DNA-directed RNA polymerase II subunit RPB11-b2(POLR2J3) is a member of the eukaryotic RPB11 RNA polymerase subunit family. POLR2J(DNA-directed RNA polymerase II subunit J) exists in 3 variants POLR2J1(RPB11-a), POLR2J2(RPB11-b1), and POLR2J3(RPB11-b2). POLR2J3 is a DNA-dependent RNA polymerase which catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.