Dr Peter Watson - PhD
The compartmentalisation of mammalian cells allows the organisation of internal structures that have specific and distinct identity and function. Movement of components (proteins, lipids and solutes) between these structures is an ordered process, and occurs by the shuttling of membrane bound transport vesicles. Cargo is selectively incorporated into forming vesicles and targeted to their destination, where they fuse membranes with the acceptor compartment and deliver their cargo.
The machinery responsible for this targeted delivery needs to be returned to the original compartment to balance organelle homeostasis, and so these proteins are retrieved through a process of retrograde transport. Individual compartments are continually in a state of flux, and compartmental proteins and lipids are maintained through a balance of targeting, retention and retrieval. Components are continually moving between compartments, and it is the balance of traffic between them that defines the steady-state localisation of a molecule.
How mammalian cells regulate and spatially co-ordinate this process, to ensure that organelle homeostasis is maintained and cargo’s are delivered correctly, is the focus of my research. I am also interested in developing novel microscopy techniques to allow the visualisation and quantification of intracellular structures.
In collaboration with Dr Paola Borri and Professor Wolfgang Langbein, we are utilising coherent anti-stokes Raman scattering microscopy to study lipid homeostasis within eukaryotic cells. CARS microscopy joins the chemical sensitivity and label-free noninvasiveness offered by vibrational spectroscopy with the inherent 3D sectioning capability of multiphoton microscopy. We have recently published our work on a method to perform frequency differential CARS (D-CARS) in Optics Letters.
Four Wave mixing imaging (FWM)
In collaboration with Dr Paola Borri and Professor Wolfgang Langbein, we have demonstrated a novel multiphoton microscope based on the detection of four wave mixing emitted from gold nanoparticles. This allows us to perform background free imaging of single gold labels of small sizes (down to 5nm) with sub-micrometer resolution. We have recently published this work in Optics Letters and are now investigating the applicability of this technique to the life sciences.
We have a number of microscopes within the lab available for use.
Bernard: Widefield fast timelapse configured for DAPI/FITC/TRITC and CFP/YFP/RFP fluorescence imaging and phase contrast for brightfield imaging.
Clarissa: Widefield fast timelapse configured for DAPI/FITC/TRITC/Cy5 fluorescence imaging and DIC for brightfield imaging
Floyd: Zeiss LSM410 confocal system, currently being reconditioned. Still in use for TRITC/Cy5 fluorescence imaging.
We also have an eppendorf microinjection system that will fit on each of these microscopes to allow the microinjection, or microdelivery of material to the cell, or its local environment.
University of Bristol
University of Warwick