Figure 1.

Crystal structure and the mutagenesis studies of the SRCR domain of mSCARA1. A, schematic representation of SCARA1 domain arrangement. B, SEC profile and SDS-PAGE of the SRCR domain of mouse SCARA1. C, crystal structure of the SRCR domain of mouse SCARA1. Ca²⁺ is shown as a gray ball. D, Ca²⁺-binding site on the SRCR domain. The residues and water molecules (green) at the binding site are labeled. E, CL–SRCR fragment of mSCARA1 binds to the ActD-treated Jurkat cells in the presence of Ca²⁺, whereas the fragments with the Ca²⁺-binding site mutations do not bind to the dead cells. GFP is applied as a control. F, CL–SRCR fragment of mSCARA1 binds to the frozen–thawed NIH 3T3 cells in the presence of Ca²⁺, whereas the fragments with the Ca²⁺-binding site mutations do not bind to the dead cells. GFP is applied as a control.