Missions

We are looking for a strong and motivated candidate to fill a postdoctoral position in the "Integrative Biophysics of Membranes" group at the CBS in Montpellier, France. Our project investigates the regulation of the metalloprotease ADAM10 trafficking by tetraspanins in colon cancer, using single-molecule techniques.

Activités

- Single-molecule biophysics (single-molecule localization microscopies and single-molecule Förster Resonance Energy Transfer)
- Genetic code expansion strategy to specifically label proteins
- Image analysis
- Programming
- Wet lab activities (biochemistry, cell and molecular biology)

Compétences

We are seeking a candidate with a PhD who:
- has a strong background in biophysics, optics, quantitative biology and related discipline;
- has experience with various microscopy techniques, particularly single molecule localization microscopies (STORM, PAINT and SMT);
- has experience of FRET (not mandatory)
- has experience in labelling of proteins and/or DNA;
- has advanced skills in image analysis based on single molecule detection;
- has experience with programming (our group mainly works in Python);
- has experience in cell culture and cell biology;
- enjoys working in an interdisciplinary environment;
- is highly motivated and able to work independently;
- should have a solid publication record (at least one paper as first author).
High-level communication skills are an asset.

Contexte de travail

Our group at the Center for Structural Biology (CBS) at the University of Montpellier (in the south of France) has one postdoctoral position available for 24 months. The successful candidate will work on the regulation of the trafficking of the metalloprotease ADAM10 by tetraspanins in colon cancer, using single-molecule techniques. Our international team is based at an interdisciplinary research center with excellent in-house access to state-of-the-art biophysics and structural infrastructure as well as biochemistry and cell culture facilities. Our multidisciplinary team counts 16 people including 6 permanent researchers.

Building on our expertise in using single molecule techniques to study tetraspanins (see references below), the project aims to understand how some proteins in the TSPANC8 family regulate the cleavage of substrates by the protease ADAM10, a key protein in tumour progression and proposed as a potential therapeutic target in cancer treatment. We will use single-molecule Förster resonance energy transfer (smFRET) to measure distances (resolution greater than 0.5 nm, range 2-10 nm) between individual interacting molecules. As this technique necessitates the conjugation of a donor and an acceptor fluorophore in precise positions on the two proteins, we will employ a genetic code expansion strategy, developed in the group, to incorporate small reactive non-canonical amino acids. This allows us to attach fluorescent probes at the desired positions using bioorthogonal chemistries, which minimizes the impact on the protein structure and makes distance measurements more accurate.

We will also carry out molecular mapping of ADAM10 and its substrates using DNA PAINT experiments to analyze the distances between these proteins on a nanometer scale in intact cells. This should reflect the probability of the enzyme to cleave a given protein in the presence or absence of TSPANC8 proteins. ADAM10 dynamics, as measured by SMT, will help to understand this molecular landscape.
This project is funded by an INCA French grant.

References
- Fernandez et al (2021) CD82 and gangliosides tune CD81 membrane behavior, Int J Mol Sci. 2021 Aug 6;22(16):8459. doi: 10.3390/ijms22168459.
- Dahmane et al (2019) Nanoscale Organization of Tetraspanins during HIV-1 budding by correlative dSTORM/AFM. Nanoscale 1(13):6036-6044. doi: 10.1039/c8nr07269h.
- Jouannet et al (2015) TspanC8 tetraspanins differentially regulate the cleavage of ADAM10 substrates, Notch activation and ADAM10 membrane compartmentalization. CMLS 73(9):1895-915. doi: 10.1007/s00018-015-2111-z.

Contraintes et risques

Initial contract duration: 1 year, renewable once.
Interested applicants should submit their CV, cover letter and references.