RESUMO
CUT&Tag is a method to map the genome-wide distribution of histone modifications and some chromatin-associated proteins. CUT&Tag relies on antibody-targeted chromatin tagmentation and can easily be scaled up or automatized. This protocol provides clear experimental guidelines and helpful considerations when planning and executing CUT&Tag experiments.
Assuntos
Código das Histonas , Histonas , Animais , Histonas/genética , Histonas/metabolismo , Drosophila/genética , Drosophila/metabolismo , Cromatina/genética , GenomaRESUMO
During embryogenesis, the genome shifts from transcriptionally quiescent to extensively active in a process known as Zygotic Genome Activation (ZGA). In Drosophila, the pioneer factor Zelda is known to be essential for the progression of development; still, it regulates the activation of only a small subset of genes at ZGA. However, thousands of genes do not require Zelda, suggesting that other mechanisms exist. By conducting GRO-seq, HiC and ChIP-seq in Drosophila embryos, we demonstrate that up to 65% of zygotically activated genes are enriched for the histone variant H2A.Z. H2A.Z enrichment precedes ZGA and RNA Polymerase II loading onto chromatin. In vivo knockdown of maternally contributed Domino, a histone chaperone and ATPase, reduces H2A.Z deposition at transcription start sites, causes global downregulation of housekeeping genes at ZGA, and compromises the establishment of the 3D chromatin structure. We infer that H2A.Z is essential for the de novo establishment of transcriptional programs during ZGA via chromatin reorganization.
