Molecular architecture of photoreceptor phosphodiesterase elucidated by chemical cross-linking and integrative modeling.

ABSTRACT: Photoreceptor phosphodiesterase (PDE6) is the central effector enzyme in visual excitation pathway in rod and cone photoreceptors. Its tight regulation is essential for the speed, sensitivity, recovery and adaptation of visual detection. Although major steps in the PDE6 activation/deactivation pathway have been identified, mechanistic understanding of PDE6 regulation is limited by the lack of knowledge about the molecular organization of the PDE6 holoenzyme (αβγγ). Here, we characterize the PDE6 holoenzyme by integrative structural determination of the PDE6 catalytic dimer (αβ), based primarily on chemical cross-linking and mass spectrometric analysis. Our models built from high-density cross-linking data elucidate a parallel organization of the two catalytic subunits, with juxtaposed α-he

SUBMITTER: Zeng-Elmore X 

PROVIDER: S-EPMC4253074 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature