1.W.4.  The Viral Portal Protein 4 (PPP4) Family 

Members of this family from eukaryotic viruses form portals in the viral capsid through which viral DNA is translocated during DNA packaging. The protein assembles as a dodecamer at a single fivefold axis of the T=16 icosahedric capsid. It binds to the molecular motor that translocates the viral DNA, termed terminase (Newcomb et al. 2001).


 

References:

D√ľnn-Kittenplon, D., A. Ashkenazy-Titelman, I. Kalt, J.P. Lellouche, Y. Shav-Tal, and R. Sarid. (2021). The Portal Vertex of KSHV Promotes Docking of Capsids at the Nuclear Pores. Viruses 13:.

Newcomb, W.W., R.M. Juhas, D.R. Thomsen, F.L. Homa, A.D. Burch, S.K. Weller, and J.C. Brown. (2001). The UL6 gene product forms the portal for entry of DNA into the herpes simplex virus capsid. J. Virol. 75: 10923-10932.

Examples:

TC#NameOrganismal TypeExample
1.W.4.1.1

UL6 portal protein of 676 aas for entry of DNA into the viral capsid (Newcomb et al. 2001).

UL6 portal protein of Human herpesvirus 1 (strain 17) (HHV-1) (Human herpes simplex virus 1)

 
1.W.4.1.2

Uncharacterized viral protein of 503 aas Human betaherpesvirus 6 (HHV-6)

UP of Human β-herpesvirus 6 (HHV-6)

 
1.W.4.1.3

TSC22 domain family protein 2 isoform X3 of 583 aa

TSC22 protein of Oryzias latipes

 
1.W.4.1.4

Capsid portal protein of 712 aas

PP of Psittacid herpesvirus 5

 
1.W.4.1.5

Uncharacterized protein of 441 aas.  This protein is annotated as a partial sequence from a bacterium.  Several fragmentary proteins from bacteria are present in the NCBI protein database that are homologous with the members of this family.  Whether these are errors or valid fragments from the sources indicated by the annotations has not been determined.

UP of Cellulomonas oligotrophica

 
1.W.4.1.6

ORF43 portal protein of 605 aas. It forms a portal in the viral capsid through which viral DNA is translocated during DNA packaging. It assembles as a dodecamer at a single fivefold axe of the T=16 icosahedric capsid and binds to the molecular motor that translocates the viral DNA, termed terminase, The KSHV icosahedral capsid includes a portal vertex, composed of 12 protein subunits encoded by open reading frame (ORF) 43, which enables packaging and release of the viral genome into the nucleus through the nuclear pore complex (NPC) (Dünn-Kittenplon et al. 2021). ORF43 enables packaging and release of the viral genome into the nucleus through the nuclear pore complex (NPC). Capsid vertex-specific component (CVSC) tegument proteins, which directly mediate docking at the NPCs, are organized on the capsid vertices and are enriched on the portal vertex. The portal vertex of KSHV promotes docking of capsids at nuclear pores (Dünn-Kittenplon et al. 2021). The tegument proteins (e.g., E5LBZ1) directly mediates docking at the NPC.

ORF43 portal protein of Human herpesvirus 8 (HHV-8) (Kaposi's sarcoma-associated herpesvirus)

 
Examples:

TC#NameOrganismal TypeExample
1.W.4.2.1

VP4 protein of 642 aas

VP4 of african horse sickness virus