In collaborative work between the Li and Distefano research groups published recently in Molecular Neurobiology, graduate students Wendy Qu and Kiall Suazo discovered that conditional mouse knockout of farnesyl transferase (FT) leads to reduced synaptic plasticity, memory retention, and hippocampal dendritic spine density. Prenylomic analysis using in vitro prenylation with a synthetic isoprenoid analogue allowed specific proteins impacted to be identified. These results demonstrate that physiological levels of FT (and GGT) in neurons are essential for normal synaptic/cognitive functions and that the prenylation status of specific signaling molecules regulates neuronal functions. These results have important implications for improving understanding of brain-related diseases including Alzheimer's disease.