BBSRC White Rose DTP Studentship - Form and function: adapting dendritic morphology and synaptic location to optimise neural activity

How do neurons know what shape they should be and where to put their synapses? Are these morphological features tuned to allow neurons to exhibit ‘optimal’ patterns of neural activity? What does ‘optimal’ or ‘tuned’ even mean? We will address these questions in the memory centre of the fruit fly Drosophila. Our computational models predict that to maximise memory capacity, the memory-encoding neurons, called Kenyon cells, should compensate for natural variability in intrinsic excitability to equalise their average firing rate across the population. One way they could do this is by adjusting morphology: an over-active Kenyon cell could make its dendrites longer/thinner, or place input synapses far from the spike initiation zone, so that input signals would decay before they arrive at the neuron’s signal integration zone.

We will test this hypothesis using three complementary techniques: by analysing the detailed morphology of Kenyon cells in complete electron-microscopic reconstructions of the fly brain, called ‘connectomes’; by testing if changing the excitability of single Kenyon cells alters their morphology or other physiological properties; and by modelling whether observed morphological changes can effectively compensate for natural variability. This interdisciplinary project will train you in both experimental and computational neuroscience.

Key words: Learning and memory, imaging, neuronal morphology, synaptic plasticity, Drosophila, computational modelling, Applied