Phenotypes Associated with This Genotype

Genotype
MGI:3686896

• Allelic Composition: Kndc1^tm1Mnkm/Kndc1^tm1Mnkm
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6J

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

Increased branches and terminals of cerebellar granule cell dendrites in Kndc1^tm1Mnkm/Kndc1^tm1Mnkm cerebella

nervous system

abnormal cerebellar glomerulus morphology ( J:246827 )

• mice exhibit altered organization of mossy fiber-granule cell synapses within the cerebellar glomeruli

• at 5 weeks of age, expression analysis of presynaptic markers showed that the number of vGluT2-immunopositive puncta in excitatory mossy fibers is increased, whereas the number of GAD65/67-immunopositive puncta in inhibitory Golgi cell axons is normal relative to wild-type controls

• at 8 weeks of age, EM revealed an increased number of postsynaptic densities in cerebellar granule cells per mossy fiber terminal relative to wild-type controls

abnormal cerebellar granule cell morphology ( J:246827 )

• at 8 weeks of age, cerebellar granule cells show an increased number of dendrites per cell, branches per dendrite, and terminals per cell, but no difference in average dendrite length, relative to wild-type cells

• however, gross anatomy of the cerebellar lobules and layered cerebellar cortex, and cerebellar granule cell density appear normal

abnormal dendrite morphology ( J:246827 )

• at 8 weeks of age, mice show increased dendritic growth in cerebellar granule cells, leading to an increased number of dendrites, dendritic branches and terminals relative to wild-type mice

abnormal postsynaptic density morphology ( J:246827 )

• at 8 weeks of age, mice show an increased number of postsynaptic densities in cerebellar granule cells per mossy fiber terminal relative to wild-type controls

abnormal excitatory synapse morphology ( J:246827 )

• mice exhibit aberrant excitatory synaptic organization in the cerebellar glomeruli

behavior/neurological

behavior/neurological phenotype ( J:246827 )

N • mice show no alterations in various behavioral tests for memory, cognition, emotion and nociception relative to wild-type controls

enhanced coordination ( J:246827 )

• at 8 weeks of age, mice show slightly enhanced motor coordination in the balance beam test, with a shorter time to cross a narrow (6-mm) beam and fewer slips made than wild-type controls

• although rotarod performance is slightly enhanced at 8 weeks of age (only on the first trial on each day of training), no differences are noted after motor skill learning or at 30 weeks of age

• home cage activity, locomotion in an open field, and rearing activity are normal at 8-12 weeks of age

increased grip strength ( J:246827 )

• at 8-12 weeks of age, mice show increased grip strength relative to wild-type controls

• however, wire hanging ability is not significantly altered

mortality/aging

mortality/aging ( J:111319 )

N • homozygotes are fully viable and overtly normal

reproductive system

reproductive system phenotype ( J:111319 )

N • homozygotes exhibit normal reproductive capacity

growth/size/body

growth/size/body region phenotype ( J:246827 )

N • mice exhibit normal body shape and body weight relative to wild-type controls