P03274 (CAP6_ADE02) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Pre-protein VI
Short name=pVI

Cleaved into the following 2 chains:

1. Endosome lysis protein
2. Protease cofactor
   Alternative name(s):
   pVI-C

Gene names

ORF Names:

L3

Organism

Human adenovirus C serotype 2 (HAdV-2) (Human adenovirus 2) [Reference proteome]

Taxonomic identifier

10515 [NCBI]

Taxonomic lineage

Viruses › dsDNA viruses, no RNA stage › Adenoviridae › Mastadenovirus › Human adenovirus C

Virus host

Homo sapiens (Human) [TaxID: 9606]

Protein attributes

Sequence length	250 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Pre-protein VI: During virus assembly, promotes hexon trimers nuclear import through nuclear pore complexes via an importin alpha/beta-dependent mechanism. By analogy to herpesviruses capsid assembly, might act as a scaffold protein to promote the formation of the icosahedral capsid. Ref.8 Ref.9 Ref.10 Ref.11 Ref.12 Ref.13 Endosome lysis protein: Structural component of the virion that provides increased stability to the particle shell through its interaction with the core-capsid bridging protein. Fibers shedding during virus entry into host cell allows the endosome lysis protein to be exposed as a membrane-lytic peptide. Exhibits pH-independent membrane fragmentation activity and probably mediates viral rapid escape from host endosome via organellar membrane lysis. It is not clear if it then remains partially associated with the capsid and involved in the intracellular microtubule-dependent transport of capsid to the nucleus, or if it is lost during endosomal penetration. Ref.8 Ref.9 Ref.10 Ref.11 Ref.12 Ref.13 Protease cofactor: Cofactor that activates the viral protease. Binds to viral protease in a 1:1 ratio. Ref.8 Ref.9 Ref.10 Ref.11 Ref.12 Ref.13
Subunit structure	Pre-protein VI: Interacts with hexon protein; this interaction allows nuclear import of hexon trimers and possibly pre-capsid assembly. Interacts (via C-terminal NLS) with importin alpha/beta. Endosome lysis protein: Interacts (via PPxY motif) with host NEDD4 ubiquitine ligase; this interaction might play a role in virus intracellular transport during entry. Protease cofactor: Homodimer; disulfide-linked. Interacts with the viral protease. Ref.5 Ref.6 Ref.7 Ref.8 Ref.10
Subcellular location	Pre-protein VI: Host nucleus Probable Ref.8. Endosome lysis protein: Virion. Host nucleus. Host cytoplasm. Note: Located inside the capsid underneath the 12 vertices. Present in around 360 copies per virion. Shuttles between host cytoplasm and nucleus. Ref.8
Induction	Expressed in the late phase of the viral replicative cycle.
Domain	N-terminal amphipathic alpha-helix domain is essential for the membrane lytic activity. Late-budding domains (L domains) are short sequence motifs essential for viral particle release. They can occur individually or in close proximity within structural proteins. They interacts with sorting cellular proteins of the multivesicular body (MVB) pathway. Most of these proteins are class E vacuolar protein sorting factors belonging to ESCRT-I, ESCRT-II or ESCRT-III complexes. Minor capsid protein 6 contains one L domain: a PPXY motif which binds to the WW domains of HECT (homologous to E6-AP C-terminus) E3 ubiquitin ligases, like NEDD4. In adenoviruses, this motif seems to play a role in microtubule-dependent intracellular trafficking toward the nucleus during virus entry into host cell and in suppression of DAXX-mediated repression of the immediate early E1A promoter.
Post-translational modification	Ubiquitinated by Nedd4 following partial capsid disassembly; which might play a role in intracellular virus movement during entry. Ref.10 Protease cofactor: Contains the major nuclear import and export signals. Proteolytically removed during virion maturation. The processing of the C-terminus turns the precursor into a mature viral structural protein and abrogates its ability to promote hexon import and act as a potential scaffold protein.
Miscellaneous	All late proteins expressed from the major late promoter are produced by alternative splicing and alternative polyadenylation of the same gene giving rise to non-overlapping ORFs. A leader sequence is present in the N-terminus of all these mRNAs and is recognized by the viral shutoff protein to provide expression although conventional translation via ribosome scanning from the cap has been shut off in the host cell.
Sequence similarities	Belongs to the adenoviridae protein VI family.

