Force activation of I domain containing and lacking integrins on live cells
MetadataShow full item record
Cellular adhesion plays a crucial role in the biological function of cells, allowing them to communicate and signal, as well as physically anchor, by enabling them to adhere to either other cells or the extra cellular matrix (ECM). This process is regulated by several factors including intrinsic bond kinetics, internal cellular signaling, environment, force exerted on the bond, and force history of the bond. Concerning the force and force history dependence, the observation of catch bonds in integrin binding has asked as more questions than it has answered. To explore the force and force history dependence this process, each bond was loaded to a peak force before relaxing to a much lower force that was held for the duration of the measurement. Two different integrins were studied, both of which have in previous works exhibited a catch bond. Furthermore, the effects of different metal ion conditions and an allosteric antagonist were also studied to elucidate the conformational effects on force priming of integrin. What was observed was that I domain, or αA domain, possessing integrin, whether tested against its more active or less active binding state, changed very little in terms of off rate once the priming force was applied. However in the I domain, or αA domain, lacking integrin, the observed off rate changed as well. It seems that force priming is capable of causing integrin to bind in a stronger manner regardless of the other conditions used to either activate or inhibit binding. However the way in which the binding is strengthened depends on the receptors structure.