How do G proteins directly control neuronal Ca2+ channel function?

Michel De Waard; Julien Hering; Norbert Weiss; Anne Feltz

doi:10.1016/j.tips.2005.06.008

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How do G proteins directly control neuronal Ca2+ channel function?

Michel De Waard·Julien Hering·Norbert Weiss·Anne Feltz

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Abstract

Ca2+ entry into neuronal cells is modulated by the activation of numerous G-protein-coupled receptors (GPCRs). Much effort has been invested in studying direct G-protein-mediated inhibition of voltage-dependent CaV2 Ca2+ channels. This inhibition occurs through a series of convergent modifications in the biophysical properties of the channels. An integrated view of the structural organization of the Gbetagamma-dimer binding-site pocket within the channel is emerging. In this review, we discuss how variable geometry of the Gbetagamma binding pocket can yield distinct sets of channel inhibition. In addition, we propose specific mechanisms for the regulation of the channel by G proteins that take into account the regulatory input of each Gbetagamma binding element.

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Amino Acid Sequence Animals Binding Sites Calcium Channels GTP-Binding Proteins Humans Models, Molecular Molecular Sequence Data Neurons Protein Binding Sequence Homology, Amino Acid Journal Article Research Support, Non-U.S. Gov't Review

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Michel De Waard, Julien Hering, Norbert Weiss, Anne Feltz. 2005. How do G proteins directly control neuronal Ca2+ channel function?. https://doi.org/10.1016/j.tips.2005.06.008

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