Ontologies

Keywords
Biological process	Cytoplasmic inwards viral transport Host-virus interaction Microtubular inwards viral transport Viral penetration into host cytoplasm Viral penetration via lysis of host organellar membrane Virus entry into host cell
Cellular component	Host cytoplasm Host nucleus Virion
Developmental stage	Late protein
Molecular function	Capsid protein Viral capsid scaffolding protein
PTM	Disulfide bond Phosphoprotein Ubl conjugation
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	viral entry into host cell Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	host cell cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell host cell nucleus Inferred from electronic annotation. Source: UniProtKB-SubCell viral capsid Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 250

250

Pre-protein VI

PRO_0000421078

Propeptide

1 – 33

33

PRO_0000036543

Chain

34 – 239

206

Endosome lysis protein

PRO_0000036544

Peptide

240 – 250

11

Protease cofactor

PRO_0000036545

Regions

Region

34 – 54

21

Amphipathic alpha-helix essential for membrane lytic activity

Region

48 – 74

27

Interaction with hexon protein

Region

105 – 225

121

Disordered Potential

Region

233 – 239

7

Interaction with hexon protein

Region

240 – 250

11

Binds to importin alpha/beta, involved in hexon nuclear import

Motif

67 – 76

10

Nuclear export signal By similarity

Motif

131 – 135

5

Nuclear localization signal Potential

Motif

148 – 151

4

PPXY motif By similarity

Motif

231 – 242

12

Nuclear export signal By similarity

Motif

245 – 248

4

Nuclear localization signal Potential

Sites

Site

33 – 34

2

Cleavage; by viral protease

Site

239 – 240

2

Cleavage; by viral protease

Amino acid modifications

Modified residue

124

1

Phosphoserine; by host Ref.2

Modified residue

143

1

Phosphothreonine; by host Ref.2

Disulfide bond

249

Interchain (with C-104 in Adenovirus protease) Ref.7

Experimental info

Mutagenesis

40

1

L → Q: Impaired endosome penetration and reduces infectivity. Ref.12

Mutagenesis

48

1

G → C: Decreased infectivity and endosomal membrane disruption activity. Ref.14

Secondary structure

1

.

.

.

250

Helix Strand Turn

Details...

Beta strand

243 – 249

7

Sequences

	Sequence		Length	Mass (Da)
	P03274 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: 4CACF18014647328	FASTA	250	27,014
	10 20 30 40 50 60 MEDINFASLA PRHGSRPFMG NWQDIGTSNM SGGAFSWGSL WSGIKNFGST IKNYGSKAWN 70 80 90 100 110 120 SSTGQMLRDK LKEQNFQQKV VDGLASGISG VVDLANQAVQ NKINSKLDPR PPVEEPPPAV 130 140 150 160 170 180 ETVSPEGRGE KRPRPDREET LVTQIDEPPS YEEALKQGLP TTRPIAPMAT GVLGQHTPVT 190 200 210 220 230 240 LDLPPPADTQ QKPVLPGPSA VVVTRPSRAS LRRAASGPRS MRPVASGNWQ STLNSIVGLG 250 VQSLKRRRCF

