Figure 2.

Competition in PT binding to VC1 by CaCl₂. The pulldown assays were carried out in 20 mm HEPES, 100 mm NaCl, 0.5% Triton X-100, pH 7.1, before and after addition to plasma of increasing concentrations of CaCl₂. IN, input; UB, unbound fraction; B, bound material obtained after boiling the beads for 5 min in SDS sample buffer. A, proteins were analyzed by SDS-PAGE and stained by Coomassie Blue. B, Western blot (WB) analysis of the fractions of pulldown assays using anti-PT mAb. C, Western blot analysis of the fractions from pulldown assays using anti-Gla mAb. Arrowhead, PT. VC1, VC1 domain.