Stochastic dynamics of adhesion clusters under shared constant force
and with rebinding

T. Erdmann and U. S. Schwarz

J. Chem. Phys. 121: 8997-9017 (2004)

Single receptor-ligand bonds have finite lifetimes, so that biological
systems can dynamically react to changes in their environment. In cell
adhesion, adhesion bonds usually act cooperatively in adhesion
clusters. Outside the cellular context, adhesion clusters can be
probed quantitatively by attaching receptors and ligands to opposing
surfaces. Here we present a detailed theoretical analysis of the
stochastic dynamics of a cluster of parallel bonds under shared
constant loading and with rebinding. Analytical solutions for the
appropriate one-step master equation are presented for special cases,
while the general case is treated with exact stochastic
simulations. If the completely dissociated state is modeled as an
absorbing boundary, mean cluster lifetime is finite and can be
calculated exactly.  We also present a detailed analysis of
fluctuation effects and discuss various approximations to the full
stochastic description.