References

[1]	"Gene and mRNA for precursor polypeptide VI from adenovirus type 2." Akusjaervi G., Persson H. J. Virol. 38:469-482(1981) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"The phosphoproteome of the adenovirus type 2 virion." Bergstrom Lind S., Artemenko K.A., Elfineh L., Zhao Y., Bergquist J., Pettersson U. Virology 433:253-261(2012) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 107-128 AND 138-156, PHOSPHORYLATION AT SER-124 AND THR-143.
[3]	"Nucleic acid-binding properties of adenovirus structural polypeptides." Russell W.C., Precious B. J. Gen. Virol. 63:69-79(1982) [PubMed] [Europe PMC] [Abstract] Cited for: DNA-BINDING. Strain: Human adenovirus C serotype 5.
[4]	"The adenovirus protease is activated by a virus-coded disulphide-linked peptide." Webster A., Hay R.T., Kemp G. Cell 72:97-104(1993) [PubMed] [Europe PMC] [Abstract] Cited for: CHARACTERIZATION OF PROTEASE COFACTOR.
[5]	"Adenovirus protein-protein interactions: molecular parameters governing the binding of protein VI to hexon and the activation of the adenovirus 23K protease." Matthews D.A., Russell W.C. J. Gen. Virol. 76:1959-1969(1995) [PubMed] [Europe PMC] [Abstract] Cited for: INTERACTION OF PRE-PROTEIN VI WITH HEXON PROTEIN.
[6]	"Interaction of the human adenovirus proteinase with its 11-amino acid cofactor pVIc." Baniecki M.L., McGrath W.J., McWhirter S.M., Li C., Toledo D.L., Pellicena P., Barnard D.L., Thorn K.S., Mangel W.F. Biochemistry 40:12349-12356(2001) [PubMed] [Europe PMC] [Abstract] Cited for: INTERACTION OF PROTEASE COFACTOR WITH VIRAL PROTEASE.
[7]	"In the virion, the 11-amino-acid peptide cofactor pVIc is covalently linked to the adenovirus proteinase." McGrath W.J., Aherne K.S., Mangel W.F. Virology 296:234-240(2002) [PubMed] [Europe PMC] [Abstract] Cited for: INTERCHAIN DISULFIDE BOND WITH VIRAL PROTEASE.
[8]	"Switch from capsid protein import to adenovirus assembly by cleavage of nuclear transport signals." Wodrich H., Guan T., Cingolani G., Von Seggern D., Nemerow G., Gerace L. EMBO J. 22:6245-6255(2003) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION, SUBCELLULAR LOCATION OF PRE-PROTEIN VI, NUCLEAR LOCALIZATION SIGNALS, NUCLEAR EXPORT SIGNALS, INTERACTION OF PRE-PROTEIN VI WITH IMPORTIN ALPHA/BETA, INTERACTION OF PRE-PROTEIN VI WITH HEXON PROTEIN. Strain: Human adenovirus C serotype 5.
[9]	"Adenovirus protein VI mediates membrane disruption following capsid disassembly." Wiethoff C.M., Wodrich H., Gerace L., Nemerow G.R. J. Virol. 79:1992-2000(2005) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF ENDOSOME LYSIS PROTEIN. Strain: Human adenovirus C serotype 5.
[10]	"A capsid-encoded PPxY-motif facilitates adenovirus entry." Wodrich H., Henaff D., Jammart B., Segura-Morales C., Seelmeir S., Coux O., Ruzsics Z., Wiethoff C.M., Kremer E.J. PLoS Pathog. 6:E1000808-E1000808(2010) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION, UBIQUITINATION, INTERACTION WITH HOST NEDD4. Strain: Human adenovirus C serotype 5.
[11]	"An N-terminal domain of adenovirus protein VI fragments membranes by inducing positive membrane curvature." Maier O., Galan D.L., Wodrich H., Wiethoff C.M. Virology 402:11-19(2010) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF ENDOSOME LYSIS PROTEIN. Strain: Human adenovirus C serotype 5.
[12]	"Functional genetic and biophysical analyses of membrane disruption by human adenovirus." Moyer C.L., Wiethoff C.M., Maier O., Smith J.G., Nemerow G.R. J. Virol. 85:2631-2641(2011) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF ENDOSOME LYSIS PROTEIN, MUTAGENESIS OF LEU-40. Strain: Human adenovirus C serotype 5.
[13]	"Drifting motions of the adenovirus receptor CAR and immobile integrins initiate virus uncoating and membrane lytic protein exposure." Burckhardt C.J., Suomalainen M., Schoenenberger P., Boucke K., Hemmi S., Greber U.F. Cell Host Microbe 10:105-117(2011) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF ENDOSOME LYSIS PROTEIN.
[14]	"Disulfide-bond formation by a single cysteine mutation in adenovirus protein VI impairs capsid release and membrane lysis." Moyer C.L., Nemerow G.R. Virology 428:41-47(2012) [PubMed] [Europe PMC] [Abstract] Cited for: CHARACTERIZATION OF ENDOSOME LYSIS PROTEIN, MUTAGENESIS OF GLY-48. Strain: Human adenovirus C serotype 5.
[15]	"Latest insights on adenovirus structure and assembly." San Martin C. Viruses 4:847-877(2012) [PubMed] [Europe PMC] [Abstract] Cited for: REVIEW.
[16]	"Crystal structure of the human adenovirus proteinase with its 11 amino acid cofactor." Ding J., McGrath W.J., Sweet R.M., Mangel W.F. EMBO J. 15:1778-1783(1996) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.6 ANGSTROMS) OF 240-250 IN COMPLEX WITH VIRAL PROTEASE.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

J01917 Genomic DNA. Translation: AAA92214.1.

PIR

Q5ADB2. A03844.

RefSeq

AP_000174.1. AC_000007.1.
NP_040524.1. NC_001405.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1AVP	X-ray	2.60	B	240-250	[»]

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

GeneID

2652998.

Phylogenomic databases

ProtClustDB

CLSP2513899.

Family and domain databases

InterPro

IPR004243. McpVI.
[Graphical view]

Pfam

PF02993. MCPVI. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

P03274.

PMAP-CutDB

P03274.

Entry information

Entry name

CAP6_ADE02

Accession

Primary (citable) accession number: P03274

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	July 21, 1986
Last modified:	May 1, 2013
This is version 75 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program