title: CRB2 acts as a modifying factor of CRB1-related retinal dystrophies in mice.
abstract: Mutations in the CRB1 gene lead to retinal dystrophies ranging from Leber congenital amaurosis (LCA) to early-onset retinitis pigmentosa (RP), due to developmental defects or loss of adhesion between photoreceptors and Müller glia cells, respectively. Whereas over 150 mutations have been found, no clear genotype-phenotype correlation has been established. Mouse Crb1 knockout retinas show a mild phenotype limited to the inferior quadrant, whereas Crb2 knockout retinas display a severe degeneration throughout the retina mimicking the phenotype observed in RP patients associated with CRB1 mutations. Crb1Crb2 double mutant retinas have severe developmental defects similar to the phenotype observed in LCA patients associated with CRB1 mutations. Therefore, CRB2 is a candidate modifying gene of human CRB1-related retinal dystrophy. In this study, we studied the cellular localization of CRB1 and CRB2 in human retina and tested the influence of the Crb2 gene allele on Crb1-retinal dystrophies in mice. We found that in contrast to mice, in the human retina CRB1 protein was expressed at the subapical region in photoreceptors and Müller glia cells, and CRB2 only in Müller glia cells. Genetic ablation of one allele of Crb2 in heterozygote Crb1(+/-) retinas induced a mild retinal phenotype, but in homozygote Crb1 knockout mice lead to an early and severe phenotype limited to the entire inferior retina. Our data provide mechanistic insight for CRB1-related LCA and RP.
authors.affiliation: Department of Neuromedical Genetics.
authors.forename: Lucie P
authors.initials: LP
authors.lastname: Pellissier
authors.affiliation: Department of Neuromedical Genetics.
authors.forename: Ditte M S
authors.initials: DM
authors.lastname: Lundvig
authors.affiliation: Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, Eberhard Karls University of Tübingen, Tübingen D-72076, Germany and.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Tanimoto
authors.affiliation: Department of Retinal Signal Processing, The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam 1105 BA, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Klooster
authors.affiliation: Department of Neuromedical Genetics.
authors.forename: Rogier M
authors.initials: RM
authors.lastname: Vos
authors.affiliation: Aix-Marseille Université, CNRS, UMR 7288, Developmental Biology Institute of Marseille (IBDM), Case 907, Marseille, Cedex 09 13288, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Richard
authors.affiliation: Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, Eberhard Karls University of Tübingen, Tübingen D-72076, Germany and.
authors.forename: Vithiyanjali
authors.initials: V
authors.lastname: Sothilingam
authors.affiliation: Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, Eberhard Karls University of Tübingen, Tübingen D-72076, Germany and.
authors.forename: Marina
authors.initials: M
authors.lastname: Garcia Garrido
authors.affiliation: Aix-Marseille Université, CNRS, UMR 7288, Developmental Biology Institute of Marseille (IBDM), Case 907, Marseille, Cedex 09 13288, France.
authors.forename: André
authors.initials: A
authors.lastname: Le Bivic
authors.affiliation: Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, Eberhard Karls University of Tübingen, Tübingen D-72076, Germany and.
authors.forename: Mathias W
authors.initials: MW
authors.lastname: Seeliger
authors.affiliation: Department of Neuromedical Genetics, j.wijnholds@nin.knaw.nl.
authors.forename: Jan
authors.initials: J
authors.lastname: Wijnholds
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D063928:Ependymoglial Cells / Q000378:metabolism*; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism*; D055786:Gene Knockout Techniques; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010786:Photoreceptor Cells / Q000378:metabolism; D058499:Retinal Dystrophies / Q000378:metabolism*
chemical_list: C448939:CRB1 protein, human; C492531:CRB2 protein, human; D002352:Carrier Proteins; C453730:Crb1 protein, mouse; C568885:Crb2 protein, mouse; D005136:Eye Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins