Q83626 · Q83626_MEASF

Function

function

RNA-directed RNA polymerase that catalyzes the replication of viral genomic RNA. The template is composed of the viral RNA tightly encapsidated by the nucleoprotein (N). The replicase mode is dependent on intracellular N protein concentration. In this mode, the polymerase replicates the whole viral genome without recognizing transcriptional signals, and the replicated genome is not caped or polyadenylated.
RNA-directed RNA polymerase that catalyzes the transcription of viral mRNAs, their capping and polyadenylation. The template is composed of the viral RNA tightly encapsidated by the nucleoprotein (N). The viral polymerase binds to the genomic RNA at the 3' leader promoter, and transcribes subsequently all viral mRNAs with a decreasing efficiency. The first gene is the most transcribed, and the last the least transcribed. The viral phosphoprotein acts as a processivity factor. Capping is concommitant with initiation of mRNA transcription. Indeed, a GDP polyribonucleotidyl transferase (PRNTase) adds the cap structure when the nascent RNA chain length has reached few nucleotides. Ribose 2'-O methylation of viral mRNA cap precedes and facilitates subsequent guanine-N-7 methylation, both activities being carried by the viral polymerase. Polyadenylation of mRNAs occur by a stuttering mechanism at a slipery stop site present at the end viral genes. After finishing transcription of a mRNA, the polymerase can resume transcription of the downstream gene.

Catalytic activity

  • GTP + H2O = GDP + phosphate + H+
  • a 5'-end (5'-triphosphoguanosine)-(2'-O-methyladenylyl)-adenylyl-cytidylyl-adenosine in mRNA + S-adenosyl-L-methionine = a 5'-end (N7-methyl 5'-triphosphoguanosine)-(2'-O-methyladenylyl)-adenylyl-cytidylyl-adenosine in mRNA + S-adenosyl-L-homocysteine
  • a 5'-end (5'-triphosphoguanosine)-adenylyl-adenylyl-cytidylyl-adenosine in mRNA + 2 S-adenosyl-L-methionine = a 5'-end (N7-methyl 5'-triphosphoguanosine)-(2'-O-methyladenylyl)-adenylyl-cytidylyl-adenosine in mRNA + 2 S-adenosyl-L-homocysteine + H+
    EC:2.1.1.375 (UniProtKB | ENZYME | Rhea)
  • a 5'-end (5'-triphosphoguanosine)-adenylyl-adenylyl-cytidylyl-adenosine in mRNA + S-adenosyl-L-methionine = a 5'-end (5'-triphosphoguanosine)-(2'-O-methyladenylyl)-adenylyl-cytidylyl-adenosine in mRNA + S-adenosyl-L-homocysteine + H+
  • a 5'-end triphospho-adenylyl-adenylyl-cytidylyl-adenosine in mRNA + GDP + H+ = a 5'-end (5'-triphosphoguanosine)-adenylyl-adenylyl-cytidylyl-adenosine in mRNA + diphosphate
    EC:2.7.7.88 (UniProtKB | ENZYME | Rhea)
  • RNA(n) + a ribonucleoside 5'-triphosphate = RNA(n+1) + diphosphate
    EC:2.7.7.48 (UniProtKB | ENZYME | Rhea)

GO annotations

AspectTerm
Cellular Componentcytoplasm
Cellular Componenthost cell cytoplasm
Cellular Componentvirion component
Molecular FunctionATP binding
Molecular FunctionGTPase activity
Molecular FunctionmRNA 5'-cap (guanine-N7-)-methyltransferase activity
Molecular FunctionRNA-dependent RNA polymerase activity

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    RNA-directed RNA polymerase L
  • Short names
    Protein L
  • Alternative names
    • Large structural protein
    • Replicase
    • Transcriptase

Including 5 domains:

  • Recommended name
    RNA-directed RNA polymerase
  • EC number
  • Recommended name
    GTP phosphohydrolase
  • EC number
  • Recommended name
    GDP polyribonucleotidyltransferase
  • EC number
  • Alternative names
    • PRNTase
  • Recommended name
    mRNA (nucleoside-2'-O-)-methyltransferase
  • EC number
  • Short names
    N1-2'-O-MTase
  • Recommended name
    mRNA (guanine-N(7)-)-methyltransferase
  • Short names
    G-N7-MTase

Organism names

Accessions

  • Primary accession
    Q83626

Proteomes

Subcellular Location

Keywords

Interaction

Subunit

Interacts with the P protein.

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain656-840RdRp catalytic
Domain1755-1958Mononegavirus-type SAM-dependent 2'-O-MTase

Sequence similarities

Belongs to the paramyxovirus L protein family.

