RNA Polymerase III, DNA Directed Polypeptide B (POLR3B)

POLR3B is a 1,133 amino acid protein that localizes to the nucleus and belongs to the RNA polymerase β chain family. Existing as the second largest component of the multi-protein RNA polymerase III (Pol III) complex, POLR3B functions as a DNA-dependent RNA polymerase that specifically catalyzes the transcription of DNA into RNA using ribonucleoside triphosphates as substrates. The gene encoding POLR3B maps to human chromosome 12, which encodes over 1,100 genes and comprises approximately 4.5% of the human genome. Chromosome 12 is associated with a variety of diseases and afflictions, including hypochondrogenesis, achondrogenesis, Kniest dysplasia, Noonan syndrome and Trisomy 12p, which causes facial developmental defects and seizure disorders.