Research Fellows Directory
Dr Thomas Younts
University College London
I have investigated cellular and molecular mechanisms at synapses in the hippocampus, with a particular focus on long-term changes in synapse strength. Changes in the efficacy of synaptic transmission between neurons are thought to underlie certain forms of learning and memory. While much is known about the molecular events taking place in postsynaptic compartments during plasticity, much less is known about presynaptic mechanisms of synaptic plasticity. During my PhD, I discovered a new form of presynaptic long-term inhibitory plasticity mediated by the retrograde actions of endocannabinoids, providing a detailed account of how single neurons fine-tune their presynaptic inputs in a manner that depends solely on their postsynaptic activity. Using long-term paired recordings, I also provided direct evidence that this form of plasticity requires new protein synthesis in presynaptic compartments. This finding should help dispel a 50 year dogma that presynaptic translation does not occur in the mature mammalian brain. Finally, I identified, for the first time, a biological function for three presynaptic proteins, Synaptotagmin-12, AKAP7, and Rab3B. Each is essential for presynaptic long-term plasticity at certain hippocampal synapses, and AKAP7 and Rab3B were shown to be required for contextual learning and memory extinction, respectively. My research on presynaptic transmission and plasticity provides new insight into the mechanisms underlying learning and memory.
Interests and expertise (Subject groups)