Phenotypes Associated with This Genotype

Genotype
MGI:2446453

• Allelic Composition: Unc5c^{rcmTg(Ucp)1.23Kz}/Unc5c^{rcmTg(Ucp)1.23Kz}
• Genetic Background: involves: C57BL/6J * SJL/J

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

mortality/aging ( J:109043 )

N • Background Sensitivity: no difference from the expected number of homozygotes is detected at weaning unlike in mice crossed for 10 generations to C57BL/6J where no homozygotes survive to weaning

behavior/neurological

ataxia ( J:40243 )

nervous system

abnormal cerebellum development ( J:45577 , J:40243 )

• ectopic subpial cell populations identical to those in Unc5c^rcm homozygotes are seen (J:45577)

• an abnormal band of granule cells extends from the cerebellum into the inferior colliculus (J:40243)

• partial fusion of the inferior colliculus to the rostral cerebellum (J:40243)

abnormal cerebellar lobule formation ( J:40243 )

• only 5 lobes are formed

• vermal fissure formation is also abnormal in the lateral cerebral hemisphere

reduced cerebellar foliation ( J:40243 )

• a reduction in size and number of folia is seen in midline sagital sections

abnormal cerebellum external granule cell layer morphology ( J:40243 )

• abnormal external granule cell migration with cells migrating in cohorts rather than as single cells

• these abnormal groups of cells are often associated with gaps in the Purkinje cell layer

abnormal pyramidal decussation morphology ( J:80430 )

• the pyramidal decussation is thinner but present

abnormal inferior colliculus morphology ( J:40243 )

• an abnormal band of granule cells extends from the cerebellum into the inferior colliculus

• partial fusion of the inferior colliculus to the rostral cerebellum with ectopic granule and Purkinje cells in the inferior colliculus and tegmentum of the midbrain

abnormal cerebellar Purkinje cell layer ( J:40243 )

• abnormal groups of migrating granule cells are associated with gaps in the Purkinje cell layer

ectopic Purkinje cell ( J:45577 , J:40243 )

• in the inferior colliculus and pontine area at P7 (J:45577)

• in the inferior colliculus and tegmentum of the midbrain (J:40243)

ectopic cerebellar granule cells ( J:45577 , J:40243 )

• in the inferior colliculus and pontine area at P7 (J:45577)

• an abnormal band of granule cells extends from the cerebellum into the inferior colliculus (J:40243)

small cerebellum ( J:40243 )

• more pronounced than in Unc5c^rcm homozygotes

abnormal innervation pattern to muscle ( J:109043 )

• Background Sensitivity: penetrance and severity of the defect in diaphragm motor neuron innervation are decreased on a mixed mixed C57BL/6J and SJL/J background compared to an inbred C57BL/6J background

abnormal corticospinal tract morphology ( J:80430 )

• expression analysis indicates the absence of the corticospinal tract in the dorsal funiculus

• just before the decussation the pyramidal tract broadens and at the decussation 2 bundles of axons form with some but not all axons crossing the midline

• most axons that cross the midline fail to enter the dorsal funiculus and are instead found in the adjacent dorsal gray matter and just into the white matter of the contralateral lateral funiculus of the cervical and thoracic spinal cord

• axons that fail to cross the midline follow an ipsilateral path into the lateral funiculus

abnormal trochlear nerve morphology ( J:109043 )

• Background Sensitivity: only 2 of 5mice have abnormalities in at least 1 trochlear nerve on a mixed C57BL/6J and SJL/J background while abnormalities are seen in all mice on an inbred C57BL/6J background

abnormal spinal cord dorsal column morphology ( J:80430 )

• the dorsal funiculus is smaller and its ventral aspect appears shorter and thinner

• expression analysis indicates the absence of the corticospinal tract in the dorsal funiculus