Impaired motor learning performance in cerebellar En-2 mutant mice.
Mice homozygous for a null mutation in their En-2 gene exhibit cerebellar neuroanatomical alterations including absence and misplacements of specific fissures and size reduction. The present study investigated cerebellar function by comparing the behavior of age-matched homozygous and heterozygous En-2 mutant and wild-type mice. Motor function of the mutants was found normal in several situations. Habituation to novelty in the open field was not significantly different in mutants. However, in a motor learning paradigm, the rotating rod, the performance of homozygous mutant mice improved significantly less than that of the heterozygous mice which were also significantly impaired compared to wild-type mice. Unlike other cerebellar mutants in which severe motor or sensory defects are obvious, the En-2 mouse model offers a unique tool to study the role of cerebellum in complex behavioral phenomena, including motor learning, without confounding effects.
Gerlai
R
R
Samuel Lunenfeld Research Institute, Neurobiology Division, Mount Sinai Hospital, Toronto, Ontario, Canada. gerlai@mshri.on.ca
Millen
K J
KJ
Herrup
K
K
Fabien
K
K
Joyner
A L
AL
Roder
J
J
D000818:Animals; D001143:Arousal / Q000235:genetics / Q000502:physiology; D002531:Cerebellum / Q000002:abnormalities* / Q000502:physiology; D005106:Exploratory Behavior / Q000502:physiology; D005801:Genes, Homeobox / Q000235:genetics*; D006579:Heterozygote; D018398:Homeodomain Proteins / Q000235:genetics*; D006720:Homozygote; D011939:Mental Recall / Q000502:physiology; D051379:Mice; D008818:Mice, Neurologic Mutants; D009048:Motor Skills / Q000502:physiology*; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics*; D004856:Postural Balance / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D000099266:Engrailed 2 Protein
D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D000099266:Engrailed 2 Protein