The histone H3 lysine 4 presenter WDR5 induces N-Myc target gene transcription and promotes neuroblastoma [gene expression]
ABSTRACT: WDR5 is an important co-factor for N-Myc-regulated transcriptional activation and tumorigenesis We analysed whether WDR5 siRNAs modulate gene expression Neuroblastoma BE(2)-C cells were treated with control siRNA, WDR5 siRNA-1, and WDR5 siRNA-2 for 40 hours, and subjected to differential gene expression studies with Affymetrix microarrays.
Project description:WDR5 is an important co-factor for N-Myc-regulated transcriptional activation and tumorigenesis Using ChIP-Seq, We profiled key epigenetic marks H3K4 trimethylation in BE(2)-C neuroblastoma cells transfected with control siRNA or WDR5 siRNA-1 at N-Myc target gene promoters The results showed knockdown WDR5 significantly reduced H3K4me3 at 93.2% of N-Myc binding promoters, but only at 53.5% of N-Myc non-binding promoters. Identification of Histone H3K4 trimethylation and N-Myc binding sites in BE(2)-C cells transfected with control siRNA or WDR5 siRNA-1.
Project description:WDR5 (WD repeat domain 5) plays an important role in the epigenetic regulation of gene transcription, involing in regulation of embryonic stem cell and cancer cell.Bladder cancer is one of the most common cancers that cause approximately 150,000 deaths per year worldwide.The goal of this study is to identify the target genes of WDR5 in bladder cancer.Our results inditcate that the genes regulated by WDR5 involved in a variety of biological functions, such as proliferation and anti-apoptosis. Bladder cancer cell line UM-UC-3 was transfected with the contol siRNA or two different WDR5 siRNA for 48h. The RNA of the transfected cells was extracted and hybridized on Affymetrix microarrays. We indentified the putative target genes of WDR5 in both WDR5 siRNA by comparing the diferent expressed genes among control, si-WDR5-2 and si-WDR5-3. We futher validated the data of microarray in UM-UC-3 and T24 by RT-qPCR and Western bloting.
Project description:Here we delineate the roles of RNA binding for WDR5 function on chromatin state and murine embryonic stem cell (ESC) maintenance. Examination of global transcriptional changes and mapping genome-wide transcription factors occupancy at distinct time points during the transdifferentiation process
Project description:The antagonistic actions of Polycomb and Trithorax are responsible for proper cell fate determination in mammalian tissues. In the epidermis, a self-renewing epithelium, previous work has shown that release from Polycomb repression only partially explains differentiation gene activation. We now show that Trithorax is also a key regulator of epidermal differentiation, not only through activation of genes repressed by Polycomb in progenitor cells, but also through activation of genes independent of regulation by Polycomb. The differentiation associated transcription factor GRHL3/GET1 recruits the ubiquitously expressed Trithorax complex to a subset of differentiation genes. Examination of WDR5 and GRHL3 binding in human differentited primary keratinocytes (NHEK). High calcium medium was added to NHEK cells at 50% confluency to induce differentiation. Cells were collected for ChIP 24 hours after addition of high calcium medium. ChIP with Wdr5 and Grhl3 antibodies, and an input control were sequenced.
Project description:Although reprogramming of somatic cells to generate inducible pluripotent stem cells (iPSCs) is associated with remarkable epigenetic changes, the role and mechanisms of epigenetic factors in this process remains poorly understood. Here we describe identification of Jmjd3 as a potent negative regulator of reprogramming. Jmjd3-deficient MEFs produced significantly more iPSC colonies than did wild-type cells, while ectopic expression of Jmjd3 markedly inhibited reprogramming. We further show that the inhibitory effects of Jmjd3 are produced through both histone demethylase-dependent and -independent pathways acting in concert. The latter pathway is entirely novel and involved Jmjd3 targeting of PHF20 for ubiquitination and degradation by recruiting an E3 ligase Trim26. Importantly, PHF20-deficient MEFs could not be converted to fully reprogrammed iPSCs, even with knockdown of Jmjd3, Ink4a or p21, indicating dominant effects of this protein on reprogramming. Our findings identify a previously unrecognized role of Jmjd3 in reprogramming and provide molecular insight into the mechanisms by which the Jmjd3-PHF20 axis controls the reprogramming process. This study was an examination of phf20 and wdr5 binding patterns in embryonic stem cells, using a ChIP-Sequencing methodology with antibodies for each of these factors in the cell lines indicated.
