Evolving Mechanisms of Morphogenesis: on the Interplay between Differential Adhesion and Cell Differentiation

Abstract

Di!erential cell adhesion, mediated by e.g. integrin and cadherins/catenines, plays an important role in morphogenesis and it has been shown that there is intimate cross-talk between their expression and modi"cation, and inter-cellular signalling, cell di!erentiation, cell growth and apoptosis. In this paper, we introduce and use a formal model to explore the morphogenetic potential of the interplay between these processes. We demonstrate the formation of interesting morphologies. Initiated by cell di!erentiation, di!erential cell adhesion leads to a long transient of cell migrations, e.g. engul"ng and intercalation of cells and cell layers. This transient can be sustained dynamically by further cell di!erentiation, and by cell growth/division and cell death which are triggered by the (also long range) forces (stretching and squeezing) generated by the cell adhesion. We study the interrelation between modes of cell di!erentiation and modes of morphogenesis. We use an evolutionary process to zoom in on gene-regulation networks which lead to cell di!erentiation. Morphogenesis is not selected for but appears as a side-e!ect. The evolutionary dynamics shows the hallmarks of evolution on a rugged landscape, including long neutral paths. We show that a combinatorially large set of morphologies occurs in the vicinity of a neutral path which sustains cell di!erentiation. Thus, an almost linear molecular phylogeny gives rise to mosaic evolution on the morphological level. Academic Press

Simulation of single-species bacterial-biofilm growth using the Glazier-Graner-Hogeweg model and the CompuCell3D modeling environment

“…GGH applications include models of Hydra vulgaris regeneration, cell motility [62], cell deformation [72], chick embryo mesenchymal chondrogenesis [17,44], growth [71] and cell motility [63], tumor growth [47,77], embryonic convergent extension [86], vasculogenesis [57], avascular tumor growth [27], cancer invasion [79,80], aggregation, slug behavior and culmination in Dictyostelium discoideum [46,53,54,55,74], the liquid-like behavior of chick-cell aggregates [10], chick limb growth [71], engineering biological structures using self-assembly [45,65], directional sorting of chemotactic cells [49], evolutionary mechanisms [40,41,42], foams [48,73], and viscous flow [22]. Figure 1 Interaction descriptions and dynamics define how the various objects behave both biologically and physically.…”

“…Adding constraints to the effective energy can describe many other cell properties, including osmotic pressure and membrane area [17,44], the average shape of the cells [57,86], chemotaxis [40,54], viscosity and advective diffusion [22], rigid-body motion [6], and cell compartments for the simulation of polarized cells, e.g., in epithelia [11].…”

On Cellular Automaton Approaches to Modeling Biological Cells

“…Therefore we must modify the classical Boltzmann index evolution dynamics to include an explicit dissipation. Hogeweg et al changed the probability for accepting index reassignments to reflect this dissipation [59]:…”

A computational model of chemotaxis-based cell aggregation

“…A discussion of how cell-centered simulations like CPM can help to explain aspects of developmental biology can be found in Merks and Glazier (2005). Some models in this category (Hogeweg, 2000(Hogeweg, , 2002Tozeren et al, 2005) use cellular automata (Ilachinski, 2001;Wolfram, 1984) to model cell motility and differentiation in order to simulate tumor growth (Dormann and Deutsch, 2002;Patel et al, 2001) and embryogenesis (Longo et al, 2004).…”

“…There has been some use of Genetic Algorithms (GAs) (Goldberg, 1989) with both grid based and hybrid computational models for simulating cell differentiation (Hogeweg, 2000(Hogeweg, , 2002, morphogenesis (Kumar, 2004), organogenesis (Chaturvedi et al, 2005) and embryogenesis (Longo et al, 2004).…”