Key Spec Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|H, R, M, Yeast (S. cerevisiae)||WB, ChIP-seq||M||Purified||Monoclonal Antibody|
|Presentation||Purified mouse IgG1 in buffer containing 0.1M Tris-glycine, pH 7.4, 0.15M NaCl, 0.05% sodium azide before the addition of glycerol to 30%.|
|Safety Information according to GHS|
|Material Size||200 µg|
|Reference overview||Application||Species||Pub Med ID|
|miR-142-5p and miR-130a-3p are regulated by IL-4 and IL-13 and control profibrogenic macrophage program.|
Su, S; Zhao, Q; He, C; Huang, D; Liu, J; Chen, F; Chen, J; Liao, JY; Cui, X; Zeng, Y; Yao, H; Su, F; Liu, Q; Jiang, S; Song, E
Nature communications 6 8523 2015
Macrophages play a pivotal role in tissue fibrogenesis, which underlies the pathogenesis of many end-stage chronic inflammatory diseases. MicroRNAs are key regulators of immune cell functions, but their roles in macrophage's fibrogenesis have not been characterized. Here we show that IL-4 and IL-13 induce miR-142-5p and downregulate miR-130a-3p in macrophages; these changes sustain the profibrogenic effect of macrophages. In vitro, miR-142-5p mimic prolongs STAT6 phosphorylation by targeting its negative regulator, SOCS1. Blocking miR-130a relieves its inhibition of PPARγ, which coordinates STAT6 signalling. In vivo, inhibiting miR-142-5p and increasing miR-130a-3p expression with locked nucleic acid-modified oligonucleotides inhibits CCL4-induced liver fibrosis and bleomycin-induced lung fibrosis in mice. Furthermore, macrophages from the tissue samples of patients with liver cirrhosis and idiopathic pulmonary fibrosis display increased miR-142-5p and decreased miR-130a-3p expression. Therefore, miR-142-5p and miR-130a-3p regulate macrophage profibrogenic gene expression in chronic inflammation.
|Epigenetic basis of opiate suppression of Bdnf gene expression in the ventral tegmental area.|
Koo, JW; Mazei-Robison, MS; LaPlant, Q; Egervari, G; Braunscheidel, KM; Adank, DN; Ferguson, D; Feng, J; Sun, H; Scobie, KN; Damez-Werno, DM; Ribeiro, E; Peña, CJ; Walker, D; Bagot, RC; Cahill, ME; Anderson, SA; Labonté, B; Hodes, GE; Browne, H; Chadwick, B; Robison, AJ; Vialou, VF; Dias, C; Lorsch, Z; Mouzon, E; Lobo, MK; Dietz, DM; Russo, SJ; Neve, RL; Hurd, YL; Nestler, EJ
Nature neuroscience 18 415-22 2015
Brain-derived neurotrophic factor (BDNF) has a crucial role in modulating neural and behavioral plasticity to drugs of abuse. We found a persistent downregulation of exon-specific Bdnf expression in the ventral tegmental area (VTA) in response to chronic opiate exposure, which was mediated by specific epigenetic modifications at the corresponding Bdnf gene promoters. Exposure to chronic morphine increased stalling of RNA polymerase II at these Bdnf promoters in VTA and altered permissive and repressive histone modifications and occupancy of their regulatory proteins at the specific promoters. Furthermore, we found that morphine suppressed binding of phospho-CREB (cAMP response element binding protein) to Bdnf promoters in VTA, which resulted from enrichment of trimethylated H3K27 at the promoters, and that decreased NURR1 (nuclear receptor related-1) expression also contributed to Bdnf repression and associated behavioral plasticity to morphine. Our findings suggest previously unknown epigenetic mechanisms of morphine-induced molecular and behavioral neuroadaptations.
|Insulin-response epigenetic activation of Egr-1 and JunB genes at the nuclear periphery by A-type lamin-associated pY19-Caveolin-2 in the inner nuclear membrane.|
Jeong, K; Kwon, H; Lee, J; Jang, D; Pak, Y
Nucleic Acids Res 43 3114-27 2015
Insulin controls transcription to sustain its physiologic effects for the organism to adapt to environmental changes added to genetic predisposition. Nevertheless, insulin-induced transcriptional regulation by epigenetic factors and in defined nuclear territory remains elusive. Here we show that inner nuclear membrane (INM)-integrated caveolin-2 (Cav-2) regulates insulin-response epigenetic activation of Egr-1 and JunB genes at the nuclear periphery. INM-targeted pY19-Cav-2 in response to insulin associates specifically with the A-type lamin, disengages the repressed Egr-1 and JunB promoters from lamin A/C through disassembly of H3K9me3, and facilitates assembly of H3K9ac, H3K18ac and H3K27ac by recruitment of GCN5 and p300 and the subsequent enrichment of RNA polymerase II (Pol II) on the promoters at the nuclear periphery. Our findings show that Cav-2 is an epigenetic regulator of histone H3 modifications, and provide novel mechanisms of insulin-response epigenetic activation at the nuclear periphery.
