Department of BioBank, Affiliated Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China.
Department of Pediatrics, Zhangjiagang First People's Hospital, Zhangjiagang, Jiangsu 215600, P.R. China.
Mol Med Rep. 2018 Mar;17(3):4657-4664. doi: 10.3892/mmr.2018.8419. Epub 2018 Jan 10.
Human cytomegalovirus (HCMV) infection is the primary viral cause of congenital abnormalities and mental retardation in newborns. The HCMV UL141‑encoded glycoprotein has been previously revealed to inhibit the cell‑surface expression of cluster of differentiation (CD)155, CD122, tumor necrosis factor‑related apoptosis‑inducing ligand death (TRAIL)‑receptor 1 (R1) and TRAIL‑receptor 2 (R2), thus protecting virally‑infected cells by allowing them to escape natural killer cell‑mediated cytotoxicity. The present study investigated the interaction between HCMV UL141 and human fetal brain cDNA to elucidate the possible effects of UL141 on the nervous system. The findings of the current study demonstrate that the HCMV UL141 protein directly interacts with the human protein CUGBP Elav‑like family member 5 (CELF5) via yeast two‑hybrid screening, this interaction was confirmed by glutathione S‑transferase pull‑down and co‑immunoprecipitation assays. Additionally, the present study demonstrated that the UL141 protein co‑localizes with CELF5 in the cytoplasm of 293 cells using fluorescence confocal microscopy. CELF5 overexpression in a stably‑expressing cell line significantly increased viral DNA copy number and titer in HCMV‑infected U373MG cells. However, reducing CELF5 expression via specific small interfering RNAs did not affect viral DNA copy number or titer in HCMV‑infected cells. The current findings suggest that the interaction between UL141 and CELF5 may be involved in modulating viral DNA synthesis and progeny production. Therefore, CELF5 may represent a possible mechanism for regulation of HCMV genomic DNA synthesis, which is a key step during HCMV infection leading to neurological disease.
人巨细胞病毒（HCMV）感染是导致新生儿先天畸形和智力迟钝的主要病毒原因。先前已经揭示，HCMV UL141 编码的糖蛋白抑制细胞表面分化（CD）155、CD122、肿瘤坏死因子相关凋亡诱导配体死亡（TRAIL）受体 1（R1）和 TRAIL 受体 2（R2）的表达，从而通过允许受感染的细胞逃避自然杀伤细胞介导的细胞毒性来保护病毒感染的细胞。本研究通过人类胎儿脑 cDNA 与 HCMV UL141 的相互作用，探讨 UL141 对神经系统的可能影响。本研究发现，通过酵母双杂交筛选，HCMV UL141 蛋白直接与人类蛋白 CUGBP Elav 样家族成员 5（CELF5）相互作用，该相互作用通过谷胱甘肽 S-转移酶下拉和共免疫沉淀试验得到证实。此外，本研究通过荧光共聚焦显微镜显示，UL141 蛋白与 CELF5 在 293 细胞的细胞质中共定位。在稳定表达细胞系中过表达 CELF5 可显著增加 HCMV 感染的 U373MG 细胞中的病毒 DNA 拷贝数和滴度。然而，通过特异性的小干扰 RNA 降低 CELF5 的表达不会影响 HCMV 感染细胞中的病毒 DNA 拷贝数或滴度。目前的研究结果表明，UL141 和 CELF5 之间的相互作用可能参与调节病毒 DNA 的合成和子代产物的产生。因此，CELF5 可能是调节 HCMV 基因组 DNA 合成的可能机制之一，HCMV 感染导致神经疾病的关键步骤是 HCMV 基因组 DNA 的合成。
