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Shah AM, Guo L, Morales MG, Jaichander P, Chen K, Huang H, Cano Hernandez K, Xu L, Bassel-Duby R, Olson EN, Liu N. TWIST2-mediated chromatin remodeling promotes fusion-negative rhabdomyosarcoma. SCIENCE ADVANCES 2023; 9:eade8184. [PMID: 37115930 PMCID: PMC10146891 DOI: 10.1126/sciadv.ade8184] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 03/27/2023] [Indexed: 05/03/2023]
Abstract
Rhabdomyosarcoma (RMS) is a common soft tissue sarcoma in children that resembles developing skeletal muscle. Unlike normal muscle cells, RMS cells fail to differentiate despite expression of the myogenic determination protein MYOD. The TWIST2 transcription factor is frequently overexpressed in fusion-negative RMS (FN-RMS). TWIST2 blocks differentiation by inhibiting MYOD activity in myoblasts, but its role in FN-RMS pathogenesis is incompletely understood. Here, we show that knockdown of TWIST2 enables FN-RMS cells to exit the cell cycle and undergo terminal myogenesis. TWIST2 knockdown also substantially reduces tumor growth in a mouse xenograft model of FN-RMS. Mechanistically, TWIST2 controls H3K27 acetylation at distal enhancers by interacting with the chromatin remodelers SMARCA4 and CHD3 to activate growth-related target genes and repress myogenesis-related target genes. These findings provide insights into the role of TWIST2 in maintaining an undifferentiated and tumorigenic state of FN-RMS and highlight the potential of suppressing TWIST2-regulated pathways to treat FN-RMS.
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Affiliation(s)
- Akansha M. Shah
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lei Guo
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Maria Gabriela Morales
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Priscilla Jaichander
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kenian Chen
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Huocong Huang
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Karla Cano Hernandez
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lin Xu
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rhonda Bassel-Duby
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Eric N. Olson
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ning Liu
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
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Xu J, Strasburg GM, Reed KM, Velleman SG. Temperature and Growth Selection Effects on Proliferation, Differentiation, and Adipogenic Potential of Turkey Myogenic Satellite Cells Through Frizzled-7-Mediated Wnt Planar Cell Polarity Pathway. Front Physiol 2022; 13:892887. [PMID: 35677087 PMCID: PMC9167958 DOI: 10.3389/fphys.2022.892887] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/19/2022] [Indexed: 12/30/2022] Open
Abstract
Satellite cells (SCs) are a heterogeneous population of multipotential stem cells. During the first week after hatch, satellite cell function and fate are sensitive to temperature. Wingless-type mouse mammary tumor virus integration site family/planar cell polarity (Wnt/PCP) signaling pathway is significantly affected by thermal stress in turkey pectoralis major (p. major) muscle SCs. This pathway regulates the activity of SCs through a frizzled-7 (Fzd7) cell surface receptor and two intracellular effectors, rho-associated protein kinase (ROCK) and c-Jun. The objective of the present study was to determine the effects of thermal stress, growth selection, and the Fzd7-mediated Wnt/PCP pathway on proliferation, myogenic differentiation, lipid accumulation, and expression of myogenic and adipogenic regulatory genes. These effects were evaluated in SCs isolated from the p. major muscle of 1-week faster-growing modern commercial (NC) line of turkeys as compared to SCs of a slower-growing historic Randombred Control Line 2 (RBC2) turkey line. Heat stress (43°C) increased phosphorylation of both ROCK and c-Jun with greater increases observed in the RBC2 line. Cold stress (33°C) had an inhibitory effect on both ROCK and c-Jun phosphorylation with the NC line showing greater reductions. Knockdown of the expression of Fzd7 decreased proliferation, differentiation, and expression of myogenic regulatory genes: myoblast determination factor-1 and myogenin in both lines. Both lipid accumulation and expression of adipogenic regulatory genes: peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-β, and neuropeptide-Y were suppressed with the Fzd7 knockdown. The RBC2 line was more dependent on the Fzd7-mediated Wnt/PCP pathway for proliferation, differentiation, and lipid accumulation compared to the NC line. Thus, thermal stress may affect poultry breast muscle growth potential and protein to fat ratio by altering function and fate of SCs through the Fzd7-mediated Wnt/PCP pathway in a growth-dependent manner.
