P03383 (ENV_HTLV2) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Envelope glycoprotein gp63

Alternative name(s):
Env polyprotein

Cleaved into the following 2 chains:

1. Surface protein
   Short name=SU
   Alternative name(s):
   Glycoprotein 46
   Short name=gp46
2. Transmembrane protein
   Short name=TM
   Alternative name(s):
   Glycoprotein 21
   Short name=gp21

Gene names

Name:

env

Organism

Human T-cell leukemia virus 2 (HTLV-2) [Reference proteome]

Taxonomic identifier

11909 [NCBI]

Taxonomic lineage

Viruses › Retro-transcribing viruses › Retroviridae › Orthoretrovirinae › Deltaretrovirus › Primate T-lymphotropic virus 2

Virus host

Homo sapiens (Human) [TaxID: 9606]

Protein attributes

Sequence length	486 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	The surface protein (SU) attaches the virus to the host cell by binding to its receptor. This interaction triggers the refolding of the transmembrane protein (TM) and is thought to activate its fusogenic potential by unmasking its fusion peptide. Fusion occurs at the host cell plasma membrane By similarity. The transmembrane protein (TM) acts as a class I viral fusion protein. Under the current model, the protein has at least 3 conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes. Membranes fusion leads to delivery of the nucleocapsid into the cytoplasm By similarity.
Subunit structure	The mature envelope protein (Env) consists of a trimer of SU-TM heterodimers attached by a labile interchain disulfide bond By similarity.
Subcellular location	Transmembrane protein: Virion membrane; Single-pass type I membrane protein By similarity. Host cell membrane; Single-pass type I membrane protein By similarity. Note: It is probably concentrated at the site of budding and incorporated into the virions possibly by contacts between the cytoplasmic tail of Env and the N-terminus of Gag By similarity. Surface protein: Virion membrane; Peripheral membrane protein By similarity. Host cell membrane; Peripheral membrane protein By similarity. Note: The surface protein is not anchored to the viral envelope, but associates with the extravirion surface through its binding to TM. It is probably concentrated at the site of budding and incorporated into the virions possibly by contacts between the cytoplasmic tail of Env and the N-terminus of Gag By similarity.
Domain	The 17 amino acids long immunosuppressive region is present in many retroviral envelope proteins. Synthetic peptides derived from this relatively conserved sequence inhibit immune function in vitro and in vivo By similarity.
Post-translational modification	Specific enzymatic cleavages in vivo yield mature proteins. Envelope glycoproteins are synthesized as a inactive precursor that is N-glycosylated and processed likely by host cell furin or by a furin-like protease in the Golgi to yield the mature SU and TM proteins. The cleavage site between SU and TM requires the minimal sequence [KR]-X-[KR]-R By similarity. The CXXC motif is highly conserved across a broad range of retroviral envelope proteins. It is thought to participate in the formation of a labile disulfide bond possibly with the CX6CC motif present in the transmembrane protein. Isomerization of the intersubunit disulfide bond to an SU intrachain disulfide bond is thought to occur upon receptor recognition in order to allow membrane fusion By similarity. The transmembrane protein is palmitoylated By similarity.

