ABSTRACT: Pathway analysis identifies altered mitochondrial metabolism, neurotransmission, structural pathways and complement cascade in retina/RPE/choroid in chick model of form-deprivation myopia
Project description:We investigated diurnal changes in gene expression in the retina and choroid at the onset of experimental myopia. We induced visual form deprivation myopia in young chicks, and isolated retinal and choroidal tissues separately in form- deprived and contralateral control eyes every 4 hours over a single 24-hour period.
Project description:We sequenced mRNA from 16 retina/RPE/choroid samples taken from the right eyes of male chicks across control, form-deprivation occlusion, and recovery from form deprivation conditions.
Project description:Following laboratory and clinical findings implicating circadian biology in the pathogenesis of myopia (nearsightedness), we examined gene expression in two crucial tissues controlling post-natal refractive development, the retina and choroid. Inducing unilateral visual form deprivation myopia in young chicks, a widely studied and validated model, we isolated retinal and choroidal tissues every 4 hours over a single day from myopic and contralateral control eyes during a period time when myopia progresses rapidly.
Project description:Microarray analysis was performed on retina/RPE/choroid samples taken from the right eyes of male chicks across control and recovery from form deprivation conditions.
Project description:One-day old white Leghorn chicks were housed in brooders with a 12 hr light:dark cycle, using General Electric chroma 50 fluorescent lighting with irradiance of approximately 50μW/cm2 at chick eye level. They received Purina Chick Chow food and water ad libitum. At one week of age and at the onset of the light phase, the chicks were anesthetized with inhalation ether, and a unilateral translucent white plastic goggle was glued to the periorbital feathers to induce ipsilateral form-deprivation myopia, alternating between the left or right eye. After either 6 hrs (n=8) or 3 days (n=8) of goggle wear, the chicks were killed by decapitation. The enucleated eyes were opened at the equator, and the retina/RPE was dissected together from both the goggled and control eyes. The tissues were individually frozen and stored in liquid nitrogen until processed Experiment Overall Design: Six biological replicates used for each: 3 day control retina, 3 day experimental, 6 hour control retina, and 6 hour experimental.
Project description:We sequenced mRNA from 34 retina/RPE/choroid samples taken from the right eyes of male chicks across a time-course of normal development or refractive error induction (defocus-induced myopia and hyperopia).
Project description:One-day old white Leghorn chicks were housed in brooders with a 12 hr light:dark cycle, using General Electric chroma 50 fluorescent lighting with irradiance of approximately 50μW/cm2 at chick eye level. They received Purina Chick Chow food and water ad libitum. At one week of age and at the onset of the light phase, the chicks were anesthetized with inhalation ether, and a unilateral translucent white plastic goggle was glued to the periorbital feathers to induce ipsilateral form-deprivation myopia, alternating between the left or right eye. After either 6 hrs (n=8) or 3 days (n=8) of goggle wear, the chicks were killed by decapitation. The enucleated eyes were opened at the equator, and the retina/RPE was dissected together from both the goggled and control eyes. The tissues were individually frozen and stored in liquid nitrogen until processed Keywords: Gene expression
Project description:Purpose: The complement system is closely linked to the pathogenesis of age-related macular degeneration (AMD). Several complement genes are expressed in retinal pigment epithelium (RPE), and complement proteins accumulate in drusen. Further, a common variant of complement factor H (CFH) confers increased risk of developing AMD. Because the mechanisms by which changes in the function of CFH influence development of AMD are unclear, we examined ocular complement expression as a consequence of age in control and CFH null mutant mice. Methods: Gene expression in neuroretinas and RPE/choroid from young and aged WT and Cfh-/- C57BL/6J mice was analysed by microarrays. Expression of a wide range of complement genes was compared to expression in splenocytes and in liver tissue by qRT-PCR. Results: An age-associated increased expression of complement, particularly C1q, C3 and Factor B, in the RPE/choroid coincided with increased expression of the negative regulators Cfh and Cd59a in the neuroretina. Young mice deficient in CFH expressed Cd59a similar to WT, but failed to upregulate Cd59a expression with age. Both hepatic and splenic expression of Cd59a increased with age regardless of Cfh genotype. Conclusions: While the connection between CFH deficiency and failure to up-regulate CD59a remains unknown, these results suggest that expression of CD59 is tissue-specific and that neuroretinal regulation depends on CFH. This could contribute to the visual functional deficits and morphological changes in the Cfh-/- mouse retina that occur with age, and further suggests that deficient neuroretinal regulation of complement could represent an early event in AMD. Gene expression in neuroretinas and RPE/choroid from young and aged WT and Cfh-/- mice, 4 biological replicates in each group.
