A NOVEL SEIZURE-INDUCED SYNAPTOTAGMIN GENE IDENTIFIED BY DIFFERENTIALDISPLAY

Systemic administration of kainic acid, a cyclic analogue of glutamate , produces many of the clinical features of human temporal lobe epilep sy and status epilepticus in rats, including the induction of motor co nvulsions and the degeneration of neurons in the hippocampus and pirif orm cortex, Differential display PCR was used to identify mRNAs that a re differentially expressed between degenerating and nondegenerating t issues in the brain after kainic acid-induced seizure activity, A nove l cDNA fragment expressed in the degenerating hippocampus and piriform cortex, but not in the nondegenerating parietal cortex, was identifie d, cloned, and sequenced. This novel cDNA fragment identified a new me mber of the synaptotagmin gene family that is rapidly and transiently induced in response to seizure activity. Differential expression of th is synaptotagmin gene, syt X, was confirmed by Northern blot analysis and in situ hybridization. This novel, inducible synaptotagmin gene ma y provide a direct link between seizure-induced neuronal gene expressi on and subsequent modulation of synaptic structure and function.