HSV-2-encoded miRNA-H4 Regulates Cell Cycle Progression and Act-Dinduced Apoptosis in HeLa Cells by Targeting CDKL2 and CDKN2A

MicroRNAs(miRNAs)encoded by latency-associated transcript are associated with both latent and acute stages of herpes simplex virus 2(HSV-2)infection.In this study,miRNA-H4-5p and miRNA-H4-3p were ectopically expressed in HeLa cells to explore potential cellular targets of viral miRNAs and demonstrate their potential biological functions.The results showed that miRNA-H4-5p could reverse apoptosis induced by actinomycin D(Act-D)and promote cell cycle progression,but miRNA-H4-3p had no such obvious functions.Bioinformatics analysis,luciferase report assay,quantitative reverse transcription polymerase chain reaction(qRT-PCR),and Western blotting demonstrated that miRNA-H4-5p could bind to the 3-′untranslated region(UTR)of cyclin-dependent kinase inhibitor 2A(CDKN2A)and cyclin-dependent kinase-like 2(CDKL2)to negatively regulate their expression.We verified that these two targeted genes were associated with cell apoptosis and cell cycle.Furthermore,in HeLa cells infected with HSV-2,we detected significantly reduced expression of CDKN2A and CDKL2 and demonstrated the negative regulation effect of miRNA-H4-5p on these two target genes.Our findings show that viral miRNAs play a vital role in regulating the expression of the host's cellular genes that participate in cell apoptosis and progression to reshape the cellular environment in response to HSV-2 infection,providing further information on the roles of encoded herpesvirus miRNAs in pathogen-host interaction.