Project description:Mono-methylation of histone H3 on lysine 4 (H3K4me1) and acetylation of histone H3 on lysine 27 (H3K27ac) are histone modifications that are highly enriched over the body of actively transcribed genes and enhancers. Although in yeast all H3K4 methylation patterns including H3K4me1 are implemented by Set1/COMPASS, there are three classes of COMPASS-like complexes in Drosophila that could carry out H3K4me1 on enhancers: dSet1, Trithorax and Trithorax-related (Trr). Here, we report that Trr, the Drosophila homolog of mammalian Mll3/4, can function as a major H3K4 mono-methyltransferase on enhancers in vivo. Loss of Trr results in a global decrease of H3K4me1 and H3K27ac in various tissues. Assays with the cut wing margin enhancer imply a functional role for Trr in enhancer-mediated processes. A genome-wide analysis demonstrates that Trr is required for H3K4me1 and H3K27ac on chromatin signatures that resemble the histone modification patterns described for enhancers. Since Trr and mammalian Mll3/4 complexes are distinguished by bearing a unique subunit, the H3K27 demethylase UTX, we propose a model in which the H3K4 mono-methyltransferase Trr, and the H3K27 demethylase, UTX, cooperate to regulate the transition from inactive/poised to active enhancers. ChIP-seq of Trr, LPT, UTX in Drosophila S2 Cells. ChIP-seq of H3K4me1, H3K4me3, H3K27ac, H3K27me3 in WT and Trr knock-down Drosophila S2 cells. ChIP-seq of H3K4me1, H3K27me3 in LPT knock-down Drosophila S2 cells. ChIP-seq of LPT and UTX in Trr knock-down Drosophila S2 cells. ChIP-seq of H3K4me1 and H3K27me3 in MLL1(+/+), MLL1(-/-), MLL3(+/+), and MLL3(-/-) Mouse Embryonic Fibroblasts (MEFs).
Project description:Our objective was to identify candidate genes that contribute to the long 31-hour circadian period previously observed in DGRP_892. We performed transcriptional profiling of whole fly heads from two genotypes: DGRP_892, and Canton-S B, a line with a normal 24-hour circadian period. We collected fly heads every two hours over a 24-hour period. We quantified differential expression among genotype, time, and sex.
Project description:To measure the response to gene dose, we performed mRNA-Seq of fly heads with molecularly defined deletions constructed from DrosDel deficiency lines (Ryder et al. Genetics 2007, 177(1):615-29) on the Illumina HiSeq 2000 platform.
