Phenotypes associated with this allele
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Unc13btm2Bros mutation
(1 available);
any
Unc13b mutation
(119 available)
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vision/eye
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N |
• mice exhibit normal photoreceptor ribbon synaptic transmission
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• in peak-to-peak amplitudes and frequency of oscillatory potentials is slightly reduced compared to in wild-type mice
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• b-wave amplitude is very slightly reduced in photopic conditions
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• b-wave amplitude is slightly reduced in scotopic conditions
• however, b-wave implicit time is normal
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nervous system
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N |
• normal cytoarchitecture and ultrastructure of the CNS
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• observed in mice older than 12 months old
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• photoreceptor ribbon synapses contain slightly more docked synaptic vesicles than in wild-type mice
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behavior/neurological
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• observed in mice older than 12 months old
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mortality/aging
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• all mutants born alive, die within 1 hour after birth
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nervous system
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• length of active zones is larger in synapses, thus the number of docked vesicles per um active zone is lower, however mutants form normal numbers of synapses
• cultured neurons are unable to exocytose and lack calcium-triggered endocytotic activity
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• complete loss of fusion competent vesicles
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• flash-response is abolished in neurons compared with control mice
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• spontaneous, action potential evoked, and hypertonically evoked vesicular release (synaptic transmission) are abolished
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• excitatory postsynaptic current induced by calcium uncaging is abolished compared to in control mice
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Unc13atm2Bros mutation
(0 available);
any
Unc13a mutation
(74 available)
Unc13btm2Bros mutation
(1 available);
any
Unc13b mutation
(119 available)
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nervous system
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• spontaneous release rates are intermediate and are increased by PDBu (4beta-phorbol-12,13-dibutyrate) treatment
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• the number of fusion-competent vesicles is reduced to 2763+/-305 vesicles compared to 4109+/-722 vesicles in wild-type mice
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• at 10Hz action potential trains, excitatory postsynaptic current depression is enhanced relative to that in wild-type cells but not as much as in homozygotes and further enhanced by treatment with PDBu (4beta-phorbol-12,13-dibutyrate)
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Unc13atm2Bros mutation
(0 available);
any
Unc13a mutation
(74 available)
Unc13btm2Bros mutation
(1 available);
any
Unc13b mutation
(119 available)
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nervous system
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• the rate of vesicle release is doubled compared to in wild-type cells for all doses tested
• spontaneous release rates are increased and are not effected by PDBu (4beta-phorbol-12,13-dibutyrate) treatment
• the probability of vesicle release is increased relative to in wild-type cells
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• the number of fusion-competent vesicles is reduced to 2299+/-300 vesicles compared to 4109+/-722 vesicles in wild-type mice
• following stimulation with 250mM sucrose, the number of vesicles released is greater (2000+/-460 vesicles) than in wild-type cells (1100+/-300 vesicles)
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• at 10Hz action potential trains, excitatory postsynaptic current depression is enhanced relative to that in wild-type cells and is further enhanced by treatment with PDBu by (4beta-phorbol-12,13-dibutyrate)
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• the absolute frequency of miniature excitory postsynaptic currents is more than doubled that in wild-type cells but similar to that in phorbol ester-treated wild-type cells
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• long term potential is enhanced relative to in wild-type cells but similar to in that in wild-type cells treated with PDBu (4beta-phorbol-12,13-dibutyrate)
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Analysis Tools