target genes of miR-21-5p.The expression levels of miR-21-5p and its target genes were quantified by fluorescence quantitative PCR,and correlation analysis was conducted with previously determined milk fat content.The results showed that the possible target genes of miR-21-5p were AGPAT6 and GPAM.The expression level of miR-21-5p in mammary tissue of Dehong daily buffalo in the group L was extremely higher than that in the group M and group H(P<0.01).The results of the correlation analysis showed that the expression level of miR-21-5p was extremely and negatively correlated with the target gene AGPAT6(P<0.01),and significantly and negatively correlated with the expression level of the target gene GPAM(P<0.05).In the mammary tissue of Dehong dairy buffalo,the expression level of miR-21-5p was significantly and negatively correlated with the milk fat percentage(P<0.05),while the target genes AGPAT6 and GPAM were extremely and positively correlated with the milk fat percentage(P<0.01).The results of the protein interaction network showed that the interaction between AGPAT6 and GPAM was the strongest.The results indicate that miR-21-5p may influence milk fat synthesis by negatively regulating the expression of the target genes AGPAT6 and GPAM,and consequently influencing the milk fat percentage.