Phenotypes associated with this allele
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gucy2etm1Gar mutation
(1 available);
any
Gucy2e mutation
(45 available)
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Ultrastructure of wild type and degenerative Gucy2etm1Gar/Gucy2etm1Gar cone outer segments
vision/eye
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• at distal connecting cilia, membrane components are partitioned into layered stacks
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• apical inner segments of cones appear retracted from connecting cilia and surrounded by extracellular blebs
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• at 2 months of age, cone outer segments (COS) in retinas are extremely disorganized
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• in severely degenerated cases, membranes are detached
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• sensitivity of rods to light (half-saturating flash intensity of 13.6 photons/um2) is 3.5-fold higher than wild-type
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• scotopic a- and b-wave amplitudes in 4-6 week old mice are significantly reduced compared to wild-type responses
• after exposure to high intensity light, followed by 1 hour of dark adaptation, a-wave amplitude recovery is delayed relative to wild-type, with only 30% recovery
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nervous system
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• at distal connecting cilia, membrane components are partitioned into layered stacks
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• apical inner segments of cones appear retracted from connecting cilia and surrounded by extracellular blebs
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• at 2 months of age, cone outer segments (COS) in retinas are extremely disorganized
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gucy2etm1Gar mutation
(1 available);
any
Gucy2e mutation
(45 available)
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vision/eye
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• by 5 weeks of age, number of identifiable cones is dramatically reduced
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• cells degenerate rapidly at 4-5 weeks of age, with few surviving at late stages
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• by 1 month of age, electroretinograms (ERG) of mutant mice are abnormal
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• at one month of age, cone responses to flashes in rod-saturating background are barely detectable
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• rod a-wave and b-wave of ERG are severely reduced at one month of age
• flash response from a rod demonstrates increased time-to-peak before decaying more rapidly than in controls; rods have a higher sensitivity than wild-type
• rods show oscillations during and after recovery from a light flash
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nervous system
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• by 5 weeks of age, number of identifiable cones is dramatically reduced
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• cells degenerate rapidly at 4-5 weeks of age, with few surviving at late stages
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vision/eye
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• 6 month old mice have fewer cones in the inferior versus superior retinas
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• outer nuclear layer (ONL) is 28% thinner than in single Nrl homozygotes at 6 months of age
• treatment with an adenovirus expressing Gucy2e results in cone preservation with increased ONL thickness
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• ERG indicates no discernible wave forms, with no M-cone or S-cone responses
• subretinal injection of an adenovirus expressing Gucy2e at around P41, but not at P18, fully restores retinal function and useful vision over the long-term
• mice treated with an adenovirus expressing human GUCY2D at P40 exhibit restored retinal function
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behavior/neurological
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• visually guided behavior testing (optokinetic reflex) shows decreased cone-mediated spatial frequency thresholds at 6 months of age
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homeostasis/metabolism
nervous system
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• 6 month old mice have fewer cones in the inferior versus superior retinas
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gucy2etm1Gar mutation
(1 available);
any
Gucy2e mutation
(45 available)
Gucy2ftm1Wbae mutation
(0 available);
any
Gucy2f mutation
(4 available)
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Abnormal rod outer segments in Gucy2etm1Gar/Gucy2etm1Gar Gucy2ftm1Wbae/Gucy2ftm1Wbae mice
vision/eye
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• retinas have slightly decreased cone numbers relative to controls
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• at 2 months of age, outer segment lengths are ~50-70% of normal
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• cone cell remnants are identified in the retina, but outer segments are absent
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• cone degeneration is most severe inferior to the optic nerve
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• complete lack of cGMP
• rods are surrounded by blebs in interphotoreceptor matrix
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• at 6 months of age, rod outer segments are severely reduced in superior/inferior and nasal/temporal quadrants
• in retina, rod outer segments are shorter and narrower than in wild-type, and appear banded by alternating regions of dense membrane layers and lumen-containing tubules
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• at 6 months of age, outer nuclear layer (ONL) contains only 4-6 rows of nuclei
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• scotopic electroretinographic responses are absent in all double homozygotes
• no detectable light-sensitive current is detectable in rods
• after exposure to high intensity light, followed by 1 hour of dark adaptation, a-wave amplitude recovery is completely absent in mutants compared to 70% recovery in wild-type
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nervous system
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• retinas have slightly decreased cone numbers relative to controls
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• at 2 months of age, outer segment lengths are ~50-70% of normal
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• cone cell remnants are identified in the retina, but outer segments are absent
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• cone degeneration is most severe inferior to the optic nerve
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• complete lack of cGMP
• rods are surrounded by blebs in interphotoreceptor matrix
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• at 6 months of age, rod outer segments are severely reduced in superior/inferior and nasal/temporal quadrants
• in retina, rod outer segments are shorter and narrower than in wild-type, and appear banded by alternating regions of dense membrane layers and lumen-containing tubules
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Analysis Tools