Temporal lobe epilepsy (TLE) is a common seizure disorder, but the underlying molecular mechanisms are unknown. We reported previously that inactivation of the jerky gene in mice causes recurrent limbic seizures highly similar to TLE. Electrophysiological studies showed abnormal firing in hippocampal neurons in these mice, but it is not known how a deficiency in the Jerky protein leads to neuronal hyperexcitability. Here we show that Jerky is a brain-specific protein with a high expression level in neurons. Jerky binds mRNAs with high affinity, and it is a component of messenger ribonucleoprotein complexes in vivo. However, Jerky is not associated with ribosomes and actively translating mRNAs. These data suggest that Jerky may regulate mRNA use in neurons, and its deficiency could lead to perturbations in the regulated use of preexisting mRNAs.