|An anti-silencer- and SATB1-dependent chromatin hub regulates Rag1 and Rag2 gene expression during thymocyte development.|
Hao, B; Naik, AK; Watanabe, A; Tanaka, H; Chen, L; Richards, HW; Kondo, M; Taniuchi, I; Kohwi, Y; Kohwi-Shigematsu, T; Krangel, MS
The Journal of experimental medicine 212 809-24 2015
Rag1 and Rag2 gene expression in CD4(+)CD8(+) double-positive (DP) thymocytes depends on the activity of a distant anti-silencer element (ASE) that counteracts the activity of an intergenic silencer. However, the mechanistic basis for ASE activity is unknown. Here, we show that the ASE physically interacts with the distant Rag1 and Rag2 gene promoters in DP thymocytes, bringing the two promoters together to form an active chromatin hub. Moreover, we show that the ASE functions as a classical enhancer that can potently activate these promoters in the absence of the silencer or other locus elements. In thymocytes lacking the chromatin organizer SATB1, we identified a partial defect in Tcra gene rearrangement that was associated with reduced expression of Rag1 and Rag2 at the DP stage. SATB1 binds to the ASE and Rag promoters, facilitating inclusion of Rag2 in the chromatin hub and the loading of RNA polymerase II to both the Rag1 and Rag2 promoters. Our results provide a novel framework for understanding ASE function and demonstrate a novel role for SATB1 as a regulator of Rag locus organization and gene expression in DP thymocytes.
|Dgcr8 and Dicer are essential for sex chromosome integrity during meiosis in males.|
Modzelewski, AJ; Hilz, S; Crate, EA; Schweidenback, CT; Fogarty, EA; Grenier, JK; Freire, R; Cohen, PE; Grimson, A
Journal of cell science 128 2314-27 2015
Small RNAs play crucial roles in regulating gene expression during mammalian meiosis. To investigate the function of microRNAs (miRNAs) and small interfering RNAs (siRNAs) during meiosis in males, we generated germ-cell-specific conditional deletions of Dgcr8 and Dicer in mice. Analysis of spermatocytes from both conditional knockout lines revealed that there were frequent chromosomal fusions during meiosis, always involving one or both sex chromosomes. RNA sequencing indicates upregulation of Atm in spermatocytes from miRNA-deficient mice, and immunofluorescence imaging demonstrates an increased abundance of activated ATM kinase and mislocalization of phosphorylated MDC1, an ATM phosphorylation substrate. The Atm 3'UTR contains many potential microRNA target sites, and, notably, target sites for several miRNAs depleted in both conditional knockout mice were highly effective at promoting repression. RNF8, a telomere-associated protein whose localization is controlled by the MDC1-ATM kinase cascade, normally associates with the sex chromosomes during pachytene, but in both conditional knockouts redistributed to the autosomes. Taken together, these results suggest that Atm dysregulation in microRNA-deficient germ lines contributes to the redistribution of proteins involved in chromosomal stability from the sex chromosomes to the autosomes, resulting in sex chromosome fusions during meiotic prophase I.
