Fig. 1
From: Osteogenesis imperfecta mutations in plastin 3 lead to impaired calcium regulation of actin bundling
PLS3 domain structure and effects of OI-linked PLS3 mutations on PLS3 properties (see also Supplementary Fig. S1). a A schematic diagram of plastin domain structure: EF EF-hands motifs, CBM calmodulin-binding motif, RD N-terminal regulatory domain, CH calponin-homology domains, ABD actin-binding domains, Core actin-binding core domain, Linker a flexible linker separating the CBM and ABD1. PLS3 amino acid residue numbers and the OI-causative PLS3 mutations are shown below and above the diagram, respectively. b A homology-based model of the PLS3 actin-binding core (color scheme as in a) generated by Phyre2.86 c Melting profiles of PLS3 osteoporosis mutants were recorded by DSF in three independent repetitions; averaged data were plotted as the negative first derivatives of fluorescence signals versus temperature with transition temperatures (Tm) summarized in Table 1. F-actin binding (d) and bundling (e) by WT and mutated PLS3 were analyzed by high- and low-speed co-sedimentation and characterized by Kd and [PLS3]50% respectively (given in Table 1). Error bars represent standard errors of the mean of three and two independent repetitions for binding and bundling experiments, respectively (see also Supplementary Fig. S4). f Sensitivity of the PLS3 mutants to Ca2+ was measured by the decrease in light scattering reflecting the dissociation of plastin-mediated F-actin bundles upon titration with CaCl2. Error bars represent standard errors of the mean of three independent experiments. The data were fit to a logistic curve to determine the pCa50% (provided in Table 1)
