EPSRC Network on Evolvability in Biology & Software Systems

Evolvability, Genetics & Development in Natural and Constructed Systems: Abstracts of the EPSRC Evolvability Network Symposium

Tewin Bury Farm Hotel, Hertfordshire, England, UK
26-28 August 2003


University of Hertfordshire Computer Science Technical Report 389
C. L. Nehaniv, P. J. Bentley & S. Kumar (Editors)

Pattern Formation and Pattern Regulation during Early Embryonic Development

Pattern Formation and Pattern Regulation during Early Embryonic Development

HANS MEINHARDT

Max-Planck-Institut für Entwicklungsbiologie
Spemannstr. 35
D-72076 Tübingen
Germany

hans.meinhardt@tuebingen.mpg.de


Development of higher organisms depends on a complex chain of molecular interactions in which positive and negative feedback loops play a crucial role. It will be shown that models can provide a considerable help to understand the underlying complex machinery. Organizing regions for the main body axes can be generated by local self-enhancement and long-range inhibition. Such patterns have self-regulatory properties; regeneration of missing parts is a straightforward property. The formation of a bilateral-symmetric body plan requires generation of an orthogonal coordinate system and especially the formation of a midline - an organizing region that has a long extension in one dimension and a short extension perpendicular to the first. It will be shown that this is difficult patterning problem and that vertebrates, insects and flatworms found very different strategies to solve it. Other models will deal with the stable activation of genes, patterning of somites and the initiation of legs and wings in pairs with correct orientation and handedness. Computer simulations will illustrate that the models describes many observations in fine details.

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