A protein involved in minichromosome maintenance in yeast binds a transcriptional enhancer conserved in eukaryotes.
The Saccharomyces cerevisiae MCM1 gene product is a protein with multiple functions. It is a transcription factor necessary for expression of mating-type-specific genes and is also required for the maintenance of minichromosomes. MCM1 shows DNA-binding specificities similar to those of two previously reported DNA-binding factors, pheromone/receptor transcription factor (PRTF) and general regulator of mating type (GRM); like PRTF, its activity can be modulated by the alpha 1 protein. MCM1 binds to the dyad symmetry element 5'-CCTAATTAGG and related sequences, which we refer to as MCM1 control elements (MCEs). MCEs are found within the regulatory regions of a- and alpha-specific genes. Direct and indirect DNA binding assays suggest that a conserved 5'-ATTAGG in one-half of the dyad symmetry element is important for MCM1 binding whereas variants in the other half are tolerated. We have used a novel DNase I 'nicking interference' assay to investigate the interaction of MCM1 with its substrate. These data suggest that MCM1 binds as a dimer, interacting symmetrically with the ATTAGG residues in each half of the binding site. MCM1 contains striking homology to the DNA-binding domain of the human serum response factor (SRF) which mediates the transient transcriptional activation of growth-stimulated genes by binding to the serum response element (SRE). We have shown that MCM1 binds to the human c-fos SRE in vitro and, like other MCEs, the c-fos SRE exhibits MCM1-mediated upstream activating sequence (UAS) activity in vivo.
Passmore
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Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853.
Elble
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Tye
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BK
D001483:Base Sequence; D001667:Binding, Competitive; D004271:DNA, Fungal / Q000378:metabolism*; D003851:Deoxyribonucleases / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
D004271:DNA, Fungal; D014157:Transcription Factors; D003851:Deoxyribonucleases