At the Bordeaux Imaging Center (BIC), we are looking for a motivated cell biologist to implement sample preparation, super-resolution imaging in cryogenic conditions and image treatment and analysis.

Cryo-electron microscopy provides not only access to the structure of isolated molecules at an atomic scale, but also to their structure in a cellular context. The need of a specific and highly precise localization of molecules previous to cryo-EM observation in a frozen hydrated sample has become evident. Super-resolution microscopy techniques based on single molecule localization could overcome the challenge of nanoscale detection in light microscopy. The EquipEx+ project NanoCryoCLEM coordinated by the University of Bordeaux aims to establish a cryo-CLEM workflow for super-resolution microscopy. In this context, the Bordeaux Imaging Center (BIC), the Institute interdisciplinaire de Neurosciences (IINS), and the Institute d’optique (LP2N), will collaborate to develop a new super-resolution optical system in cryogenic conditions. The ultimate goal of this project is the transfer of these frozen hydrated samples, analyzed by super-resolution microscopy, to the electronic microscope from the Institute Européen de Chimie et Biologie (IECB) for Cryo-tomography observation and structural analysis.

The main activities of the candidate will include:

  • To develop new protein labeling strategies with probes compatible for both optical super-resolution microscopy techniques, and protein localization in cryo-electron tomography. This work will be carried out in collaboration with research teams from IINS: «Spatio-Temporal and Mechanical Control of Motile Structures» led by Grégory Giannone, and «Dynamic Organization and Function of Synapses» led by Daniel Choquet.
  • To establish cell cultures on EM grids preserving specific subcellular structures and to plunge freeze the samples.
  • To acquire super-resolution images in cryogenic conditions with a home-made system.
  • To analyze and reconstruct super-resolved images.
  • To develop a correlative workflow in order to select and localize regions of interest in the optical system for cryo-electron tomography acquisition.

The candidate must hold a PhD and should have advanced expertise in cell biology and fluorescence microscopy techniques. In-depth knowledge of protein labeling biochemistry in cell cultures will be an advantage. Previous experience in cryo-fixation techniques and liquid nitrogen manipulation will also be an asset.

The candidate will be working in an interdisciplinary environment, thus strong teamworking skills and fluid English will be asked. The contract is 1 year research engineer renewable up to 3 years, salary depending on CV.

To apply please send a full CV and a cover letter to:

  • Mónica Fernández Monreal (monica.fernandez-monreal AT u-bordeaux.fr).

  • Gregory Giannone (gregory.giannone AT u-bordeaux.fr).

  • Daniel Choquet (daniel.choquet AT u-bordeaux.fr).

A PhD position is currently available at the Interdisciplinary Institute for Neuroscience (IINS) at Bordeaux to develop new super-resolution approaches for probing the fast and long-term dynamics of proteins in depth within complex tissues at high spatial resolution. This work will be based on a light-sheet microscope recently developed in the team and named soSPIM, which combines a single-objective with micro-fabricated chips featuring 45° mirrors1 . We already demonstrated the capabilities of this systems to perform multi-scale 3D imaging from the whole drosophila embryos scale down to the single cell scale. In addition, we have shown that the combination of the optical sectioning provided by the light sheet excitation with a high numerical objective enables to perform single molecule based super-resolution up to 30 µm deep above the coverslip. The aim of the project will be to improve the imaging capabilities of the soSPIM system to probe the various dynamics of adhesion proteins during the development of drosophila embryos at high spatial resolution. It will consist of implementing on the soSPIM system single particle tracking approaches and structured illumination microscopy methods2 to probe the fast and long-term dynamics of proteins respectively. To achieve this goal, we will implement both excitation beam shaping3 and adaptive optics4 in order to optimize the excitation and detection paths, respectively, and implement specific micro-fabrication processes to create devices dedicated to the imaging of drosophila embryos. In collaboration with G. Giannone team (IINS, Bordeaux) and N. Brown team (Gurdon Institute, Cambridge), we will then study the formation and maturation of adhesion sites during drosophila embryos development and their role in muscle tissue formation.