Mutual inactivation of Notch receptors and ligands facilitates developmental patterning.
Bottom Line: It generally remains unclear, however, how this mutual inactivation and the resulting switching behavior can impact developmental patterning circuits.For lateral inhibition, we find that mutual inactivation speeds up patterning dynamics, relieves the need for cooperative regulatory interactions, and expands the range of parameter values that permit pattern formation, compared to canonical models.Together, these results provide a framework for analysis of more complex Notch-dependent developmental systems.
Affiliation: Howard Hughes Medical Institute, California Institute of Technology, Pasadena, California, USA.Show MeSH
Related in: MedlinePlus
Mentions: A striking aspect of the Drosophila wing vein system is observed in the heterozygous mutants of Notch and Delta (e.g. single copies of the Notch and Delta genes). While heterozygous mutants of Notch (Notch+/−) or Delta (Delta+/−) alone exhibit mutant phenotypes (causing thicker veins), the Notch+/− Delta+/− double mutant restores the wild-type phenotype , , . More generally, several mutant phenotypes seem to depend on the ratio between the copy numbers of the Notch and DSL genes . This ratiometric dependence of the vein width cannot be derived from the several known feedbacks operating in the Drosophila wing vein, but emerges automatically from the MI model. This is because the position of the Notch signaling band occurs where Notch and DSL production rates are equal. This position remains unchanged when both rates are multiplied by the same factor. By the same reasoning, the vein width (distance between side bands) increases with increasing ratios between the effective copy numbers of DSL and Notch, as shown in Figs. 3A, S2.
Affiliation: Howard Hughes Medical Institute, California Institute of Technology, Pasadena, California, USA.