Translation regulation in normal and pathological conditions

Le lundi 24 avril 2023, Stéphane BELIN soutiendra son HDR intitulée "Translation regulation in normal and pathological conditions".

Composition du jury :

• Dr Sylvia SOARES, IBPS, Paris - Rapporteur
• Dr Emmanuel VALJENT, IGF, Montpellier - Rapporteur
• Dr Florence BESSE, IBV, Nice - Rapporteur
• Pr Alain BUISSON, Institut des Neurosciences, Grenoble - Examinateur
• Dr Emiliano RICCI, LBMC, ENS Lyon - Examinateur

Résumé :

A major challenge in Biology is to understand how genes are expressed and regulated in space and time in order to ensure cell specificity, homeostasis and organism development. Genetic expression is defined by the flow DNA-RNA-Protein. Tremendous amount of work focused on the first step when DNA is transcribed into RNA and provided detailed mechanisms of regulation during gene transcription in normal and pathological conditions. In contrast, the last step consisting of mRNA translation into proteins is still poorly addressed. However, recent work suggests that 1) cells rely on translation to control the expression of specific sets of mRNA during critical conditions and 2) translation is directly controlled by specific composition of the Translational Complex.
This is particularly important in the case of axon regeneration in the Central Nervous System (CNS) as neurons need to rely on specific genes expression to survive and regrow axons. Numerous studies aimed to unlock neuron survival and axon regeneration programs, mainly by analyzing mRNA content during CNS development and upon injury. These approaches revealed interesting targets but ultimately failed to expose all the programs necessary to stimulate sufficient axonal growth in order to build functional circuits after injury. In our group, we hypothesize that translation is a key step during development and injury in order to control the expression of specific sets of mRNA involved in axonal growth and/or survival. I will present our latest work demonstrating that the translational complex is a key hub controlling both central and peripheral nervous system by modulating its composition.