The acidic transcriptional activator GAL-VP16 acts on preformed template-committed complexes.
The action of the chimeric acidic transcriptional activator GAL-VP16 has been investigated by performing a series of kinetic experiments using the detergent Sarkosyl as well as monoclonal antibodies which specifically inhibit GAL-VP16 DNA binding and transcriptional activation. GAL-VP16 binds to recognition site rapidly, remains bound after transcriptional initiation and is required to maintain stimulated levels of reinitiation. GAL-VP16 action, which appears to result in an increase in the number of preinitiation complexes formed, occurs after the formation of template-committed complexes composed of promoter-bound TFIIA (STF) and a partially purified TFIID fraction conferring GAL-VP16 responsiveness on a reconstituted basal transcription system. This TFIID fraction cannot be replaced by TFIIB or cloned TFIID. Our results suggest that GAL-VP16 activates step(s) in preinitiation complex assembly occurring after TFIID has bound.
White
J
J
Laboratoire de Génétique Moléculaire des Eucaryotes, CNRS, Strasbourg, France.
Brou
C
C
Wu
J
J
Lutz
Y
Y
Moncollin
V
V
Chambon
P
P
D000911:Antibodies, Monoclonal; D001483:Base Sequence; D001665:Binding Sites; D002678:Chimera; D000939:Epitopes / Q000032:analysis; D005656:Fungal Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D015183:Restriction Mapping; D012521:Sarcosine / Q000031:analogs & derivatives / Q000494:pharmacology; D013698:Templates, Genetic; D015534:Trans-Activators / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
D000911:Antibodies, Monoclonal; D000939:Epitopes; D005656:Fungal Proteins; C070633:Gal-VP16; D009838:Oligodeoxyribonucleotides; D015534:Trans-Activators; C025231:sarkosyl; D012521:Sarcosine