vision/eye
• retinal dysplasia, with highly variable severity
• from P21 onwards, some retinas show one or two dysplastic regions in either the central or dorsal retina; incidence of this phenotype is higher in older mice
• retinal dysplasia is never seen in the retinal pigment epithelium and no difference in the thickness of either the outer or the inner nuclear layers
• however, no defects in optic fissure closure are seen
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• the number of cones is decreased in ventral retinas, affecting both S-opsin and M-opsin labelled cones
• S-opsin labelled cones are also severely decreased in the mid-dorsal and the central retina
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• adults show progressive cone photoreceptor degeneration
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• mice show a persistence of a population of proliferative cells in P6 retinas but not at P11, indicating that retinal progenitor cells show delayed cell-cycle exit in postnatal mice, eventually exiting the cell cycle between P6 and P11
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• GFAP expression is increased in 12-month-old retina indicating reactive gliosis
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• mice show a reduction of the cone-mediated ERG response
• however, scotopic a- and b-waves are similar to controls at all stages, indicating normal rod photoreceptor function
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• photopic b-wave amplitude is depressed in 12-month-old mice at high intensity stimuli
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nervous system
• the number of cones is decreased in ventral retinas, affecting both S-opsin and M-opsin labelled cones
• S-opsin labelled cones are also severely decreased in the mid-dorsal and the central retina
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• adults show progressive cone photoreceptor degeneration
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• 12-month-old retina shows a decrease in the number of Ribeye+ puncta, representing presynaptic ribbons, in photoreceptor terminals
• some ribbons do not exhibit the typical horseshoe shape suggesting compromised synapse integrity
• however, ribbons with proper shape are still present close to dendritic process of the rod-bipolar cell postsynaptic terminals, indicating a correct synaptic connection between rod photoreceptor and rod-bipolar cells
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• marker analysis indicates altered Muller cell homeostatic function in aged mice
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Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
cone dystrophy | DOID:0050795 | J:304126 |