Le mardi 27 janvier 2026, Madame Nathalie SCHUMACHER, titulaire d'un Master en Sciences biomédicales à finalité approfondie et d’un Certificat de formation à la recherche en sciences biomédicales et pharmaceutiques, présentera l'examen en vue de l'obtention du grade de Doctorat en sciences biomédicales et pharmaceutiques, sous la direction de Madame Rachelle FRANZEN et de Monsieur Renaud VANDENBOSCH.

Cette épreuve consistera en la défense publique d'une thèse intitulée : "Disentangling the role of Cdk7 in Schwann cell differentiation and peripheral nervous system myelination". 

Le jury sera composé de :

Olivier PEULEN (Président), Virginie NEIRINCKX (Secrétaire), Jeroen BOGIE (UHasselt), Laurence DELACROIX, Rachelle FRANZEN, Claire JACOB (Univ. Mainz), Isabelle LIEVENS, Renaud VANDENBOSCH.

Résumé de la thèse

Schwann cells (SC) are glial cells responsible for myelination in the peripheral nervous system, a fundamental process allowing rapid saltatory transmission of action potentials along axons. In fact, the unique lipid and protein constitution of myelin confers not only insulating property, but also guarantees axo-glial homeostasis. Disturbed lipid metabolism and myelin protein function or expression in SCs thus often represent prominent hallmarks of dysfunctional myelination. SC differentiation constitutes a stepwise process involving an accurate coordination of proliferation and fine-tuned gene expression. This manuscript sheds light on the role of Cyclin-dependent kinase 7 (Cdk7) in SC biology, commonly referred as regulator of cell cycle progression and transcription. Taking advantage of  transgenic mice with conditional Cdk7 knock-out in SCs (Cdk7-cKO), we provide evidence that Cdk7 is mostly dispensable for perinatal SC proliferation but needed for proper myelination and optimal nerve conduction velocity. Indeed, Cdk7 contributes to the expression of myelin protein zero and of lipid-related genes, and is needed for balanced myelin protein and lipid constitution in sciatic nerves. In this context, the nuclear receptor RXRγ emerged as a transcriptional Cdk7 target-candidate for dysregulated expression of fatty-acid related genes during SC differentiation.