The solution structure and activation of visual arrestin studied by small-angle X-ray scattering

35Citations
Citations of this article
29Readers
Mendeley users who have this article in their library.

Abstract

Visual arrestin is converted from a 'basal' state to an 'activated' state by interaction with the phosphorylated C-terminus of photoactivated rhodopsin (R*), but the conformational changes in arrestin that lead to activation are unknown. Small-angle X-ray scattering (SAXS) was used to investigate the solution structure of arrestin and characterize changes attendant upon activation. Wild-type arrestin forms dimers with a dissociation constant of 60 μM. Small conformational changes, consistent with local movements of loops or the mobile N- or C-termini of arrestin, were observed in the presence of a phosphopeptide corresponding to the C-terminus of rhodopsin, and with an R175Q mutant. Because both the phosphopeptide and the R175Q mutation promote binding to unphosphorylated R*, we conclude that arrestin is activated by subtle conformational changes. Most of the arrestin will be in a dimeric state in vivo. Using the arrestin structure as a guide [Hirsch, J.A., Schubert, C., Gurevich, V.V. & Sigler, P.B. (1999) Cell 97, 257-269], we have identified a model for the arrestin dimer that is consistent with our SAXS data. In this model, dimerization is mediated by the C-terminal domain of arrestin, leaving the N-terminal domains free for interaction with phosphorylated R*.

Cite

CITATION STYLE

APA

Shilton, B. H., McDowell, J. H., Smith, W. C., & Hargrave, P. A. (2002). The solution structure and activation of visual arrestin studied by small-angle X-ray scattering. European Journal of Biochemistry, 269(15), 3801–3809. https://doi.org/10.1046/j.1432-1033.2002.03071.x

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free