Project description:Mutations in PHF8 are associated with X-linked mental retardationand cleft lip/cleft palate. PHF8 contains a plant homeodomain(PHD) in its N-terminus and is member of a family of JmjC-domaincontaining proteins. While PHDs can act as methyl lysine recognitionmotifs, JmjC-domains can catalyze lysine demethylation. Here,we show that PHF8 is a histone demethylase that removes repressivehistone H3 dimethyl lysine 9 marks. Our biochemical analysisrevealed specific association of the PHF8 PHD domain with histoneH3 trimethylated at lysine 4 (H3K4me3). Chromatin-immunoprecipitationfollowed by high throughput sequencing indicated that PHF8 isenriched at transcription start sites of many active or poisedgenes, mirroring the presence of RNA polymerase II (RNAPII)and of H3K4me3-bearing nucleosomes. We show that PHF8 can actas a transcriptional co-activator and its activation functionlargely depends on binding of the PHD to H3K4me3. Furthermore,we present evidence for direct interaction of PHF8 with theC-terminal domain of RNAPII. Importantly, a PHF8 disease mutantis defective in demethylation and in co-activation. This isthe first demonstration of a chromatin-modifying enzyme whichis globally recruited to promoters through its association withH3K4me3 and RNAPII. This SuperSeries is composed of the following subset Series: GSE20563: Knockdown of PHF8 in HeLa S3 cells GSE20725: ChIP-Seq of PHF8 and H3K4me3 Refer to individual Series
Project description:PHF8 is an H3K9me2 demethylase, interacts with H3K4me3 and RNA Polymerase II, is enriched at thousands of transcription start sites and can act as a transcriptional co-activator. In the following experiment we wanted to analyze the impact of PHF8-knockdown on transcript levels in HeLa cells. Three independent replicate knockdown experiments with PHF8-shA and control NT-sh were performed (6 samples in total). The two samples of each replicate experiment were hybridized in two color dye swap experiments (6 arrays in total).
Project description:PHF8 is an H3K9me2 demethylase, interacts with H3K4me3 and RNA Polymerase II, is enriched at thousands of transcription start sites and can act as a transcriptional co-activator. In the following experiment we wanted to analyze the impact of PHF8-knockdown on transcript levels in HeLa cells.