Project description:Total RNA was isolated from proliferating and senescent IMR90 cells to compare gene-expression to the changes in nucleolus-association in proliferating and senescent IMR90 cells.
Project description:Cellular senescence is a stable proliferation arrest that suppresses tumorigenesis. Histone chaperone HIRA deposits nucleosome-destabilizing histone variant H3.3 into chromatin in a DNA replication-independent manner. Histone H3.3 and a subset of other typically M-bM-^@M-^\replication-dependentM-bM-^@M-^] core histones were expressed in non-proliferating senescent cells, the latter linked to alternative mRNA splicing and polyadenylation. Senescent cells incorporated newly-synthesized histones into chromatin, partially dependent on HIRA. HIRA and newly-deposited histone H3.3 co-localized at promoters of expressed genes, and their distribution shifted between proliferating and senescent cells, paralleling changes in gene expression. In senescent cells, gene promoters showed exceptional enrichment of a histone acetylation linked to open and dynamic chromatin, H4K16ac. Abundance of H4K16ac depended on HIRA. In the mouse, inactivation of HIRA downregulated H4K16ac and dramatically enhanced oncogene-induced hyperplasia. To conclude, HIRA controls a previously undefined dynamic non-canonical H4K16ac-decorated chromatin landscape in senescence, and also plays an unanticipated role in suppression of oncogene-induced neoplasia. Examination of HIRA protein binding alongside histone modification H4K16ac and H3.3 in proliferating and senescent IMR90 cells
Project description:H3K9me3 ChIPseq in Proliferating and Senescent IMR90s We used ChIP-seq to examine the global binding of H3K9me3 in human IMR90 replicative senescence (RS) and oncogene-induced (OIS)
Project description:Nucleolus-associated DNA was isolated from cross-linked proliferating and senescent IMR90 human fibroblasts and hybridized against genomic (1) or non-nucleolar (2) DNA to map nucleolus-associated chromosomal domains.
Project description:RNAseq replicate in Proliferating and Senescent IMR90s We used RNAseq to examine RNA levels in human IMR90 replicative senescence (RS)
Project description:Gene expression changes were compared in proliferating and senescent human IMR90 cells, with or without TSA treatment. Method: RNA was extracted, in triplicate, then sequenced with an Illumina NextSeq 500 sequencer. Sequence reads passing the quality control filters were aligned using Tophat2 and then analysed with Cufflinks.