Brain cytoplasmic RNAs regulate translation initiation. The neuronal brain cytoplasmic RNA 1, gene (Bc1), is involved in synaptic plasticity. These mice carry a knockout allele for the Bc1 gene, in which the entire coding region has been replaced by a NEO cassette. On the mixed B6;129 background, homozygotes are more susceptible to audiogenic seizures due to neuronal hyperexcitability. Most homozygotes (84% on the B6;129 background) exposed to auditory stimulation (120dB alarm) exhibit generalized clonic-tonic convulsive seizures after 2 minutes of exposure, but recover after approximately 1 minute. Approximately a quarter of the mice die during the seizures. Homozygotes display reduced exploration behavior and increased anxiety. The Donating Investigator reports that on the C57BL/6 congenic background, homozygotes aged 18 - 21 days, exhibit excessive grooming behavior, and are not susceptible to audiogenic seizures.
Mice that are homozygous for the targeted mutation are viable and fertile. No transcript is detected by Northern blot analysis of brain, testes, and liver. During backcrossing, the Y chromosome may not have been fixed to the C57BL/6J genetic background.
When crossed to mice homozygous for the Fmr1tm1Cgr targeted mutation
(Stock No. 003024), the double mutant mice exhibit CA3 pyramidal
cell hyperexcitability that is more severe than observed in the single mutant lines.
