Figure 6. PHF8 directly regulates the serotonin receptors Htr1a and Htr2a.

(a) ChIP primers (green bars) selected in promoter and putative enhancers of Htr1a, and Htr2a. Promoter-specific primers were designed in conserved regions within the first 300 bp of the TSS. Enhancer-specific primers were placed at conserved cerebral DNase hypersensitivity sites (HSs) (Red boxes; ENCODE/University of Washington) upstream of the TSS. For Htr2a a putative long range enhancer (∼40 kb) was selected, with Htr2a being the closest gene to this site and the next nearest gene being >100 kb away. (b) ChIP-qPCR on the neocortex with primers located in conserved regions either ∼200 bp upstream of the TSS (Promoter) or within a putative enhancer for the serotonin receptors. PHF8 occupancy is detected at the Htr1a and Htr2a loci but not at the promoter of Utf1, Mac1 nor within a gene desert. (c) Correlation between differential gene expression (y-axis; log₂[KO/WT]) by RNA-seq and differential histone mark deposition (x-axis; log₂[KO/WT]) at the TSS±3 kb when comparing WT and KO in neocortical neurons. (d) Input normalized reads show the fold enrichment of H3K4me1, H3K4me3, H3K9me2 and H3K27me2 at the serotonin receptors Htr1a, Htr1b and Htr2a.