NCBI Accession #
NP_181532.2
NCBI GenBank Nucleotide #
NM_129561.4
NCBI Official Full Name
nuclear RNA polymerase D1B
NCBI Official Symbol
NRPD1B
NCBI Official Synonym Symbols
ATNRPD1B; DEFECTIVE IN MERISTEM SILENCING 5; DMS5; DRD3; NRPE1; nuclear RNA polymerase D1B; T28M21.19; T28M21_19
NCBI Protein Information
nuclear RNA polymerase D1B
NCBI Summary
Encodes the unique largest subunit of nuclear DNA-dependent RNA polymerase V; homologous to budding yeast RPB1 and the E. coli RNA polymerase beta prime subunit. Required for normal RNA-directed DNA methylation at non-CG methylation sites and transgene silencing.
UniProt Synonym Gene Names
DMS5; DRD3; NRPD1b; RMD1; RPE1; AtNRPD1b; Nuclear RNA polymerase D 1b; Nuclear RNA polymerase E 1; POL IV 1
UniProt Protein Name
DNA-directed RNA polymerase V subunit 1
UniProt Synonym Protein Names
DNA-directed RNA polymerase D subunit 1b; AtNRPD1b; Nuclear RNA polymerase D 1b; DNA-directed RNA polymerase E subunit 1 (EC:2.7.7.6); Nuclear RNA polymerase E 1; Protein DEFECTIVE IN MERISTEM SILENCING 5; Protein DEFECTIVE IN RNA-DIRECTED DNA METHYLATION 3; Protein RNA-DIRECTED DNA METHYLATION DEFECTIVE 1; RNA polymerase IV subunit 1; POL IV 1
UniProt Primary Accession #
Q5D869
UniProt Secondary Accession #
O04206; O04207; Q1L5X4
UniProt Related Accession #
Q5D869
UniProt Comments
DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic component of RNA polymerase V involved in RNA-directed DNA methylation-dependent (RdDM) silencing of endogenous repeated sequences, including transposable elements. Also required for full erasure of methylation when the RNA trigger is withdrawn. Seems also involved in the synthesis of short-interfering RNAs (siRNA). Essential component of a self-reinforcing loop coupling de novo DNA methylation to siRNA production. Involved in the maintenance of post-transcriptional RNA silencing.