Conformational dynamics of helix 8 in the GPCR rhodopsin controls arrestin activation in the desensitization process.

ABSTRACT: Arrestins are regulatory molecules for G-protein coupled receptor function. In visual rhodopsin, selective binding of arrestin to the cytoplasmic side of light-activated, phosphorylated rhodopsin (P-Rh*) terminates signaling via the G-protein transducin. While the "phosphate-sensor" of arrestin for the recognition of receptor-attached phosphates is identified, the molecular mechanism of arrestin binding and the involvement of receptor conformations in this process are still largely hypothetic. Here we used fluorescence pump-probe and time-resolved fluorescence depolarization measurements to investigate the kinetics of arrestin conformational changes and the corresponding nanosecond dynamical changes at the receptor surface. We show that at least two sequential conformational changes of arr

SUBMITTER: Kirchberg K 

PROVIDER: S-EPMC3219140 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature