Fig. 1: Sox2 C-IDR is disordered and dynamic.
From: DNA binding redistributes activation domain ensemble and accessibility in pioneer factor Sox2
a Schematics of Sox2 illustrating the main constructs used in this study. The plot shows disorder predictions as a function of residue number, based on two different predictors (Disopred377 (dashed line), AlphaFold22 normalised pLDDT (solid line)). The DBD is indicated, as are the ADs and serine-rich region (see text for details), and the locations of charged residues. b Far-UV circular dichroism spectra of different Sox2 variants at 5 µM concentration; Full-length Sox2 (blue), C-IDR (grey), N-DBD (green). Spectra are averages of n = 3 independent measurements. c, d Single-molecule transfer efficiency histograms of Sox2 fluorescently labelled flanking the DBD (residues 37 and 120, number of molecules=5323) or probing the entire C-IDR (residues 120–315, number of molecules = 14,544). The small peak at E ~ 0 originates from donor-only labelled molecules that remain after filtering (see Methods and Supplementary Fig. 1). e Fluorescence lifetime analysis of the Sox2 C-IDR. The 2D-correlation plot shows fluorescence lifetimes of the Cy3b donor (τDA) relative to the intrinsic donor fluorescence (τD). The dynamic line is based on a SAW-ν polymer model. See text for details. f 1H15N-HSQC spectrum of full-length Sox2. g Cα SCS plot of full-length Sox2 (blue). SCSs for the DBD (green) were determined for the isolated N-DBD domain. The known helix locations (UniProt P48431) are indicated, and grey shaded areas indicate the DBD and ADs. Source data are provided as a Source Data file.
