Imaging Life 2018: Invited speakers and programme


Dr. Dylan Owen
King’s College London

Extracting biological information from super-resolution microscopy data
Super-resolution microscopy based on single molecule imaging does not produce images, but rather a spatial point pattern (SPP)- a list of the coordinates of the target molecules. By developing new analytical tools, we show how meaningful data can be extracted such a SPP. A straightforward implementation of this for example is “overview” cluster analysis via Ripley’s K-function, but we have also developed methods for the complete description of clustering via Bayesian and, recently, neural network machine learning-based methods. In a similar vein, we show that variants of the K-function can be used to give overview descriptions of SPPs generated from fibrous, rather than clustered structures, such as components of the cytoskeleton and that fibre tracing tools can be used to give complete descriptions of such fibrous SPPs. Our primary motivation in developing these tools is to understand the spatio-temporal arrangement of signalling machinery at the T cell immunological synapse.


Dr. Ignacio Casuso
Aix-Marseille Université

The HS-AFM and the cell membrane, news and views
The membranes of the cell enclose the different organelles and the cell themselves. All the signaling, nutritional and waste exchange between cells and organelles passes through or is generated in the membranes of cells, the membranes actively participate in the regulation of the metabolic biochemical pathways of the cells. Their medical relevance is highlighted by the fact that 70% of drugs work on the membranes of cells. The membrane biological function is regulated by a continuous dynamic and reversible reorganization of cell membranes structure including temporary association of protein or lipids and the formation of domains. Among the techniques to experimentally characterize the membrane architecture the High Speed Atomic Force Microscope (HS-AFM) is unique in providing imaging at sub-protein resolution of membrane structure in physiological conditions, and enabling the study of the dynamics of individual protein and membrane re-arrangements at subsecond timelapses.
(Right image: Representation of an AFM tip touching a cell membrane supported on mica immersed in physiological solution.)
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Dr. Vidya Darbari
Queen Mary University of London

Structural insights into bacterial transcription initiation by RNA polymerase - Variant Sigma factor σ54 holoenzyme complex.
Transcription in bacteria initiates with specific promoter recognition by sigma factors. The variant sigma factor σ54 is involved in transcription during various stress responses and does not share sequence or structural similarity to the housekeeping sigma factor σ70. The σ54-RNA polymerase holoenzyme complex is transcriptionally silent and requires activation by specialised ATP-dependent activators to initiate transcription. Structures of the holoenzyme complex, closed complex bound to a duplex DNA and intermediate complex bound to the activator protein and DNA have started revealing insights on how σ54 maintains the inhibitory state on the RNA polymerase until activation which is required to bring about necessary conformational changes for initiating mRNA synthesis. 
​We would like to thank the following companies for their sponsorship