Tunable collective dynamics of inclusions in viscous biological membranes

Harishankar Manikantan

Assistant Professor,
UC Davis

Seminar Information

Seminar Series
Biomechanics & Medical Devices

Seminar Date - Time
October 1, 2021, 9:00 am
-
10:00


Abstract

The typical cell membrane is a crowded assembly of molecular motors and biomolecules embedded in a 2D fluid mosaic. Active molecular motors perform complex cellular tasks by binding, inserting, polymerizing, and changing conformations, inducing disturbance flows in the membrane and the surrounding fluid. These long-ranged hydrodynamic fields perturb neighboring inclusions, potentially leading to coordinated motion. I will build on classic theories of Newtonian fluid dynamics of viscous membranes to illustrate unique oscillations and aggregation dynamics in pairs of active membrane inclusions. The phase behavior of the pair problem reveals the underlying mechanisms and suggests strategies to tune large-scale aggregation. I will also show numerical simulations of large numbers of interacting inclusions whose collective dynamics can be tuned based on these basic insights. If time permits, I will then describe the first steps in the analysis of inclusions in membranes with a nontrivial rheology. Real membranes are often strongly non-Newtonian. I will illustrate a formulation based on the Lorentz reciprocal theorem to asymptotically capture effects of non-constant surface viscosity of phospholipids that comprise most biological membranes. I will highlight the qualitative differences that ensue and potential implications in crowded membranes.

Speaker Bio

Prof. Harishankar Manikantan is an assistant professor of Chemical Engineering at the University of California, Davis. He earned his master's in Theoretical and Applied Mechanics at the University of Illinois at Urbana- Champaign in 2012, and his Ph.D. in Applied Mechanics at the University of California, San Diego in 2015 working with David Saintillan. He then began his northward migration in the UC system, stopping at UC Santa Barbara as a postdoc for 3.5 years before ending up in Davis where he is now a Hellman Fellow.