Related Experiment Videos
Solution structure of a DNA-binding domain from HMG1
C M Read1, P D Cary, C Crane-Robinson
1Biophysics Laboratories, School of Biological Sciences, University of Portsmouth.
Nucleic Acids Research
|July 25, 1993
Summary
Researchers determined the 3D structure of hamster HMG1 box 2, revealing a novel V-shaped fold. This structure explains DNA binding mutations and suggests interactions with bent DNA structures.
Area of Science:
- Structural biology
- Biochemistry
- Molecular genetics
Background:
- High mobility group (HMG) proteins are crucial for DNA binding and chromatin remodeling.
- The HMG box domain is a conserved motif found in various HMG proteins.
- Understanding the HMG box structure is key to deciphering its role in DNA interactions.
Purpose of the Study:
- To determine the tertiary structure of the HMG box 2 domain from hamster HMG1.
- To elucidate the structural basis for DNA binding and interactions with specific DNA conformations.
Main Methods:
- Bacterial expression of hamster HMG1 box 2.
- Three-dimensional (3D) Nuclear Magnetic Resonance (NMR) spectroscopy for structure determination.
Main Results:
- The tertiary structure of HMG1 box 2 was determined, revealing an all alpha-helical, V-shaped fold.
- This fold is distinct from known DNA-binding motifs.
- Conserved residues are primarily involved in maintaining the tertiary structure, suggesting a conserved fold across HMG boxes.
- The structure provides insights into mutations affecting DNA binding and suggests interactions with bent and 4-way junction DNA.
Conclusions:
- The determined V-shaped fold of HMG1 box 2 is a novel architecture for DNA-binding domains.
- Homologous HMG boxes likely share a similar fold, crucial for structural integrity.
- The structural information facilitates understanding of HMG box mutations and their impact on DNA binding, particularly with non-canonical DNA structures.