title: Association of shank 1A scaffolding protein with cone photoreceptor terminals in the mammalian retina.
abstract: Photoreceptor terminals contain post-synaptic density (PSD) proteins e.g., PSD-95/PSD-93, but their role at photoreceptor synapses is not known. PSDs are generally restricted to post-synaptic boutons in central neurons and form scaffolding with multiple proteins that have structural and functional roles in neuronal signaling. The Shank family of proteins (Shank 1-3) functions as putative anchoring proteins for PSDs and is involved in the organization of cytoskeletal/signaling complexes in neurons. Specifically, Shank 1 is restricted to neurons and interacts with both receptors and signaling molecules at central neurons to regulate plasticity. However, it is not known whether Shank 1 is expressed at photoreceptor terminals. In this study we have investigated Shank 1A localization in the outer retina at photoreceptor terminals. We find that Shank 1A is expressed presynaptically in cone pedicles, but not rod spherules, and it is absent from mice in which the Shank 1 gene is deleted. Shank 1A co-localizes with PSD-95, peanut agglutinin, a marker of cone terminals, and glycogen phosphorylase, a cone specific marker. These findings provide convincing evidence for Shank 1A expression in both the inner and outer plexiform layers, and indicate a potential role for PSD-95/Shank 1 complexes at cone synapses in the outer retina.
authors.affiliation: Department of Ophthalmology, University of Missouri-Kansas City, School of Medicine, Kansas City, Missouri, United States of America. stellas@umkc.edu
authors.forename: Salvatore L
authors.initials: SL
authors.lastname: Stella
authors.forename: Alejandro
authors.initials: A
authors.lastname: Vila
authors.forename: Albert Y
authors.initials: AY
authors.lastname: Hung
authors.forename: Michael E
authors.initials: ME
authors.lastname: Rome
authors.forename: Uyenchi
authors.initials: U
authors.lastname: Huynh
authors.forename: Morgan
authors.initials: M
authors.lastname: Sheng
authors.forename: Hans-Juergen
authors.initials: HJ
authors.lastname: Kreienkamp
authors.forename: Nicholas C
authors.initials: NC
authors.lastname: Brecha
mesh_terms: D000818:Animals; D000076122:Disks Large Homolog 4 Protein; D017353:Gene Deletion; D051528:Guanylate Kinases / Q000378:metabolism; D008322:Mammals / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009928:Organ Specificity; D019887:Peanut Agglutinin / Q000378:metabolism; D011485:Protein Binding; D017949:Retinal Cone Photoreceptor Cells / Q000166:cytology / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism; D014909:Wheat Germ Agglutinins / Q000378:metabolism
chemical_list: D000076122:Disks Large Homolog 4 Protein; C501447:Dlg4 protein, mouse; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D019887:Peanut Agglutinin; C512412:SHANK1 protein, mouse; D014909:Wheat Germ Agglutinins; D051528:Guanylate Kinases