Speaker: Maciej Majka, PhD
Visiting Professor, Fullbright fellow
East Carolina University, Greenville NC, Department of Physics
Presents: Emergent Mechanisms of Stabilization in Gene Expression Patterns
Date: May 6, 2025
Time: 12:00 -1:00 PM
Location: Nanaline Duke 147
Abstract:
In the development of embryo, cells determine which genes to express by reading the local concentrations of chemical signals, called morphogens. This leads to the formation of gene expression patterns (GEPs), representing the early blueprint of the future organism. GEP formation is understood within the concept of reaction-diffusion dynamics (Turing, 1952) and positional information paradigm (Wolpert’s ‘French flag model’, 1969). However, the deeper understanding of GEPs formation and specific mechanisms maintaining their long-term presence, even after parental morphogen clues wear out, is still limited. In this talk, I will discuss novel insights into this problem coming from the recently investigated class of analytically solvable models of domain formation. The results include the classification of possible domain dynamics types; showing that patterning resembles phase transition; and identifying the exact conditions for the long-term stable coexistence of domains. Eventually, these findings are applied to explain the robustness of ‘alternate cushion’ pattern motif, emulating e.g. the ‘four gap genes pattern’ in Drosophila and investigated by large-scale realistic simulations. The ‘emergent noise control mechanism’ is identified, responsible for the significantly enhanced pattern survival time in a certain regime of parameters.
Bibliography:
- Majka, R.D.J.G. Ho, M. Zagorski, ‘Stability of pattern formation in systems with dynamic source regions’, Phys. Rev. Lett., 130, 9, 098402 (2023)
- Majka, N. B. Becker, P. R. ten Wolde, M. Zagorski, T. R. Sokolowski, ‘Stable developmental patterns of gene expression without morphogen gradients’, PLoS Comput. Biol., 20, 12, e1012555 (2024)
- D.J.G. Ho, K. Kishi, M. Majka, A. Kicheva, M. Zagorski, ‘Dynamics of morphogen source formation in a growing tissue’, PLOS Comput. Biol., 20, 10, e1012508 (2024)
