Corey Butler et al in Front. Bioinform.
A collaborative work between the teams of Jean-Baptiste Sibarita, Vincent Studer et Laurent Groc.
Single molecule localization (SML) and tracking (SPT) techniques, such as (spt)PALM, (u/ DNA)PAINT and quantum dot tracking, have given unprecedented insight into the nanoscale molecular organization and dynamics in living cells. They allow monitoring individual proteins with millisecond temporal resolution and high spatial resolution (<30 nm) by precisely localizing the point spread function (PSF) of individual emitters and tracking their position over time. While SPT methods have been extended to study the temporal dynamics and co-organization of multiple proteins, conventional experimental setups are restricted in the number of proteins they can probe simultaneously and usually have to tradeoff between the number of colors, the spatio-temporal resolution, and the field of view. Yet, localizing and tracking several proteins simultaneously at high spatial and temporal resolution within large field of views can provide important biological insights. By employing a dual-objective spectral imaging configuration compatible with live cell imaging combined with dedicated computation tools, we demonstrate simultaneous 3D single particle localization and tracking of multiple distinct species over large field of views to be feasible without compromising spatio-temporal resolution. The dispersive element introduced into the second optical path induces a spectrally dependent displacement, which we used to analytically separate up to five different fluorescent species of single emitters based on their emission spectra. We used commercially available microscope bodies aligned one on top of the other, offering biologists with a very ergonomic and flexible instrument covering a broad range of SMLM applications. Finally, we developed a powerful freely available software, called PALMTracer, which allows to quantitatively assess 3D + t + λ SMLM data. We illustrate the capacity of our approach by performing multi-color 3D DNA-PAINT of fixed samples, and demonstrate simultaneous tracking of multiple receptors in live fibroblast and neuron cultures.
Corey Butler made his PhD in collaboration between Jean-Baptiste Sibarita’s team and the company Imagine Optics. He then pursued his work in Jean-Baptiste Sibarita’s team as a post-doc before to be hired by the company Abbelight in 2021.
Multi-Dimensional Spectral Single Molecule Localization Microscopy
Corey Butler1,2, G Ezequiel Saraceno1, Adel Kechkar3, Nathan Bénac1, Vincent Studer1, Julien P. Dupuis1, Laurent Groc1, Rémi Galland1* and Jean-Baptiste Sibarita1*
1 Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297F-33000, F-33000, Bordeaux, France
2 Imagine Optic, Orsay, France
3 Ecole Nationale Supérieure de Biotechnologie, Laboratoire de Bioengineering, Constantine, El Khroub, Algeria