Date of Award
Winter 12-8-2025
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Molecular and Cellular Biochemistry Program
First Advisor
Patrick Oakes
Abstract
Cells interpret biochemical and mechanical signals through dynamic regulation of the cytoskeleton and adhesion complexes, enabling key processes such as shape adaptation, force generation and migration. As these signals vary in both time and space, they can be challenging to resolve using traditional bulk assays. To overcome this limitation, we employ light-based optogenetic tools to reversibly modulate biochemical signals and mechanical equilibrium within cells. Specifically, we use the iLID optogenetic approach to locally activate signaling and manipulate contractility within the cytoskeleton for the purpose of investigating the role of RhoA and contractility on septin organization and adhesion protein localization. We find that neither local accumulation of myosin nor enhanced myosin activity, both downstream effects of RhoA activation drive robust septin recruitment. This result was independent of the known RhoA and septin scaffolding protein anillin, therefore implying septins are downstream effectors of RhoA signaling. These results demonstrate that cytoskeletal responses arise from coordinated biochemical and mechanical cues and that these responses are highly protein specific, even within complexes and networks. Finally, this work establishes optogenetics as a powerful framework for dissecting spatiotemporal signaling and mechanotransduction in the cytoskeleton.
Recommended Citation
Chandrasekar, Shreya, "Using Light to Dissect Mechanisms of Septin Recruitment" (2025). Dissertations. 4293.
https://ecommons.luc.edu/luc_diss/4293
