The Role Of LncRNA And MiRNA In Dairy Milk Quality Regulation

The role and function of non-codingRNA in organ development and tissue cells are concerned increasingly by biological researchers.It has been found in previous studies that miRNAs,as a small molecule non-codingRNA,have been shown to be important in many life activities.MiRNAs have also played a key role in the development and progression of breast cancer.Studies in rodent and ruminant lactation also show that miRNAs can regulate lactation through multiple key genes.LncRNA is a non-codingRNA in the length of more than 200 bases,was found early but has been considered to be genomic transcription produced by the function of the byproducts.Recent studies have found that one of lncRNAs XISTs can inactivate X staining.The function of lncRNA can also regulate the transcription of the corresponding gene at the gene level by cis or trans.On the other hand can also form miRNA molecular sponge through the adsorption of miRNAs and thus affect the stability of the corresponding mRNA.In this study,mammary gland(high quality,low quality and dry emulsion)of different quality Holstein dairy cows were used as experimental materials,and high-throughput sequencing techniques were used to establish long-chain non-codingRNA expression libraries and smallRNA Expression of library,and then identify lncRNA and miRNA which regulate lactation quality of dairy cow,and the use of bioinformatics technology to establish network of lncRNA,miRNA,mRNA regulation of milk quality.The main findings are as follows:(1)There were 53 different lncRNAs in the high-quality group and the low-quality group,27 were up-regulated in the high-quality group and 26 in the low-quality group.(2)Differences between high-quality and dry-late expression miRNA sets and low-quality groups and dry-milk differential expression miRNA set of the intersection of miRNAs 25 through our analysis results show that these miRNAs are likely to play in the dairy cow development process mi R-138,mi R-296-3p,mi R-20 b,mi R-106 a,mi R-135 a,mi R-503-5p,mi R-433,mi R-543 and mi R-370.Functional analysis showed that they could be involved in the proliferation of mammary epithelial cells,the development of breast ducts and acinar through target genes,and therefore worthy of further study.(3)We analyzed the miRNA and mRNA analysis between the high quality group and the low quality group,and we obtained the negative control target relationship between miRNA and mRNA.Functional analysis showed that 38 miRNAs such as mi R-214,mi R-154 b,mi R-9-5p and mi R-2888 had a moderating effect on milk quality.We constructed a simplified network of protein and lipid metabolism by combining the 253 negative regulatory target genes of these miRNAs.The results showed that KDR(mi R-424-5p and mi R-450b),IGF2(mi R-409,mi R-214,mi R-424-5p and mi R-154b),TGFB3(bta-mi R-2888),SREBF1(bta-mi R-154b),PFKFB3(mi R-214 and mi RBta-mi R-2888)and PCK2(bta-mi R-382),which can be regulated by the corresponding miRNAs.(4)Through the combination analysis of miRNA,mRNA and lncRNA between high-quality group and low-quality group,we constructed the ceRNA relationship network.Further analysis showed that these lncRNAs could affect gene expression through the lncRNA-miRNA-mRNA relationship.(5)Some miRNAs,mRNAs and lncRNAs were verified by fluorescence quantitative PCR.The results were consistent with the sequencing results by analyzing the data of these genes.Therefore,the accuracy of the sequencing results was determined.By double luciferase experiments we identified the two miRNAs and the corresponding target regulatory analysis of the target regulatory relationship,which also confirmed the stability of the network we constructed the network.