1. Academic Validation
  2. A fluorescent sensor for spatiotemporally resolved imaging of endocannabinoid dynamics in vivo

A fluorescent sensor for spatiotemporally resolved imaging of endocannabinoid dynamics in vivo

  • Nat Biotechnol. 2022 May;40(5):787-798. doi: 10.1038/s41587-021-01074-4.
Ao Dong 1 2 3 Kaikai He 1 2 Barna Dudok 4 Jordan S Farrell 4 Wuqiang Guan 5 Daniel J Liput 6 7 Henry L Puhl 7 Ruyi Cai 1 2 Huan Wang 1 2 Jiali Duan 1 2 Eddy Albarran 8 Jun Ding 9 David M Lovinger 6 Bo Li 5 Ivan Soltesz 4 Yulong Li 10 11 12 13
Affiliations

Affiliations

  • 1 State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.
  • 2 PKU-IDG/McGovern Institute for Brain Research, Beijing, China.
  • 3 Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.
  • 4 Department of Neurosurgery, Stanford University, Palo Alto, CA, USA.
  • 5 Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
  • 6 Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA.
  • 7 Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA.
  • 8 Neuroscience PhD Program, Stanford University, Palo Alto, CA, USA.
  • 9 Department of Neurosurgery, Department of Neurology, Stanford University School of Medicine, Palo Alto, CA, USA.
  • 10 State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China. [email protected].
  • 11 PKU-IDG/McGovern Institute for Brain Research, Beijing, China. [email protected].
  • 12 Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China. [email protected].
  • 13 Chinese Institute for Brain Research, Beijing, China. [email protected].
Abstract

Endocannabinoids (eCBs) are retrograde neuromodulators with important functions in a wide range of physiological processes, but their in vivo dynamics remain largely uncharacterized. Here we developed a genetically encoded eCB sensor called GRABeCB2.0. GRABeCB2.0 consists of a circular-permutated EGFP and the human CB1 Cannabinoid Receptor, providing cell membrane trafficking, second-resolution kinetics with high specificity for eCBs, and shows a robust fluorescence response at physiological eCB concentrations. Using GRABeCB2.0, we monitored evoked and spontaneous changes in eCB dynamics in cultured neurons and acute brain slices. We observed spontaneous compartmentalized eCB transients in cultured neurons and eCB transients from single axonal boutons in acute brain slices, suggesting constrained, localized eCB signaling. When GRABeCB2.0 was expressed in the mouse brain, we observed foot shock-elicited and running-triggered eCB signaling in the basolateral amygdala and hippocampus, respectively. In a mouse model of epilepsy, we observed a spreading wave of eCB release that followed a Ca2+ wave through the hippocampus. GRABeCB2.0 is a robust probe for eCB release in vivo.

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