Guest Speaker Dr. Maria Kilfoil - Physics Department Seminar Series - FR

Event date(s): October 19, 2023
Time(s): 01:15 PM - 02:15 PM
Category: Fredericton
Location: Fredericton

Dr. Maria Kilfoil, an experimental physicist, uses optical and fluorescence microscopy tools to identify mechanical properties in biological and active materials such as cell cytoskeleton and DNA networks. She probes for characteristics of active (as opposed to thermally driven) microscopic motion and works to understand better how to the activity of enzymes and other machinery from the cell produce enhanced mechanical response.

Thursday, Oct. 19, from 1:15 p.m. to 2:15 p.m.
Toole Hall Room 3

Title: How it feels in a cell nucleus

Abstract: In the crowded physical environment of the cell nucleus, dominated by the DNA, motion of all the important molecules is a challenge. There is a thriving field in biophysical physics studying cellular mechanics, but the underlying non-equilibrium physics is far from understood. In this talk, I will discuss the non-equilibrium effects of a topology-relaxing enzyme on lambda-DNA at concentrations that are biophysically relevant.  I will present microscopic measurements of the mechanical properties of living cell nuclei and on a model system of DNA at physiologically relevant concentrations with enzyme activity of topoisomerase II.  The results show that the enzyme-driven fluctuations are quantitatively consistent with 1/f noise, far from what is expected for thermal motion, and of a completely different frequency dependence from non-equilibrium fluctuations in the cytoplasm driven by processive cytoskeleton motors. I will present this work in the context of a broader goal to make active matter systems without ignoring the cellular microenvironment, and to consider self-repair in these systems in response to the micro-environment.
 

Building: Toole Hall

Room Number: 3