Expression and cellular localization of the voltage‐gated calcium channel α2δ3 in the rodent retina. Issue 10 (10th March 2015)

• Record Type: Journal Article
• Authors: Pérez de Sevilla Müller, Luis; Sargoy, Allison; Fernández‐Sánchez, Laura; Rodriguez, Allen; Liu, Janelle; Cuenca, Nicolás; Brecha, Nicholas
• Is Part Of: Journal of comparative neurology. Volume 523:Issue 10(2015:Jun. 15)
• Page Start: 1443
• Page End: 1460
• Publication Date: 2015-03-10
• Subjects: calcium channel -- retina -- α2δ3 subunit -- amacrine cell -- ganglion cell -- photoreceptor; Comparative neurobiology -- Periodicals; Neurology -- Periodicals; 616
• DOI: 10.1002/cne.23751
• Languages: English
• ISSNs: 0021-9967

Abstract

ABSTRACT: High‐voltage‐activated calcium channels are hetero‐oligomeric protein complexes that mediate multiple cellular processes, including the influx of extracellular Ca 2+, neurotransmitter release, gene transcription, and synaptic plasticity. These channels consist of a primary α1 pore‐forming subunit, which is associated with an extracellular α2 δ subunit and an intracellular β auxiliary subunit, which alter the gating properties and trafficking of the calcium channel. The cellular localization of the α2 δ3 subunit in the mouse and rat retina is unknown. In this study using RT‐PCR, a single band at ∼305 bp corresponding to the predicted size of the α2 δ3 subunit fragment was found in mouse and rat retina and brain homogenates. Western blotting of rodent retina and brain homogenates showed a single 123‐kDa band. Immunohistochemistry with an affinity‐purified antibody to the α2 δ3 subunit revealed immunoreactive cell bodies in the ganglion cell layer and inner nuclear layer and immunoreactive processes in the inner plexiform layer and the outer plexiform layer. α2 δ3 immunoreactivity was localized to multiple cell types, including ganglion, amacrine, and bipolar cells and photoreceptors, but not horizontal cells. The expression of the α2 δ3 calcium channel subunit to multiple cell types suggests that this subunit participates widely in Ca‐channel‐mediated signaling in the retina. J. Comp. Neurol. 523:1443–1460, 2015. © 2015 Wiley Periodicals, Inc. Abstract : α2 δ3 immunoreactivity (green) was expressed in RBPMS (magenta)‐containing cells in the mouse GCL. RBPMS is a selective marker for RGCs. Arrows indicate cells containing α2 δ3 immunoreactivity and no RBPMS immunoreactivity, indicating that they are displaced amacrine cells.