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2hap
From Proteopedia
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STRUCTURE OF A HAP1-18/DNA COMPLEX REVEALS THAT PROTEIN/DNA INTERACTIONS CAN HAVE DIRECT ALLOSTERIC EFFECTS ON TRANSCRIPTIONAL ACTIVATION
Overview
HAP1 is a yeast transcriptional activator that binds with equal affinity, to the dissimilar upstream activation sequences UAS1 and UAS(CYC7), but, activates transcription differentially when bound to each site. HAP1-18, harbors an amino acid change in the DNA binding domain. While binding UAS1, poorly, HAP1-18 binds UAS(CYC7) with wild-type properties and activates, transcription at elevated levels relative to HAP1. We have determined the, structure of HAP1-18-UAS(CYC7) and have compared it to HAP1-UAS(CYC7)., Unexpectedly, the single amino acid substitution in HAP1-18 nucleates a, significantly altered hydrogen bond interface between the protein and DNA, resulting in DNA conformational changes and an ordering of one N-terminal, arm of the protein dimer along the DNA minor groove. These observations, together with a large subset of transcriptionally defective mutations in, the HAP1 DNA-binding domain that map to the HAP1-DNA interface, suggest, that protein-DNA interactions may have direct allosteric effects on, transcriptional activation.
About this Structure
2HAP is a Single protein structure of sequence from Saccharomyces cerevisiae with ZN as ligand. Full crystallographic information is available from OCA.
Reference
Structure of HAP1-18-DNA implicates direct allosteric effect of protein-DNA interactions on transcriptional activation., King DA, Zhang L, Guarente L, Marmorstein R, Nat Struct Biol. 1999 Jan;6(1):22-7. PMID:9886287
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