Platform Talk and Session Co-Chair – Systems Biophysics at BPS2026

Platform Presentation & Session Co-Chair 🎤
📅 February 22, 2026
🏛️ Biophysical Society 70th Annual Meeting (BPS2026)
📍 Moscone Center, San Francisco, CA
🪑 Systems Biophysics Platform — co-chaired with Prof. Shankar Mukherji (Washington University in St. Louis)
👥 Tianyu Wu, Marie-Christin Spindler, Abner Apsley, Henry Li, Zane R. Thornburg, Julia Mahamid, Zaida Luthey-Schulten

BPS2026 Systems Biophysics platform talk — Opening the talk at the Systems Biophysics platform session, BPS2026, Moscone Center, San Francisco.

I had the distinct honor of co-chairing the Systems Biophysics platform with Professor Shankar Mukherji (Washington University in St. Louis) and presenting our latest work in the same session. Helping run a session at this level — and sharing the stage with people pushing on how we model complex biological systems — was a privilege.

The talk

Why do we need to incorporate cellular structures in cell simulation? Insights from spatially embedded simulation of the yeast galactose switch

We presented 4D simulations of the galactose switch in Saccharomyces cerevisiae built on a hybrid framework that couples reaction–diffusion master equations (RDME) for genetic information processing with ordinary differential equations (ODEs) for a simplified metabolism, running on the GPU-based Lattice Microbes platform.

What the geometry buys you:

Cell geometry is reconstructed from cryo-electron tomograms (cryo-ET), so cytosolic and ER-associated ribosomes can be counted and placed separately
That separation gives realistic ribosome availability for ER-associated translation of membrane-destined proteins such as the galactose transporter Gal2
11 mM extracellular galactose triggers expression of 10,000–15,000 transporters within 60 minutes
The maze-like ER slows Gal2 delivery to the membrane — an effect that a well-mixed model cannot produce
Multi-GPU solver performance was benchmarked across several spatial decompositions

The through-line: cellular geography is not decoration. It changes how genetic information is processed and how quickly a cell can commit to a new carbon source.

Citation

Wu, T., Spindler, M.-C., Apsley, A., Li, H., Thornburg, Z. R., Mahamid, J., & Luthey-Schulten, Z. (2026). Spatial heterogeneity alters the dynamics of the yeast galactose switch: Insights from 4D RDME–ODE hybrid simulations. Biophysical Journal, 125(4), 15a. https://doi.org/10.1016/j.bpj.2025.11.287

📄 Read the abstract in Biophysical Journal

Thanks to the organizers, and to everyone who stopped by with questions or caught me in the hallway afterwards. The community is what makes #BPS2026 worth the trip — looking forward to seeing where these conversations go.