Applied Math Seminar | Anmar Khadra, Characterizing anatomical and electrical properties of axonal fibers in gene edited mice using computational approaches

MC 6460

Speaker

Anmar Khadra, Department of Physiology, McGill University, Canada

Title

Characterizing anatomical and electrical properties of axonal fibers in gene edited mice using computational approaches

Abstract

Myelin sheaths are composed of spirally wrapped oligodendrocyte plasma membrane tightly compacted by a family of myelin-associated proteins that protect and insolate axonal fibers in neurons. They increase the transverse resistance of each fibre and lead to voltage-gated Na channel clustering at nodes of Ranvier supporting node-to-node saltatory conduction, which vastly accelerates conduction rates and limits repolarization energy requirements to the nodal domain. Adult myelin is adaptive with a rapidly growing evidence suggesting that such plasticity plays a key role in both normal and abnormal nervous system function. Insight into the mechanism through which such myelin changes are mediated remains limited. We have recently used computational techniques, image analysis and modeling approaches to quantify the relation between the different parameters defining the anatomy of axonal fibers in gene-edited mice and to explore how they affect their functional properties. Using cable theory, we then investigated how these anatomical parameters defining axonal fibers and their electrical properties affect signal propagation along these myelinated axons. In this talk, I will provide an overview of the results obtained focusing on two key aspects: myelin-sheath plasticity in vivo and signal conduction along myelinated axonal fibers.