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Affiliation(s)
- Jiahui Xu
- Department of Animal Sciences, The Ohio State University, Wooster, OH, United States
| | - Gale M. Strasburg
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, United States
| | - Kent M. Reed
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, United States
| | - Sandra G. Velleman
- Department of Animal Sciences, The Ohio State University, Wooster, OH, United States
- *Correspondence: Sandra G. Velleman,
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van Santen VJB, Klein-Nulend J, Bakker AD, Jaspers RT. Stiff matrices enhance myoblast proliferation, reduce differentiation, and alter the response to fluid shear stress in vitro. Cell Biochem Biophys 2022; 80:161-170. [DOI: 10.1007/s12013-021-01050-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/18/2021] [Indexed: 11/03/2022]
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He J, Mai J, Li Y, Chen L, Xu H, Zhu X, Pan Q. miR-597 inhibits breast cancer cell proliferation, migration and invasion through FOSL2. Oncol Rep 2017; 37:2672-2678. [PMID: 28393251 PMCID: PMC5428280 DOI: 10.3892/or.2017.5558] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/21/2016] [Indexed: 01/21/2023] Open
Abstract
Many reports suggest that the discovery of microRNAs (miRNAs) might provide a novel therapeutical target for many diseases, even of human cancers; however, there are no reports on the role of miR-597 in human cancers. In the present study, by detecting mRNA expression with qRT-PCR, compared with the adjacent normal tissues we found that miR-597 was significantly downregulated in breast cancer tissues. By using the MTT assay, the cell wound-healing assay and the cell invasion assay, we demonstrated that miR-597 mimics were able to suppress breast cancer cell proliferation, migration and invasion. Additionally, with flow cytometry, we found that miR-597 influenced the growth of breast cancer cells through regulating the G1-S phase transition. Furthermore, we identified one binding site for miR-597 at the 3′UTR of the FOSL2 gene, using bioinformatics methods and the luciferase reporter assay, it was confirmed that FOSL2 was a direct target of miR-597. Moreover, overexpression of FOSL2 in MDA-MB-231 and SK-BR-3 cells can block the vast majority of the miR-597 roles, suggesting that miR-597 acts as a tumor suppressor in breast cancer cells by the downregulation of FOSL2. Additionally, we also found a negative correlation between the expression of FOSL2 and miR-597 in the tumor samples. This new regulatory mechanism in breast cancer may provide another method for diagnosis and therapy.
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Affiliation(s)
- Jiangtu He
- The Research Center for Immunology, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Jieying Mai
- Department of Central Laboratory, Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China
| | - Yan Li
- Department of Clinical Laboratory, Maternal and Child Health Care of Zaozhuang, Zaozhuang, Shandong 277102, P.R. China
| | - Linyi Chen
- Department of Ophthalmology, Tai Zhou Hospital of Zhejiang Province, Taizhou, Zhejiang 317099, P.R China
| | - Hui Xu
- Department of Ophthalmology, Tai Zhou Hospital of Zhejiang Province, Taizhou, Zhejiang 317099, P.R China
| | - Xiaofei Zhu
- The Research Center for Immunology, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Qiuhui Pan
- Department of Central Laboratory, Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China
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Gurdziel K, Vogt KR, Walton KD, Schneider GK, Gumucio DL. Transcriptome of the inner circular smooth muscle of the developing mouse intestine: Evidence for regulation of visceral smooth muscle genes by the hedgehog target gene, cJun. Dev Dyn 2016; 245:614-26. [PMID: 26930384 DOI: 10.1002/dvdy.24399] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/29/2016] [Accepted: 02/16/2016] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Digestion is facilitated by coordinated contractions of the intestinal muscularis externa, a bilayered smooth muscle structure that is composed of inner circular muscles (ICM) and outer longitudinal muscles (OLM). We performed transcriptome analysis of intestinal mesenchyme tissue at E14.5, when the ICM, but not the OLM, is present, to investigate the transcriptional program of the ICM. RESULTS We identified 3967 genes enriched in E14.5 intestinal mesenchyme. The gene expression profiles were clustered and annotated to known muscle genes, identifying a muscle-enriched subcluster. Using publically available in situ data, 127 genes were verified as expressed in ICM. Examination of the promoter and regulatory regions for these co-expressed genes revealed enrichment for cJUN transcription factor binding sites, and cJUN protein was enriched in ICM. cJUN ChIP-seq, performed at E14.5, revealed that cJUN regulatory regions contain characteristics of muscle enhancers. Finally, we show that cJun is a target of Hedgehog (Hh), a signaling pathway known to be important in smooth muscle development, and identify a cJun genomic enhancer that is responsive to Hh. CONCLUSIONS This work provides the first transcriptional catalog for the developing ICM and suggests that cJun regulates gene expression in the ICM downstream of Hh signaling. Developmental Dynamics 245:614-626, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Katherine Gurdziel
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109
| | - Kyle R Vogt
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109
| | - Katherine D Walton
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109
| | - Gary K Schneider
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109
| | - Deborah L Gumucio
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109
