The mouse stargazer gene encodes a neuronal Ca2+-channel gamma subunit [see comments]
Amino Acid Sequence, Animal, Brain Chemistry, Calcium Channels, Cell Line, Cloning, Molecular, Epilepsy, Absence/genetics, Gene Expression Regulation, Genes, Structural, Hamsers, Mice, Mice, Neurologic Mutants, Molecular Sequence Data, Neurons/chemistry/physiology, Organ Specificity, Patch-Clamp Techniques, Restriction Mapping, RNA, Messanger/analysis, Sequence Analysis, DNA, Sequence Homology, Amino Acid, Synaptic Membranes/chemistry
Nat Genet 1998 Aug;19(4):340-7
Stargazer mice have spike-wave seizures characteristic of absence epilepsy, with accompanying defects in the cerebellum and inner ear. We describe here a novel gene, Cacng2, whose expression is disrupted in two stargazer alleles. It encodes a 36-kD protein (stargazin) with structural similarity to the gamma subunit of skeletal muscle voltage-gated calcium (Ca2+) channels. Stargazin is brain-specific and, like other neuronal Ca2+-channel subunits, is enriched in synaptic plasma membranes. In vitro, stargazin increases steady-state inactivation of alpha1 class A Ca2+ channels. The anticipated effect in stargazer mutants, inappropriate Ca2+ entry, may contribute to their more pronounced seizure phenotype compared with other mouse absence models with Ca2+-channel defects. The discovery that the stargazer gene encodes a gamma subunit completes the identification of the major subunit types for neuronal Ca2+ channels, namely alpha1, alpha2delta, beta and gamma, providing a new opportunity to understand how these channels function in the mammalian brain and how they may be targeted in the treatment of neuroexcitability disorders.
Letts, V A.; Felix, R; Biddlecome, G H.; Arikkath, J; Mahaffey, C L.; Valenzuela, A; Bartlett, F S.; Mori, Y; Campbell, K P.; and Frankel, W N., " The mouse stargazer gene encodes a neuronal Ca2+-channel gamma subunit [see comments]" (1998). Faculty Research 1990 - 1999. 1107.