• Open Access

Noncovalent Dimerization of Ubiquitin


  • Funding from the Ministry of Science and Technology of China (2009CB918600 to M.L.), the Chinese Academy of Sciences (KJCX2-EW-W05 to C.T.), and the National Natural Sciences Foundation of China (21073230 to C.T.) is acknowledged. We thank Christian Griesinger and G. Marius Clore for advice, and Yong Duan for careful reading of the manuscript.


original image

Another kind of dynamics: Ubiquitin noncovalently dimerizes with a dissociation constant of approximately 5 mM. The two subunits adopt an array of relative orientations, utilizing an interface also for binding to other proteins (see picture). Quaternary fluctuation among members of the dimer ensemble constitutes a different kind of dynamics that complements the tertiary dynamics of each ubiquitin subunit.