Dynamic Signalling Cascade Activity Measurement in Live Single Cells
Event details
| Date | 08.02.2018 |
| Hour | 10:00 |
| Speaker | Eric Durandau, Ph.D., University of Lausanne - UNIL (CH) |
| Location | |
| Category | Conferences - Seminars |
BIOENGINEERING SEMINAR
Abstract:
All organisms are composed of a multitude of cell types, having each a specific task to accomplish. This cell-to-cell heterogeneity results from a complex interpretation of intra and extracellular cues by signalling cascades. Therefore, it becomes fundamental to investigate the signal processing by signalling cascades to understand how and why individual cell choose a particular fate. Perform such study requires to measure dynamically and simultaneously the activity state of multiple signalling cascade components in live single cells. To extract such information we used synthetic biology to design a synthetic protein probe, named SKARS, which relocates from the nucleus to the cytoplasm when being specifically phosphorylated by a Mitogen-Activated Protein Kinase (MAPK) of interest. We applied this technology in the study of the cross-interaction between the cell cycle and the mating pathway in the model organism Saccharomyces cerevisiae. We use the SKARS probe as a sensor of the mating MAPKs Fus3 and Kss1 and the transcription factor Whi5 as a sensor of the CDK Cdc28. By combining time-lapse fluorescent microscopy with computational analysis, we extracted the nucleus-to-cytoplasm shuttling of the two probes in hundreds of cells and used this as a proxy for MAPK and CDK activity. This strategy enables to extract information about the dynamic kinase activity with a higher quality compared to previously used methods. We observed that when cells are exposed to exogenous pheromone, the MAPK is differentially activated from one cell to another and that these different signal patterns are specifics of cell-cycle stages. Moreover, single cell analysis of mutant strains leads us to conclude that the model describing how the cell cycle regulates the mating pathway is incomplete. Our data supports the idea that the parallel measurement of multiple signalling cascades is a valuable strategy enlighten very subtle pathway cross-regulation events. Moreover, thanks to the straightforward structure of the SKARS, we strongly believe that this technique can be an advantage in fields such as development or cancer research.
Bio:
Université de Lausanne (CH)
Doctorate
2012 – 2017
Université Grenoble Alpes (F)
Master 2 (M2), Immunology microbiology Infectiology
2011 – 2012
Université Grenoble Alpes (F)
Master 1 (M1), Molecular Biology
2010 – 2011
Abstract:
All organisms are composed of a multitude of cell types, having each a specific task to accomplish. This cell-to-cell heterogeneity results from a complex interpretation of intra and extracellular cues by signalling cascades. Therefore, it becomes fundamental to investigate the signal processing by signalling cascades to understand how and why individual cell choose a particular fate. Perform such study requires to measure dynamically and simultaneously the activity state of multiple signalling cascade components in live single cells. To extract such information we used synthetic biology to design a synthetic protein probe, named SKARS, which relocates from the nucleus to the cytoplasm when being specifically phosphorylated by a Mitogen-Activated Protein Kinase (MAPK) of interest. We applied this technology in the study of the cross-interaction between the cell cycle and the mating pathway in the model organism Saccharomyces cerevisiae. We use the SKARS probe as a sensor of the mating MAPKs Fus3 and Kss1 and the transcription factor Whi5 as a sensor of the CDK Cdc28. By combining time-lapse fluorescent microscopy with computational analysis, we extracted the nucleus-to-cytoplasm shuttling of the two probes in hundreds of cells and used this as a proxy for MAPK and CDK activity. This strategy enables to extract information about the dynamic kinase activity with a higher quality compared to previously used methods. We observed that when cells are exposed to exogenous pheromone, the MAPK is differentially activated from one cell to another and that these different signal patterns are specifics of cell-cycle stages. Moreover, single cell analysis of mutant strains leads us to conclude that the model describing how the cell cycle regulates the mating pathway is incomplete. Our data supports the idea that the parallel measurement of multiple signalling cascades is a valuable strategy enlighten very subtle pathway cross-regulation events. Moreover, thanks to the straightforward structure of the SKARS, we strongly believe that this technique can be an advantage in fields such as development or cancer research.
Bio:
Université de Lausanne (CH)
Doctorate
2012 – 2017
Université Grenoble Alpes (F)
Master 2 (M2), Immunology microbiology Infectiology
2011 – 2012
Université Grenoble Alpes (F)
Master 1 (M1), Molecular Biology
2010 – 2011
Practical information
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