Dresden 2006 – wissenschaftliches Programm
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AKB: Biologische Physik
AKB 22: Sensory Biophysics and Signal Transduction
AKB 22.2: Vortrag
Donnerstag, 30. März 2006, 15:00–15:15, ZEU 255
Precision of Morphogen Gradients — •Tobias Bollenbach1, Periklis Pantazis2, Karsten Kruse1, Marcos González-Gaitán2, and Frank Jülicher1 — 1MPI for the Physics of Complex Systems, Nöthnitzerstr. 38, 01187 Dresden — 2MPI for Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, 01307 Dresden
A fundamental problem in the field of animal development is to understand how well-defined cellular patterns can emerge in the presence of fluctuations. A well-established means of tissue patterning is given by morphogens. These are signaling molecules that spread from a restricted source into an adjacent target tissue forming a concentration gradient. The fate of cells in the target tissue is determined by the local concentration of such morphogens. In the presence of fluctuations, it is an important question how precise the positional information encoded in a morphogen gradient can be. Here, we investigate the precision of the gradient of the morphogen Dpp in the Drosophila wing disk both experimentally and theoretically. We measure the normalized fluctuations of the Dpp gradient as a function of the distance to the source. We find that these fluctuations grow monotonously for large distances to the source, while close to the source they can decrease. Our theoretical analysis reveals that cell-to-cell variability in the target tissue can generate the observed behavior of the fluctuations. This suggests that the concentration fluctuations in the gradient reflect the random components of intercellular signaling and transport.