3D scanning and uncaging two-photon microscopy

Seeing is believing. To understand the brain and nervous system, we need to know how mechanisms are mediated at the subcellular, cellular, and network levels. Regulation of neuronal communication at synapses is an example of a complex response at the subcellular level, with impacts on neuronal  network properties that in turn support functions from visual processing and pain regulation, to motor control, memory formation and emotion. Cellular signaling, homeostasis and change rely on proteins.  In neurons, we need to be able to observe protein dynamics (activity, localization, molecular interactions) within the tiny compartment of the synapse, as they occur in the context of neuronal activity and synaptic signaling.

NORBRAIN UiB will provide three complementary platforms for nanoscale optical interrogation of neuronal and synaptic function. The platforms will enable: 1) super-resolution-based localization and tracking of protein movement in cell culture preparations, 2) imaging of protein-protein interactions in intact tissue such as rodent brain slices, and 3) structural and functional imaging of single neurons and networks in intact neural tissue, in combination with neurotransmitter uncaging to study structural and functional plasticity and dendritic integration. 

3D scanning and two-photon uncaging microscopy

Two-photon (2P) microscopy is an extremely powerful technique that permits visualization and interrogation of complex neural tissue in 3D, with detailed subcellular resolution and minimal phototoxicity. When neurons receive and transform signals arising from hundreds and thousands of synaptic inputs, it is technically extremely challenging to investigate the underlying mechanisms at the necessary spatial and temporal resolution. When 2P microscopy is combined with 2P neurotransmitter uncaging, it becomes possible to precisely activate single and multiple synapses to investigate how dendrites transform synaptic inputs and how neurons and neural microcircuits process information. 

This instrument will allow 2P-based structural and functional imaging and neurotransmitter uncaging in live (in vitro) brain tissue slices, combined with multi-electrode patch-clamp recording.  

The University of Bergen (UiB) node is a cellular and molecular neuroscience unit with Clive Bramham and Espen Hartveit as local coordinators. 

The equipment is planned for installation and testing in 2021, and will become available to qualified users nationwide. A practical training course will be offered on a regular basis.