Cell and tissue imaging - UMR 3215 (pict-IBiSA)
Keywordsvideomicroscopy, confocal microscopy, cell ablation, developmental imaging, image processing and analysis
The imaging facility of the Unit of Developmental Biology and Genetics (UMR3215 CNRS / U934 INSERM) is a common service of optical microscopy and image analysis, located in the Developmental Biology and Cancer building on the Institut Curie's Paris campus. This service is part of the Platform for Cell and Tissue Imaging (PICT-IBiSA) of the Institute.
The missions of the imaging facility are as follows:
- to provide advanced technologies and expertise in optical microscopy and image analysis to the researchers of the Institut Curie unit and external researchers,
- to provide users with training, help and advice,
- to maintain a leading technological facility,
- to perform technical developments and to design technologies and software,
- to collaborate in scientific projects,
- to teach and to pass over knowledge.
The imaging service of the Unit of Developmental Biology and Genetics works in close collaboration with the unit's research teams, in order to provide them with tools dedicated to cell imaging of biological processes during the development of living organisms (see photo on Fig. 2).
Multiple difficulties have to be overcome to offer highly precise tracking of marked proteins over periods of time (for several hours or even several days), while maintaining spatial information (position of the protein in the cell, the tissue or the animal) and keeping the sample alive (see film).
Cell division in Drosophila epithelial tissue observed using confocal laser scanning microscopy over time. In green, one can track E-cadherin protein tagged with a Green Fluorescent Protein, which plays an important role in cellular adhesion
Recently developed fluorescent probes, in particular those developed by 2008 Chemistry Nobel laureates (Osamu Shimomura, Martin Chalfie et Roger Y. Tsien), are useful for long-term analysis, since they offer greater photostability over time and better luminosity. In addition, the use of microscope incubators enables to maintain organisms in physiological conditions through temperature control, CO2 percentage and humidity control. Finally, the development of more advanced microscopes enables in particular to collect the light emitted by these fluorescent probes, even when they are located deep in the sample, using powerful laser sources and highly-sensitive detectors.
Otherwise, resolution remains a limiting factor in optical microscopy, for precise observation of subcellular structures, such as nuclear proteins.The lateral resolution of a confocal microscope is approximately 250 nanometers (0.000000250 meters), which corresponds to the size of small bacteria (for ex. Mycoplasma), while the size of the structures we wish to observe is very often smaller (for ex. proteins, microtubules). A considerable breakthrough is now underway with the joint efforts of international physics, optics, chemistry and biology laboratories. The physical limitations in the field of optics are currently being overcome through the development of new technological approaches and intensive computational image processing. For example, structured-illumination microscopy enables to reveal interferences between the sample and the light source (Moiré effect). Another approach consists in using the physical characteristics of fluorescent probes to reduce the optical impulse response of the microscope in STED microscopy (“Stimulation Emission Depletion Microscopy”). Today these techniques are central to improving the resolution and thus the possibility of achieving a finer level of observation of living organisms.
A new equipment booking software will be implemented during first quarter 2016. The new software called Open IRIS will be presented to you very soon
Microscopy course organized by the CNRS at Institut Curie
Demo/test of Opterra microscope (Bruker) from 18/03/2015 to 1/04/2015. Please contact PICT@BDD imaging staff for more informations.
Light Microscopy Image Contest organized by the Labex DEEP and the PICT(BDD, Pav. Pasteur)
All publication should mention :"The authors would like to acknowledge the Cell and Tissue Imaging Platform of the Genetics and Developmental Biology Department (UMR3215/U934) of Institut Curie, member of France-Bioimaging (ANR-10-INSB-04), for help with light microscopy".