title: High-resolution optical imaging of zebrafish larval ribbon synapse protein RIBEYE, RIM2, and CaV 1.4 by stimulation emission depletion microscopy.
abstract: The synaptic ribbon is a unique presynaptic structure with an intricate morphology in photoreceptors. Because of the resolution limit in conventional fluorescence microscopy, investigating ribbon protein locations has been challenging, especially in the early development stages of model animals. Here, we used stimulated emission depletion microscopy, a super-resolution imaging technique, to look at retina sections in 4 days post-fertilization (dpf) zebrafish. We observed that in photoreceptor cells, RIBEYE and RIM2 are expressed along the synaptic ribbon, with RIM2 consistently located inside of the horseshoe-shaped synaptic ribbon structure with RIBEYE located on the outside. The L-type calcium channel subunit, CACNA1F, exhibited small spot-like staining beneath the RIM2 and RIBEYE structures. Using morpholino antisense oligonucleotides to knock down RIBEYE expression, we observed fewer and shorter ribbons in the photoreceptor outer plexiform layers of 4 dpf fish retina as well as a reduction in RIM2 expression. The clustering of CACNA1F in these blind fish was no longer observed, but instead showed a diffuse expression in the photoreceptor terminal.
authors: Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA.
authors: Caixia
authors: C
authors: Lv
authors: Travis J
authors: TJ
authors: Gould
authors: Joerg
authors: J
authors: Bewersdorf
authors: David
authors: D
authors: Zenisek
mesh_terms: D000818:Animals; D020746:Calcium Channels, L-Type / Q000235:genetics / Q000378:metabolism*; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism*; D007814:Larva / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008853:Microscopy / Q000379:methods*; D010786:Photoreceptor Cells / Q000737:chemistry / Q000378:metabolism; D021381:Protein Transport; D012160:Retina / Q000737:chemistry / Q000196:embryology / Q000378:metabolism*; D013569:Synapses / Q000737:chemistry / Q000378:metabolism*; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D020746:Calcium Channels, L-Type; D005136:Eye Proteins; D029961:Zebrafish Proteins; C577848:cacna1fb protein, zebrafish; C577847:ctbp2a protein, zebrafish