ABSTRACT: IscU is a scaffold protein that functions in iron-sulfur cluster assembly and transfer. Its critical importance has been recently underscored by the finding that a single intronic mutation in the human iscu gene is associated with a myopathy resulting from deficient succinate dehydrogenase and aconitase [Mochel, F., Knight, M. A., Tong, W. H., Hernandez, D., Ayyad, K., Taivassalo, T., Andersen, P. M., Singleton, A., Rouault, T. A., Fischbeck, K. H., and Haller, R. G. (2008) Am. J. Hum. Genet. 82, 652-660]. IscU functions through interactions with a chaperone protein HscA and a cochaperone protein HscB. To probe the molecular basis for these interactions, we have used NMR spectroscopy to investigate the solution structure of IscU from Escherichia coli and its interaction with HscB from the
