The Coronavirus E Protein: Assembly and Beyond

Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Viruses (Impact Factor: 3.35). 03/2012; 4(3):363-82. DOI: 10.3390/v4030363
Source: PubMed


The coronavirus E protein is a small membrane protein that has an important role in the assembly of virions. Recent studies have indicated that the E protein has functions during infection beyond assembly, including in virus egress and in the host stress response. Additionally, the E protein has ion channel activity, interacts with host proteins, and may have multiple membrane topologies. The goal of this review is to highlight the properties and functions of the E protein, and speculate on how they may be related.

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Available from: Carolyn E Machamer,
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    • "The ion-channel activity of p7 in this assay could be abrogated by the drug Amantadine (Griffin et al., 2003). The ionchannel activity of a cross-linked p7 lead to inclusion of this protein in the viroporin family, which consists of small hydrophobic proteins with the ability to permeabilize membranes for ion and small molecule movement (examples are listed in Table 1 and reviewed in (Nieva et al., 2012; Gonzalez and Carrasco, 2003; Wang et al., 2011; Liang and Li, 2010; Ruch and Machamer, 2012)). An important example is the viral protein M2 of influenza virus, which forms proton ion-channels and is activated in acidic environments. "
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    ABSTRACT: Hepatitis C virus (HCV) is a major global health burden with 2-3% of the world׳s population being chronically infected. Persistent infection can lead to cirrhosis and hepatocellular carcinoma. Recently available treatment options show enhanced efficacy of virus clearance, but are associated with resistance and significant side effects. This warrants further research into the basic understanding of viral proteins and their pathophysiology. The p7 protein of HCV is an integral membrane protein that forms an ion-channel. The role of p7 in the HCV life cycle is presently uncertain, but most of the research performed to date highlights its role in the virus assembly process. The aim of this review is to provide an overview of the literature investigating p7, its structural and functional details, and to summarize the developments to date regarding potential anti-p7 compounds. A better understanding of this protein may lead to development of a new and effective therapy.
    Virology 07/2014; 462-463(1). DOI:10.1016/j.virol.2014.04.018 · 3.32 Impact Factor
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    • "Nevertheless , high amounts of E protein are accumulated within cells during viral infection, suggesting an important role of this protein during virus cycle. CoV E protein mainly distributes between ER and Golgi apparatus membranes where it actively participates in virus budding, morphogenesis and trafficking (Corse and Machamer, 2000; Lim and Liu, 2001; Nal et al., 2005; Nguyen and Hogue, 1997; Raamsman et al., 2000; Ruch and Machamer, 2012a). Particularly, SARS-CoV E protein mainly localizes in the endoplasmic reticulum–Golgi intermediate compartment (ERGIC) when expressed alone or during virus infection (Nieto-Torres Contents lists available at SciVerse ScienceDirect journal homepage: "
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    ABSTRACT: Coronavirus (CoV) envelope (E) protein ion channel activity was determined in channels formed in planar lipid bilayers by peptides representing either the transmembrane domain of severe acute respiratory syndrome CoV (SARS-CoV) E protein, or the full-length E protein. Both of them formed a voltage independent ion conductive pore with symmetric ion transport properties. Mutations N15A and V25F located in the transmembrane domain prevented the ion conductivity. E protein derived channels showed no cation preference in non-charged lipid membranes, whereas they behaved as pores with mild cation selectivity in negatively-charged lipid membranes. The ion conductance was also controlled by the lipid composition of the membrane. Lipid charge also regulated the selectivity of a HCoV-229E E protein derived peptide. These results suggested that the lipids are functionally involved in E protein ion channel activity, forming a protein-lipid pore, a novel concept for CoV E protein ion channel entity.
    Virology 07/2012; 432(2):485-94. DOI:10.1016/j.virol.2012.07.005 · 3.32 Impact Factor
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    ABSTRACT: Enveloped viruses acquire their membrane from the host cell and accordingly need to separate their envelope from cellular membranes via membrane fission. Although some of the enveloped viruses recruit the endosomal sorting complex required for transport (ESCRT) to catalyze the final fission reaction, many enveloped viruses seem to bud in an ESCRT-independent manner. Here we describe the principles that govern membrane fission reactions in general and review progress in the understanding of ESCRT-mediated membrane fission. We relate ESCRT function to budding of single stranded RNA viruses and discuss alternative ways to mediate membrane fission that may govern ESCRT-independent budding.
    04/2013; 3(2). DOI:10.1016/j.coviro.2013.03.011
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