Fig. 6. Membrane binding of Crac-GFP in cells lacking ACA. Dissociation curves of Crac-GFP in wild-type (
) and aca-null cells (
). Cells that lack ACA have only a fast-dissociation site but lack the slow-dissociation site for Crac-GFP, suggesting that the slow-dissociation site is either ACA itself or an ACA-dependent molecule on membranes.