EDRC edition:23 location:Barcelona date:16th-19th October 2013
The correct execution of a developmental program is directed by the binding of transcription factors to cis-regulatory modules, which tightly control gene expression levels in a spatio-temporal manner. On the other hand, changes in regulatory interactions are considered as important drivers of diversity. Drosophila eye development is a well-studied model of cell fate determination, however the network of regulatory interactions underlying eye specification is largely unknown. A current challenge is to decipher the regulatory interactions between TF, cis-regulatory modules and target genes and to study the evolution of regulatory interactions.
We integrated comparative analyses at the level of chromatin marks (FAIRE-seq), motif discovery (i-cisTarget) and gene expression (RNA-seq) across Drosophila species, namely D.melanogaster, D.pseudoobscura and D.virilis.
Making use of the collection of Janelia GAL4 lines we observe that conserved FAIRE-seq peaks across species improves the recovery of eye-specific enhancers. Next, we perform motif discovery on the conserved peaks, using the tool i-cisTarget, and we identify key eye-specific regulators such as Glass, Atonal and Rotund. These findings allow us to draw a conserved gene regulatory network underlying photoreceptor cell development across Drosophila species.
Finally, we are classifying the FAIRE-seq peaks as conserved or divergent across Drosophila species and investigate their effects on changes in gene expression between species.