Project description:Depending on the cellular context, TF expression can vary dramatically both spatially and temporally. These differences in expression patterns can result in tissue-specific differences in TF binding to downstream targets. To identify targets on a tissue-specific basis, Targeted DamID (TaDa) has been recently introduced to generate TF binding profiles in various models including C. elegans. However, TaDa suffers from portability such that a new promoter-TF fusion transgene must be constructed for every new experimental condition of interest. Here, we adapt NanoDam for usage in C. elegans, which relies on the use of endogenous TF-GFP knock-ins, a plethora of which have already been generated by the community. We report that NanoDam single copy transgenes consisting of lowly expressed, tissue-specific GFP nanobody-Dam fusions, when combined with endogenous GFP-tagged alleles of TFs, results in robust, tissue-specific profiling. Using an endogenous GFP-tagged allele of EGL-43/EVI1, we performed NanoDam profiling of two disparate tissue types, the anchor cell (AC) and dopaminergic neurons, and identify targets unique to each and shared by both cell types. We also identify two GATA TFs, ELT-6 and EGL-18, as novel regulators of AC invasion. Taken together, we demonstrate that NanoDam is capable of profiling endogenous GFP-tagged TFs to identify novel downstream targets in specific cell types of C. elegans.
Project description:The C. elegans homolog of the Evi1 proto-oncogene, egl-43, coordinates G1 cell cycle arrest with pro-invasive gene expression during anchor cell invasion by regulating the expression of fos-1, and lin-12.
Project description:To identify genes whose expression in Caenorhabditis elegans is regulated by unc-43/CamKII or egl-8/PLCbeta during adulthood, we performed an exploratory whole transcriptome RNA-sequencing (RNA-seq) study on unc-43(gf), unc-43(-), egl-8(-) and corresponding unc-43(+)/egl-8(+) control worms. To further account for potential influences of genetic background on unc-43/egl-8 function, these experiments were conducted in long-lived insulin-receptor defective [daf-2(-)], as well as in otherwise wildtype [i.e daf-2(+)] strains.
Project description:This SuperSeries is composed of the following subset Series: GSE30971: The Histone Methyltransferase Wbp7 Controls Macrophage Function through GPI Glycolipid Anchor Synthesis. [Expression Profile] GSE30972: The Histone Methyltransferase Wbp7 Controls Macrophage Function through GPI Glycolipid Anchor Synthesis. [ChIP_seq] Refer to individual Series
Project description:Histone methyltransferases catalyze site-specific deposition of methyl groups, enabling recruitment of transcriptional regulators. In mammals, trimethylation of lysine 4 in histone H3, a modification localized at the transcription start sites of active genes, is catalyzed by six enzymes (SET1a and SET1b, MLL1M-bM-^@M-^SMLL4) whose specific functions are largely unknown. By using a genomic approach, we found that in macrophages, MLL4 (also known as Wbp7) was required for the expression of Pigp, an essential component of the GPI-GlcNAc transferase, the enzyme catalyzing the first step of glycosylphosphatidylinositol (GPI) anchor synthesis. Impaired Pigp expression in Wbp7-/- macrophages abolished GPI anchor-dependent loading of proteins on the cell membrane. Consistently, loss of GPI-anchored CD14, the coreceptor for lipopolysaccharide (LPS) and other bacterial molecules, markedly attenuated LPS-triggered intracellular signals and gene expression changes. These data link a histone-modifying enzyme to a biosynthetic pathway and indicate a specialized biological role for Wbp7 in macrophage function and antimicrobial response. Chromatin immuno-precipitations of H3 histone try-methylated on lysine 4 followed by multiparallel sequencing performed in murine bone marrow-derive macrophages (BMDM). Experiments carried out in untreated cells as well as in cells treated for 4hrs with lipopolysaccharide (LPS), for both Wbp7+/- (HET) and Wbp7-/- (KO) mice.
Project description:MicroRNAs (miRNAs) play important roles in a wide range of cellular processes. Aberrant regulation of miRNA genes contributes to human diseases, including cancer. The TAR DNA binding protein 43 (TDP-43), a DNA/RNA binding protein associated with neurodegeneration, is involved in miRNA biogenesis. Here, we systematically examined miRNAs whose expression levels are regulated by TDP-43 using RNA-Seq coupled with siRNA-mediated knockdown approach. TDP-43 knocking down affected the expression of a number of miRNAs. Alterations in isomiR patterns and miRNA arm selection after TDP-43 knockdown suggest a role of TDP-43 in miRNA editing. We examined correlation of selected TDP-43 associated miRNAs and their candidate target genes in human cancers. Our data reveal highly complex roles of TDP-43 in regulating different miRNAs and their target genes. Our results suggest that TDP-43 may promote migration of lung cancer cells by regulating miR-423-3p expression. On the other hand, TDP-43 increases miR-500a-3p expression and binds to the mature miR-500a-3p sequence. Low expression of miR-500a-3p was associated with poor survival of lung cancer patients, suggesting that TDP-43 may have a suppressive role in cancer by regulating miR-500a-3p. Our experiments reveal that cancer-associated genes LIF and PAPPA may be targets of miR-500a-3p. Together with other studies, our work suggests that TDP-43-regulated miRNAs may play multi-facet roles in the pathogenesis of cancer.
Project description:TDP-43 aggregation and redistribution have been recognised as a hallmark of amyotrophic lateral sclerosis, frontotemporal dementia and other neurological disorders. While TDP-43 has been studied extensively in neuronal tissues, TDP-43 inclusions have also been described in the muscle of inclusion body myositis patients, highlighting the need to understand the role of TDP-43 beyond the central nervous system. Using RNA-seq we performed the first direct comparison of TDP-43-mediated transcription and alternative splicing in muscle (C2C12) and neuronal (NSC34) mouse cells. Our results clearly show that TDP-43 displays a tissue-characteristic behaviour targeting unique transcripts in each cell type. This is not due to variable transcript abundance but rather due to cell-specific expression of RNA-binding proteins, which influences TDP-43 performance. Among splicing events commonly dysregulated in both cell lines, we identified some that are TDP-43-dependent also in human cells and show that inclusion levels of these alternative sequences appear to be altered in affected tissues of FTLD and IBM patients. We therefore propose that TDP-43 dysfunction, reflected in aberrant splicing, contributes to disease development but it does so in a tissue-specific manner.