Figure 1. Monomeric IDP structural features and dynamics.
Figure top depicts the principle of diffusion smFRET and FCS detection. Data Panel A is adapted from Crick et al. Proc. Natl. Acad. Sci. (2006) 103:16764, and shows the scaling of diffusion times vs. chain length as measured by FCS. Panels B and C are from Mukhopadhyay et al. Proc. Natl. Acad. Sci. (2007) 104:2649, which show evidence for rapid IDP fluctuations via a relatively narrow smFRET peak on FRET efficiency vs. population (number of events) histogram (B) and rapid-timescale FCS decays (C).