Evolutionary Origin of Synapses and Neurons
Neurons, synapses, and the proteins required for their function are critical to the biology and behaviour of animals, but little is known about how they first evolved. In neurons, the transmission of chemical signals (called neuropeptides or neurotransmitters) from the presynapse to the postsynapse requires distinct sets of pre- and postsynaptic protein networks. Understanding when the proteins required for synaptic activity first evolved and how they functioned in the first animals promises to illuminate evolutionary processes underlying the origin of neurons. We are particularly interested in:
- The origin and functional evolution of synaptic proteins
- Co-option of these proteins into ancient synaptic scaffolds
- Evolution of the first neuron-like cell type in animals
The goal of our laboratory is to reconstruct the origin and evolution of synaptic proteins. We use a comparative approach and work with choanoflagellates, the closest living relatives of animals, sponges, basal animals with no synapses and neurons, and ctenophores, basal animals with synapses and neurons, as model organisms. We aim to understand when the proteins required for synaptic activity first evolved, how they functioned at a molecular level and which combinations of synaptic proteins resulted in the origin of the synapse. Our approach is to use a variety of techniques, ranging from comparative genomics, immunofluorescence and electron microscopy, current state-of-the-art biochemical methods to X-ray crystallography to study synaptic protein homologs in choanoflagellates, sponges and ctenophores. Through our work we will be able to reconstruct the evolutionary history of these proteins and understand the evolution of the first synapses and neurons.