人巨细胞病毒（HCMV）是围产期感染的主要病原，其增殖与围产期感染致病的机制尚未明确。前期研究发现HCMV感染可能通过宿主细胞环状RNA hsa_circ_0094088上调病毒miRNA miR-UL70-3p和miR-US4-3p水平，继而抑制miRNA靶点KSR2的表达，促进病毒增殖。本项目拟在HCMV增殖感染细胞模型中，首先调控环状RNA水平，检测病毒miRNA及增殖状态，探明环状RNA对miRNA和病毒增殖的作用；进一步调控miRNA水平，检测KSR2表达、RAS-PI3K通路激活和病毒增殖，明确病毒miRNA对KSR2-RAS-PI3K和病毒增殖的作用；最后检测miRNA水平对NF-κB通路激活、炎症反应和病毒增殖的影响，揭示病毒miRNA对KSR2-NF-κB和病毒增殖的作用。最终阐明HCMV感染与宿主非编码RNA间的调控机制，为围产期HCMV活动性感染的诊治提供理论依据。

Human cytomegalovirus (HCMV) is one major pathogen of perinatal infections, but its pathogenesis remains unknown. In our preliminary experiments, the level of circle RNA hsa_circ_0094088 was decreased after HCMV infection, and the levels of two viral miRNAs, miR-UL70-3p and miR-US4-3p, were increased. As a consequence, the level of KSR2 being the target of viral miRNAs was up-regulated, leading to promotion of HCMV proliferation. In this project, using HCMV-infected MRC-5 cells as the study object, we will examine the expression of miR-UL70-3p and miR-US4-3p as well as HCMV proliferation after regulation of hsa_circ_0094088 expression to understand the regulatory role of hsa_circ_0094088. Secondly, we will examine the expression of KSR2, activation of RAS-PI3K pathway, survival rate of MRC-5 and proliferation of HCMV after regulation of the expression of the above two viral miRNAs to understand the regulatory roles of miR-UL70-3p and miR-US4-3p on KSR2-RAS-PI3K pathway and the proliferation of HCMV. Last but not the least, we will examine the expression of KSR2, activation level of RAS-NF-κB pathway, inflammation reaction and HCMV proliferation after regulating the expression of the two viral miRNAs to understand the regulatory roles of miR-UL70-3p and miR-US4-3p on the KSR2-RAS-NF-κB pathway and the proliferation of HCMV. Through this study, we hope to illuminate the relationship between HCMV proliferation and the regulatory functions of host non-coding RNAs, and provide theory gist for the diagnosis and treatment of active HCMV infection in perinatal period.