title: Distribution of voltage gated calcium channel β subunits in the mouse retina.
abstract: Voltage gated calcium channels (VGCCs) are essential to neuronal excitation and signal transduction. They are multimeric in structure and comprised of an alpha subunit that functions as a calcium pore and two additional subunits: an alpha2delta subunit and a cytoplasmic beta subunit. To better understand the role of VGCCs in the retina we used immunohistochemical methods to determine the distribution of VGCC β subunits in normal and mutant mice. To verify the specificity of each antibody and to examine the potential for subunit redistribution when beta subunit expression is perturbed, we used 4 mutant mouse lines that each lack a specific β subunit isoform (β(1)-β(4)). We found the β(1) subunit distributed on cell bodies in the inner nuclear layer (INL) and on processes within both the inner and outer limiting membrane; the β(2) subunit localized to the outer plexiform layer (OPL) and inner plexiform layer (IPL); the β(3) subunit was localized to three narrow and distinct bands within the IPL; the β(4) subunit was localized to three diffuse bands within the IPL. Loss of one β subunit affected labeling intensity but not general distribution patterns of other β subunits. It is likely that VGCCs critical for retinal signal transmission are comprised of the β(2) subunit in the OPL and any of the 4 β subunits in the IPL. Our results suggest that within the OPL the α(1F) subunit pairs predominantly with the β(2) subunit while within the IPL it may pair with either any β subunit.
authors.affiliation: Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH 44106, USA. sherry.ball@case.edu
authors.forename: Sherry L
authors.initials: SL
authors.lastname: Ball
authors.forename: Maureen W
authors.initials: MW
authors.lastname: McEnery
authors.forename: Anne Marie R
authors.initials: AM
authors.lastname: Yunker
authors.forename: Hee-Sup
authors.initials: HS
authors.lastname: Shin
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Gregg
mesh_terms: D000818:Animals; D064032:Calbindin 2; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D021122:Protein Subunits / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D064030:S100 Calcium Binding Protein G / Q000378:metabolism
chemical_list: D064032:Calbindin 2; D020746:Calcium Channels, L-Type; D021122:Protein Subunits; D064030:S100 Calcium Binding Protein G; D002795:Choline O-Acetyltransferase