Age-related changes in H3K9me3 and H3K27me3 in Caenorhabditis elegans somatic tissues

To examine age-related changes in repressive histone modifications (H3K9me3 and H3K27me3) in young (day2) and aged somatic tissues (day12) of C. elegans, we performed chromatin-immunoprecipitation followed by sequencing (ChIP-seq) in germlineless glp-1(e2141) worms grown at the non-permissive temperature (25C). Indexed DNA libraries (average fragment length ~200bp) were sequenced on the Illumina HiSeq (single-end 50-bp) or NextSeq500 (single-end 75-bp) platforms. Two independent ChIP-seq experiments were performed. The first experiment generated two biological replicates of H3 and H3K27me3 ChIP-seq. The second experiment generated two biological replicates of H3 and H3K9me3 ChIP-seq.