P30211 (SIGM3_REOVJ) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Outer capsid protein sigma-3
Short name=Sigma3

Gene names

Name:

S4

Organism

Reovirus type 2 (strain D5/Jones) (T2J) (Mammalian orthoreovirus 2) [Complete proteome]

Taxonomic identifier

10885 [NCBI]

Taxonomic lineage

Viruses › dsRNA viruses › Reoviridae › Spinareovirinae › Orthoreovirus › Mammalian orthoreovirus › Mammalian orthoreovirus 2

Virus host

Mammalia [TaxID: 40674]

Protein attributes

Sequence length	365 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Stimulates translation by blocking the activation of the dsRNA-dependent protein kinase EIF2AK2/PKR, thereby inhibiting the host interferon response. Sigma3 prevents the activation of EIF2AK2 by competing with the kinase for dsRNA-binding By similarity. The viral outer shell polypeptides, of which sigma-3 is one, impose structural constraints that prevent elongation of nascent transcripts by the RNA-dependent RNA polymerase lambda-3 By similarity.
Subunit structure	Heterohexamer of three sigma-3 and three Mu-1 proteins. The RNA-binding form is probably a homodimer By similarity.
Subcellular location	Virion By similarity. Note: Found in the outer capsid. Each subunit is positioned with the small lobe anchoring it to the protein mu1 on the surface of the virion, and the large lobe, the site of initial cleavages during entry-related proteolytic disassembly, protruding outwards By similarity.
Post-translational modification	Cleaved during virus the endosomal proteolytic disassembly of the outer capsid By similarity.
Sequence similarities	Belongs to the orthoreovirus sigma-3 protein family. Contains 1 CCHC-type zinc finger.

Ontologies

Keywords
Biological process	Host-virus interaction Inhibition of host PKR by virus Inhibition of host innate immune response by virus Inhibition of host interferon signaling pathway by virus Interferon antiviral system evasion Transcription Transcription regulation Translation regulation Viral immunoevasion
Cellular component	Virion
Domain	Zinc-finger
Ligand	Metal-binding RNA-binding Zinc
Molecular function	Capsid protein
Technical term	Complete proteome
Gene Ontology (GO)
Biological_process	regulation of transcription, DNA-dependent Inferred from electronic annotation. Source: UniProtKB-KW regulation of translation Inferred from electronic annotation. Source: UniProtKB-KW suppression by virus of host PKR activity Inferred from electronic annotation. Source: UniProtKB-KW suppression by virus of host type I interferon-mediated signaling pathway Inferred from electronic annotation. Source: UniProtKB-KW transcription, DNA-dependent Inferred from electronic annotation. Source: UniProtKB-KW viral infectious cycle Inferred from electronic annotation. Source: InterPro
Cellular_component	viral capsid Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	RNA binding Inferred from electronic annotation. Source: UniProtKB-KW metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW structural molecule activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 365	365	Outer capsid protein sigma-3		PRO_0000222753
Regions
	Zinc finger	51 – 73	23	CCHC-type By similarity

Sequences

	Sequence		Length	Mass (Da)
	P30211 [UniParc]. Last modified April 1, 1993. Version 1. Checksum: 574350AEDFE04478	FASTA	365	41,226
	10 20 30 40 50 60 MEVCLPNGHQ IVDWINNAFE GRVSIYSAQQ GWDKTISAQP DMMVCGGAVV CMHCLGVVGS 70 80 90 100 110 120 LQRKLKHLPH HKCNQQLRQQ DYVDVQFADR VTAHWKRGML SFVSQMHAIM NDVTPEELER 130 140 150 160 170 180 VRTDGGSLAE LNWLQVDPGS MFRSIHSSWT DPLQVVEDLD TQLDRYWTAL NLMIDSSDLV 190 200 210 220 230 240 PNFMMRDPSH AFNGVKLEGE ARQTQFSRTF DSRSNLEWGV MIYDYSELER DPLKGRAYRK 250 260 270 280 290 300 EVVTPARDFG HFGLSHYSRA TTPILGKMPA VFSGMLTGNC KMYPFIKGTA KLRTVKKLVD 310 320 330 340 350 360 AVNHTWGSEK IRYALGPGGM TGWYNRTMQQ APIVLTPAAL TMFPDMTKFG DLQYPIMIGD PAVLG

References

[1]	"Translational effects and sequence comparisons of the three serotypes of the reovirus S4 gene." Seliger L.S., Giantini M., Shatkin A.J. Virology 187:202-210(1992) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	X60066 mRNA. Translation: CAA42670.1.
PIR	MNXRSJ. B42192.
3D structure databases
ProteinModelPortal	P30211.
SMR	P30211. Positions 1-365.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
InterPro	IPR000153. Reo_capsid_sigma3. IPR023634. Reovirus_capsid_sigma-3_dom. [Graphical view]
Pfam	PF00979. Reovirus_cap. 1 hit. [Graphical view]
SUPFAM	SSF64465. Reovirus_cap. 1 hit.
PROSITE	PS50158. ZF_CCHC. False negative. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

SIGM3_REOVJ

Accession

Primary (citable) accession number: P30211

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1993
Last sequence update:	April 1, 1993
Last modified:	April 3, 2013
This is version 59 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program