A global change in RNA polymerase II pausing during the Drosophila midblastula transition

Elife. 2013 Aug 13;2:e00861. doi: 10.7554/eLife.00861.


Massive zygotic transcription begins in many organisms during the midblastula transition when the cell cycle of the dividing egg slows down. A few genes are transcribed before this stage but how this differential activation is accomplished is still an open question. We have performed ChIP-seq experiments on tightly staged Drosophila embryos and show that massive recruitment of RNA polymerase II (Pol II) with widespread pausing occurs de novo during the midblastula transition. However, ∼100 genes are strongly occupied by Pol II before this timepoint and most of them do not show Pol II pausing, consistent with a requirement for rapid transcription during the fast nuclear cycles. This global change in Pol II pausing correlates with distinct core promoter elements and associates a TATA-enriched promoter with the rapid early transcription. This suggests that promoters are differentially used during the zygotic genome activation, presumably because they have distinct dynamic properties. DOI:http://dx.doi.org/10.7554/eLife.00861.001.

Keywords: ChIP-seq; D. melanogaster; RNA polymerase pausing; chromatin; promoters; transcription; zygotic genome activation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blastula / growth & development*
  • Chromatin Immunoprecipitation
  • Drosophila / embryology*
  • Histones / metabolism
  • Promoter Regions, Genetic
  • RNA Polymerase II / metabolism*
  • Transcription, Genetic


  • Histones
  • RNA Polymerase II