HHV capsid portal protein

HHV capsid portal protein
Identifiers
Organism?
SymbolUL6
UniProtP10190
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StructuresSwiss-model
DomainsInterPro

HHV Capsid Portal Protein, or HSV-1 UL-6 protein, is the protein which forms a cylindrical portal in the capsid of Herpes simplex virus (HSV-1). The protein is commonly referred to as the HSV-1 UL-6 protein because it is the transcription product of Herpes gene UL-6.

The Herpes viral DNA enters and exits the capsid via the capsid portal. The capsid portal is formed by twelve copies of portal protein arranged as a ring; the proteins contain a leucine zipper sequence of amino acids which allow them to adhere to each other.[1] Each icosahedral capsid contains a single portal, located in one vertex.[2][3]

The portal is formed during initial capsid assembly and interacts with scaffolding proteins that construct the procapsid.[4] [5] [6] When the capsid is nearly complete, the viral DNA enters the capsid (i.e., the DNA is encapsidated) by a mechanism involving the portal and a DNA-binding protein complex similar to bacteriophage terminase.[7] Multiple studies suggest an evolutionary relationship between Capsid Portal Protein and bacteriophage portal proteins.[2][7]

When a virus infects a cell, it is necessary for the viral DNA to be released from the capsid. The Herpes virus DNA exits through the capsid portal.[8]

The genetic sequence of HSV-1 gene UL-6 is conserved across the family Herpesviridae and this family of genes is known as the "Herpesvirus UL6-like" gene family.[9] "UL-6" is nomenclature meaning that the protein is genetically encoded by the sixth (6th) open reading frame found in the viral genome segment named "Unique-Long (UL)".

  1. ^ Cardone G, Winkler DC, Trus BL, Cheng N, Heuser JE, Newcomb WW, Brown JC, Steven AC (2007-05-10). "Visualization of the herpes simplex virus portal in situ by cryo-electron tomography". Virology. 361 (2): 426–34. doi:10.1016/j.virol.2006.10.047. PMC 1930166. PMID 17188319.
  2. ^ a b Trus BL, Cheng N, Newcomb WW, Homa FL, Brown JC, Steven AC (November 2004). "Structure and polymorphism of the UL6 portal protein of herpes simplex virus type 1". Journal of Virology. 78 (22): 12668–71. doi:10.1128/JVI.78.22.12668-12671.2004. PMC 525097. PMID 15507654.(Article: [1])
  3. ^ Nellissery JK, Szczepaniak R, Lamberti C, Weller SK (2007-06-20). "A putative leucine zipper within the HSV-1 UL6 protein is required for portal ring formation". Journal of Virology. 81 (17): 8868–77. doi:10.1128/JVI.00739-07. PMC 1951442. PMID 17581990.
  4. ^ Newcomb WW, Homa FL, Brown JC (August 2005). "Involvement of the portal at an early step in herpes simplex virus capsid assembly". Journal of Virology. 79 (16): 10540–6. doi:10.1128/JVI.79.16.10540-10546.2005. PMC 1182615. PMID 16051846.
  5. ^ Newcomb WW, Thomsen DR, Homa FL, Brown JC (September 2003). "Assembly of the herpes simplex virus capsid: identification of soluble scaffold-portal complexes and their role in formation of portal-containing capsids". Journal of Virology. 77 (18): 9862–71. doi:10.1128/JVI.77.18.9862-9871.2003. PMC 224603. PMID 12941896. (Article: [2])
  6. ^ Singer GP, Newcomb WW, Thomsen DR, Homa FL, Brown JC (2005). "Identification of a region in the herpes simplex virus scaffolding protein required for interaction with the portal". Journal of Virology. 79 (1): 132–9. doi:10.1128/JVI.79.1.132-139.2005. PMC 538710. PMID 15596809.
  7. ^ a b White CA, Stow ND, Patel AH, Hughes M, Preston VG (June 2003). "Herpes Simplex Virus Type 1 Portal Protein UL6 Interacts with the Putative Terminase Subunits UL15 and UL28". Journal of Virology. 77 (11): 6351–8. doi:10.1128/JVI.77.11.6351-6358.2003. PMC 154995. PMID 12743292.
  8. ^ Newcomb WW, Booy FP, Brown JC (2007-05-13). "Uncoating the Herpes Simplex Virus Genome". Journal of Molecular Biology. 370 (4): 633–42. doi:10.1016/j.jmb.2007.05.023. PMC 1975772. PMID 17540405.
  9. ^ Herpesvirus UL6 like Conserved Domains view at NCBI