Human H1 histone gene promoter CCAAT box binding protein HiNF-B is a mosaic factor.
Vertebrate histone gene promoters in many cases contain an upstream element, 5'dCCAAT, that has been implicated in modulating the efficiency of transcription of a broad spectrum of genes. We have previously isolated a nuclear factor (HiNF-B) that binds specifically to the CCAAT element of a cell cycle regulated human H1 histone gene. This factor shows similarities with other CCAAT box binding proteins in that it recognizes the same sequence but shows a distinct chromatographic behavior. In the present study, we have employed the gel retardation assay to demonstrate that HiNF-B is a cell cycle independent DNA binding protein that is conserved in both human and mouse cells. Using a series of reconstitution experiments with partially purified HiNF-B fractions, we show that this factor requires association of at least two components for site-specific binding. The composite structure of HiNF-B suggests that binding of at least some CCAAT elements in vertebrates may require cooperative interaction of CCAAT box binding proteins with other factors.
van Wijnen
A J
AJ
Department of Cell Biology, University of Massachusetts Medical School, Worcester 01655.
Massung
R F
RF
Stein
J L
JL
Stein
G S
GS
D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D002467:Cell Nucleus / Q000378:metabolism; D015342:DNA Probes; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005796:Genes; D005822:Genetic Vectors; D006657:Histones / Q000235:genetics*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009030:Mosaicism; D011401:Promoter Regions, Genetic
D022762:CCAAT-Enhancer-Binding Proteins; D015342:DNA Probes; D004268:DNA-Binding Proteins; C058598:HiNF-B protein, human; C483812:HiNF-B protein, mouse; D006657:Histones