Ontologies

Keywords
Biological process	Fusion of virus membrane with host cell membrane Fusion of virus membrane with host membrane Host-virus interaction Viral attachment to host cell Viral penetration into host cytoplasm Virus entry into host cell
Cellular component	Host cell membrane Host membrane Membrane Viral envelope protein Virion
Domain	Coiled coil Signal Transmembrane Transmembrane helix
PTM	Cleavage on pair of basic residues Disulfide bond Glycoprotein Lipoprotein Palmitate
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	viral attachment to host cell Inferred from electronic annotation. Source: UniProtKB-KW viral entry into host cell via membrane fusion with the plasma membrane Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	host cell plasma membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW viral envelope Inferred from electronic annotation. Source: UniProtKB-KW virion membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 18	18	Potential
	Chain	19 – 486	468	Envelope glycoprotein gp63		PRO_0000239544
	Chain	19 – 308	290	Surface protein By similarity		PRO_0000038761
	Chain	309 – 486	178	Transmembrane protein By similarity		PRO_0000038762
Regions
	Topological domain	19 – 438	420	Extracellular Potential
	Transmembrane	439 – 459	21	Helical; Potential
	Topological domain	460 – 486	27	Cytoplasmic Potential
	Region	309 – 329	21	Fusion peptide Potential
	Region	372 – 388	17	Immunosuppression By similarity
	Coiled coil	337 – 383	47	Potential
	Coiled coil	393 – 425	33	Potential
	Motif	221 – 224	4	CXXC
	Motif	389 – 397	9	CX6CC
Sites
	Site	308 – 309	2	Cleavage; by host furin
Amino acid modifications
	Lipidation	458	1	S-palmitoyl cysteine; by host By similarity
	Glycosylation	136	1	N-linked (GlcNAc...); by host Potential
	Glycosylation	218	1	N-linked (GlcNAc...); by host Potential
	Glycosylation	240	1	N-linked (GlcNAc...); by host Potential
	Glycosylation	286	1	N-linked (GlcNAc...); by host Potential
	Glycosylation	400	1	N-linked (GlcNAc...); by host Potential
	Disulfide bond	221 ↔ 397		Interchain (between SU and TM chains, or C-224 with C-397); alternate By similarity
	Disulfide bond	221 ↔ 224		Alternate By similarity
	Disulfide bond	389 ↔ 396		By similarity
Experimental info
	Sequence conflict	27	1	I → V in AAA45410. Ref.2
	Sequence conflict	56	1	D → H in AAA45410. Ref.2
	Sequence conflict	115	1	A → S in AAA45410. Ref.2
	Sequence conflict	118 – 119	2	SA → CP in AAA45410. Ref.2
	Sequence conflict	267	1	F → P Ref.2
	Sequence conflict	302	1	P → L in AAA45410. Ref.2
	Sequence conflict	318	1	S → P in AAA45410. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	P03383 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: 60D70B9CE8986CE5	FASTA	486	54,158
	10 20 30 40 50 60 MGNVFFLLLF SLTHFPLAQQ SRCTLTIGIS SYHSSPCSPT QPVCTWNLDL NSLTTDQRLH 70 80 90 100 110 120 PPCPNLITYS GFHKTYSLYL FPHWIKKPNR QGLGYYSPSY NDPCSLQCPY LGCQAWTSAY 130 140 150 160 170 180 TGPVSSPSWK FHSDVNFTQE VSQVSLRLHF SKCGSSMTLL VDAPGYDPLW FITSEPTQPP 190 200 210 220 230 240 PTSPPLVHDS DLEHVLTPST SWTTKILKFI QLTLQSTNYS CMVCVDRSSL SSWHVLYTPN 250 260 270 280 290 300 ISIPQQTSSR TILFPSLALP APPSQPFPWT HCYQPRLQAI TTDNCNNSII LPPFSLAPVP 310 320 330 340 350 360 PPATRRRRAV PIAVWLVSAL AAGTGIAGGV TGSLSLASSK SLLLEVDKDI SHLTQAIVKN 370 380 390 400 410 420 HQNILRVAQY AAQNRRGLDL LFWEQGGLCK AIQEQCCFLN ISNTHVSVLQ ERPPLEKRVI 430 440 450 460 470 480 TGWGLNWDLG LSQWAREALQ TGITILALLL LVILFGPCIL RQIQALPQRL QNRHNQYSLI NPETML

References

[1]	"Complete nucleotide sequence of an infectious clone of human T-cell leukemia virus type II: an open reading frame for the protease gene." Shimotohno K., Takahashi Y., Shimizu N., Gojobori T., Golde D.W., Chen I.S.Y., Miwa M., Sugimura T. Proc. Natl. Acad. Sci. U.S.A. 82:3101-3105(1985) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Sequence of the envelope glycoprotein gene of type II human T lymphotropic virus." Sodroski J., Patarca R., Perkins D., Briggs D., Lee T.-H., Essex M., Coligan J., Wong-Staal F., Gallo R.C., Haseltine W.A. Science 225:421-424(1984) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA].
[3]	"Processing of the HTLV-II envelope precursor glycoprotein gp62 by furin is essential for cell fusion activity." Hasegawa H., Tatsumi M., Ogawa-Goto K., Takahashi H., Kojima A., Iwasaki T., Kurata T., Sata T., Takeuchi T., Sheehy N., Sawa H., Nagashima K., Hall W.W. AIDS Res. Hum. Retroviruses 18:1253-1260(2002) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEOLYTIC PROCESSING OF POLYPROTEIN BY FURIN.

Cross-references

Sequence databases
EMBL GenBank DDBJ	M10060 Genomic DNA. Translation: AAB59887.1. K02024 Genomic RNA. Translation: AAA45410.1.
PIR	VCLJT2. A03980. VCLJH2. A03981.
RefSeq	NP_041006.1. NC_001488.1.
3D structure databases
ProteinModelPortal	P03383.
SMR	P03383. Positions 334-416.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
InterPro	IPR018154. TLV/ENV_coat_polyprotein. [Graphical view]
PANTHER	PTHR10424. PTHR10424. 1 hit.
Pfam	PF00429. TLV_coat. 2 hits. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

ENV_HTLV2

Accession

Primary (citable) accession number: P03383
Secondary accession number(s): P03382

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	July 21, 1986
Last modified:	April 3, 2013
This is version 90 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program