Dataset Information

The density of regulatory information is a major determinant of evolutionary constraint on non-coding DNA in Drosophila [CUT&RUN]

ABSTRACT: Evolutionary analyses have estimated that ~60% of nucleotides in intergenic regions of the Drosophila melanogaster genome are functionally relevant, suggesting that regulatory information may be encoded more densely in intergenic regions than has been revealed by most functional dissections of regulatory DNA. Here, we approached this issue through a functional dissection of the regulatory region of the gene shavenbaby (svb). Most of the ~90 kilobases of this large regulatory region is highly conserved in the genus Drosophila, though characterized enhancers occupy a small fraction of this region. By analyzing the regulation of svb in different contexts of Drosophila development, we found that the regulatory information that drives svb expression in the abdominal pupal epidermis is organized in a different way than the elements that drive svb expression in the embryonic epidermis. While in the embryonic epidermis svb is activated by compact enhancers separated by large inactive DNA regions, svb expression in the pupal epidermis is driven by regulatory information distributed over broader regions of svb cis-regulatory DNA. In the same vein, we observed that other developmental genes also display a dense distribution of putative regulatory elements in their regulatory regions. Furthermore, we found that a large percentage of conserved non-coding DNA of the Drosophila genome is contained within regions of open chromatin. These results suggest that part of the evolutionary constraint on non-coding DNA of Drosophila is explained by the density of regulatory information, which may be greater than previously appreciated.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE253027 | GEO | 2024/01/16

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Developmental programs are implemented by regulatory interactions between Transcription Factors (TFs) and their target genes, which remain yet poorly understood. While recent studies have focused on regulatory cascades of TFs that govern early development, little is known on how these are selected and controlled the ultimate cellular effectors of terminal differentiation. We addressed this question during late Drosophila embryogenesis when the finely tuned expression of a TF, Ovo/Shavenbaby (Svb), triggers the morphological differentiation of epidermal trichomes. We used chromatin immunoprecipitation and microarray profiling to identify Svb downstream target genes and show that Svb directly regulates a large set of terminal effectors of trichome formation. Functional assays delineated 18 Svb bound sequences driving specific expression of trichome effectors, with highly similar pattern and dynamics. Coupling computational modeling to functional dissection, we further investigated the regulatory logic of these enhancers. We find that these “terminal” enhancers harbor remarkable features with respect to their functional architectures. Trichome enhancers display weak if any clustering of Svb binding sites. Moreover, the in vivo function of each site relies on its intimate context, with a critical importance of the nucleotides flanking Svb binding sites. Finally, we identify additional cis-regulatory motifs, showing a broad diversity of positioning among trichome enhancers, and that critically contribute to their activity. Taken together, these results show that trichome formation is underpinned by unexpectedly diverse modes of regulation, and shed light on the functional architecture of enhancers governing a terminal differentiation program. Chromatin from 12-14 hour old embryos expressing svb tagged with GFP (Kondo T, Plaza S, Zanet J, Benrabah E, Valenti P, Hashimoto Y, Kobayashi S, Payre F, Kageyama Y: Small peptides switch the transcriptional activity of Shavenbaby during Drosophila embryogenesis. Science 2010, 329:336-339) was collected in duplicate. Chromatin was immunoprecipitated using an antiGFP antibody and input chromatin was used as a control.

Dataset Information

The density of regulatory information is a major determinant of evolutionary constraint on non-coding DNA in Drosophila [CUT&RUN]

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure