The adenovirus major late transcription factor USF is a member of the helix-loop-helix group of regulatory proteins and binds to DNA as a dimer.
We isolated full-length cDNAs encoding the 43-kD form of human upstream stimulatory factor (USF), a cellular factor required for efficient transcription of the adenovirus major late (AdML) promoter in vitro. Sequence analysis showed USF to be a member of the c-myc-related family of DNA-binding proteins. Using proteins translated in vitro, we identified a DNA-binding domain near the carboxyl terminus, which includes both a helix-loop-helix motif and a leucine repeat. We show that USF interacts with its target DNA as a dimer. The leucine repeat is required for efficient DNA binding of the intact protein and for interactions between full-length and truncated USF proteins. Interestingly, it is not required for DNA binding of the isolated helix-loop-helix domain. The structure of different cDNA clones indicates that USF RNA is differentially spliced, and alternative exon usage may regulate the levels of functional USF protein.
Gregor
P D
PD
Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021-6999.
Sawadogo
M
M
Roeder
R G
RG
D000260:Adenoviruses, Human / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D001704:Biopolymers; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004268:DNA-Binding Proteins; D006801:Humans; D007930:Leucine / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis / Q000235:genetics; D012326:RNA Splicing / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics; D051720:Upstream Stimulatory Factors
D001704:Biopolymers; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C497181:USF1 protein, human; D051720:Upstream Stimulatory Factors; D004247:DNA; D007930:Leucine