|The Tat Inhibitor Didehydro-Cortistatin A Prevents HIV-1 Reactivation from Latency.|
Mousseau, G; Kessing, CF; Fromentin, R; Trautmann, L; Chomont, N; Valente, ST
mBio 6 e00465 2015
Antiretroviral therapy (ART) inhibits HIV-1 replication, but the virus persists in latently infected resting memory CD4(+) T cells susceptible to viral reactivation. The virus-encoded early gene product Tat activates transcription of the viral genome and promotes exponential viral production. Here we show that the Tat inhibitor didehydro-cortistatin A (dCA), unlike other antiretrovirals, reduces residual levels of viral transcription in several models of HIV latency, breaks the Tat-mediated transcriptional feedback loop, and establishes a nearly permanent state of latency, which greatly diminishes the capacity for virus reactivation. Importantly, treatment with dCA induces inactivation of viral transcription even after its removal, suggesting that the HIV promoter is epigenetically repressed. Critically, dCA inhibits viral reactivation upon CD3/CD28 or prostratin stimulation of latently infected CD4(+) T cells from HIV-infected subjects receiving suppressive ART. Our results suggest that inclusion of a Tat inhibitor in current ART regimens may contribute to a functional HIV-1 cure by reducing low-level viremia and preventing viral reactivation from latent reservoirs.Antiretroviral therapy (ART) reduces HIV-1 replication to very low levels, but the virus persists in latently infected memory CD4(+) T cells, representing a long-lasting source of resurgent virus upon ART interruption. Based on the mode of action of didehydro-cortistatin A (dCA), a Tat-dependent transcription inhibitor, our work highlights an alternative approach to current HIV-1 eradication strategies to decrease the latent reservoir. In our model, dCA blocks the Tat feedback loop initiated after low-level basal reactivation, blocking transcriptional elongation and hence viral production from latently infected cells. Therefore, dCA combined with ART would be aimed at delaying or halting ongoing viral replication, reactivation, and replenishment of the latent viral reservoir. Thus, the latent pool of cells in an infected individual would be stabilized, and death of the long-lived infected memory T cells would result in a continuous decay of this pool over time, possibly culminating in the long-awaited sterilizing cure.
|Analysis of Histones H3 and H4 Reveals Novel and Conserved Post-Translational Modifications in Sugarcane.|
Moraes, I; Yuan, ZF; Liu, S; Souza, GM; Garcia, BA; Casas-Mollano, JA
PloS one 10 e0134586 2015
Histones are the main structural components of the nucleosome, hence targets of many regulatory proteins that mediate processes involving changes in chromatin. The functional outcome of many pathways is "written" in the histones in the form of post-translational modifications that determine the final gene expression readout. As a result, modifications, alone or in combination, are important determinants of chromatin states. Histone modifications are accomplished by the addition of different chemical groups such as methyl, acetyl and phosphate. Thus, identifying and characterizing these modifications and the proteins related to them is the initial step to understanding the mechanisms of gene regulation and in the future may even provide tools for breeding programs. Several studies over the past years have contributed to increase our knowledge of epigenetic gene regulation in model organisms like Arabidopsis, yet this field remains relatively unexplored in crops. In this study we identified and initially characterized histones H3 and H4 in the monocot crop sugarcane. We discovered a number of histone genes by searching the sugarcane ESTs database. The proteins encoded correspond to canonical histones, and their variants. We also purified bulk histones and used them to map post-translational modifications in the histones H3 and H4 using mass spectrometry. Several modifications conserved in other plants, and also novel modified residues, were identified. In particular, we report O-acetylation of serine, threonine and tyrosine, a recently identified modification conserved in several eukaryotes. Additionally, the sub-nuclear localization of some well-studied modifications (i.e., H3K4me3, H3K9me2, H3K27me3, H3K9ac, H3T3ph) is described and compared to other plant species. To our knowledge, this is the first report of histones H3 and H4 as well as their post-translational modifications in sugarcane, and will provide a starting point for the study of chromatin regulation in this crop.
|Mammalian E-type cyclins control chromosome pairing, telomere stability and CDK2 localization in male meiosis.|
Martinerie, L; Manterola, M; Chung, SS; Panigrahi, SK; Weisbach, M; Vasileva, A; Geng, Y; Sicinski, P; Wolgemuth, DJ
PLoS genetics 10 e1004165 2014
Loss of function of cyclin E1 or E2, important regulators of the mitotic cell cycle, yields viable mice, but E2-deficient males display reduced fertility. To elucidate the role of E-type cyclins during spermatogenesis, we characterized their expression patterns and produced additional deletions of Ccne1 and Ccne2 alleles in the germline, revealing unexpected meiotic functions. While Ccne2 mRNA and protein are abundantly expressed in spermatocytes, Ccne1 mRNA is present but its protein is detected only at low levels. However, abundant levels of cyclin E1 protein are detected in spermatocytes deficient in cyclin E2 protein. Additional depletion of E-type cyclins in the germline resulted in increasingly enhanced spermatogenic abnormalities and corresponding decreased fertility and loss of germ cells by apoptosis. Profound meiotic defects were observed in spermatocytes, including abnormal pairing and synapsis of homologous chromosomes, heterologous chromosome associations, unrepaired double-strand DNA breaks, disruptions in telomeric structure and defects in cyclin-dependent-kinase 2 localization. These results highlight a new role for E-type cyclins as important regulators of male meiosis.
