A hypothesis for GPCR activation.

Jerzy Ciarkowski; Magdalena Witt; Rafał Slusarz

doi:10.1007/s00894-005-0270-9

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A hypothesis for GPCR activation.

Jerzy Ciarkowski·Magdalena Witt·Rafał Slusarz

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Abstract

Growing evidence that rhodopsin (RD) and related G protein-coupled receptors form functional dimers/oligomers, followed by direct proof (using atomic force microscopy) that in the retina disc membrane RD associates into a paracrystalline network of rows of dimers, need models of the RD-transducin (Gt) complex that would envision an optimal RD dimer/oligomer able to satisfy all well-documented interactions with Gt. Of the models proposed so far, only a few refer to RD dimers and only one of them proposes a complex of Gt with an RD oligomer (Filipek S, Krzyśko KA, Fotiadis D, Liang Y, Saperstein DA, Engel, A, Palczewski K Photochem Photobiol Sci 3: 628-638, 2004). This paper puts forward a hypothesis on another arrangement of RD monomers into the reported network of rows of dimers. Arguments for the compatibility of this set-up with interactions and activation of RD in the complex with Gt, in particular, with the well-documented movement of transmembrane helix 6 and cytosolic loop 3, which is vital for RD activation, are provided and discussed.

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Dimerization Models, Biological Models, Molecular Protein Conformation Receptors, G-Protein-Coupled Rhodopsin Signal Transduction Surface Properties Transducin Journal Article Research Support, Non-U.S. Gov't

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Jerzy Ciarkowski, Magdalena Witt, Rafał Slusarz. 2005-05-12. A hypothesis for GPCR activation.. https://doi.org/10.1007/s00894-005-0270-9

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