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1hwt
From Proteopedia
| 1hwt, resolution 2.50Å () | |||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
STRUCTURE OF A HAP1/DNA COMPLEX REVEALS DRAMATICALLY ASYMMETRIC DNA BINDING BY A HOMODIMERIC PROTEIN
HAP1 is a member of a family of fungal transcription factors that contain a Zn2Cys6 binuclear cluster domain and bind as homodimers to sequences containing two DNA half sites. We have determined the 2.5 A crystal structure of HAP1 bound to a cognate upstream activation sequence from the CYC7 gene. The structure reveals that HAP1 is bound in a dramatically asymmetric manner to the DNA target. This asymmetry aligns the Zn2Cys6 domains in a tandem head-to-tail fashion to contact two DNA half sites, positions an N-terminal arm of one of the protein subunits to interact with the inter-half site base pairs in the DNA minor groove, and suggests a mechanism by which DNA-binding facilitates asymmetric dimerization by HAP1. Comparisons with the DNA complexes of the related GAL4, PPR1 and PUT3 proteins illustrate how a conserved protein domain can be reoriented to recognize DNA half sites of different polarities and how homodimeric proteins adopt dramatically asymmetric structures to recognize cognate DNA targets.
Structure of a HAP1-DNA complex reveals dramatically asymmetric DNA binding by a homodimeric protein., King DA, Zhang L, Guarente L, Marmorstein R, Nat Struct Biol. 1999 Jan;6(1):64-71. PMID:9886294
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
1HWT is a 8 chains structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
- King DA, Zhang L, Guarente L, Marmorstein R. Structure of a HAP1-DNA complex reveals dramatically asymmetric DNA binding by a homodimeric protein. Nat Struct Biol. 1999 Jan;6(1):64-71. PMID:9886294 doi:10.1038/4940
Page seeded by OCA on Mon Feb 16 17:37:37 2009
