How do developing zebrafish embryos organize their genome? Kaaij et al. show that, early in development, when there is no transcription, the genome is highly structured; however, when the zygotic genome is activated, this organization is lost. Later in development, the genome again adopts a structured organization.
Kaaij, L. J. T., van der Weide, R. H., Ketting, R. F., & de Wit, E. (2018). Systemic Loss and Gain of Chromatin Architecture throughout Zebrafish Development. Cell Reports, 24(1), 1-10.e4. https://doi.org/10.1016/j.celrep.2018.06.003