Screening Of MicroRNA Key Genes In Type 2 Diabetes Mellitus

Objective :In this study,we obtained micro RNA expression data from peripheral blood of type II diabetic patients by high-throughput sequencing,and constructed a weighted gene co-expression network of miRNAs in peripheral blood of type II diabetic patients.The gene modules and key node genes with co-expression relationships in the network were identified to predict the roles of miRNAs in the upstream and downstream of gene regulation.To provide a theoretical basis for the study of the development,diagnosis and treatment of type II diabetes.Methods :In this study,three new cases of type II diabetes mellitus in men aged 40-60 years were collected as a case group and three age-and sex-matched healthy physical examiners served as a control group.Three new patients with type II diabetes were first diagnosed and treated for type II diabetes at the Second Affiliated Hospital of Jilin University from August 2017 to June 2018,and three health check-ups were performed at the hospital in the same time period.Fasting venous blood and clinical data and relevant information were collected from six volunteers.High-throughput sequencing was performed using the Illumina Hiseq platform,following the PE150 strategy.The sequenced miRNAs were processed using a weighted gene co-expression network to obtain gene co-expression modules with co-expression relationships.Gene modules that were highly associated with type II diabetes were identified using the first principal component,the eigenvector gene measure module,in relation to type II diabetes.The key node genes in the co-expressed gene modules were identified quantitatively by both module identity and gene salience as the focus of the study.KEGG(Kyoto Encyclopedia of Genes and Genomes,KEGG)signalling pathway enrichment analysis of key node genes using the DAVID functional annotation tool to identify the biological function of the modules.protein-protein interaction(PPI)analysis of key node genes using String database to study proteins with a critical role in the process of type II diabetes.A comprehensive signalling pathway enrichment analysis combined with protein interaction network analysis was used to identify key node genes that play an important role in the development of type II diabetes.Result :1.1344 miRNA expression data were finally obtained by high-throughput sequencing of peripheral blood samples from 6 study subjects after quality control processing of the raw sequencing data.2.The weighted gene co-expression network identified a total of ten gene modules with co-expression relationships,namely Turquoise,Blue,Brown,Yellow,Green,Red,Black,Pink,Magenta,and Grey modules.Four modules highly associated with type II diabetes were identified by first principal component vector genes,namely Blue,Brown,Magenta,and Turquoise.A total of 59 key node genes in the modules defined by module identity and gene salience.3.KEGG signaling pathway enrichment analysis was performed on key node genes in four modules highly associated with type II diabetes,and the top 20 biological signaling pathways in the modules were selected according to rich factor ranking.Analysis of the biological signaling pathways shared by the four modules yielded Rap1 signaling,Lysosome,Fc gamma R-mediated phagocytosis and MAPK signaling pathways.4.The top three proteins in terms of connectivity,RPS27 A,UBC,and RAC1,were obtained by protein interaction network analysis of key node genes.5.Combining the protein interaction network results with the KEGG bio signaling pathway analysis,the biological signaling pathways involved in each of the three proteins were clarified,with RAC1 involved in the process of 25 of the signaling pathways and RPS27 A involved in the process of two of the signaling pathways.6.The miRNAs affecting these three proteins were obtained based on miRNA target gene prediction as miR-1271-5p,miR-130a-3p,miR-130b-3p and miR-574-3p.The type II diabetes miRNA database with number GSE21321 downloaded from GEO database was cross-validated and finally 69 miRNAs were obtained.Conclusion :1.In this study,four gene modules with co-expression relationships associated with type II diabetes were identified by weighted gene co-expression network analysis.2.A total of four miRNAs: miR-1271-5p,miR-130a-3p,miR-130b-3p,miR-574-3p and three key proteins: RPS27 A,UBC and RAC1 were screened by KEGG biosignaling pathway enrichment analysis and protein-protein interaction network binding analysis of key node genes in these four modules.3.Combined with biosignaling pathway enrichment analysis and protein-protein interaction network analysis,RAC1 and miR-574-3p were identified as among the most promising biomarkers for type II diabetes.4.Weighted gene co-expression networks have significant advantages over traditional differential gene analysis methods,and the study can yield many common results with traditional differential gene algorithms,while also being able to uncover other more meaningful gene information.