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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
LEGO-NMR spectroscopy: a method to visualize individual subunits in large heteromeric complexes
Markus Mund1, Jan H Overbeck, Janina Ullmann
1Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen (Germany); Present address: European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg (Germany).
Angewandte Chemie (International Ed. in English)
|August 16, 2013
Summary
Researchers developed a LEGO-NMR technique to study large protein complexes. This method simplifies complex Nuclear Magnetic Resonance (NMR) spectra, revealing details about RNA binding sites in LSm1-7 and LSm2-8 rings.
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Macromolecular complexes are crucial in biological processes.
- Studying large, asymmetric complexes using Nuclear Magnetic Resonance (NMR) is challenging due to spectral complexity.
- Existing NMR methods struggle to provide high-resolution data for such systems.
Purpose of the Study:
- To develop a novel NMR-based technique for analyzing large, asymmetric macromolecular complexes.
- To simplify NMR spectral complexity by selectively activating subunits.
- To investigate the structure and function of heteroheptameric LSm1-7 and LSm2-8 rings.
Main Methods:
- Preparation of asymmetric macromolecular complexes with NMR activity in a subset of subunits.
- Application of the 'LEGO-NMR' technique for selective NMR signal generation.
- Analysis of NMR spectra to identify structural features and functional sites.
Main Results:
- Successfully obtained NMR spectra for individual subunits within the complete LSm1-7 and LSm2-8 complexes.
- Demonstrated that the LEGO-NMR approach significantly reduces spectral complexity.
- Identified a conserved RNA binding site across the studied LSm rings.
Conclusions:
- The LEGO-NMR technique is effective for studying large, asymmetric macromolecular complexes.
- This method provides detailed insights into the structure of heteroheptameric LSm rings.
- The findings pave the way for broader NMR applications in structural biology.
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