Thesis defense Leos Cmarko

Equipe

Team II - Ion channels and cardiopathies

Directeur de thèse

Michel De Waard

Co-directeur

Norbert Weiss
 

Rapporteurs

Evelyne Benoit, PhD, CEA, Frédéric Joliot Institute for Life Sciences, Paris
Ladislav Vyklicky, DrSc., Fyziologický ústav AV ČR, v. v. i, Prague

Examinateurs

Isabelle Baro, PhD, l’institut du thorax, Nantes
Christine Berthier, PhD, Laboratoire Pathophysiologie et génétique du neurone et du muscle, Lyon
Karel Šonka, DrSc , Neurologická klinika 1. LF UK a VFN, Prague - president of the examination board
Pavla Jendelova, PhD, Ústav experimentální medicíny AV ČR, v. v. i., Prague

Abstract

T-type calcium channels (Cav3.1, Cav3.2, Cav3.3) play key roles in regulating neuronal excitability and numerous physiological functions. Dysregulation or mutations of these channels are linked to various neurological and neurodevelopmental disorders. Understanding the structure-function relationships and molecular mechanisms
is crucial for developing new therapeutic strategies. In this dissertation automated patch-clamp electrophysiology (APC) was used as a high-throughput screening platform to identify novel T-type channel modulators from a spider venom peptide library. The screening led to the discovery of a potent, subtype-specific peptide toxin
inhibitor, which was validated under recombinant and native conditions. Extending this pharmacological approach, manual patch-clamp electrophysiology (MPC) was used to test rationally designed small-molecule inhibitors of T-type channels. This effort yielded a lead compound with validated analgesic efficacy in preclinical
pain models. Finally, to highlight the complementarity of APC and MPC, eighteen Cav3.1 variants associated with neurodevelopmental disorders were characterized. APC was proven highly effective for high-throughput analysis of current density and channel gating properties, whereas MPC provides essential resolution for low-
expression variants. Altogether, this dissertation thesis provides new insights into T-type channel pharmacology and structure-function while highlighting the use of APC and MPC for drug discovery and classification of channel variants. Ultimately, these findings lay the groundwork for the development of novel T-type channel-targeted therapeutic strategies.