Description du sujet de thèse

Rett syndrome (RTT) is a rare X-linked neurodevelopmental disorder (1/10,000 female births), caused in more than 95% of cases by mutations in the MECP2 gene. After initial normal development, patients regress between 6 and 18 months, losing their motor and communication skills. Although re-expression of MeCP2 in mice can reverse symptoms, current gene therapy approaches present a risk related to toxicity linked to overexpression of the transgene. In this context, synthetic biology offers new alternatives thanks to gene circuits/cascades capable, for example, of finely adjusting gene expression. The thesis project is part of a collaboration between SPPIN and ENS in Paris and aims to develop a “minimal” and modular gene cascade to control MeCP2 re-expression and avoid any dosage drift. The thesis work will consist of designing and testing vectors containing gene cascades first during a first screening in HEK cells and then in mouse neuron cultures to evaluate their ability to restore neuronal morphology. After this in vitro validation, the cascade will be integrated into AAV viral vectors for efficient neuronal transduction in vivo. We will thus measure MeCP2 levels, the complexity of dendritic arborization and spine density, then the improvement of the behavior of mice treated with these AAVs using imaging and behavior platforms at SPPIN. This project will allow the control of MeCP2 expression in order to optimize the efficacy of RTT gene therapy, while establishing a modular framework for future self-regulated therapeutic approaches.

Contexte de travail

SPPIN is a neuroscience research institute of the CNRS and Université Paris Cité located on the Saints-Germain-des-Prés campus whose objective is to characterize the mechanisms underlying brain functions, from synaptic transmission to the activity of neuronal networks and how this translates into specific behaviors in healthy and pathological conditions. To achieve these objectives, SPPIN adopts a multidisciplinary approach combining optical microscopy, electrophysiology, biochemistry, molecular biology, and behavior analysis and conducts studies at different scales.

Contraintes et risques

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Informations complémentaires

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