Skip to Main content Skip to Navigation
Journal articles

Rim1 modulates direct G-protein regulation of Ca(v)2.2 channels.

Abstract : Regulation of presynaptic voltage-gated calcium channels is critical for depolarization-evoked neurotransmitter release. Various studies attempted to determine the functional implication of Rim1, a component of the vesicle release machinery. Besides to couple voltage-gated Ca(2+) channels to the presynaptic vesicle release machinery, it was evidenced that Rim1 also prevents voltage-dependent inactivation of the channels through a direct interaction with the ancillary β-subunits, thus facilitating neurotransmitter release. However, facilitation of synaptic activity may also be caused by a reduction of the inhibitory pathway carried by G-protein-coupled receptors. Here, we explored the functional implication of Rim1 in G-protein regulation of Ca(v)2.2 channels. Activation of μ-opioid receptors expressed in HEK-293 cells along with Ca(v)2.2 channels produced a drastic current inhibition both in control and Rim1-expressing cells. In contrast, Rim1 considerably promoted the extent of current deinhibition following channel activation, favoring sustained Ca(2+) influx under prolonged activity. Our data suggest that Rim1-induced facilitation of neurotransmitter release may come as a consequence of a decrease in the inhibitory pathway carried by G-proteins that contributes, together with the slowing of channel inactivation, to maintain Ca(2+) influx under prolonged activity. The present study also furthers functional insights in the importance of proteins from the presynaptic vesicle complex in the regulation of voltage-gated Ca(2+) channels by G-proteins.
Document type :
Journal articles
Complete list of metadatas

Cited literature [35 references]  Display  Hide  Download

https://www.hal.inserm.fr/inserm-00587552
Contributor : Marco Canepari <>
Submitted on : Wednesday, April 20, 2011 - 5:15:44 PM
Last modification on : Tuesday, April 14, 2020 - 1:32:03 PM
Long-term archiving on: : Thursday, July 21, 2011 - 2:51:20 AM

Files

Weiss_2011_Rim1_modulates_MA.p...
Files produced by the author(s)

Identifiers

Collections

U836 | UGA

Citation

Norbert Weiss, Alejandro Sandoval, Shigeki Kyonaka, Ricardo Felix, Yasuo Mori, et al.. Rim1 modulates direct G-protein regulation of Ca(v)2.2 channels.. Pflügers Archiv European Journal of Physiology, Springer Verlag, 2011, 461 (4), pp.447-59. ⟨10.1007/s00424-011-0926-5⟩. ⟨inserm-00587552⟩

Share

Metrics

Record views

265

Files downloads

732