GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.
PMID:9614225
| Citation |
Lorenzon, NM, Lutz, CM, Frankel, WN and Beam, KG (1998) Altered calcium channel currents in Purkinje cells of the neurological mutant mouse leaner. J. Neurosci. 18:4482-9 |
|---|---|
| Abstract |
Mutations of the alpha1A calcium channel subunit have been shown to cause such human neurological diseases as familial hemiplegic migraine, episodic ataxia-2, and spinocerebellar ataxia 6 and also to cause the murine neurological phenotypes of tottering and leaner. The leaner phenotype is recessive and characterized by ataxia with cortical spike and wave discharges (similar to absence epilepsy in humans) and a gradual degeneration of cerebellar Purkinje and granule cells. The mutation responsible is a single-base substitution that produces truncation of the normal open reading frame beyond repeat IV and expression of a novel C-terminal sequence. Here, we have used whole-cell recordings to determine whether the leaner mutation alters calcium channel currents in cerebellar Purkinje cells, both because these cells are profoundly affected in leaner mice and because they normally express high levels of alpha1A. In Purkinje cells from normal mice, 82% of the whole-cell current was blocked by 100 nM omega-agatoxin-IVA. In Purkinje cells from homozygous leaner mice, this omega-agatoxin-IVA-sensitive current was 65% smaller than in control cells. Although attenuated, the omega-agatoxin-IVA-sensitive current in homozygous leaner cells had properties indistinguishable from that of normal Purkinje neurons. Additionally, the omega-agatoxin-IVA-insensitive current was unaffected in homozygous leaner mice. Thus, the leaner mutation selectively reduces P-type currents in Purkinje cells, and the alpha1A subunit and P-type current appear to be essential for normal cerebellar function. |
| Links | |
| Keywords |
Animals; Barium/physiology; Calcium Channel Blockers/pharmacology; Calcium Channels/drug effects; Calcium Channels/physiology; Electric Conductivity; Mice; Mice, Neurologic Mutants/metabolism; Purkinje Cells/metabolism; Purkinje Cells/physiology; Spider Venoms/pharmacology; omega-Agatoxin IVA |
| edit table |
Significance
Annotations
| Gene product | Qualifier | GO ID | GO term name | Evidence Code | with/from | Aspect | Notes | Status |
|---|---|---|---|---|---|---|---|---|
| edit table |
See also
References
See Help:References for how to manage references in GONUTS.
