Cell-specific STORM super-resolution imaging reveals nanoscale organization of cannabinoid signaling

Abstract

A major challenge in neuroscience is to determine the nanoscale position and quantity of signaling molecules in a cell-type-, and subcellular compartment-specific manner. We therefore developed a novel approach combining cell-specific physiological and anatomical characterization with superresolution imaging, and studied the molecular and structural parameters shaping the physiological properties of synaptic endocannabinoid signaling in the mouse hippocampus. We found that axon terminals of perisomatically-projecting GABAergic interneurons possess increased CB1 receptor number, active-zone complexity, and receptor/effector ratio compared to dendritically-projecting interneurons, in agreement with higher efficiency of cannabinoid signaling at somatic versus dendritic synapses. Furthermore, chronic Δ9-tetrahydrocannabinol administration, which reduces cannabinoid efficacy on GABA release, evoked dramatic CB1-downregulation in a dose-dependent manner. Full receptor recovery required several weeks after cessation of Δ9-tetrahydrocannabinol treatment. These findings demonstrate that cell-type-specific nanoscale analysis of endogenous protein distribution is possible in brain circuits, and identify novel molecular properties controlling endocannabinoid signaling and cannabis-induced cognitive dysfunction.

Cdk5-dependent phosphorylation of liprinα1 mediates neuronal activity-dependent synapse development

“…STORM analysis enables the visualization of synaptic proteins in situ, as well as an extremely precise analysis of protein associations and distribution patterns (32,33). Similar to previous observations, we observed that PSD-95 was expressed as clusters of comparable size, with a mean principal length of 424.7 ± 177.2 nm and an auxiliary length of 282.8 ± 78.85 nm (34). )…”

Cannabinoids and Epilepsy

“…CB 1 Rs are most densely expressed at cortical and hippocampal presynaptic γ-aminobutyric acid (GABA)ergic presynaptic boutons, especially cholecystokinin-positive (CCK+) and parvalbumin-negative GABAergic interneurons [64][65][66]. Glutamatergic axon terminals in cortical and subcortical neurons contain fewer presynaptic CB1 receptors than GABAergic terminals [65,[67][68][69][70][71].…”

Variation in Carbohydrates between Cancer and Normal Cell Membranes Revealed by Super‐Resolution Fluorescence Imaging

“…Herein, in addition to common monosaccharides mentioned above, we also selected one common oligosaccharide (pentasaccharide sequence Galβ1‐4GlcNAcβ1‐2 (Galβ1‐4GlcNAcβ1‐6) Manα1‐R) as the investigated target, which is a complement and comparison to monosaccharides, as well as confirms that the results of monosaccharides can reflect ones of carbohydrate‐chains. Through using super‐resolution microscopy with a nanometer‐level resolution,17, 18, 19 we studied the changed distributions of these selected carbohydrates on cell membranes, showing an overall alterant distribution of carbohydrate‐related molecules (glycoproteins, glycolipids, and glycosaminoglycans) containing the same carbohydrate residues, as well as suggesting the changed organization of cell membrane. Herein, we revealed the distributed alterations of carbohydrates on cancer cell (both cultured and primary cells) membranes compared with normal cell (both cultured and primary cells) membranes.…”