title: Amyloid precursor protein is required for normal function of the rod and cone pathways in the mouse retina.
abstract: Amyloid precursor protein (APP) is a transmembrane glycoprotein frequently studied for its role in Alzheimer's disease. Our recent study in APP knockout (KO) mice identified an important role for APP in modulating normal neuronal development in the retina. However the role APP plays in the adult retina and whether it is required for vision is unknown. In this study we evaluated the role of APP in retinal function and morphology comparing adult wildtype (WT) and APP-KO mice. APP was expressed on neuronal cells of the inner retina, including horizontal, cone bipolar, amacrine and ganglion cells in WT mice. The function of the retina was assessed using the electroretinogram and although the rod photoreceptor responses were similar in APP-KO and WT mice, the post-photoreceptor, inner retinal responses of both the rod and cone pathways were reduced in APP-KO mice. These changes in inner retinal function did not translate to a substantial change in visual acuity as assessed using the optokinetic response or to changes in the gross cellular structure of the retina. These findings indicate that APP is not required for basic visual function, but that it is involved in modulating inner retinal circuitry.
authors.affiliation: Department of Anatomy & Cell Biology, The University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Tracy
authors.initials: T
authors.lastname: Ho
authors.forename: Kirstan A
authors.initials: KA
authors.lastname: Vessey
authors.forename: Roberto
authors.initials: R
authors.lastname: Cappai
authors.forename: Virginie
authors.initials: V
authors.lastname: Dinet
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mascarelli
authors.forename: Giuseppe D
authors.initials: GD
authors.lastname: Ciccotosto
authors.forename: Erica L
authors.initials: EL
authors.lastname: Fletcher
mesh_terms: D016564:Amyloid beta-Protein Precursor / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D004596:Electroretinography; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D012160:Retina / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D016564:Amyloid beta-Protein Precursor