Fig. 2

SDS–PAGE and electron microscopic analysis of co-sedimentation assay. Co-sedimentation assay for gelsolin using SDS–PAGE (a–c) and negative staining electron microscopy (d–f). a General tendency of band migration; actin-alone, actin + ABP34 actin + gelsolin, actin + ABP34 + gelsolin (Molar ratio of 1:1:1). b effect of gelsolin treatment on actin-bundling activity. Gelsolin was treated (molar ratio of 1:1:1) before (A-G-34, left) and after (A-34-G, right) the formation of actin bundles. c Effect of concentration variation (3 μM and 6 μM) of gelsolin on actin-bundling activity [i.e., two different mixtures of A-34-G at different molar ratio of 1:1:1 (left) and 1:1:2 (right)]. S indicates supernatant, while P represents pellet. M, Marker; A, Actin; G, 34, ABP34; G, Gelsolin. d–f Negatively stained fields (at 34,000 nominal magnifications) of F-actin + ABP34 + gelsolin mixed at a molar ratio of 1:1:1 (d); Actin–gelsolin–ABP34 at 1:1:1 ratio (e); and Actin–ABP34–gelsolin 1:1:2 ratio (f). Here the molecular states were dramatically changed when the molar ratio was modulated to 1:1:2 and depolymerization states of the mixture were visualized in (f, (c.f. c)). Scale bars represent 200 nm in each field