Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Mol Cell Biol
1992 Nov 01;1211:4970-80. doi: 10.1128/mcb.12.11.4970-4980.1992.
Show Gene links
Show Anatomy links
Cooperative binding of the Xenopus RNA polymerase I transcription factor xUBF to repetitive ribosomal gene enhancers.
Putnam CD
,
Pikaard CS
.
???displayArticle.abstract???
Upstream binding factor (UBF) is a DNA-binding transcription factor implicated in ribosomal gene promoter and enhancer function in vertebrates. UBF is unusual in that it has multiple DNA-binding domains with homology to high-mobility-group (HMG) nonhistone chromosomal proteins 1 and 2. However, a recognizable DNA consensus sequence for UBF binding is lacking. In this study, we have used gel retardation and DNase I footprinting to examine Xenopus UBF (xUBF) binding to Xenopus laevis ribosomal gene enhancers. We show that UBF has a minimum requirement for about 60 bp of DNA, the size of the short enhancer variant in X. laevis. Stronger UBF binding occurs on the longer enhancer variant (81 bp) and on multiple enhancers linked head to tail. In vivo, Xenopus ribosomal gene enhancers exist in blocks of 10 alternating 60- and 81-bp repeats within the intergenic spacer. In vitro, UBF binds cooperatively to probes with 10 enhancers, with five intermediate complexes observed in titration experiments. This suggests that, on average, one UBF dimer binds every two enhancers. A single UBF dimer can produce a DNase I footprint ranging in size from approximately 30 to about 115 bp on enhancer probes of different lengths. This observation is consistent with the hypothesis that multiple DNA-binding domains or subdomains within UBF bind independently, forming more-stable interactions on longer probes.
Bachvarov,
The RNA polymerase I transcription factor xUBF contains 5 tandemly repeated HMG homology boxes.
1991, Pubmed,
Xenbase
Bachvarov,
The RNA polymerase I transcription factor xUBF contains 5 tandemly repeated HMG homology boxes.
1991,
Pubmed
,
Xenbase
Bell,
Assembly of alternative multiprotein complexes directs rRNA promoter selectivity.
1990,
Pubmed
Bell,
Molecular mechanisms governing species-specific transcription of ribosomal RNA.
1989,
Pubmed
,
Xenbase
Bell,
Functional cooperativity between transcription factors UBF1 and SL1 mediates human ribosomal RNA synthesis.
1988,
Pubmed
Boseley,
Sequence organization of the spacer DNA in a ribosomal gene unit of Xenopus laevis.
1979,
Pubmed
,
Xenbase
Busby,
Spacer sequences regulate transcription of ribosomal gene plasmids injected into Xenopus embryos.
1983,
Pubmed
,
Xenbase
Culotta,
Mouse and frog violate the paradigm of species-specific transcription of ribosomal RNA genes.
1987,
Pubmed
,
Xenbase
De Winter,
A complex array of sequences enhances ribosomal transcription in Xenopus laevis.
1987,
Pubmed
,
Xenbase
Dunaway,
A transcription factor, TFIS, interacts with both the promoter and enhancer of the Xenopus rRNA genes.
1989,
Pubmed
,
Xenbase
Grimaldi,
Multiple repeated units in Drosophila melanogaster ribosomal DNA spacer stimulate rRNA precursor transcription.
1988,
Pubmed
Grummt,
Ribosomal RNA transcription in vitro is species specific.
1982,
Pubmed
Hisatake,
Cloning and structural analysis of cDNA and the gene for mouse transcription factor UBF.
1991,
Pubmed
Jantzen,
Nucleolar transcription factor hUBF contains a DNA-binding motif with homology to HMG proteins.
1990,
Pubmed
Kuhn,
A 140-base-pair repetitive sequence element in the mouse rRNA gene spacer enhances transcription by RNA polymerase I in a cell-free system.
