Anterior-posterior positional information in the absence of a strong Bicoid gradient.

ABSTRACT: The Bicoid (Bcd) transcription factor is distributed as a long-range concentration gradient along the anterior posterior (AP) axis of the Drosophila embryo. Bcd is required for the activation of a series of target genes, which are expressed at specific positions within the gradient. Here we directly tested whether different concentration thresholds within the Bcd gradient establish the relative positions of its target genes by flattening the gradient and systematically varying expression levels. Genome-wide expression profiles were used to estimate the total number of Bcd target genes, and a general correlation was found between the Bcd concentration required for activation and the positions where target genes are expressed in wild-type embryos. However, concentrations required for target

SUBMITTER: Ochoa-Espinosa A 

PROVIDER: S-EPMC2656164 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature