Regensburg 2010 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
BP: Fachverband Biologische Physik
BP 36: Posters: Tissue Dynamics, Charge Effects, and Anomalous Transport
BP 36.2: Poster
Thursday, March 25, 2010, 17:15–20:00, Poster B2
An Asymmetric her Gene Regulatory Network in the Segmentation Clock — •Saúl Ares1, Christian Schröter2, Luis G. Morelli1,2, Andrew C. Oates2, and Frank Jülicher1 — 1Max Planck Institute for the Physics of Complex Systems, Dresden, Germany — 2Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
The segmentation clock is a transcriptional oscillator that controls the sequential segmentation of the vertebrate body axis during embryonic development. Previous models of the zebrafish segmentation clock consisting of symmetric interactions of the cyclic genes her1 and her7 were based only on wild type gene expression data. We have combined genetic experiments studying mutations in both these genes and in the non-cyclic hes6, together with measurements of the period of oscillation of the several mutant conditions. Our results can not be explained by previous models. To understand them, we propose a new model where the her genes have distinct functions in the segmentation clock with asymmetric interactions between them. Our mathematical model is based on a genetic regulatory network where her1/hes6 and her7/hes6 heterodimers have opposing functions. This genetic network model is consistent with experiments and makes testable predictions of biochemical interactions in the clockwork. An important insight coming from our model is that heterodimer formation is a rate limiting step and hence plays a key role in control of the segmentation period.