P25950 (MCEL_RFVKA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
mRNA-capping enzyme catalytic subunit

Alternative name(s):
Virus termination factor large subunit
Short name=VTF large subunit
mRNA-capping enzyme 97 kDa subunit
mRNA-capping enzyme large subunit

Including the following 3 domains:

1. Polynucleotide 5'-triphosphatase
   EC=3.1.3.33
   Alternative name(s):
   mRNA 5'-triphosphatase
   Short name=TPase
2. mRNA guanylyltransferase
   EC=2.7.7.50
   Alternative name(s):
   GTP--RNA guanylyltransferase
   Short name=GTase
3. mRNA (guanine-N(7)-)-methyltransferase
   EC=2.1.1.56
   Alternative name(s):
   mRNA cap methyltransferase

Gene names

ORF Names:

D3R, s076R

Organism

Rabbit fibroma virus (strain Kasza) (RFV) (Shope fibroma virus (strain Kasza))

Taxonomic identifier

10272 [NCBI]

Taxonomic lineage

Viruses › dsDNA viruses, no RNA stage › Poxviridae › Chordopoxvirinae › Leporipoxvirus

Virus host

Oryctolagus cuniculus (Rabbit) [TaxID: 9986]

Protein attributes

Sequence length	836 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Catalytic subunit of the mRNA capping enzyme which catalyzes three enzymatic reactions: the 5' triphosphate end of the pre-mRNA is hydrolyzed to a diphosphate by RNA 5' triphosphatase; the diphosphate RNA end is capped with GMP by RNA guanylyltransferase and the GpppN cap is methylated by RNA (guanine-N7) methyltransferase. Heterodimeric mRNA capping enzyme catalyzes the linkage of a N7-methyl-guanosine moiety to the first transcribed nucleotide (cap 0 structure), whereas the polymerase associated VP39 is responsible for a second methylation at the 2'-O position of the ribose (cap 1 structure) By similarity. The heterodimeric enzyme is also involved in early viral gene transcription termination and intermediate viral gene transcription initiation. Early gene transcription termination requires the termination factor VTF, the DNA-dependent ATPase NPH-I and the Rap94 subunit of the viral RNA polymerase, as well as the presence of a specific termination motif. Binds, together with RAP94, to the termination motif 5'-UUUUUNU-3' in the nascent early mRNA By similarity.
Catalytic activity	A 5'-phosphopolynucleotide + H2O = a polynucleotide + phosphate. GTP + (5')pp-Pur-mRNA = diphosphate + G(5')ppp-Pur-mRNA. S-adenosyl-L-methionine + G(5')pppR-RNA = S-adenosyl-L-homocysteine + m7G(5')pppR-RNA.
Subunit structure	Heterodimer of a catalytic and a regulatory subunit. Intrinsic methyltransferase activity of the catalytic subunit is weak and needs to be stimulated 30- to 50-fold by the regulatory subunit, which is itself catalytically inert By similarity.
Subcellular location	Virion Probable. Note: All the enzymes and other proteins required to synthesize early mRNAs are packaged within the virion core along with the DNA genome.
Domain	The N-terminus contains the triphosphatase and guanylyltransferase domains, whereas the C-terminus contains the methyltransferase domain. The N-terminus is involved in binding to the temination motif 5'-UUUUUNU-3' in the nascent mRNA By similarity.
Sequence similarities	Belongs to the viral GTase family.

Ontologies

Keywords
Biological process	mRNA capping mRNA processing
Cellular component	Virion
Ligand	Metal-binding S-adenosyl-L-methionine
Molecular function	Hydrolase Methyltransferase Nucleotidyltransferase Transferase
Technical term	Complete proteome Multifunctional enzyme Reference proteome
Gene Ontology (GO)
Biological process	mRNA capping Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	virion Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	mRNA (guanine-N7-)-methyltransferase activity Inferred from electronic annotation. Source: EC mRNA guanylyltransferase activity Inferred from electronic annotation. Source: EC metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW polynucleotide 5'-phosphatase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 836	836	mRNA-capping enzyme catalytic subunit		PRO_0000210131
Regions
	Region	1 – 532	532	Triphosphatase-guanylyltransferase By similarity
	Region	533 – 836	304	Methyltransferase By similarity
Sites
	Active site	256	1	N6-GMP-lysine intermediate By similarity
	Metal binding	35	1	Catalytic; for RNA triphosphatase activity Potential
	Metal binding	37	1	Catalytic; for RNA triphosphatase activity Potential
	Metal binding	189	1	Catalytic; for RNA triphosphatase activity Potential
	Metal binding	191	1	Catalytic; for RNA triphosphatase activity Potential
	Site	74	1	Essential for RNA triphosphatase activity By similarity
	Site	104	1	Essential for RNA triphosphatase activity By similarity
	Site	123	1	Essential for RNA triphosphatase activity By similarity
	Site	156	1	Essential for RNA triphosphatase activity By similarity
	Site	158	1	Essential for RNA triphosphatase activity By similarity

