Next Article in Journal
Pharmacological Inhibition of Feline Immunodeficiency Virus (FIV)
Next Article in Special Issue
Herpes Virus Fusion and Entry: A Story with Many Characters
Previous Article in Journal
Spatial Vulnerability: Bacterial Arrangements, Microcolonies, and Biofilms as Responses to Low Rather than High Phage Densities
Previous Article in Special Issue
Paramyxovirus Fusion and Entry: Multiple Paths to a Common End
Article Menu

Export Article

Open AccessReview
Viruses 2012, 4(5), 688-707;

Poxvirus Cell Entry: How Many Proteins Does it Take?

Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
Received: 10 April 2012 / Revised: 21 April 2012 / Accepted: 23 April 2012 / Published: 27 April 2012
(This article belongs to the Special Issue Virus-Induced Membrane Fusion)
Full-Text   |   PDF [694 KB, uploaded 12 May 2015]   |  


For many viruses, one or two proteins enable cell binding, membrane fusion and entry. The large number of proteins employed by poxviruses is unprecedented and may be related to their ability to infect a wide range of cells. There are two main infectious forms of vaccinia virus, the prototype poxvirus: the mature virion (MV), which has a single membrane, and the extracellular enveloped virion (EV), which has an additional outer membrane that is disrupted prior to fusion. Four viral proteins associated with the MV membrane facilitate attachment by binding to glycosaminoglycans or laminin on the cell surface, whereas EV attachment proteins have not yet been identified. Entry can occur at the plasma membrane or in acidified endosomes following macropinocytosis and involves actin dynamics and cell signaling. Regardless of the pathway or whether the MV or EV mediates infection, fusion is dependent on 11 to 12 non-glycosylated, transmembrane proteins ranging in size from 4- to 43-kDa that are associated in a complex. These proteins are conserved in poxviruses making it likely that a common entry mechanism exists. Biochemical studies support a two-step process in which lipid mixing of viral and cellular membranes is followed by pore expansion and core penetration. View Full-Text
Keywords: vaccinia virus entry; viral membrane fusion; endocytosis; macropinocytosis; transmembrane proteins vaccinia virus entry; viral membrane fusion; endocytosis; macropinocytosis; transmembrane proteins

Figure 1

This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Share & Cite This Article

MDPI and ACS Style

Moss, B. Poxvirus Cell Entry: How Many Proteins Does it Take? Viruses 2012, 4, 688-707.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Viruses EISSN 1999-4915 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top