|XBP1 promotes triple-negative breast cancer by controlling the HIF1α pathway.|
Chen, X; Iliopoulos, D; Zhang, Q; Tang, Q; Greenblatt, MB; Hatziapostolou, M; Lim, E; Tam, WL; Ni, M; Chen, Y; Mai, J; Shen, H; Hu, DZ; Adoro, S; Hu, B; Song, M; Tan, C; Landis, MD; Ferrari, M; Shin, SJ; Brown, M; Chang, JC; Liu, XS; Glimcher, LH
Nature 508 103-7 2014
Cancer cells induce a set of adaptive response pathways to survive in the face of stressors due to inadequate vascularization. One such adaptive pathway is the unfolded protein (UPR) or endoplasmic reticulum (ER) stress response mediated in part by the ER-localized transmembrane sensor IRE1 (ref. 2) and its substrate XBP1 (ref. 3). Previous studies report UPR activation in various human tumours, but the role of XBP1 in cancer progression in mammary epithelial cells is largely unknown. Triple-negative breast cancer (TNBC)--a form of breast cancer in which tumour cells do not express the genes for oestrogen receptor, progesterone receptor and HER2 (also called ERBB2 or NEU)--is a highly aggressive malignancy with limited treatment options. Here we report that XBP1 is activated in TNBC and has a pivotal role in the tumorigenicity and progression of this human breast cancer subtype. In breast cancer cell line models, depletion of XBP1 inhibited tumour growth and tumour relapse and reduced the CD44(high)CD24(low) population. Hypoxia-inducing factor 1α (HIF1α) is known to be hyperactivated in TNBCs. Genome-wide mapping of the XBP1 transcriptional regulatory network revealed that XBP1 drives TNBC tumorigenicity by assembling a transcriptional complex with HIF1α that regulates the expression of HIF1α targets via the recruitment of RNA polymerase II. Analysis of independent cohorts of patients with TNBC revealed a specific XBP1 gene expression signature that was highly correlated with HIF1α and hypoxia-driven signatures and that strongly associated with poor prognosis. Our findings reveal a key function for the XBP1 branch of the UPR in TNBC and indicate that targeting this pathway may offer alternative treatment strategies for this aggressive subtype of breast cancer.
|O-GlcNAcase Expression is Sensitive to Changes in O-GlcNAc Homeostasis.|
Zhang, Z; Tan, EP; VandenHull, NJ; Peterson, KR; Slawson, C
Frontiers in endocrinology 5 206 2014
O-linked N-acetylglucosamine (O-GlcNAc) is a post-translational modification involving an attachment of a single β-N-acetylglucosamine moiety to serine or threonine residues in nuclear and cytoplasmic proteins. Cellular O-GlcNAc levels are regulated by two enzymes: O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), which add and remove the modification, respectively. The levels of O-GlcNAc can rapidly change in response to fluctuations in the extracellular environment; however, O-GlcNAcylation returns to a baseline level quickly after stimulus removal. This process termed O-GlcNAc homeostasis appears to be critical to the regulation of many cellular functions including cell cycle progress, stress response, and gene transcription. Disruptions in O-GlcNAc homeostasis are proposed to lead to the development of diseases, such as cancer, diabetes, and Alzheimer's disease. O-GlcNAc homeostasis is correlated with the expression of OGT and OGA. We reason that alterations in O-GlcNAc levels affect OGA and OGT transcription. We treated several human cell lines with Thiamet-G (TMG, an OGA inhibitor) to increase overall O-GlcNAc levels resulting in decreased OGT protein expression and increased OGA protein expression. OGT transcript levels slightly declined with TMG treatment, but OGA transcript levels were significantly increased. Pretreating cells with protein translation inhibitor cycloheximide did not stabilize OGT or OGA protein expression in the presence of TMG; nor did TMG stabilize OGT and OGA mRNA levels when cells were treated with RNA transcription inhibitor actinomycin D. Finally, we performed RNA Polymerase II chromatin immunoprecipitation at the OGA promoter and found that RNA Pol II occupancy at the transcription start site was lower after prolonged TMG treatment. Together, these data suggest that OGA transcription was sensitive to changes in O-GlcNAc homeostasis and was potentially regulated by O-GlcNAc.