Sequences

	Sequence		Length	Mass (Da)
	P25950 [UniParc]. Last modified May 1, 1992. Version 1. Checksum: 7375FDA548AE1730	FASTA	836	97,018
	10 20 30 40 50 60 MDDSKKKRGT DYIEELILLY EDVPNPVQTD DMNHEVELTF IQPPVITLST LLPFATSQES 70 80 90 100 110 120 YILFTVTNKG VKIRNRINLS KIHGLDLKNI QLVDSIDNII WEKKTLVKEH KIDSVALVKY 130 140 150 160 170 180 STEEKYIFLD YKKYLSAIKL ELVNVVQVKV KHVTVDFKFK YFLGSGAQAK SSLLHVLNHP 190 200 210 220 230 240 KSKPNPSLEF EIITTDEKID SASLRKELIA LFKLVFMASP SNIILDVVFK NPVQTILLKK 250 260 270 280 290 300 NELPGIDLTN LYVTTKTDGV GVLITVTNKG IYCFFTHLQY TIRYDTTFES NESVTLYGEA 310 320 330 340 350 360 VKQNNVWQIY LIKLITPKVS DRFKEKEYVE ERLQNICDRM TFKVKKYEGP FESHSEIIDL 370 380 390 400 410 420 LTTYLPSQPE GVVLFYSDQR NQPDYKIKLD NTTDHMINII YRYMSSEPVI FGENSTFLEY 430 440 450 460 470 480 KKFSDDKGFP KDYGTGKLML TDNVRYLNNI YCIAFTNVYE DVGIKNVVVP IKFISEFSAT 490 500 510 520 530 540 GELIKPRIDK TFKYLYKEYY GNQYQIVVAH IRDQNIKIGD VLDEDKLSDV GQHYANDKYR 550 560 570 580 590 600 LNPDVSYFTN KRTRGPLGIL SNYVKTLLIS LYCSKTFLDN SNKRKVLAID FGNGADLEKY 610 620 630 640 650 660 FYGEISSLVA TDPDKEAIGR CIERYNSLNS GIKSKYYKFD YIQETIRSVT YVSSVREVFF 670 680 690 700 710 720 FGKFDLVDWQ FAIHYSFHPK HYATVMNNLT ELTASGGKVL ITTMDGDLLS QLTDKKTFVI 730 740 750 760 770 780 HKNLPSSENY MSVEKIHEDQ ILVYNPSSMS RPMQEYIVKR VNLTKIFSEY GFELIDCVHF 790 800 810 820 830 DTIIERSKRF INSVSKMEER KSTKNFFELN REALKHEGTD IDDLLRYYIV YVFSKR

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Identification and DNA sequence of the large subunit of the capping enzyme from Shope fibroma virus." Upton C., Stuart D., McFadden G. Virology 183:773-777(1991) [PubMed: 1649507] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Sequence and analysis of a portion of the genomes of Shope fibroma virus and malignant rabbit fibroma virus that is important for viral replication in lymphocytes." Strayer D.S., Jerng H.H., O'Connor K. Virology 185:585-595(1991) [PubMed: 1660196] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]	"The complete genome sequence of shope (Rabbit) fibroma virus." Willer D.O., McFadden G., Evans D.H. Virology 264:319-343(1999) [PubMed: 10562495] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[4]	"Identification and DNA sequence of the Shope fibroma virus DNA topoisomerase gene." Upton C., Opgenorth A., Traktman P., McFadden G. Virology 176:439-447(1990) [PubMed: 2161144] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-97.
[5]	"Sequence and analysis of the BamHI 'D' fragment of Shope fibroma virus: comparison with similar regions of related poxviruses." Strayer D.S., Jerng H.H. Virus Res. 25:117-132(1992) [PubMed: 1329373] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 38-836.

Cross-references

Sequence databases
EMBL GenBank DDBJ	M63902 Genomic DNA. Translation: AAA47224.1. AF170722 Genomic DNA. Translation: AAF17958.1.
PIR	QQVZRA. A40478.
RefSeq	NP_051965.1. NC_001266.1.
3D structure databases
ProteinModelPortal	P25950.
SMR	P25950. Positions 537-836.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
GeneID	1486919.
Phylogenomic databases
ProtClustDB	CLSP2509789.
Family and domain databases
InterPro	IPR019602. mRNA_cap_ATPase/GuylTrfase_vir. IPR004971. Pox_MCEL. [Graphical view]
Pfam	PF10640. Pox_ATPase-GT. 1 hit. PF03291. Pox_MCEL. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

MCEL_RFVKA

Accession

Primary (citable) accession number: P25950
Secondary accession number(s): Q77PC1

Entry history

Integrated into UniProtKB/Swiss-Prot:	May 1, 1992
Last sequence update:	May 1, 1992
Last modified:	January 25, 2012
This is version 62 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program