Nascent Transcriptome of Cycloheximide (CHX)-arrested Xenopus laevis Embryos from 5-7.5 hpf

To characterize the effect of cell cyle elongation on nascent transcription during zygotic genome activation (ZGA) of Xenopus laevis embryos, we microinjected 5-ethynyl uridine (EU) into 1-cell stage embryos and treated the embryos with 0.2 mg/ml of cycloheximide (CHX) to arrest them in interphase from 5 hpf to 7.5 hpf. Control and CHX-arrested embryos were collected for isolating total RNAs, followed by biotinylation using disulfide biotin azide via click reaction and purification of nascent transcripts using streptavidin beads. Libraries were constructed and sequenced on illumina NextSeq 500. Two replicates of embryos from one clutch were treated with CHX from 5 hpf to 7.5 hpf. EU labeled nascent RNAs from both replicates of control and CHX-arrested embryos were sequenced.