Tkacik, GasperIST Austria ; Gregor, Thomas
Half a century after Lewis Wolpert's seminal conceptual advance on how cellular fates distribute in space, we provide a brief historical perspective on how the concept of positional information emerged and influenced the field of developmental biology and beyond. We focus on a modern interpretation of this concept in terms of information theory, largely centered on its application to cell specification in the early Drosophila embryo. We argue that a true physical variable (position) is encoded in local concentrations of patterning molecules, that this mapping is stochastic, and that the processes by which positions and corresponding cell fates are determined based on these concentrations need to take such stochasticity into account. With this approach, we shift the focus from biological mechanisms, molecules, genes and pathways to quantitative systems-level questions: where does positional information reside, how it is transformed and accessed during development, and what fundamental limits it is subject to?
This work was supported in part by the National Science Foundation, through the Center for the Physics of Biological Function (PHY-1734030), by the National Institutes of Health (R01GM097275) and by the Fonds zur Förderung der wissenschaftlichen Forschung (FWF P28844). Deposited in PMC for release after 12 months.
Tkačik G, Gregor T. The many bits of positional information. Development. 2021;148(2). doi:10.1242/dev.176065
Tkačik, G., & Gregor, T. (2021). The many bits of positional information. Development. The Company of Biologists. https://doi.org/10.1242/dev.176065
Tkačik, Gašper, and Thomas Gregor. “The Many Bits of Positional Information.” Development. The Company of Biologists, 2021. https://doi.org/10.1242/dev.176065.
G. Tkačik and T. Gregor, “The many bits of positional information,” Development, vol. 148, no. 2. The Company of Biologists, 2021.
Tkačik G, Gregor T. 2021. The many bits of positional information. Development. 148(2), dev176065.
Tkačik, Gašper, and Thomas Gregor. “The Many Bits of Positional Information.” Development, vol. 148, no. 2, dev176065, The Company of Biologists, 2021, doi:10.1242/dev.176065.