Scientific Speaker Series 2025 - BioImaging North America Site

Katiannah Moise – February 11

Katiannah Moise, Ph.D.
Northwestern University

Presentation Title: Proper Endothelial Cell Responses to Shear Stress Require Acetylation of Microtubules

Abstract:
Endothelial cells are constantly subjected to mechanical forces, especially shear stress, by virtue of their direct contact with blood flow. In order to adapt to these hemodynamic forces, endothelial cells remodel their cytoskeleton which includes changes in actin, intermediate filaments, and microtubules. In response to flow, endothelial cells exhibit two distinct responses: elongation in cell shape and realignment of cell body orientation parallel to the direction of flow. Deviation from these responses have been documented in many vascular diseases and a sign of endothelial dysfunctionWhile much is known about the effect of shear stress on the endothelial actin cytoskeleton, the impact of hemodynamic forces on the microtubule network has not been investigated in depth. Microtubules play a key role in maintaining cell shape and there are a host of proteins that regulate microtubule stability and filament length. In this talk, I will discuss how functional microtubule dynamics are vital for endothelial cells to properly respond to fluid shear stress. In addition, I discuss how post-translational modifications (PTMs) of microtubules, which regulate microtubule stability, play an important role in regulating when and how endothelial cells respond to shear stress. Using pharmacological and genetic methods to induce perturbations to microtubule properties, I show that alterations in microtubule dynamic instability block endothelial elongation and alignment. Moreover, altering the levels of microtubule acetylation– key PTM found to increase in expression as endothelial cells elongate in response to flow–results in similar impairment in cell shape and alignment. This talk explores the role of microtubule acetylation in endothelial mechanotransduction and uncovers essential roles for molecular regulators of acetylation in regulating endothelial function.