Spatial and temporal cues are required to specify neuronal diversity, but how these cues are integrated in neural progenitors remains unknown. Drosophila progenitors (neuroblasts) are a good model: they are individually identifiable with relevant spatial and temporal transcription factors known. Here we test whether spatial/temporal factors act independently or sequentially in neuroblasts. We used Targeted-DamID to identify genomic binding sites of the Hunchback temporal factor in two neuroblasts (NB5-6 and NB7-4) that make different progeny. Hunchback targets were different in each neuroblast, ruling out the independent specification model. Moreover, each neuroblast had distinct open chromatin domains, which correlated with differential Hb-bound loci in each neuroblast. Importantly, Gsb/Pax3 spatial factor binding correlated with open chromatin in NB5-6, but not NB7-4. Our data support a model in which early-acting spatial factors establish neuroblast-specific open chromatin domains, leading to neuroblast-specific temporal factor binding and the production of different neurons in each neuroblast lineage.
Data are available via the NCBI Gene Expression Omnibus database (accession number GSE123272).
Neuroblast-specific chromatin landscapes allow integration of spatial and temporal cues to generate neuronal diversity in DrosophilaNCBI Gene Expression Omnibus, GSE123272.
Binding site turnover produces pervasive quantitative changes in TF binding between closely related Drosophila speciesNCBI Gene Expression Omnibus, GSE20369.
- Chris Q Doe
- Chris Q Doe
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Gail Mandel, Oregon Health and Science University, United States
© 2019, Sen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.