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HAMAP rule MF_04128

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General rule information [?]

Accession MF_04128
Dates 28-MAR-2018 (Created)
30-JAN-2024 (Last updated, Version 12)
Name Rota_VP3_A
Scope(s) Viruses
Template(s) A2T3S5 (VP3_ROTSH); Q6WAT6 (VP3_ROTBU); [ Recover all ]
Triggered by HAMAP; MF_04128 (Get profile general information and statistics)

Propagated annotation [?]

Identifier, protein and gene names [?]

Identifier VP3
Protein name RecName: Full=Protein VP3;
RecName: Full=2',5'-phosphodiesterase;
RecName: Full=mRNA guanylyltransferase;
RecName: Full=mRNA (guanine-N(7))-methyltransferase;

Comments [?]

FUNCTIONMultifunctional enzyme involved in mRNA capping. Catalyzes the formation of the 5' cap structure on the viral plus-strand transcripts. Specifically binds to GTP and displays guanylyltransferase and methyltransferase activities. Has affinity for ssRNA but not for dsRNA. Capping activity is non-specific and caps RNAs that initiate with either a G or an A residue. Together with VP1 polymerase, forms a VP1-VP3 complex positioned near the channels situated at each of the five-fold vertices of the core. Following infection, the outermost layer of the virus is lost, leaving a double-layered particle (DLP) made up of the core and VP6 shell. VP1 then catalyzes the transcription of fully conservative plus-strand genomic RNAs that are capped by VP3 and extruded through the DLP's channels into the cytoplasm where they function as mRNAs for translation of viral proteins. DLPs probably have an RNA triphosphatase activity as well, whereas open cores do not.
FUNCTIONCounteracts the host innate immune response thanks to its phosphodiesterase that degrades the 5'-triphosphorylated, 2'-5' linked adenylate oligomers produced by the host cell IFN-inducible 2',5'- oligoadenylate synthetase (OAS). The host RNaseL is therefore not activated.
DOMAINContains a bipartite N7-methyltransferase domain, a 2'-O- methyltransferase domain and a GTase/RTPase domain. The C-terminus contains a phosphodiesterase domain that degrades the 5'- triphosphorylated, 2'-5' linked adenylate oligomers produced by the host cell in response to IFN stimulation.
CATALYTIC ACTIVITY Reaction=a 5'-end diphospho-ribonucleoside in mRNA + GTP + H(+) = a 5'- end (5'-triphosphoguanosine)-ribonucleoside in mRNA + diphosphate; Xref=Rhea:RHEA:67012, Rhea:RHEA-COMP:17165, Rhea:RHEA-COMP:17166, ChEBI:CHEBI:15378, ChEBI:CHEBI:33019, ChEBI:CHEBI:37565, ChEBI:CHEBI:167616, ChEBI:CHEBI:167617; EC=;
CATALYTIC ACTIVITY Reaction=a 5'-end (5'-triphosphoguanosine)-ribonucleoside in mRNA + S- adenosyl-L-methionine = a 5'-end (N(7)-methyl 5'- triphosphoguanosine)-ribonucleoside in mRNA + S-adenosyl-L- homocysteine; Xref=Rhea:RHEA:67008, Rhea:RHEA-COMP:17166, Rhea:RHEA- COMP:17167, ChEBI:CHEBI:57856, ChEBI:CHEBI:59789, ChEBI:CHEBI:156461, ChEBI:CHEBI:167617; EC=;
CATALYTIC ACTIVITY Reaction=5'-triphosphoadenylyl-(2'->5')-adenylyl-(2'->5')-adenosine + 2 H2O = 2 AMP + ATP + 2 H(+); Xref=Rhea:RHEA:45964, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, ChEBI:CHEBI:67143, ChEBI:CHEBI:456215;
SUBUNITInteracts with VP1. Interacts with VP2.
SUBCELLULAR LOCATIONVirion. Note=Attached inside the inner capsid as a minor component. There are about 11 to 12 copies per virion.
SIMILARITYBelongs to the rotavirus VP3 family.

Keywords [?]

Gene Ontology [?]

GO:0019013; Cellular component:viral nucleocapsid
GO:0005525; Molecular function:GTP binding
GO:0004482; Molecular function:mRNA 5'-cap (guanine-N7-)-methyltransferase activity
GO:0004484; Molecular function:mRNA guanylyltransferase activity
GO:0003723; Molecular function:RNA binding
GO:0016032; Biological process:viral process

Cross-references [?]

PROSITE PS51589; SAM_MT56_VP3; 1;
Pfam PF06929; Rotavirus_VP3; 1;
PIRSF PIRSF004015; LigT_rotavirus; 1;

Features [?]

From: VP3_ROTSH (A2T3S5)
Key From To Description Tag Condition FTGroup
REGION 171 245 /note="N7-methyltransferase activity"
REGION 246 428 /note="2'-O-methyltransferase activity"
REGION 429 555 /note="N7-methyltransferase activity"
REGION 556 692 /note="GTase/RTPase activity"
REGION 693 Cter /note="2'-5'-phosphodiesterase activity"
ACT_SITE 718 718 /note="For 2'-5'-phosphodiesterase activity" H
ACT_SITE 720 720 /note="For 2'-5'-phosphodiesterase activity" T
ACT_SITE 797 797 /note="For 2'-5'-phosphodiesterase activity" H
ACT_SITE 799 799 /note="For 2'-5'-phosphodiesterase activity" T

Additional information [?]

Size range 690-840 amino acids
Related rules MF_04124
Fusion Nter: None Cter: None

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