Muneer Adil, Xie Ling, Xie Xuping, Zhang Feng, Wrobel John A, Xiong Yan, Yu Xufen, Wang Charles, Gheorghe Ciprian, Wu Ping, Song Juan, Ming Guo-Li, Jin Jian, Song Hongjun, Shi Pei-Yong, Chen Xian
bioRxiv. 2024 Mar 6:2024.03.04.583415. doi: 10.1101/2024.03.04.583415.
By largely unknown mechanism(s), SARS-CoV-2 hijacks the host translation apparatus to promote COVID-19 pathogenesis. We report that the histone methyltransferase G9a noncanonically regulates viral hijacking of the translation machinery to bring about COVID-19 symptoms of hyperinflammation, lymphopenia, and blood coagulation. Chemoproteomic analysis of COVID-19 patient peripheral mononuclear blood cells (PBMC) identified enhanced interactions between SARS-CoV-2-upregulated G9a and distinct translation regulators, particularly the N -methyladenosine (m A) RNA methylase METTL3. These interactions with translation regulators implicated G9a in translational regulation of COVID-19. Inhibition of G9a activity suppressed SARS-CoV-2 replication in human alveolar epithelial cells. Accordingly, multi-omics analysis of the same alveolar cells identified SARS-CoV-2-induced changes at the transcriptional, m A-epitranscriptional, translational, and post-translational (phosphorylation or secretion) levels that were reversed by inhibitor treatment. As suggested by the aforesaid chemoproteomic analysis, these multi-omics-correlated changes revealed a G9a-regulated translational mechanism of COVID-19 pathogenesis in which G9a directs translation of viral and host proteins associated with SARS-CoV-2 replication and with dysregulation of host response. Comparison of proteomic analyses of G9a inhibitor-treated, SARS-CoV-2 infected cells, or culture of patient PBMCs, with COVID-19 patient data revealed that G9a inhibition reversed the patient proteomic landscape that correlated with COVID-19 pathology/symptoms. These data also indicated that the G9a-regulated, inhibitor-reversed, translational mechanism outperformed G9a-transcriptional suppression to ultimately determine COVID-19 pathogenesis and to define the inhibitor action, from which biomarkers of serve symptom vulnerability were mechanistically derived. This cell line-to-patient conservation of G9a-translated, COVID-19 proteome suggests that G9a inhibitors can be used to treat patients with COVID-19, particularly patients with long-lasting COVID-19 sequelae.
通过 largely unknown mechanism(s)，严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）劫持宿主翻译装置以促进冠状病毒病 2019（COVID-19）的发病机制。我们报告组蛋白甲基转移酶 G9a 以非经典方式调节病毒对翻译机制的劫持，从而引发 COVID-19 的过度炎症、淋巴细胞减少和血液凝固症状。对 COVID-19 患者外周血单个核细胞（PBMC）的化学蛋白质组学分析确定了 SARS-CoV-2 上调的 G9a 与不同翻译调节因子之间增强的相互作用，特别是 N -甲基腺苷（m A）RNA 甲基化酶 METTL3。这些与翻译调节因子的相互作用表明 G9a 参与了 COVID-19 的翻译调控。抑制 G9a 活性可抑制 SARS-CoV-2 在人肺泡上皮细胞中的复制。因此，对同一肺泡细胞的多组学分析确定了 SARS-CoV-2 诱导的转录、m A 表观转录、翻译和翻译后（磷酸化或分泌）水平的变化，这些变化可被抑制剂处理逆转。如上述化学蛋白质组学分析所表明的，这些多组学相关变化揭示了一种 G9a 调节的 COVID-19 发病机制的翻译机制，其中 G9a 指导与 SARS-CoV-2 复制以及宿主反应失调相关的病毒和宿主蛋白的翻译。将 G9a 抑制剂处理的、SARS-CoV-2 感染的细胞或患者 PBMC 的蛋白质组学分析与 COVID-19 患者数据进行比较，发现抑制 G9a 可逆转与 COVID-19 病理/症状相关的患者蛋白质组格局。这些数据还表明，G9a 调节的、抑制剂逆转的翻译机制优于 G9a 转录抑制，最终决定 COVID-19 的发病机制并确定抑制剂的作用，从中机械性地推导出发病症状易感性的生物标志物。这种从细胞系到患者的 G9a 翻译的 COVID-19 蛋白质组的保守性表明，G9a 抑制剂可用于治疗 COVID-19 患者，特别是患有长期 COVID-19 后遗症的患者。
