Translation at the Synapse
The complex morphology of neurons, with synapses located hundreds of microns from the cell body, necessitates the localization of important cell biological machines, including ribosomes, within dendrites and axons. Local translation of mRNAs is important for the function and plasticity of synapses. Using advanced sequencing and imaging techniques we have updated our understanding of the local transcriptome and identified the local translatome- identifying over 800 transcripts for which local translation is the dominant source of protein. In addition, we have explored the unique mechanisms neurons use to meet protein demands at synapses, identifying surprising features of neuronal and synaptic protein synthesis.
Mechanisms to medicines in neurodegeneration
Dysregulation of protein synthesis both globally and locally in neurons and astrocytes is a key feature of neurodegenerative diseases. Aberrant signalling through the Unfolded Protein Response (UPR) and related Integrated Stress Response (ISR) have become major targets for neuroprotection in these disorders. In addition, other homeostatic mechanisms and stress responses, including the cold shock response, appear to regulate local translation and RNA splicing to control synapse maintenance and regeneration and can also be targeted therapeutically for neuroprotection. We have defined the role of UPR/ISR and the cold-shock response in neurodegenerative disorders and have developed translational strategies targeting them for new treatments for dementia.
Protein Synthesis at Neuronal Synapses
The complex morphology of neurons, with synapses located 100’s of microns from the cell body, necessitates the localization of important cell biological machines and processes within dendrites and axons. Using expansion microscopy together with metabolic labeling we have discovered that both postsynaptic spines and presynaptic terminals exhibit rapid translation, which exhibits differential sensitivity to different neurotransmitters and neuromodulators. In addition, we have explored the unique mechanisms neurons use to meet protein demands at synapses, identifying the transcriptome and translatome in the neuropil.