Figure 6. The purified ACD-cross-linked actin dimers are less good substrate for cross-linking than actin monomers.

5.0 μM actin monomers and 5.0 μM actin dimers, purified as described in the Experimental procedures, were cross-linked in the presence of 10 μM KabC, 0.01 μM LF_NACD (1 to 1000 mole ratio to actin), and 2.0 mM MgCl₂. The decay of the initial uncross-linked actin on 7.5% SDS-gel (A) was used as a measure of the cross-linking efficiency and plotted in (B). Closed circles represent the decay of uncross-linked monomeric actin, open circles represent decay of purified actin dimers. Experimental data were fitted to a single exponential expression (solid lines).