Interests
- Signal formation and integration in neural circuits with astroglia
- Organisational principles underlying synaptic structure and function
- Activity-dependent control of neurotransmitter release
- Nanomolar landscapes of basal Ca2+ in neurons and astroglia
This research contributes to the inter-disciplinary effort to address cellular mechanisms of epilepsy and other neurodegenerative diseases.
We combine two-photon excitation microscopy with patch-clamp electrophysiology and (opto)genetic tools to monitor calcium signalling in individual axonal boutons, dendritic spines and microscopic astroglial compartments in cultured cells, acute brain slices, and also in vivo.
A submillisecond-resolution solution-exchange methodology is used to probe receptor kinetics. We have developed compartmental and Monte Carlo biophysical models to examine (a) intracellular Ca2+ signalling, (b) rapid events inside and outside the synaptic cleft, (c) activity of neural networks involving astrocytes.
We have developed time-resolved fluorescence imaging methods to monitor nanomolar ion concentrations and quasi-instantaneous molecular diffusion in live cells in situ.
Collaborators
Stephane Oliet | INSERM Bordeaux | |
Valentin Nagerl | University of Bordeaux | |
Alexander Dityatev | DZNE, Magdeburg | |
Yuri Korchev | Imperial College London | |
Mike Stewart | Open University | |
Klaus Suhling | King’s College London | |
Alexander Gourine | UCL Physiology | |
Matt Jones | University of Bristol | |
Alexey Semyanov | Nizhny Novgorod Neuroscience Center, Russia | |
Sergej Kasparov | University of Bristol | |
Eckart Gundelfinger | Leibnitz Institute, Magdeburg | |
Gleb Sukhorukov, Andrei Sapelkin | Queen Mary's University of London | |
Ruth Ross | University of Toronto |
Funding support
- Wellcome Trust PRF
- NC3Rs
- MRC
- Wellcome Trust Collaborative Award
Facilities
We conduct experiments in organotypic slice cultures, acute brain slices, and in vivo, using five dedicated 2P excitation imaging systems (two Olympus FluoView1000 scopes, a twinned Femtonics Femto-2D, and a Femtonics Femto-Smart Dual), and a super-resolution Vutara 350 SR equipped for dSTORM imaging.
The FluoView systems (one shared with Professor Alex Gourine, designated for in vivo experiments) are equipped with dual scanheads for 2PE imaging and 2P uncaging, and FLIM detectors. The twinned Femtonics systems are for 2PE imaging and 2P uncaging using three fs lasers, also equipped with FLIM detectors and a fast 3D imaging capability. The Femto-Smart Dual system (designated for in vitro and in vivo) is equipped with a hybrid resonant / galvanic dual scanner, two fs lasers, optogenetic capabilities and replaceable FLIM detector.
Monte Carlo diffusion simulations and neuron network modelling are carried out using a dedicated 64-node client cluster adapted for parallel computing, but increasingly using cloud computing through a dedicated container-based environment (www.neuroalgebra.com). We use further experimental patch-clamp DIC rigs and facilities, including a fast-solution-exchange (1 ms resolution) drive rig equipped with an ultra-fast Evole 512 camera.