Biology
The Abdominal-B promoter tethering element mediates promoter-enhancer specificity at the Drosophila bithorax complex
Abstract
At the Drosophila bithorax complex many distinct classes of cis-regulatory modules work collectively during development to control gene expression. Abdominal-B (Abd-B) is one of three homeotic genes in the BX-C and is expressed in speciters, insulators, silencers, enhancers, promoter targeting sequences and the recently identified promoter tethering element (PTE). To activate gene expression at the endogenous complex, enhancers located >50 kb away must bypass intervening insulators to interact with the Abd-B promoter. The molecular mechanisms that allow enhancers to bypass insulators are not currently well understood. In this short article, we report on a novel mechanism for insulator bypass involving the PTE. In addition, we use bioinformatic analysis across twelve Drosophila genomes to identify putative cis-regulatory sequences that may be capable of facilitating specific promoter-enhancer interactions at the bithorax complex and propose a model for their molecular function during development. © 2007 Landes Bioscience.
