Positional Information and Cell Fate Determination in the Early Drosophila Embryo.

During early development in Drosophila, the spatial information of maternal gradients is translated into discrete transcriptional states determining cell fate. Information transfer depends on reproducibility of the gradients themselves, as well as the ability of cells to accurately measure and utilize morphogen concentrations in biologically meaning ways. In the following essay, these issues are discussed in context of the Bicoid gradient.