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

✍ Scribed by P. HOGEWEG

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 833 KB
• Volume: 203
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.2000.1087

✦ Synopsis

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.