Direct determination of changes of interdomain orientation on ligation: use of the orientational dependence of 15N NMR relaxation in Abl SH(32).
The relative orientation and motions of domains within many proteins are key to the control of multivalent recognition, or the assembly of protein-based cellular machines. Current methods of structure determination have limited applicability to macromolecular assemblies, characterized by weak interactions between the constituents. Crystal structures of such complexes might be biased by packing forces comparable to the interdomain interactions, while the precision and accuracy of the conventional NMR structural approaches are necessarily limited by the restricted number of NOE contacts and by interdomain flexibility rendering the available NOE information uninterpretable. NMR relaxation studies are capable of providing "long-range" structural information on macromolecules in their native milieu. Here we determine directly the change in domain orientation between unligated and dual ligated subdomains of the SH(32) segment of Abelson kinase in solution, using the orientational dependence of nuclear spin relaxation. These results demonstrate that the change in domain orientation between unligated and ligated forms can be measured directly in solution.
Fushman
D
D
The Rockefeller University, New York 10021, USA.
Xu
R
R
Cowburn
D
D
D000577:Amides / Q000737:chemistry; D016880:Anisotropy; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D016315:Proto-Oncogene Proteins c-abl / Q000737:chemistry* / Q000378:metabolism*; D013816:Thermodynamics; D013997:Time Factors; D018909:src Homology Domains
D000577:Amides; D008024:Ligands; D009587:Nitrogen Isotopes; D010446:Peptide Fragments; D016315:Proto-Oncogene Proteins c-abl