Fig. 3
Model of SNX3 associated bound to micelles. a The experimentally driven molecular docking was based on the interaction of SNX3 with individual components, measuring CSPs for micelles (top) and c4-PI3P (middle). Asterisks mark residues with substantially broadened NMR lines. The membrane inserting residues were identified from PREs (bottom) obtained by adding 5 doxyl PC to 32 mM DHPC:CHAPS micelles in the absence (black) or presence of c8-PI3P (gray). b Strips extracted from the 1H-1H planes of 13C-edited HSQC-NOESY spectra and corresponding to Ile109’s δ1 13C resonances are compared for SNX3 bound to micelles and c4-PI3P (red) or ligand-free (black). The overlaid 13C-HSQC spectra show crosspeaks of free and ligand-bound SNX3 (top). The c4-PI3P resonances (yellow) are indicated in NMR correlation spectrum alongside the DHPC: CHAPS peaks (green). These asymmetric crosspeaks correspond to intermolecular NOEs between SNX3 and PI3P. c The interactions between PI3P and SNX3 residues are depicted. The recognized non-exchangeable inositol protons are color-coded to match the interacting residue. Conserved hydrogen bonds observed in PX: PI3P structures are represented by dotted lines. d Docked structure of the lowest energy complex between SNX3, PI3P and micelles. Residues active during the docking are indicated on SNX3. Significant CSPs for Ins(1,3)P2 (orange) and/or micelles (yellow) are shown. Those involved in intermolecular interactions with PI3P (red) or micelles insertion (blue) are also displayed. The phosphate groups of PI3P are indicated by P1 and P3