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    2,183
  • Mass (Da)
    247,595
  • Last updated
    1996-11-01 v1
  • Checksum
    CE3E40FB6297DA6A
MDSLSVNQILYPEVHLDSPIVTNKIVAILEYARVPHAYSLEDPTLCQNIKHRLKNGFSNQMIINNVEVGNVIKSKLRSYPAHSHIPYPNCNQDLFNIEDKESTRKIRELLKKGNSLYSKVSDKVFQCLRDTNSRLGLGSELREDIKEKVINLGVYMHSSQWFEPFLFWFTVKTEMRSVIKSQTHTCHRRRHTPVFFTGSSVELLISRDLVAIISKESQHVYYLTFELVLMYCDVIEGRLMTETAMTIDARYTELLGRVRYMWKLIDGFFPALGNPTYQIVAMLEPLSLAYLQLRDITVELRGAFLNHCFTEIHDVLDQNGFSDEGTYHELIEALDYIFITDDIHLTGEIFSFFRSFGHPRLEAVTAAENVRKYMNQPKVIVYETLMKGHAIFCGIIINGYRDRHGGSWPPLTLPLHAADTIRNAQASGDGLTHEQCVDNWKSFAGVKFGCFMPLSLDSDLTMYLKDKALAALQREWDSVYPKEFLRYDPPKGTGSRRLVDVFLNDSSFDPYDVIMYVVSGAYLHDPEFNLSYSLKEKEIKETGRLFAKMTYKMRACQVIAENLISNGIGKYFKDNGMAKDEHDLTKALHTLAVSGVPKDLKESHRGGPVLKTYSRSPVHTSTRNVRAAKGFIGFPQVIRQDQDTDHPENMEAYETVSAFITTDLKKYCLNWRYETISLFAQRLNEIYGLPSFFQWLHKRLETSVLYVSDPHCPPDLDAHIPLYKVPNDQIFIKYPMGGIEGYCQKLWTISTIPYLYLAAYESGVRIASLVQGDNQTIAVTKRVPSTWPYNLKKREAARVTRDYFVILRQRLHDIGHHLKANETIVSSHFFVYSKGIYYDGLLVSQSLKSIARCVFWSETIVDETRAACSNIATTMAKSIERGYDRYLAYSLNVLKVIQQILISLGFTINSTMTRDVVIPLLTNNDLLIRMALLPAPIGGMNYLNMSRLFVRNIGDPVTSSIADLKRMILASLMPEETLHQVMTQQPGDSSFLDWASDPYSANLVCVQSITRLLKNITARFVLIHSPNPMLKGLFHDDSKEEDEGLAAFLMDRHIIVPRAAHEILDHSVTGARESIAGMLDTTKGLIRASMRKGGLTSRVITRLSNYDYEQFRAGMVLLTGRKRNVLIDKESCSVQLARALRSHMWARLARGRPIYGLEVPDVLESMRGHLIRRHETCVICECGSVNYGWFFVPSGCQLDDIDKETSSLRVPYIGSTTDERTDMKLAFVRAPSRSLRSAVRIATVYSWAYGDDDSSWNEAWLLARQRANVSLEELRVITPISTSTNLAHRLRDRSTQVKYSGTSLVRVARYTTISNDNLSFVISDKKVDTNFIYQQGMLLGLGVLETLFRLEKDTGSSNTVLHLHVETDCCVIPMIDHPRIPSSRKLELRAELCTNPLIYDNAPLIDRDATRLYTQSHRRHLVEFVTWSTPQLYHILAKSTALSMIDLVTKFEKDHMNEISALIGDDDINSFITEFLLIEPRLFTIYLGQCAAINWAFDVHYHRPSGKYQMGELLSSFLSRMSKGVFKVLVNALSHPKIYKKFWHCGIIEPIHGPSLDAQNLHTTVCNMVYTCYMTYLDLLLNEELEEFTFLLCESDEDVVPDRFDNIQAKHLCVLADLYCQPGTCPPIQGLRPVEKCAVLTDHIKAEAMLSPAGSSWNINPIIVDHYSCSLTYLRRGSIKQIRLRVDPGFIFDALAEVNVSQPKIGSNNISNMSIKAFRPPHDDVAKLLKDINTSKHNLPISGGNLANYEIHAFRRIGLNSSACYKAVEISTLIRRCLEPGEDGLFLGEGSGSMLITYKEILKLSKCFYNSGVSANSRSGQRELAPYPSEVGLVEHRMGVGNIVKVLFNGRPEVTWVGSVDCFNFIVSNIPTSSVGFIHSDIETLPDKDTIEKLEELAAILSMALLLGKIGSILVIKLMPFSGDFVQGFISYVGSHYREVNLVYPRYSNFISTESYLVMTDLKANRLMNPEKIKQQIIESSVRTSPGLIGHILSIKQLSCIQAIVGDAVSRGDINPTLKKLTPIEQVLINCGLAINGPKLCKELIHHDVASGQDGLLNSILILYRELARFKDNQRSQQGMFHAYPVLVSSRQRELISRITRKFWGHILLYSGNRKLINKFIQNLKSGYLILDLHQNIFVKNLSKSEKQIIMTGGLKREWVFKVTVKETKEWYKLVGYSALIKD

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
Z66517
EMBL· GenBank· DDBJ
CAA91370.1
EMBL· GenBank· DDBJ
Genomic RNA

Similar Proteins

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