Regulated expression of the neuronal calcium sensor-1 gene during long-term potentiation in the dentate gyrus in vivo

Neuronal calcium sensor-1 (NCS-1), the mammalian homologue of frequenin. is a member of a highly conserved family of neuron-specific calcium-binding p roteins which has been implicated in exocytosis and in multiple calcium-sig nalling pathways, suggesting a potential involvement in mechanisms of neuro nal plasticity. Here, using in situ hybridization. we report an increased i nduction of the mRNA encoding NCS-1 in dentate granule cells following the induction of long-term potentiation in the awake rat, We show that NCS-1 mR NA levels are increased 1 and 3 h after long-term potentiation in an N-meth yl-D-aspartate receptor-dependent manner, returning to baseline expression levels by 6 h. Electroconvulsive stimulation also induced NCS-1 mRNA transc ription in the dentate gyrus, but at the different time of 6 h post-seizure , returning to baseline by 12 h. These results show that regulated expression of the NCS-1 gene is part of t he transcriptional response associated with activity-dependent neuronal pla sticity in vivo and suggest a molecular mechanism capable of mediating a fu nctional change in synapse sensitivity to calcium and calcium-signalling pa thways after long-term potentiation. (C) 2001 IBRO. Published by Elsevier S cience Ltd. All rights reserved.