Septin9通过与埃博拉病毒VP35互作调节包涵体形成促进病毒复制

Septin9 promotes viral replication by interacting with Ebola virus VP35 to regulate inclusion body formation

摘要:

埃博拉病毒(Ebola virus, EBOV)作为丝状病毒科高致病性的病原体，可导致人类严重出血热。为了解其复制过程中的分子机制，开发有效的抗病毒策略，本研究通过VP35-TurboID免疫沉淀结合定量质谱分析，发现Septin9是VP35的相互作用蛋白，Septin9蛋白在细胞骨架调节中起重要作用。使用Western blotting以及Far-Western blotting等方法证实Septin9与VP35存在直接相互作用，并证明VP35的C端区域是关键结合域。此外，利用埃博拉病毒最小基因组系统(EBOV minigenome, EBOV MG)，通过转录复制病毒样颗粒(transcription- and replication-competent virus-like particles, trVLPs)证实敲低Septin9显著抑制了EBOV的复制以及病毒包涵体(viral inclusion bodies, VIBs)的形成。本研究发现VP35能够结合GTP结合蛋白Septin9，通过破坏包涵体抑制EBOV复制。本研究深化了对EBOV致病机制的认知，为开发针对EBOV的新型治疗策略提供了理论依据与实证支持。

Abstract:

The Ebola virus (EBOV), a member of the Filoviridae family, is a highly pathogenic agent responsible for severe hemorrhagic fever in humans. Understanding the molecular mechanisms governing its replication is critical for developing effective antiviral strategies. VP35-TurboID immunosuppression coupled with quantitative mass spectrometry identified Septin9, the host GTP-binding protein which played a role in cytoskeletal regulation, as a novel interactor of VP35. Western blotting and Far-Western blotting confirmed the direct interaction and demonstrated that the C-terminal region of VP35 was the critical binding domain. Functionally, EBOV replication as well as the formation of viral inclusion bodies (VIBs) was demonstrated to be significantly suppressed by Septin9 knockdown and depletion, as shown by the EBOV minigenome (EBOV MG) and the transcription- and replication-competent virus-like particles (trVLPs) system. This study reveals that VP35 engages in a specific interaction with the GTP-binding protein Septin9, thereby impeding EBOV replication through the disruption of inclusion bodies. The overarching objective of this study is to significantly enhance our understanding about the pathogenic mechanism of EBOV and offer a robust theoretical foundation and solid empirical support for the formulation of innovative therapeutic strategies against EBOV.