1990,
Pubmed
,
Xenbase
Labhart,
Enhancer-like properties of the 60/81 bp elements in the ribosomal gene spacer of Xenopus laevis.
1984,
Pubmed
,
Xenbase
Learned,
Human rRNA transcription is modulated by the coordinate binding of two factors to an upstream control element.
1986,
Pubmed
Learned,
Purification and characterization of a transcription factor that confers promoter specificity to human RNA polymerase I.
1985,
Pubmed
McStay,
xUBF contains a novel dimerization domain essential for RNA polymerase I transcription.
1991,
Pubmed
,
Xenbase
McStay,
xUBF and Rib 1 are both required for formation of a stable polymerase I promoter complex in X. laevis.
1991,
Pubmed
,
Xenbase
Miesfeld,
The absence of a human-specific ribosomal DNA transcription factor leads to nucleolar dominance in mouse greater than human hybrid cells.
1984,
Pubmed
Mishima,
Fractionation and reconstitution of factors required for accurate transcription of mammalian ribosomal RNA genes: identification of a species-dependent initiation factor.
1982,
Pubmed
Moss,
A transcriptional function for the repetitive ribosomal spacer in Xenopus laevis.
,
Pubmed
,
Xenbase
O'Mahony,
Identification of two forms of the RNA polymerase I transcription factor UBF.
1991,
Pubmed
Onishi,
On the mechanism of nucleolar dominance in mouse-human somatic cell hybrids.
1984,
Pubmed
Pape,
Half helical turn spacing changes convert a frog into a mouse rDNA promoter: a distant upstream domain determines the helix face of the initiation site.
1990,
Pubmed
,
Xenbase
Pape,
The Xenopus ribosomal DNA 60- and 81-base-pair repeats are position-dependent enhancers that function at the establishment of the preinitiation complex: analysis in vivo and in an enhancer-responsive in vitro system.
1989,
Pubmed
,
Xenbase
Parisi,
Similarity of human mitochondrial transcription factor 1 to high mobility group proteins.
1991,
Pubmed
Pikaard,
rUBF, an RNA polymerase I transcription factor from rats, produces DNase I footprints identical to those produced by xUBF, its homolog from frogs.
1990,
Pubmed
,
Xenbase
Pikaard,
Enhancers for RNA polymerase I in mouse ribosomal DNA.
1990,
Pubmed
,
Xenbase
Pikaard,
Sequence elements essential for function of the Xenopus laevis ribosomal DNA enhancers.
1988,
Pubmed
,
Xenbase
Pikaard,
The Xenopus ribosomal gene enhancers bind an essential polymerase I transcription factor, xUBF.
1989,
Pubmed
,
Xenbase
Reeder,
Regulatory elements of the generic ribosomal gene.
1989,
Pubmed
Reeder,
Mechanisms of nucleolar dominance in animals and plants.
1985,
Pubmed
Reeder,
Linker scanner mutagenesis of the Xenopus laevis ribosomal gene promoter.
1987,
Pubmed
,
Xenbase
Reeder,
Enhancers and ribosomal gene spacers.
1984,
Pubmed
,
Xenbase
Reeder,
The mechanism of nucleolar dominance in Xenopus hybrids.
1984,
Pubmed
,
Xenbase
Schnapp,
A growth-dependent transcription initiation factor (TIF-IA) interacting with RNA polymerase I regulates mouse ribosomal RNA synthesis.
1990,
Pubmed
Schnapp,
Transcription complex formation at the mouse rDNA promoter involves the stepwise association of four transcription factors and RNA polymerase I.
1991,
Pubmed
Sinclair,
A gene from the human sex-determining region encodes a protein with homology to a conserved DNA-binding motif.
1990,
Pubmed
Smith,
Characterization of factors that direct transcription of rat ribosomal DNA.
1990,
Pubmed
Sollner-Webb,
The nucleotide sequence of the initiation and termination sites for ribosomal RNA transcription in X. laevis.
1979,
Pubmed
,
Xenbase
