Mechanism Research On The Transcription Of IRF3 And IRF5 Gene Regulated By Long Noncoding RNA MALAT1

Objective: Validate whether IRF3 and IRF5 is regulated by long non-coding RNA MALAT1.Methods: Luciferase report plasmid pGL3-56 inserted with IRF3 promoter and MALAT1 knockdown siRNAs(negative control,siMALAT1-1 and siMALAT1-2)were co-transfected to A549 cells,then the luciferase activities were determined.MALAT1 knockdown siRNAs were transfected to A549 cells,then IRF3 mRNA and protein levels were detected by qPCR and western blotting respectively.Luciferase report plasmid pGL3-179 inserted with IRF5 promoter and MALAT1 knockdown siRNAs(negative control,siMALAT1-1 and siMALAT1-2)were co-transfected to A549 cells,then the luciferase activities were determined.MALAT1 knockdown siRNAs were transfected to A549 cells,then IRF3 mRNA and protein levels were detected by qPCR and western blotting respectively.The mRNA and protein levels of IRF5 and MALAT1 were verified in the database and patient samples.Results: 1.When MALAT1 was knocked down by siRNA,the relative luciferase activity of IRF3 and IRF5 decreased;2.When MALAT1 was knocked down by siRNA,mRNA levels and protein levels of IRF3 and IRF5 were decreased;3.In the GEO database,mRNA expression levels of MALAT1 and IRF5 in patients with type I lung cancer are low relative to paired normal lung tissue,and in patients with type II?III lung cancer,MATAL1 The mRNA expression levels of IRF5 and MALAT1 are highly expressed relative to paired normal lung tissues;4.We collected 19 cases of clinical type III II lung cancer patients and found that mRNA expression levels of MALAT1 and IRF5 were also highly expressed relative to matched normal lung tissues.Conclusion: IRF3 and IRF5 is a target of MALAT1 and MALAT1 regulates the expression of IRF3 and IRF5 by targeting IRF3 and IRF5 promoter.