title: L-ferritin binding to scara5: a new iron traffic pathway potentially implicated in retinopathy.
abstract: Iron is essential in the retina because the heme-containing enzyme guanylate cyclase modulates phototransduction in rods and cones. Transferrin endocytosis is the classical pathway for obtaining iron from the blood circulation in the retina. However, the iron storage protein ferritin has been also recently proposed as an iron carrier. In this study, the presence of Scara5 and its binding to L-ferritin was investigated in the retina. Our results showed that Scara5, the specific receptor for L-ferritin, was expressed in mouse and human retinas in many cell types, including endothelial cells. Furthermore, we showed that intravenously injected ferritin crossed the blood retinal barrier through L-ferritin binding to Scara5 in endothelial cells. Thus, suggesting the existence of a new pathway for iron delivery and trafficking in the retina. In a murine model of photoreceptor degeneration, Scara5 was downregulated, pointing out this receptor as a potential player implicated in retinopathy and also as a possible therapeutic target.
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Department of Morphology and Function, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Luísa
authors.initials: L
authors.lastname: Mendes-Jorge
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Ramos
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: Andreia
authors.initials: A
authors.lastname: Valença
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Animal Health and Anatomy, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Mariana
authors.initials: M
authors.lastname: López-Luppo
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal.
authors.forename: Virgínia Maria Rico
authors.initials: VM
authors.lastname: Pires
authors.affiliation: Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Joana
authors.initials: J
authors.lastname: Catita
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Animal Health and Anatomy, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Victor
authors.initials: V
authors.lastname: Nacher
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Animal Health and Anatomy, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Marc
authors.initials: M
authors.lastname: Navarro
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Animal Health and Anatomy, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Carretero
authors.affiliation: Department of Morphological Sciences, School of Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Rodriguez-Baeza
authors.affiliation: Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa, Lisbon, Portugal; Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Animal Health and Anatomy, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Barcelona, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Ruberte
mesh_terms: D000818:Animals; D001692:Biological Transport; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D005293:Ferritins / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D005786:Gene Expression Regulation; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D051379:Mice; D010786:Photoreceptor Cells / Q000378:metabolism / Q000473:pathology; D011485:Protein Binding; D021381:Protein Transport; D012160:Retina / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D012162:Retinal Degeneration / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012164:Retinal Diseases / Q000378:metabolism / Q000473:pathology; D055351:Retinal Neurons / Q000378:metabolism; D051117:Scavenger Receptors, Class A / Q000235:genetics / Q000378:metabolism*
chemical_list: C569833:SCARA5 protein, human; D051117:Scavenger Receptors, Class A; D005293:Ferritins; D007501:Iron