Gene Expression in Hippocampal Long-Term Potentiation

Abstract
Recent work on hippocampal LTP has focused on gene expression induced with high frequency stimulation, as well as the signal transduction cascades responsible for the induction of these genes. Many scenarios for LTP lasting for greater than 5 hours include some or all of the following processes: 1) tagging of potentiated synapses, possibly by phosphorylation; 2) signaling to the nucleus; 3) kinase cascades and transcription factors in the nucleus;, 4) expression of immediate-early genes and/or synaptic proteins; and, finally, 5) targeting of newly synthesized proteins (or RNAs) to the potentiated synapses (and not to the unpotentiated synapses). Unfortunately, most scenarios proposed for the late-phase expression of LTP are still highly speculative at this time. A critical review of the literature relating to the role of gene expression in hippocampal LTP and a discussion of recent work on the subject will be presented. NEUROSCIENTIST 5:275-279, 1999