2D-heteronuclear correlation spectra provide the foundation for all biomolecular NMR studies, but traditional 1H-detected methods do not work as well for IDPs as newer 13C-detected methods. (A) The 1H,15N-HSQC of Pdx1-C (B) The 15N,13C-CON of Pdx1-C. Of special value is the presence of peaks corresponding to proline residues, seen downfield shifted in the nitrogen dimension of the 15N,13C-CON. Note that the amino acid sequence of Pdx1-C is provided at the top of the figure, with the N-terminal GPG cloning artifact shown in the thinner font. A larger version of panel (B) is provided in Fig. S1, including complete annotation of chemical shift assignments.