Graduate Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, Massachusetts, United States of America.
Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, United States of America.
PLoS Pathog. 2019 Sep 13;15(9):e1008030. doi: 10.1371/journal.ppat.1008030. eCollection 2019 Sep.
Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with multiple human malignancies. EBV drives B-cell proliferation, which contributes to the pathogenesis of multiple lymphomas. Yet, knowledge of how EBV subverts host biosynthetic pathways to transform resting lymphocytes into activated lymphoblasts remains incomplete. Using a temporal proteomic dataset of EBV primary human B-cell infection, we identified that cholesterol and fatty acid biosynthetic pathways were amongst the most highly EBV induced. Epstein-Barr nuclear antigen 2 (EBNA2), sterol response element binding protein (SREBP) and MYC each had important roles in cholesterol and fatty acid pathway induction. Unexpectedly, HMG-CoA reductase inhibitor chemical epistasis experiments revealed that mevalonate pathway production of geranylgeranyl pyrophosphate (GGPP), rather than cholesterol, was necessary for EBV-driven B-cell outgrowth, perhaps because EBV upregulated the low-density lipoprotein receptor in newly infected cells for cholesterol uptake. Chemical and CRISPR genetic analyses highlighted downstream GGPP roles in EBV-infected cell small G protein Rab activation. Rab13 was highly EBV-induced in an EBNA3-dependent manner and served as a chaperone critical for latent membrane protein (LMP) 1 and 2A trafficking and target gene activation in newly infected and in lymphoblastoid B-cells. Collectively, these studies identify highlight multiple potential therapeutic targets for prevention of EBV-transformed B-cell growth and survival.
EB 病毒(EBV)可引起传染性单核细胞增多症,并与多种人类恶性肿瘤有关。EBV 驱动 B 细胞增殖,这有助于多种淋巴瘤的发病机制。然而,关于 EBV 如何颠覆宿主生物合成途径将静止淋巴细胞转化为活化的淋巴母细胞的知识仍然不完整。使用 EBV 原发性人 B 细胞感染的时间蛋白质组数据集,我们发现胆固醇和脂肪酸生物合成途径是 EBV 诱导程度最高的途径之一。EBV 核抗原 2(EBNA2)、固醇反应元件结合蛋白(SREBP)和 MYC 在胆固醇和脂肪酸途径诱导中都具有重要作用。出乎意料的是,HMG-CoA 还原酶抑制剂的化学上位性实验表明,甲羟戊酸途径产生的香叶基香叶基焦磷酸(GGPP)而不是胆固醇,是 EBV 驱动 B 细胞生长所必需的,这可能是因为 EBV 在新感染的细胞中上调了低密度脂蛋白受体以摄取胆固醇。化学和 CRISPR 遗传分析突出了 GGPP 在 EBV 感染细胞小 G 蛋白 Rab 激活中的下游作用。Rab13 以 EBNA3 依赖的方式高度诱导 EBV,并作为一种伴侣蛋白,对于潜伏膜蛋白(LMP)1 和 2A 的运输以及新感染和淋巴母细胞 B 细胞中的靶基因激活至关重要。总之,这些研究确定了多个潜在的治疗靶点,可用于预防 EBV 转化的 B 细胞生长和存活。