Human TFIIIC relieves chromatin-mediated repression of RNA polymerase III transcription and contains an intrinsic histone acetyltransferase activity.
Human TFIIIC is a multisubunit factor that is essential for transcription by RNA polymerase III on tRNA and virus-associated RNA genes and initiates preinitiation complex assembly by direct recognition of promoter elements. We show that highly purified TFIIIC, at concentrations above those sufficient for transcription of naked DNA templates, effectively relieves nucleosome-mediated repression on an in vitro-reconstituted chromatin template. Highly purified TFIIIC alone can bind to the A and B boxes of a tRNA gene within a chromatin template and, further, displays a histone acetyltransferase activity that is intrinsic to at least one (and probably three) of its subunits. The possibility of a direct link between TFIIIC-dependent chromatin transcription and acetyltransferase activities is suggested by the partial loss of these activities, but not DNA transcription activity, following pretreatment of TFIIIC with p-hydroxymercuribenzoic acid.
Kundu
T K
TK
Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, New York 10021, USA.
Wang
Z
Z
Roeder
R G
RG
D000123:Acetyltransferases / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D002843:Chromatin / Q000235:genetics* / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D006367:HeLa Cells; D051548:Histone Acetyltransferases; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011487:Protein Conformation; D012320:RNA Polymerase III / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D019474:Transcription Factors, TFIII; D014158:Transcription, Genetic; D000098832:Transcription Factor TFIIIC
D002843:Chromatin; D017931:DNA Primers; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D019474:Transcription Factors, TFIII; D000098832:Transcription Factor TFIIIC; D000123:Acetyltransferases; D051548:Histone Acetyltransferases; D012320:RNA Polymerase III