GSE103625 Multiple chromatin factors determine multiple waves of 3D contacts organizein the Drosophila genome during embryogenesis

We describe the dynamic and stepwise progression of chromatin organization into TADs that correlates with zygotic genome activation. The stability of TAD boundaries during embryogenesis is supported by insulator proteins. Moreover we characterize two types of chromatin loops that emerge with different developmental dynamics. Active loops can be detected before midblastula transition and are formed between highly transcribed genes over long distances, whereas repressive chromatin loops are formed after midblastula transition between Polycomb response elements (PREs) within Polycomb domains. CRISPR/Cas9 genome engineering revealed the functional importance of PRE-mediated looping contacts for the establishment of Polycomb domains and target gene repression. Together, our results provide fundamental insights in the dynamics and function of chromatin organization during development.

Source: GEO: Gene Expression Omnibus - June 8, 2018 Category: Genetics & Stem Cells Tags: Other Drosophila melanogaster Source Type: research