BPS2025 Poster - Spatially Resolved Hybrid Stochastic-Deterministic Model of the Galactose Regulatory Network in Yeast S. cerevisiae

Poster Presentation ��
�� February 13, 2025
🏛️ Biophysical Society Annual Meeting 2025
📍 Los Angeles, CA
👥 Tianyu Wu, David Bianchi,…, Zaida Luthey-Schulten

We presented our latest research on spatially resolved hybrid stochastic-deterministic modeling of the galactose regulatory network in Saccharomyces cerevisiae at the Biophysical Society Annual Meeting 2025. This work addresses a major challenge in systems biology: simulating whole-cell behavior in spatially heterogeneous environments.

Using the hybrid reaction-diffusion master equation-ordinary differential equation (RDME-ODE) methodology implemented in Lattice Microbes, we modeled the galactose regulatory network with its complex 3-layer feedback loops governing galactose uptake and metabolism. This regulatory network serves as a canonical model of gene regulation, exhibiting both bistability and stochastic behavior.

Key Findings:

Exposure to 0.2% (11.1 mM) external galactose concentration leads to significant intracellular galactose increase
Parallel rise in transporter and reporter protein expression within 60 minutes
Results consistent with experimental data from Ramsey et al. (2006) and Acar et al. (2005)
Exploration of varying external galactose levels and their impact on cellular decision-making

This work demonstrates the feasibility of whole-cell modeling in eukaryotic systems and highlights the critical role of spatial heterogeneity in cellular regulatory processes. The hybrid computational framework opens new possibilities for understanding complex biological systems at unprecedented resolution.

�� Poster presented at BPS2025 Annual Meeting