Inhibition of Ebola virus entry by a C-peptide targeted to endosomes.
Inhibition of Ebola virus entry by a C-peptide targeted to endosomes.
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DOI：
10.1074/jbc.m110.207084
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发表时间：
2011-05-06
期刊：
影响因子：
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通讯作者：
Chandran K
中科院分区：
文献类型：
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作者：
Miller EH;Harrison JS;Radoshitzky SR;Higgins CD;Chi X;Dong L;Kuhn JH;Bavari S;Lai JR;Chandran K
埃博拉病毒（EboV）和马尔堡病毒（MarV）（丝状病毒）是严重出血热的病原体。感染开始于将颗粒摄取到细胞内体中，其中病毒包膜糖蛋白（GP）催化病毒和宿主细胞膜之间的融合。该融合事件被认为涉及包膜刺突的跨膜亚基（GP 2）的构象重排，其最终导致由GP 2的N-和C-末端七肽重复（分别为NHR和NHR）区域形成六螺旋束。采用类似病毒进入机制的其他病毒（如HIV-1和严重急性呼吸综合征冠状病毒）的感染可以用对应于天然C13序列的合成肽（“C肽”）抑制。然而，先前报道的EboV C肽显示出弱的或不显著的抗病毒活性。为了确定C肽的活性是否可以通过增加其细胞内浓度来改善，我们制备了与来自HIV-1达特的富含精氨酸的序列缀合的EboV C肽，已知所述富含精氨酸的序列在内体中积累。我们发现，这种肽特异性地抑制由丝状病毒GP蛋白介导的病毒进入和真实丝状病毒的感染。我们确定了抗病毒活性依赖于达特序列和天然EboV的Tat序列。机制研究表明，肽的作用，通过阻断膜融合中间体。
Ebola virus (EboV) and Marburg virus (MarV) (filoviruses) are the causative agents of severe hemorrhagic fever. Infection begins with uptake of particles into cellular endosomes, where the viral envelope glycoprotein (GP) catalyzes fusion between the viral and host cell membranes. This fusion event is thought to involve conformational rearrangements of the transmembrane subunit (GP2) of the envelope spike that ultimately result in formation of a six-helix bundle by the N- and C-terminal heptad repeat (NHR and CHR, respectively) regions of GP2. Infection by other viruses employing similar viral entry mechanisms (such as HIV-1 and severe acute respiratory syndrome coronavirus) can be inhibited with synthetic peptides corresponding to the native CHR sequence (“C-peptides”). However, previously reported EboV C-peptides have shown weak or insignificant antiviral activity. To determine whether the activity of a C-peptide could be improved by increasing its intracellular concentration, we prepared an EboV C-peptide conjugated to the arginine-rich sequence from HIV-1 Tat, which is known to accumulate in endosomes. We found that this peptide specifically inhibited viral entry mediated by filovirus GP proteins and infection by authentic filoviruses. We determined that antiviral activity was dependent on both the Tat sequence and the native EboV CHR sequence. Mechanistic studies suggested that the peptide acts by blocking a membrane fusion intermediate.