vision/eye
• retinal ganglion cells grown in culture exhibit abnormal neurite arborization, with shorter axons and increased numbers of neurites, although the length of the dendritic projections is unaltered
• however, no differences in retinal ganglion cell dendrite length, dendritic field area, or number of primary dendrites are seen in vitro
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• photoreceptors exhibit disordered and loosely stacked disks
• photoreceptor outer segments show double membrane vesicles that disrupt the stacking of disks
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• photoreceptor outer segment length is longer
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• retinas show longer rod outer segments along the dorsal retina of the retina
• however, the length of rod outer segments and cone sheaths are normal in the ventral retina
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• outer segments appear disarrayed
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• S-opsin and M-opsin are detected up to the middle of the cone sheath
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• the number of cones is decreased in 2-month-old mice and is diminished in 11- to 18-month-old mice
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• retinal microvilli are disarrayed and do not wrap the outer segment tips, indicating defective phagocytosis
• distribution of phagosomes in retinal pigment cells of old mice is altered and the number of basal endosomes is increased
• total number of lysosomes is increased close to two-fold in the retinal pigment epithelium
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• retinas exhibit a wavy outer nuclear layer, with zones with fewer nuclei and others with an increased number of nuclei
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• decrease in the number of the nuclei rows in the outer nuclear layer on both sides of the retina
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• mice show severe layer organization defects
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• the number of photoreceptor nuclei rows is decreased along the whole retina, indicating severe retinal degeneration
• retinal degeneration is seen by 18 months of age
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• retinas are thicker with enlargement of the inner nuclear and plexiform layers in half of mice and appear thinner in the other half of mice, indicating irregular thickness along the retina
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• retinas show an increase in GFAP expression indicating reactive gliosis
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• oscillatory potential responses, reflecting the synaptic activity of retinal ganglion cells and amacrine cells, are decreased
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• scotopic and photopic b-wave amplitudes are decreased and postsynaptic activity (b-wave mix) is decreased in mice over 18 months of age, but not in 6-10-month-old mice
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• ERG shows that cone activity is diminished in mice over 18 months of age
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• ERG shows that rod activity is diminished in mice over 18 months of age
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• progressive vision impairment
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pigmentation
• retinal microvilli are disarrayed and do not wrap the outer segment tips, indicating defective phagocytosis
• distribution of phagosomes in retinal pigment cells of old mice is altered and the number of basal endosomes is increased
• total number of lysosomes is increased close to two-fold in the retinal pigment epithelium
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nervous system
• retinal ganglion cells grown in culture exhibit abnormal neurite arborization, with shorter axons and increased numbers of neurites, although the length of the dendritic projections is unaltered
• however, no differences in retinal ganglion cell dendrite length, dendritic field area, or number of primary dendrites are seen in vitro
|
• photoreceptors exhibit disordered and loosely stacked disks
• photoreceptor outer segments show double membrane vesicles that disrupt the stacking of disks
|
• photoreceptor outer segment length is longer
|
• retinas show longer rod outer segments along the dorsal retina of the retina
• however, the length of rod outer segments and cone sheaths are normal in the ventral retina
|
• outer segments appear disarrayed
|
• S-opsin and M-opsin are detected up to the middle of the cone sheath
|
• the number of cones is decreased in 2-month-old mice and is diminished in 11- to 18-month-old mice
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
retinitis pigmentosa 26 | DOID:0110368 |
OMIM:608380 |
J:292626 |