Keywords: 2 photon uncaging, NMDA receptors, co-agonists, Optochemistry Internship Duration: 30/11/-1 - 30/11/-1
Head of the hosting team: Jean-Pierre Mothet
Address of the host laboratory: LuMIN UMR9024 Team Biophotonics and Synapse Physiopathology (BioPSy) ENS Paris Saclay, 4 avenue des Sciences 91190 Gif-sur-Yvette France
Supervisor: Jean-Pierre MothetE-mail: jean-pierre.mothet@universite-paris-saclay.fr Phone: +33(0) 18187 5641
Scientific context of the project The host team has discovered that NMDA receptors, which are vital for healthy brain functions, are regulated by D-serine and glycine (1). Despite significant progress, our understanding of the role played by each of these amino acids in controlling brain activity is still poor because we lack the appropriate tools. In collaboration with Mireille Blanchard-Desce's team (CNRS - University of Bordeaux), we have undertaken to unlock these obstacles by developing new probes based on optochemistry (2). The idea is to be able to optically control native receptors and to allow non-invasive interrogation of the functioning of brain circuits with unequalled precision (< 1 µm). We have developed new compounds that cage D-serine and glycine for use in 1 and 2 photon microscopy. In this context, we selected two types of cages according to two criteria: high photolysis efficiency at 2P (> 0.1 GM) and orthogonal photolysis for D-serine and glycine. The cages (patterns capable of photolysis release of neurotransmitters only at a given irradiation) must allow photorelease at different wavelengths of the two distinct amino acids. Main objectives of the internship The main task of the student will be to characterise the now synthesised caged probes. First, the student will have to extract the photolysis properties of these cages during experiments measuring the efficiency of the release of the amino acids D-serine and glycine under 1- and 2-photon light irradiation at different wavelengths using a new capillary electrophoresis system coupled to a multi-wavelength fluorescent detection that we have just acquired. In a second phase, the student will have to valorise these probes by implementing photo uncaging experiments using our multiphoton microscopy on biological preparations (primary cultures of neurons) to study the effect of D-serine and glycine photorelease on the activity of NMDA receptors and neuronal activity. Positionning of the research project From a scientific point of view, this project will allow major advances in our understanding of the role played by D-serine and glycine in brain physiopathology. From a technological point of view, this project will allow the introduction of innovative and unique optical tools which, beyond the field of neuroscience, will offer applications in other disciplines in biology as well.
Multimodal laser induced fluorescent capillary electrophoresis Measurements of 2photon photolysis efficiency Orthogonal 2 photon uncaging on primary cultured neurons
(1) Le Bail M, et al. (2015). Proc Natl Acad Sci USA. 12(2):E204-13 (2) Carrillo-Reid L, et al. (2017). Annual Review of Biophysics 46:271–293.
