Regulation of DNA replication in vitro by the transcriptional activation domain of GAL4-VP16.
Studies of DNA viruses have provided evidence that eukaryotic transcriptional activator proteins can enhance the efficiency of DNA replication as well as transcription. The mechanism of this effect was studied in vitro using the chimeric transcription factor GAL4-VP16 and a DNA template containing GAL4 binding sites adjacent to the simian virus 40 origin of DNA replication. The binding of GAL4-VP16 prevented the repression of DNA replication which otherwise occurred when the template was assembled into chromatin. Relief of repression by GAL4-VP16 required both its DNA-binding and transcriptional activation domains but did not require RNA synthesis. The results are consistent with a general model in which transcriptional activators stimulate eukaryotic DNA replication by modifying the outcome of the competition between initiation factors and histones for occupancy of the origin.
Cheng
L Z
LZ
Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Workman
J L
JL
Kingston
R E
RE
Kelly
T J
TJ
D004261:DNA Replication; D004279:DNA, Viral / Q000235:genetics; D004268:DNA-Binding Proteins / Q000502:physiology; D005656:Fungal Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D011993:Recombinant Fusion Proteins; D012045:Regulatory Sequences, Nucleic Acid; D029701:Saccharomyces cerevisiae Proteins; D013539:Simian virus 40 / Q000235:genetics*; D013329:Structure-Activity Relationship; D015534:Trans-Activators; D014157:Transcription Factors / Q000502:physiology*; D014764:Viral Proteins / Q000378:metabolism
D004279:DNA, Viral; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D014764:Viral Proteins