Links :  UCR Interdisciplinary Center for Data-driven Modeling in Biology

     UCR Math Department seminar

               PDE and Applied Math Seminar

The format of the seminar can be either in-person or online. If on zoom, please contact Dr. Jia Gou (jia.gou@ucr.edu)  for the zoom link.

Fall 2026 

Sep 29, 2:00 PM, Dr. Rohan Mehta, Elmhurst University,

Oct 06, 2:00 PM, Dr. Jing Chen ,Virginia Tech 

Oct 13, 2:00 PM, Dr. Chunyan Li, University of South Carolina

Oct 20, 12:00 PM, 

Oct 27, 2:00 PM, Dr. Wenzheng Shi, Allen Institute

Nov 03, 2:00 PM, Dr. Therese Basa Landry, UCSB

Nov 10, 2:00 PM, 

Nov 17, 2:00 PM, 

Nov 24, 10:00 AM, Dr. Albert Goldbeter , Université libre de Bruxelles 

Dec 01, 2:00 PM, Dr. Sarafa Adewale Iyaniwura, Fred Hutchinson Cancer Center

Upcoming talks:

Tuesday, October 27, 2026, 02:00 PM - 03:00 PM Pacific Time

Dr. Wenzheng Shi, Allen Institute

Title: Actin based cell chirality emerging at the boundary of 2D-microtissue directs chiral multicellular pattern formation

Abstract: The mechanisms underlying both the establishment of mirror (reflection) symmetry and deviations from it in the development of bilateral multicellular organisms remain insufficiently understood. Actin cytoskeletons of individual cells exhibit intrinsic chirality, and a strong correlation exists between single-cell actin fibres’ chiral organisation and the collective alignment of cells confined to rectangular adhesive islands (2D-microtissues). Here, we demonstrate how multicellular chiral patterns can be inferred from the chiral behaviour of actin fibres in individual cells. By analysing chiral actin systems in cells with elliptical and semicircular shapes, representing inner and boundary positions within 2D-microtissues, we defined the rules of chiral motile behaviour and formulated two models of cell alignment: (i) chiral rotation of inner cells and (ii) chiral tilting of boundary cells relative to island edges. In both models, neighbouring cells are mutually aligned. Systematic variation of island area and aspect ratio, combined with dynamic observations, revealed the primary role of boundary cells. Chiral order first emerged at tissue boundaries and then propagated inward. This outside-in mechanism also explains how intrinsically chiral cells can build mirror-symmetric tissues in bilateral organisms: either by reversing cell chirality in one half or by enlarging the tissue to minimise boundary influence.

Bio: Wenzheng Shi is a Scientist at the Allen Institute in Seattle. An applied mathematician by training, he works at the interface between mathematical modeling and experimental cell biology, developing theory and computational methods that recover the hidden mechanics of living cells from the way they move.

His research spans scales. At the molecular scale, he showed how septin proteins sense membrane curvature as an emergent property of their multiscale assembly. At the cellular scale, he reconstructed a full nonlinear model of a migrating cell's leading edge, recovering reaction rates, forces, and feedbacks directly from unperturbed imaging data. At the tissue scale, he explained how the handedness of single cells propagates into left-right order across a whole tissue. He also develops machine-learning methods for recovering stochastic differential equations from trajectory data, a general engine for the inference problems that recur throughout his biological work.

Shi earned his Ph.D. in Applied Physics from the University of North Carolina at Chapel Hill, and before joining the Allen Institute he was a Courant Instructor and Assistant Professor at the Courant Institute of Mathematical Sciences at New York University.

Previous talks: