TY - JOUR
T1 - Substitution of 5-HT1A receptor signaling by a light-activated G protein-coupled receptor
AU - Oh, Eugene
AU - Maejima, Takashi
AU - Liu, Chen
AU - Deneris, Evan
AU - Herlitze, Stefan
PY - 2010/10/1
Y1 - 2010/10/1
N2 - Understanding serotonergic (5-HT) signaling is critical for understanding human physiology, behavior, and neuropsychiatric disease. 5-HT mediates its actions via ionotropic and metabotropic 5-HT receptors. The 5-HT1A receptor is a metabotropic G protein-coupled receptor linked to the G i/o signaling pathway and has been specifically implicated in the pathogenesis of depression and anxiety. To understand and precisely control 5-HT1A signaling, we created a light-activated G protein-coupled receptor that targets into 5-HT1A receptor domains and substitutes for endogenous 5-HT1A receptors. To induce 5-HT1A-like targeting, vertebrate rhodopsin was tagged with the C-terminal domain (CT) of 5-HT1A (Rh-CT5-HT1A). Rh-CT5-HT1A activates G protein-coupled inward rectifying K+ channels in response to light and causes membrane hyperpolarization in hippocampal neurons, similar to the agonist-induced responses of the 5-HT1A receptor. The intracellular distribution of Rh-CT5-HT1A resembles that of the 5-HT1A receptor; Rh-CT5-HT1A localizes to somatodendritic sites and is efficiently trafficked to distal dendritic processes. Additionally, neuronal expression of Rh-CT5-HT1A, but not Rh, decreases 5-HT1A agonist sensitivity, suggesting that Rh-CT5-HT1A and 5-HT 1A receptors compete to interact with the same trafficking machinery. Finally, Rh-CT5-HT1A is able to rescue 5-HT1A signaling of 5-HT1A KO mice in cultured neurons and in slices of the dorsal raphe showing that Rh-CT5-HT1A is able to functionally compensate for native5-HT1A. Thus, as an optogenetic tool, Rh-CT5-HT1A has the potential to directly correlate in vivo 5-HT1A signaling with 5-HT neuron activity and behavior in both normal animals and animal models of neuropsychiatric disease.
AB - Understanding serotonergic (5-HT) signaling is critical for understanding human physiology, behavior, and neuropsychiatric disease. 5-HT mediates its actions via ionotropic and metabotropic 5-HT receptors. The 5-HT1A receptor is a metabotropic G protein-coupled receptor linked to the G i/o signaling pathway and has been specifically implicated in the pathogenesis of depression and anxiety. To understand and precisely control 5-HT1A signaling, we created a light-activated G protein-coupled receptor that targets into 5-HT1A receptor domains and substitutes for endogenous 5-HT1A receptors. To induce 5-HT1A-like targeting, vertebrate rhodopsin was tagged with the C-terminal domain (CT) of 5-HT1A (Rh-CT5-HT1A). Rh-CT5-HT1A activates G protein-coupled inward rectifying K+ channels in response to light and causes membrane hyperpolarization in hippocampal neurons, similar to the agonist-induced responses of the 5-HT1A receptor. The intracellular distribution of Rh-CT5-HT1A resembles that of the 5-HT1A receptor; Rh-CT5-HT1A localizes to somatodendritic sites and is efficiently trafficked to distal dendritic processes. Additionally, neuronal expression of Rh-CT5-HT1A, but not Rh, decreases 5-HT1A agonist sensitivity, suggesting that Rh-CT5-HT1A and 5-HT 1A receptors compete to interact with the same trafficking machinery. Finally, Rh-CT5-HT1A is able to rescue 5-HT1A signaling of 5-HT1A KO mice in cultured neurons and in slices of the dorsal raphe showing that Rh-CT5-HT1A is able to functionally compensate for native5-HT1A. Thus, as an optogenetic tool, Rh-CT5-HT1A has the potential to directly correlate in vivo 5-HT1A signaling with 5-HT neuron activity and behavior in both normal animals and animal models of neuropsychiatric disease.
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U2 - 10.1074/jbc.M110.147298
DO - 10.1074/jbc.M110.147298
M3 - Article
C2 - 20643652
AN - SCOPUS:77957281947
SN - 0021-9258
VL - 285
SP - 30825
EP - 30836
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 40
ER -