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1mf6
From Proteopedia
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Transducin gamma subunit, C-terminal domain 60-71, rhodopsin-bound state: Ensemble of 15 models determined by TrNOE spectroscopy
Overview
Rhodopsin, a prototypical G protein-coupled receptor, catalyzes the activation of a heterotrimeric G protein, transducin, to initiate a visual signaling cascade in photoreceptor cells. The betagamma subunit complex, especially the C-terminal domain of the transducin gamma subunit, Gtgamma(60-71)farnesyl, plays a pivotal role in allosteric regulation of nucleotide exchange on the transducin alpha subunit by light-activated rhodopsin. We report that this domain is unstructured in the presence of an inactive receptor but forms an amphipathic helix upon rhodopsin activation. A K65E/E66K charge reversal mutant of the gamma subunit has diminished interactions with the receptor and fails to adopt the helical conformation. The identification of this conformational switch provides a mechanism for active GPCR utilization of the betagamma complex in signal transfer to G proteins.
About this Structure
1MF6 is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
Reference
Rhodopsin controls a conformational switch on the transducin gamma subunit., Kisselev OG, Downs MA, Structure. 2003 Apr;11(4):367-73. PMID:12679015
Page seeded by OCA on Sun Mar 30 22:15:21 2008
