Dataset Information

Differential neuroglycan C expression during retinal degeneration in Rpe65-/- mice.

ABSTRACT: PURPOSE: An increased mRNA expression of the genes coding for the extracellular matrix proteins neuroglycan C (NGC), interphotoreceptor matrix proteoglycan 2 (IMPG2), and CD44 antigen (CD44) has been observed during retinal degeneration in mice with a targeted disruption of the Rpe65 gene (Rpe65-/- mouse). To validate these data, we analyzed this differential expression in more detail by characterizing retinal NGC mRNA isoform and protein expression during disease progression. METHODS: Retinas from C57/Bl6 wild-type and Rpe65-/- mice, ranging 2 to 18 months of age, were used. NGC, IMPG2, and CD44 mRNA expression was assessed by oligonucleotide microarray, quantitative PCR, and in situ hybridization. Retinal NGC protein expression was analyzed by western blot and immunohistochemistry. RESULTS: As measured by quantitative PCR, mRNA expression of NGC and CD44 was induced by about 2 fold to 3 fold at all time points in Rpe65-/- retinas, whereas initially 4 fold elevated IMPG2 mRNA levels progressively declined. NGC and IMPG2 mRNAs were expressed in the ganglion cell layer, the inner nuclear layer, and at the outer limiting membrane. NGC mRNA was also detected in retinal pigment epithelium cells (RPE), where its mRNA expression was not induced during retinal degeneration. NGC-I was the major isoform detected in the retina and the RPE, whereas NGC-III was barely detected and NGC-II could not be assessed. NGC protein expression was at its highest levels on the apical membrane of the RPE. NGC protein levels were induced in retinas from 2- and 4-month-old Rpe65-/- mice, and an increased amount of the activity-cleaved NGC ectodomain containing an epidermal growth factor (EGF)-like domain was detected. CONCLUSIONS: During retinal degeneration in Rpe65-/- mice, NGC expression is induced in the neural retina, but not in the RPE, where NGC is expressed at highest levels.

SUBMITTER: Escher P

PROVIDER: S-EPMC2592529 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Differential neuroglycan C expression during retinal degeneration in Rpe65-/- mice.

Escher Pascal P Cottet Sandra S Aono Saichiko S Oohira Atsuhiko A Schorderet Daniel F DF

Molecular vision 20081126

<h4>Purpose</h4>An increased mRNA expression of the genes coding for the extracellular matrix proteins neuroglycan C (NGC), interphotoreceptor matrix proteoglycan 2 (IMPG2), and CD44 antigen (CD44) has been observed during retinal degeneration in mice with a targeted disruption of the Rpe65 gene (Rpe65-/- mouse). To validate these data, we analyzed this differential expression in more detail by characterizing retinal NGC mRNA isoform and protein expression during disease progression.<h4>Methods< ...[more]

PMID: 19050768

Similar Datasets

Project description:PURPOSE:Mutations of the gene encoding RPE65 cause Leber congenital amaurosis (LCA) retinitis pigmentosa (RP). The optical coherence tomography (OCT) is increasingly utilized to noninvasively evaluate various types of retinal diseases, including RP. The present study was conducted to characterize the OCT findings of the RPE65-/- mice-an animal model of LCA and RP-in relation to the morphological features based on histological and electron microscopic findings as well as electroretinography (ERG) features. MATERIALS AND METHODS:RPE65-/- mice were employed as a model of retinal degeneration. C57BL/6J mice were used as a wild-type control. OCT was performed on the RPE65-/- mice from postnatal day (P) 22 to 170. The longitudinal changes in the OCT images and fundus pictures were analyzed both qualitatively and quantitatively in comparison to those of C57BL/6J mice. The OCT images were also compared to the histological and electron microscopic findings. Full field combined rod and cone ERG was performed to analyze the relationship between morphology based on OCT and the amplitudes of the a- and b-waves. RESULTS:In the RPE65-/- mice, the photoreceptor rod and cone layer appeared as a diffuse hyperreflective zone contiguous with the inner segment ellipsoid zone (IS-EZ) on OCT, even on P22, whereas the IS-EZ and interdigitation zone were clearly identified in the age-matched C57BL/6J mice. The histological analyses revealed that the regular arrangement of the photoreceptor inner and outer segments was gradually lost in the RPE65-/- mice. On electron microscopy, most of the rod outer segments were degenerated from P21 to P35, whereas outer segments became variably shorter after P49 although ultrastructure appeared to normalize. The thickness of the outer nuclear layer of RPE65-/- mice was slowly and progressively reduced in comparison to C57BL/6J mice. Although the thickness of the inner and outer segment layer of RPE65-/- mice was significantly decreased in comparison to C57BL/6J mice, the change was not progressive, at least until P170. Even at P35, the amplitudes of both a- and b-waves on ERG were severely deteriorated in comparison to those of C57BL/6J mice. Mottled depigmented spots appeared throughout the fundus in RPE65-/- mice after P72, and were detected as hyperreflective deposits under the retinal pigment epithelium on OCT. DISCUSSION:The pathological changes in the inner and outer segments layer of RPE65-/- mice were identified as diffuse hyperreflective changes on OCT. The rod outer segments showed degeneration in the early postnatal periods but became morphologically normalized in the disc structure after P49, although the sizes of the length of the rod outer segments were variable. OCT could not qualitatively differentiate the early degeneration of rods from the late variability in size of rods. Although the morphology of the photoreceptor outer segments was relatively preserved in the RPE65-/- mice, the amplitudes of ERG were severely disturbed. These structural and functional deficits may be derived from the defective supply of 11-cis-retinol to the photoreceptors.

Dataset Information

Differential neuroglycan C expression during retinal degeneration in Rpe65-/- mice.

Publications

Differential neuroglycan C expression during retinal degeneration in Rpe65-/- mice.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets