Media type: E-Article Title: Expression and cellular localization of the voltage‐gated calcium channel α2δ3 in the rodent retina Contributor: Pérez de Sevilla Müller, Luis; Sargoy, Allison; Fernández‐Sánchez, Laura; Rodriguez, Allen; Liu, Janelle; Cuenca, Nicolás; Brecha, Nicholas imprint: Wiley, 2015 Published in: Journal of Comparative Neurology Language: English DOI: 10.1002/cne.23825 ISSN: 0021-9967; 1096-9861 Keywords: General Neuroscience Origination: Footnote: Description: <jats:title>ABSTRACT</jats:title><jats:p>High‐voltage‐activated calcium channels are hetero‐oligomeric protein complexes that mediate multiple cellular processes, including the influx of extracellular Ca<jats:sup>2+</jats:sup>, neurotransmitter release, gene transcription, and synaptic plasticity. These channels consist of a primary α<jats:sub>1</jats:sub> pore‐forming subunit, which is associated with an extracellular α<jats:sub>2</jats:sub>δ subunit and an intracellular β auxiliary subunit, which alter the gating properties and trafficking of the calcium channel. The cellular localization of the α<jats:sub>2</jats:sub>δ<jats:sub>3</jats:sub> 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 α<jats:sub>2</jats:sub>δ<jats:sub>3</jats:sub> 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 α<jats:sub>2</jats:sub>δ<jats:sub>3</jats:sub> 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. α<jats:sub>2</jats:sub>δ<jats:sub>3</jats:sub> immunoreactivity was localized to multiple cell types, including ganglion, amacrine, and bipolar cells and photoreceptors, but not horizontal cells. The expression of the α<jats:sub>2</jats:sub>δ<jats:sub>3</jats:sub> 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.</jats:p>