Transcription of adenovirus-2 major late promoter inhibited by monoclonal antibody directed against RNA polymerases IIO and IIA

Abstract

Monoclonal antibody directed against RNA polymerases IIO and IIA completely inhibits specific transcription from the major late promoter of adenovirus-2. At comparable antibody concentrations, only a slight inhibition of polymerase III transcription of VA RNA I is observed. Inhibition of polymerase II transcription is specific for monoclonal IgM directed against RNA polymerase II. High concentrations of control IgM do not inhibit transcription. Specific transcription from the conalbumin and ovalbumin promoters is also inhibited by polymerase-specific monoclonal IgM but not control IgM. These results suggest that the in vitro transcription of the conalbumin, ovalbumin, and adenovirus-2 major late promoter is catalyzed by RNA polymerase(s) IIO and/or IIA but not RNA polymerase IIB. However, transcription from calf thymus DNA, known to contain nicks, is not inhibited by polymerase specific monoclonal antibody. Thus, the monoclonal antibody does not interfere with initiation or elongation of RNA polymerase from nonpromoter sites but does appear to selectively inhibit transcription from promoter sites.