An E.Coli toxin can stimulate learning and memory

Diana et al show (at least for mice) that intracerebral injection of cytotoxic necrotizing factor 1 (CNF1) - a protein toxin from Escherichia coli that constitutively activates Rho GTPases and leads to remodeling of the cerebral actin cytoskeleton - enhances neurotransmission and synaptic plasticity, and improves learning and memory in various behavioral tasks. The effects persist for weeks and are not observed in mice treated with a recombinant CNF1 inactivated by a single amino acid replacement. The results suggest that learning ability can be improved through pharmacological manipulation of neural connectivity.