Structural analysis of rhodopsin states in megabody complexes

Bovine rhodopsin (bRho), the most intensively studied G protein–coupled receptor (GPCR), is activated by light-induced isomerization of its chromophore 11-cis-retinal to all-trans-retinal. This study employed cryogenic electron microscopy (cryo-EM) to investigate rhodopsin structure using a megabody (Mb7) as a negative allosteric modulator.

The data shows the chromatographic purification of Mb7 in complex with bRho, and Mb7 in complex with apo-rhodopsin (Opsin). In addition, we show UV-visible absorption spectra, together with time course of A470 nm and fluorescence emission, that demonstrate that Mb7 acts as a negative allosteric modulator by shifting the equilibrium of photoactivated rhodopsin (bRho*) from the active Meta-II conformation to the inactive Meta-I state.