Fig. 4.

Effect of PKA phosphorylation on C0C2 motif structure and disorder, detected by TR-FRET (shown) and DEER (see SI Appendix, Fig. S2, dashed lines). (A) Distance distributions of probes flanking the cMyBP-C motif region (C248–S440C). (B) Illustration of PKA effects on motif tertiary order. Unphosphorylated C0C2 exhibits an ensemble of conformations, such as bent or extended C0C2 structures (blue and green boxes). Increased tertiary order or a molecular collapse in motif would result in sampling a much narrower distribution of dynamic conformations, depicted here as a single structure (red box).