Developmental processes are highly dependent on transcriptional regulation by RNA polymerase II, which initiates transcription at the core promoter. The dorsal-ventral gene regulatory network (GRN) includes multiple genes that are activated by different nuclear concentrations of the Dorsal transcription factor along the dorsal-ventral axis. Downstream core promoter element (DPE)-containing genes are conserved and highly prevalent among Dorsal target genes. Moreover, the DPE motif is functional in multiple Dorsal target genes, as mutation of the DPE results in the loss of transcriptional activity. Furthermore, analysis of hybrid enhancer-promoter constructs reveals that the core promoter composition plays a pivotal role in the transcriptional output. Importantly, we provide in vivo evidence that expression driven by the homeotic Antennapedia P2 promoter during Drosophila embryogenesis is dependent on the DPE. Taken together, we propose that transcriptional regulation results from the interplay between enhancers and core promoter composition, thus establishing a novel dimension in developmental GRNs.
Bibliographical noteFunding Information:
We thank Ron Wides for invaluable advice. We thank Dan and Ron Even for graphic design assistance. We thank Doron Ginsberg, Diana Ideses, Hila Shir, Adi Kedmi, Yehuda Danino, and Avital Ovadia-Shochat for critical reading of the manuscript. We thank Albert Courey and Norbert Perrimon for the generous gift of reagents. This research was supported by grants from the Israel Science Foundation to T.J-G. (no. 798/10) and the European Union Seventh Framework Programme (Marie Curie International Reintegration Grant) to T.J.-G. (no. 256491).
- Core promoter
- Gene expression
- Gene regulatory network
- RNA polymerase II
- Transcriptional regulation