Fig. 1: The disordered N terminus of Spy is involved in client protein release.
From: Insights into the client protein release mechanism of the ATP-independent chaperone Spy
a Structure model of full-length Spy with the N- and C-termini colored in red and blue, respectively. The disordered termini were modeled using the CABS-dock software and docked to the crystal structure of Spy (PDB: 3O39), in which only residues 29–124 are visible15. For clarity, only one possible conformation of the termini is shown. b Schematic illustration of termini-truncated Spy variants used for the chaperone activity assay and kinetics assessment, where the numbers listed as suffixes describe the amino acids remaining in the variants, using this nomenclature wild type Spy is Spy1-138. The structured regions of Spy29-124 are represented by blue cylinders, and the N- and C-termini are shown as red and blue lines, respectively. c Chaperone activities of termini-truncated Spy variants in inhibiting the aggregation of DTT-reduced α-LA relative to the activity of Spy wild type. Abbreviation α-LA agg. Prev means α-LA aggregation Prevention. Comparison of the dissociation constants Kd (d), dissociation rate constants koff (e), and association rate constants kon (f) between termini-truncated Spy variants using the model client protein Im7AAW as the chaperone substrate. For c–f, individual data points (circles) and mean ± SD (n = 3 independent experiments) are shown. Statistical analysis was performed with Graphpad Prism 9.1.0 using one-way ANOVA with Tukey’s multiple comparisons test. Source data are provided as a Source Data file.
