Figure 3. Effect of phosphorylation and binding partner on the order-disorder/assembly-disassembly transitions of Npm-N.
(a) smFRET histograms for the phospho-mimicking variant S48E at low-salt, and at two different time points after the addition of 150 mM NaCl. (b) smFRET histograms of Npm-N showing three state (UM, IM and FM) folding pathway induced by Arf6. (c) Various Arf fragments arrest Npm-N in the pentameric state at low salt, which otherwise leads to complete disassembly. (d) Arf fragments counteract the unfolding-disassembly of the phospho-variants at low salt. The horizontal line represents FRET signal observed in absence of any Arf. The time values in the parenthesis in (a) and (b) indicate uncertainties due to finite data acquisition time.