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Tracking transmitter-gated P2X cation channel activation in vitro and in vivo.

ABSTRACT: We present a noninvasive approach to track activation of ATP-gated P2X receptors and potentially other transmitter-gated cation channels that show calcium fluxes. We genetically engineered rat P2X receptors to carry calcium sensors near the channel pore and tested this as a reporter for P2X(2) receptor opening. The method has several advantages over previous attempts to image P2X channel activation by fluorescence resonance energy transfer (FRET): notably, it reports channel opening rather than a conformation change in the receptor protein. Our FRET-based imaging approach can be used as a general method to track, in real time, the location, regional expression variation, mobility and activation of transmitter-gated P2X channels in living neurons in vitro and in vivo. This approach should help to determine when, where and how different receptors are activated during physiological processes.

SUBMITTER: Richler E

PROVIDER: S-EPMC3523716 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Tracking transmitter-gated P2X cation channel activation in vitro and in vivo.

Richler Esther E Chaumont Severine S Shigetomi Eiji E Sagasti Alvaro A Khakh Baljit S BS

Nature methods 20071216 1

We present a noninvasive approach to track activation of ATP-gated P2X receptors and potentially other transmitter-gated cation channels that show calcium fluxes. We genetically engineered rat P2X receptors to carry calcium sensors near the channel pore and tested this as a reporter for P2X(2) receptor opening. The method has several advantages over previous attempts to image P2X channel activation by fluorescence resonance energy transfer (FRET): notably, it reports channel opening rather than ...[more]

PMID: 18084300

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