Project description:The bromodomain inhibitor JQ1 and the histone deacetylase inhibitor panobinostat induce synergistic anticancer effects We analyzed whether JQ1 and panobinostat synergistically modulate gene expression Neuroblastoma SK-N-BE(2) cells were treated with vehicle control, 1 microM JQ1, 10 nM panobinostat, or combination of JQ1 and panobinostat for 6 hours, and subjected to differential gene expression studies with Affymetrix microarrays.
Project description:N-Myc oncoprotein induces neuroblastoma by modulating gene transcription, and long noncoding RNAs exert biological effects by regulating gene expression. We analysed whether N-Myc and the long noncoding RNA lncMycN mediate the expression of common subsets of genes. Neuroblastoma Kelly cells were transfected with control siRNA, N-Myc siRNA-1, N-Myc siRNA-2, lncMycN siRNA-1 or lncMycN siRNA-2. RNA was extracted from the cells 48 hours after siRNA transfections, and subjected to differential gene expression studies with Affymetrix microarrays.
Project description:WD repeat domain 5 (WDR5) plays an important role in various biological functions through the epigenetic regulation of gene transcription. However, the oncogenic effect of WDR5 in leukemia remains largely unknown. Here, we found WDR5 expression is increased in leukemia patients. High expression of WDR5 is associated with high risk leukemia; Patients with WDR5 and MLL1 high expression have poor complete remission rate. We further identified the global genomic binding of WDR5 in leukemic cells and found the genomic co-localization of WDR5 binding with H3K4me3 enrichment. Moreover, WDR5 knockdown by shRNA suppresses cell proliferation, induces apoptosis, inhibits the expression of WDR5 targets, and blocks the H3K4me3 enrichment on the promoter of its targets. We also observed the positive correlation of WDR5 expression with these targets in the cohort study of leukemia patients. Our data reveal that WDR5 may have oncogenic effect and WDR5-mediated H3K4 methylation plays an important role in leukemogenesis. Overall design: Examine the genome-wide binding of WDR5 and H3K4me3 in RS4;11 and THP-1 leukemic cells.
Project description:Upon androgen stimulation, PKN1-mediated histone H3 threonine 11 phosphorylation (H3T11P) promotes AR target genes activation. However, the underlying mechanism is not completely understood. Here, we show that WDR5, a subunit of the SET1/MLL complex, interacts with H3T11P and this interaction facilitates the recruitment of the SET1/MLL complex and subsequent H3K4 trimethylation (H3K4me3). Using ChIP-seq, we find that androgen stimulation results in a six-fold increase in the number of H3T11P-marked regions and induces WDR5 colocalization to one third of H3T11P-enriched promoters, thus establishing a genome-wide relationship between H3T11P and recruitment of WDR5. Accordingly, PKN1 knock-down or chemical inhibition severely blocks WDR5 association and H3K4me3 on AR target genes. Finally, WDR5 is critical in prostate cancer cell proliferation, and is hyperexpressed in human prostate cancers. Together, these results identify WDR5 as a critical epigenomic integrator of histone phosphorylation and methylation and a major driver of androgen-dependent prostate cancer cell proliferation. Identification of Histone 3 threonine 11 phosphorylation (H3T11P) marks and WDR5 binding sites in LNCaP cells treated with R1881 ligand (androgen) or solvent control.