Component of the viral DNA-dependent RNA polymerase which is composed of four equimolar subunits of LEF-4, LEF-8, LEF-9, and p47. Plays an essential role in late and very late gene expression. a ribonucleoside 5'-triphosphate + RNA(n) = diphosphate + RNA(n+1) Interacts with LEF-4, LEF-9, and p47. Belongs to the RNA polymerase beta chain family.