Strain
Human_SARS_AY595412
(Region: China; Strain: SARS coronavirus LLJ-2004, complete genome.; Date: 2004)
Gene
3a
Description
Annotated in NCBI,
3a
Location
GenBank Accession
Full name
Protein 3a
Alternative Name
Accessory protein 3a
Protein U274
Protein X1
Protein U274
Protein X1
Sequence
CDS
ATGGATTTGTTTATGAGATTTTTTACTCTTGAATCAATTACTGCACAGCCAGTAAAAATTGACAATGCTTCTCCTGCAAGTACTGTTCATGCTACAGCAACGATACCGCTACAAGCCTCACTCCCTTTCGGATGGCTTGTTATTGGCGTTGCATTTCTTGCTGTTTTTCAGAGCGCTACCAAAATAATTGCGCTCAATAAAAGATGGCAGCTAGCCCTTTATAAGGGCTTCCAGTTCATTTGCAATTTACTGCTGCTATTTGTTACCATCTATTCACATCTTTTGCTTGTCGCTGCAGGTATGGAGGCGCAATTTTTGTACCTCTATGCCTTGATATATTTTCTACAATGCATCAACGCATGTAGAATTATTATGAGATGTTGGCTTTGTTGGAAGTGCAAATCCAAGAACCCATTACTTTATGATGCCAACTACTTTGTTTGCTGGCACACACATAACTATGACTACTGTATACCATATAACAGTGTCACAGATACAATTGTCGTTACTGAAGGTGACGGCATTTCAACACCAAAACTCAAAGAAGACTACCAAATTGGTGGTTATTCTGAGGATAGGCACTCAGGTGTTAAAGACTATGTCGTTGTACATGGCTATTTCACCGAAGTTTACTACCAGCTTGAGTCTACACAAATTACTACAGACACTGGTATTGAAAATGCTACATTCTTCATCTTTAACAAGCTTGTTAAAGATCCACCGAATGTGCAAATACACACAATCGACGGCTCTTCAGGAGTTGCTAATCCAGCAATGGATCCAATTTATGATGAGCCGACGACGACTACTAGCGTGCCTTTGTAA
Protein
MDLFMRFFTLESITAQPVKIDNASPASTVHATATIPLQASLPFGWLVIGVAFLAVFQSATKIIALNKRWQLALYKGFQFICNLLLLFVTIYSHLLLVAAGMEAQFLYLYALIYFLQCINACRIIMRCWLCWKCKSKNPLLYDANYFVCWHTHNYDYCIPYNSVTDTIVVTEGDGISTPKLKEDYQIGGYSEDRHSGVKDYVVVHGYFTEVYYQLESTQITTDTGIENATFFIFNKLVKDPPNVQIHTIDGSSGVANPAMDPIYDEPTTTTSVPL
Summary
Function
Forms homotetrameric potassium sensitive ion channels (viroporin) and may modulate virus release. Up-regulates expression of fibrinogen subunits FGA, FGB and FGG in host lung epithelial cells. Induces apoptosis in cell culture. Downregulates the type 1 interferon receptor by inducing serine phosphorylation within the IFN alpha-receptor subunit 1 (IFNAR1) degradation motif and increasing IFNAR1 ubiquitination.
Subunit
Homotetramer composed of two homodimers linked non covalently. Interacts with M, S and E proteins. Also interacts with the accessory protein 7a.
Keywords
Apoptosis
Glycoprotein
Host cell membrane
Host cytoplasm
Host Golgi apparatus
Host membrane
Host-virus interaction
Inhibition of host innate immune response by virus
Inhibition of host interferon receptors by virus
Inhibition of host interferon signaling pathway by virus
Ion channel
Ion transport
Membrane
Reference proteome
Secreted
Transmembrane
Transmembrane helix
Transport
Viral immunoevasion
Viral ion channel
Virion
Feature
chain Protein 3a
Uniprot
Pubmed
EMBL
Proteomes
PRIDE
Pfam
PF11289
APA3_viroporin
Interpro
IPR024407
SARS_coronavirus_Orf3/3a
ProteinModelPortal
Ontologies
KEGG
GO
GO:0044385 C:integral to membrane of host cell
GO:0039511 P:suppression by virus of host interferon receptor activity
GO:0020002 C:host cell plasma membrane
GO:0005216 F:ion channel activity
GO:0044178 C:host cell Golgi membrane
GO:0005576 C:extracellular region
GO:0051259 P:protein complex oligomerization
GO:0019012 C:virion
GO:0039707 P:pore formation by virus in membrane of host cell
GO:0016021 C:integral component of membrane
GO:0039502 P:suppression by virus of host type I interferon-mediated signaling pathway
GO:0039511 P:suppression by virus of host interferon receptor activity
GO:0020002 C:host cell plasma membrane
GO:0005216 F:ion channel activity
GO:0044178 C:host cell Golgi membrane
GO:0005576 C:extracellular region
GO:0051259 P:protein complex oligomerization
GO:0019012 C:virion
GO:0039707 P:pore formation by virus in membrane of host cell
GO:0016021 C:integral component of membrane
GO:0039502 P:suppression by virus of host type I interferon-mediated signaling pathway
Subcellular Location
From MSLVP
Host nucleus > host nucleolus. Host cytoplasm. Secreted.
From Uniprot
Virion
Host Golgi apparatus membrane
Host cell membrane
Secreted
Host cytoplasm
Host Golgi apparatus membrane
Host cell membrane
Secreted
Host cytoplasm
Topology
Length:
274
Number of predicted TMHs:
3
Exp number of AAs in TMHs:
65.0925700000001
Exp number, first 60 AAs:
20.24736
Total prob of N-in:
0.00291
POSSIBLE N-term signal
sequence
outside
1 - 33
TMhelix
34 - 56
inside
57 - 76
TMhelix
77 - 99
outside
100 - 102
TMhelix
103 - 125
inside
126 - 274
