Phenotypes associated with this allele
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Kif21atm1.1Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
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vision/eye
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• mice exhibit unilateral or bilateral ptosis and/or globe retraction that is 92% penetrant and primarily bilateral
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• the levator palpebrae superioris muscle is reduced in size, with persistent attachment to the superior rectus
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• mice exhibit unilateral or bilateral ptosis and/or globe retraction that is 92% penetrant and primarily bilateral
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nervous system
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• levator palpebrae superioris and superior rectus extraocular muscle innervation, and to a lesser degree, lateral rectus extraocular muscle innervation, are altered
• however, innervation of other extraocular muscles, ciliary ganglion, nasal sensory pad, and efferent fibers to the cochlea are not affected
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• bilaterally affected mice have a 38% and 12% reduction in the number of distal oculomotor nerve and abducens motor neurons, respectively
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• bilaterally affected mice have a 12% reduction in the number of distal abducens motor neurons
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• bilaterally affected mice have a 38% reduction in the number of distal oculomotor nerve motor neurons
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muscle
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• the levator palpebrae superioris muscle is reduced in size, with persistent attachment to the superior rectus
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Allelic
Composition |
Kif21atm1.1Ece/Kif21a+
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Genetic
Background |
involves: 129S1/Sv * 129S4/SvJae |
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Kif21atm1.1Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
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vision/eye
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• mice exhibit unilateral or bilateral ptosis and/or globe retraction that is 43% penetrant and primarily unilateral
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• mice exhibit unilateral or bilateral ptosis and/or globe retraction that is 43% penetrant and primarily unilateral
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nervous system
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• about 50% of distal oculomotor nerves have only mild proximal thickening and distal thinning compared to wild-type, the other 50% have proximal bulbs and significant distal nerve hypoplasia and branching defects
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Kif21atm1.1Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
Kif21atm3Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
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vision/eye
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• 22% of mice show an external congenital fibrosis of the extraocular muscles phenotype that is mild
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muscle
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• 22% of mice show an external congenital fibrosis of the extraocular muscles phenotype that is mild
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Kif21atm1.1Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
Map1btm1Prop mutation
(0 available);
any
Map1b mutation
(85 available)
Tg(Isl1-EGFP*)1Slp mutation
(1 available)
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nervous system
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• approximately 90% penetrance of abducens nerve hypoplasia
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• oculomotor nerve superior branch axons terminate prematurely within a bulb with a penetrance of 90%
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Kif21atm1.1Ece mutation
(0 available);
any
Kif21a mutation
(81 available)
Tg(Isl1-EGFP*)1Slp mutation
(1 available)
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vision/eye
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• extraocular muscle hypoplasia begins after P0, several days after extraocular muscle innervation is reduced, with normal position and size of the superior rectus and superior rectus muscles at E14.5
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nervous system
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• oculomotor nerve neurons show increased apoptosis from E12.5-E15.5
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• oculomotor nerve neurons show failure of axon elongation to the orbit; this nerve growth failure precedes motor neuron apoptosis
• developing axons of the oculomotor nerves superior division stall in the proximal nerve, and the growth cones enlarge, extend excessive filopodia, and assume random trajectories while inferior division axons reach the orbit but branch ectopically
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• oculomotor explant axons have normal growth but enlarged growth cones and increased filopodia
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• the distal abducens nerves appear thin at E12.5 and are thinner at E15.5
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• oculomotor nerve superior branch axons terminate prematurely within a bulb; the bulb contains misdirected axons with enlarged growth cones and increased number of filopodia and degenerating axons
• the developing distal oculomotor nerve superior division is hypoplastic while the inferior division develops aberrant branches
• the oculomotor nerve distal sections contain 55% fewer axons than proximal sections, and the proximal sections contain 18% fewer axons than wild-type proximal sections
• oculomotor nerve pathology does not arise from a primary defect in extraocular muscle development, axon retraction, or motor neuron cell death
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• thinning of distal oculomotor nerves at E11.5
• the developing oculomotor nerves superior division is thinner than that of wild-type mice, while the oculomotor nerves inferior division appears moderately thinner, with premature fasciculation into transient aberrant branches
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muscle
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• extraocular muscle hypoplasia begins after P0, several days after extraocular muscle innervation is reduced, with normal position and size of the superior rectus and superior rectus muscles at E14.5
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cellular
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• oculomotor nerve neurons show increased apoptosis from E12.5-E15.5
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• oculomotor nerve neurons show failure of axon elongation to the orbit; this nerve growth failure precedes motor neuron apoptosis
• developing axons of the oculomotor nerves superior division stall in the proximal nerve, and the growth cones enlarge, extend excessive filopodia, and assume random trajectories while inferior division axons reach the orbit but branch ectopically
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Analysis Tools