Fig. 6: Chaperones suppress PHOX2B de-mixing arresting nascent conformations.
From: Alternative low-populated conformations prompt phase transitions in polyalanine repeat expansions
A Turbidity at 25 °C for 0.225 mM XS23 or XS26 in presence of 0.1 mM HSP70 (blue and magenta, respectively). Plots for the unaccompanied PHOX2B constructs are included. B Fluorescence microscopy images for XS26 (0.1 mM, labeled with ATTO-565) in the absence and presence of HSP70. Scale bars = 10 μm. Data were biologically reproduced three times. C 15N-HSQC-based signal intensity plots for XS26 major conformation (0.07 mM) in complex with HSP70 (magenta) and HSP90 (green), all in 1:2 molar ratios. Green shadow limits polyAla α-helix. D XS26 (0.225 mM) CACO signal intensity decay upon incubation (2 days at 25 °C) in presence of HSP70 (1:2 equivalents, in magenta) and HSP70:DNAJB1 (1:2:1 equivalents, in yellow). Green shadow limits polyAla α-helix, while purple shadow limits nascent disordered alanine moieties (plotted on the right). Broken lines mark the average intensity for the different segments. E PARMs promote disorder in PHOX2B polyAla segment triggering fast phase transitions. Chaperones arrest nascent disordered conformations blocking phase separation. Source data are provided as a Source Data file.
