Large self-assembled clathrin lattices spontaneously disassemble without sufficient adaptor proteins
Fig 4
Clathrin lattices at physiologic-like geometries fail to assemble until adaptor concentration reaches 0.6μM.
(A) Kinetics of the largest clathrin lattice assembly is faster and reaches larger sizes with increasing adaptor concentration. All simulations have 0.65μM clathrin. (B) Lag times and steepness of initial growth determined from simulation (black and red dots, respectively) follow the theoretical expressions of Eq 2 and Eq 3 relatively well. We excluded the low concentrations where the kinetics is not well-described by the lag and exponential growth model of Eq 1. (C) Lag times are typically slower in these geometrically physiologic-like simulations and rate-limited by localization of clathrin to a membrane (term 1 in Eq 2) with far fewer adaptor binding sites than in vitro. (D) The size of the largest lattices increases with increasing adaptor concentration, transitioning from small to large lattices at ~0.8μM (black squares). At this point, the stoichiometry of clathrin:adaptor has reached 1:1 (orange circles).