Optical control of endogenous proteins with a photoswitchable conditional subunit reveals a role for TREK1 in GABA(B) signaling.
Selective ligands are lacking for many neuronal signaling proteins. Photoswitched tethered ligands (PTLs) have enabled fast and reversible control of specific proteins containing a PTL anchoring site and have been used to remote control overexpressed proteins. We report here a scheme for optical remote control of native proteins using a "photoswitchable conditional subunit" (PCS), which contains the PTL anchoring site as well as a mutation that prevents it from reaching the plasma membrane. In cells lacking native subunits for the protein, the PCS remains nonfunctional internally. However, in cells expressing native subunits, the native subunit and PCS coassemble, traffic to the plasma membrane, and place the native protein under optical control provided by the coassembled PCS. We apply this approach to the TREK1 potassium channel, which lacks selective, reversible blockers. We find that TREK1, typically considered to be a leak channel, contributes to the hippocampal GABA(B) response.
Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, 271 Life Sciences Addition, University of California, Berkeley, Berkeley, CA 94720, USA.
Guillaume
G
Sandoz
Joshua
J
Levitz
Richard H
RH
Kramer
Ehud Y
EY
Isacoff
D000818:Animals; D002478:Cells, Cultured; D006624:Hippocampus / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D024683:Potassium Channels, Tandem Pore Domain / Q000378:metabolism*; D021122:Protein Subunits / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018080:Receptors, GABA-B / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*
D024683:Potassium Channels, Tandem Pore Domain; D021122:Protein Subunits; D018080:Receptors, GABA-B; C103742:potassium channel protein TREK-1