GO And KEGG Network Analysis Applied For Goat Atrial Fibrillation Models By RNA-seq

BackgroundAtrial fibrillation(AF)is the most common arrhythmia and is closely related to the increase of stroke and heart failure.The pathophysiology of AF has been studied for nearly a century.At present,it is believed that the molecular mechanisms of its occurrence and maintenance include:atrial electrical reconstruction,structural remodeling,contractile reconstruction,autonomic nerve reconstruction,oxidative stress,and inflammation.However,it is not complete and further research is needed.ObjectiveIn this study,we established goats atrial fibrillation models and used deep sequencing to explore the expression profile of mRNAs transcriptome;to reveal the development mechanism of AF from the molecular level and provide potential targets for optimizing the treatment of AF.Methods1.Fourteen healthy male goats with similar age are randomly divided into two groups,control group(n=7)and AFgroup(n=7).The electrode leads were inserted into the left atria in the two groups underwent surgery.The AF group underwent rapid pacing(600 beats/min)for four weeks to establish goats AF models,while the control group was the same as AF group but without pacing.Cardiac electrophysiological tests were performed before and four weeks after the surgery,include atrial effective refractory period(AERP)and burst.The left atrial appendage tissue samples were stored until use.2.Sequencing analysis and verificationThe total RNAs were isolated from left atrial appendage tissue.The differentially expressed profiles of mRNAs were examined through sequencing analysis.Three mRNA transcripts were randomly selected,and their expression levels were analyzed by real-time quantitative PCR(qRT-PCR)to verify the sequencing results3.Bioinformatics analysisGene Ontology(GO)functional analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis were performed to reveal and annotate the differentially expressed transcriptsResults1.The goats AF models were successfully built through left atrial tachypacing.Compared with control group,the AERP was significantly shortened(P<0.05)2.Through RNA-seq analysis of left atrial appendage tissue from AF and control group,1079 mRNAs transcripts meet the pipelines that Fold change is more than 1.5 times and P<0.05.And among them,757 transcripts up-regulated and 322 transcripts were down-regulation.Three mRNAs were randomly selected and verified by qRT-PCR method,which proved that the sequencing results were true and reliable3.Go enrichment analysis showed that the differentially expressed genes were mainly involved in the biological processes,such as metabolism,extracellular matrix,immune response and so on;And the KEGG pathway analysis showed that the differentially expressed genes were mainly involved in oxidative phosphorylation,myocardial contraction,tumor necrosis factor and NF-?B pathways and so onConclusions1.There existed abberantly expressed mRNAs transcripts in left atrial appendage tissue of AF and non-AF goats models.These differently mRNAs were closely related to the development of tissue remodeling during AF2.Go enrichment analysis and KEGG pathway analysis,showed that the differentially expressed genes were mainly involved extracellular matrix,leukocyte chemotaxis,oxidative phosphorylation,myocardial contraction,tumor necrosis factor,cell adhesion molecule,NF-?B.Based on the constructed pathway molecular cascade network,we screened ITGAM and COL1A1.They as a key element may be in the occurrence and maintenance of AF...