| Structural highlights
Function
[POLG_POL1M] Capsid proteins VP1, VP2, VP3 and VP4 form a closed capsid enclosing the viral positive strand RNA genome. VP4 lies on the inner surface of the protein shell formed by VP1, VP2 and VP3. All the three latter proteins contain a beta-sheet structure called beta-barrel jelly roll. Together they form an icosahedral capsid (T=3) composed of 60 copies of each VP1, VP2, and VP3, with a diameter of approximately 300 Angstroms. VP1 is situated at the 12 fivefold axes, whereas VP2 and VP3 are located at the quasi-sixfold axes. The interaction of five VP1 proteins in the fivefold axes results in a prominent protusion extending to about 25 Angstroms from the capsid shell. The resulting structure appears as a steep plateau encircled by a valley or cleft. This depression also termed canyon is the receptor binding site. The capsid interacts with human PVR at this site to provide virion attachment to target cell. This attachment induces virion internalization predominantly through clathrin- and caveolin-independent endocytosis in Hela cells and through caveolin-mediated endocytosis in brain microvascular endothelial cells. VP4 and VP1 subsequently undergo conformational changes leading to the formation of a pore in the endosomal membrane, thereby delivering the viral genome into the cytoplasm.[1] [2] [3] VP0 precursor is a component of immature procapsids (By similarity).[4] [5] [6] Protein 2A is a cysteine protease that is responsible for the cleavage between the P1 and P2 regions. It cleaves the host translation initiation factor EIF4G1, in order to shut down the capped cellular mRNA transcription.[7] [8] [9] Protein 2B affects membrane integrity and cause an increase in membrane permeability (By similarity).[10] [11] [12] Protein 2C associates with and induces structural rearrangements of intracellular membranes. It displays RNA-binding, nucleotide binding and NTPase activities.[13] [14] [15] Protein 3A, via its hydrophobic domain, serves as membrane anchor. It also inhibits endoplasmic reticulum-to-Golgi transport (By similarity).[16] [17] [18] Protein 3C is a cysteine protease that generates mature viral proteins from the precursor polyprotein. In addition to its proteolytic activity, it binds to viral RNA, and thus influences viral genome replication. RNA and substrate bind co-operatively to the protease (By similarity).[19] [20] [21] RNA-directed RNA polymerase 3D-POL replicates genomic and antigenomic RNA by recognizing replications specific signals (By similarity).[22] [23] [24]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Poliovirus provides a well-characterized system for understanding how nonenveloped viruses enter and infect cells. Upon binding its receptor, poliovirus undergoes an irreversible conformational change to the 135S cell entry intermediate. This transition involves shifts of the capsid protein beta barrels, accompanied by the externalization of VP4 and the N terminus of VP1. Both polypeptides associate with membranes and are postulated to facilitate entry by forming a translocation pore for the viral RNA. We have calculated cryo-electron microscopic reconstructions of 135S particles that permit accurate placement of the beta barrels, loops, and terminal extensions of the capsid proteins. The reconstructions and resulting models indicate that each N terminus of VP1 exits the capsid though an opening in the interface between VP1 and VP3 at the base of the canyon that surrounds the fivefold axis. Comparison with reconstructions of 135S particles in which the first 31 residues of VP1 were proteolytically removed revealed that the externalized N terminus is located near the tips of propeller-like features surrounding the threefold axes rather than at the fivefold axes, as had been proposed in previous models. These observations have forced a reexamination of current models for the role of the 135S particle in transmembrane pore formation and suggest testable alternatives.
The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes.,Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM J Virol. 2005 Jun;79(12):7745-55. PMID:15919927[25]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Ventoso I, MacMillan SE, Hershey JW, Carrasco L. Poliovirus 2A proteinase cleaves directly the eIF-4G subunit of eIF-4F complex. FEBS Lett. 1998 Sep 11;435(1):79-83. PMID:9755863
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
- ↑ Bergelson JM. New (fluorescent) light on poliovirus entry. Trends Microbiol. 2008 Feb;16(2):44-7. doi: 10.1016/j.tim.2007.12.004. Epub 2008 , Jan 10. PMID:18191571 doi:10.1016/j.tim.2007.12.004
- ↑ Bubeck D, Filman DJ, Cheng N, Steven AC, Hogle JM, Belnap DM. The structure of the poliovirus 135S cell entry intermediate at 10-angstrom resolution reveals the location of an externalized polypeptide that binds to membranes. J Virol. 2005 Jun;79(12):7745-55. PMID:15919927 doi:79/12/7745
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