title: Fragile X Mental Retardation Protein expression in the retina is regulated by light.
abstract: Fragile X Mental Retardation Protein (FMRP) is a RNA-binding protein that modulates protein synthesis at the synapse and its function is regulated by glutamate. The retina is the first structure that participates in vision, and uses glutamate to transduce electromagnetic signals from light to electrochemical signals to neurons. FMRP has been previously detected in the retina, but its localization has not been studied yet. In this work, our objectives were to describe the localization of FMRP in the retina, to determine whether different exposure to dark or light stimulus alters FMRP expression in the retina, and to compare the pattern in two different species, the mouse and chick. We found that both FMRP mRNA and protein are expressed in the retina. By immunohistochemistry analysis we found that both mouse and chick present similar FMRP expression localized mainly in both plexiform layers and the inner retina. It was also observed that FMRP is down-regulated by 24 h dark adaptation compared to its expression in the retina of animals that were exposed to light for 1 h after 24 h in the dark. We conclude that FMRP is likely to participate in retinal physiology, since its expression changes with light exposure. In addition, the expression pattern and regulation by light of FMRP seems well conserved since it was similar in both mouse and chick.
authors.affiliation: Neurosciences Program, Biology Institute, Federal Fluminense University, Niterói, Rio de Janeiro, Brazil.
authors.forename: E M
authors.initials: EM
authors.lastname: Guimarães-Souza
authors.affiliation: Genetic Department, Regional Hospital, Orléans, France; UMR7355, CNRS, Orléans, France; Experimental and Molecular Immunology and Neurogenetics, CNRS, University of Orléans, Orléans, France.
authors.forename: O
authors.initials: O
authors.lastname: Perche
authors.affiliation: Department of Physiology & Pharmacology, Oregon Health &Science University, Portland, OR, USA.
authors.forename: C W
authors.initials: CW
authors.lastname: Morgans
authors.affiliation: Department of Physiology & Pharmacology, Oregon Health &Science University, Portland, OR, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Duvoisin
authors.affiliation: Neurosciences Program, Biology Institute, Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. Electronic address: karincalaza@gmail.com.
authors.forename: K C
authors.initials: KC
authors.lastname: Calaza
mesh_terms: D000818:Animals; D002645:Chickens; D003623:Dark Adaptation / Q000502:physiology*; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000096:biosynthesis / Q000235:genetics* / Q000528:radiation effects; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D008027:Light; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012313:RNA / Q000235:genetics*; D012160:Retina / Q000378:metabolism*
chemical_list: D051860:Fragile X Messenger Ribonucleoprotein 1; D012313:RNA; C497684:Fmr1 protein, mouse
keywords: FMRP; Metabotropic glutamate receptor; Plasticity; Vision; mGluR