mRNA-seq of H3.3 mutant (K9A; K27A; K79A) and control mESCs

Mouse embryonic stem cells (i.e., mESCs; line ESC 129-B13) were genetically modified using CRISPR-Cas9 to mutate the H3f3b locus, in order to carry homozygous lysine-to-alanine substitution of residues K9, K27 or K79. Two control mESC lines carrying knock-out of the H3f3a gene were used as background for the editing. To compare the transcriptional profiles of the H3.3 mutant and control mESC lines, three independent replicates per condition were grown and RNA was extracted. After quality assessment of the RNA, messenger RNA was isolated using the NEBNext Poly(A) mRNA Magnetic Isolation Module (New England BioLabs) and sequencing libraries were prepared using the NEBNext Ultra II RNA Library Preparation Kit for Illumina (New England BioLabs). Sequencing was performed on a NextSeq500 platform in single-end mode (75bp reads).