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Jain P, Lavorgna A, Sehgal M, Gao L, Ginwala R, Sagar D, Harhaj EW, Khan ZK. Myocyte enhancer factor (MEF)-2 plays essential roles in T-cell transformation associated with HTLV-1 infection by stabilizing complex between Tax and CREB. Retrovirology 2015; 12:23. [PMID: 25809782 PMCID: PMC4374383 DOI: 10.1186/s12977-015-0140-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 01/15/2015] [Indexed: 12/17/2022] Open
Abstract
Background The exact molecular mechanisms regarding HTLV-1 Tax-mediated viral gene expression and CD4 T-cell transformation have yet to be fully delineated. Herein, utilizing virus-infected primary CD4+ T cells and the virus-producing cell line, MT-2, we describe the involvement and regulation of Myocyte enhancer factor-2 (specifically MEF-2A) during the course of HTLV-1 infection and associated disease syndrome. Results Inhibition of MEF-2 expression by shRNA and its activity by HDAC9 led to reduced viral replication and T-cell transformation in correlation with a heightened expression of MEF-2 in ATL patients. Mechanistically, MEF-2 was recruited to the viral promoter (LTR, long terminal repeat) in the context of chromatin, and constituted Tax/CREB transcriptional complex via direct binding to the HTLV-1 LTR. Furthermore, an increase in MEF-2 expression was observed upon infection in an extent similar to CREB (known Tax-interacting transcription factor), and HATs (p300, CBP, and p/CAF). Confocal imaging confirmed MEF-2 co-localization with Tax and these proteins were also shown to interact by co-immunoprecipitation. MEF-2 stabilization of Tax/CREB complex was confirmed by a novel promoter-binding assay that highlighted the involvement of NFAT (nuclear factor of activated T cells) in this process via Tax-mediated activation of calcineurin (a calcium-dependent serine-threonine phosphatase). MEF-2-integrated signaling pathways (PI3K/Akt, NF-κB, MAPK, JAK/STAT, and TGF-β) were also activated during HTLV-1 infection of primary CD4+ T cells, possibly regulating MEF-2 activity. Conclusions We demonstrate the involvement of MEF-2 in Tax-mediated LTR activation, viral replication, and T-cell transformation in correlation with its heightened expression in ATL patients through direct binding to DNA within the HTLV-1 LTR. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0140-1) contains supplementary material, which is available to authorized users.
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Alli NS, Yang EC, Miyake T, Aziz A, Collins-Hooper H, Patel K, McDermott JC. Signal-dependent fra-2 regulation in skeletal muscle reserve and satellite cells. Cell Death Dis 2013; 4:e692. [PMID: 23807221 PMCID: PMC3702306 DOI: 10.1038/cddis.2013.221] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Activator protein-1 (AP-1) is a ubiquitous transcription factor that paradoxically also has some tissue-specific functions. In skeletal muscle cells, we document that the AP-1 subunit, Fra-2, is expressed in the resident stem cells (Pax7-positive satellite cells) and also in the analogous undifferentiated ‘reserve' cell population in myogenic cultures, but not in differentiated myofiber nuclei. Silencing of Fra-2 expression enhances the expression of differentiation markers such as muscle creatine kinase and myosin heavy chain, indicating a possible role of Fra-2 in undifferentiated myogenic progenitor cells. We observed that Fra-2 is a target of cytokine-mediated extracellular signal-regulated kinase-1/2 signaling in cultured muscle cells, and extensive mass spectrometry and mutational analysis identified S320 and T322 as regulators of Fra-2 protein stability. Interestingly, Fra-2 S320 phosphorylation occurs transiently in activated satellite cells and is extinguished in myogenin-positive differentiating cells. Thus, cytokine-mediated Fra-2 expression and stabilization is linked to regulation of myogenic progenitor cells having implications for the molecular regulation of adult muscle stem cells and skeletal muscle regeneration.
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Affiliation(s)
- N S Alli
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, Canada
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Lee JH, Lee GT, Kwon SJ, Jeong J, Ha YS, Kim WJ, Kim IY. CREBZF, a novel Smad8-binding protein. Mol Cell Biochem 2012; 368:147-53. [PMID: 22707059 DOI: 10.1007/s11010-012-1353-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 05/16/2012] [Indexed: 12/25/2022]
Abstract
Smads are the secondary messengers of the transforming growth factor-β (TGF-β) signaling pathway. TGF-β receptors phosphorylate the Receptor Smads (R-Smads) upon ligand binding; activated R-Smads translocate to the nucleus and function as transcription factors. Among the R-Smads, Smads 1, 5, and 8 mainly mediate signals in the bone morphogenetic proteins (BMPs) pathways, while Smads 2/3 mediate TGF-β signaling. The regulation of Smads in the TGF-β signal pathway has been well defined, but the relationship of Smads 1, 5, and 8 to the BMP pathways has been relatively understudied. To understand the specific regulation of BMP mediating Smads, we performed yeast two-hybrid screening using the Mad homology 2(MH2) domain of Smad8 as bait. In this screening, novel Smad-binding protein, CREBZF-a basic region-leucine zipper (bZIP) transcription factor-was identified. The interaction of CREBZF and Smads 1, 5, and 8 was confirmed by immunoprecipitation in a human prostate cancer cell line. Overexpression of CREBZF inhibited the promoter activity of BMP response element and abolished the cell growth inhibition induced by BMP-6. Thus, CREBZF inhibits the function of BMP-6 by interacting with Smads. The identification of this novel Smads-binding protein, among others will help us understand the modulation of BMP-signaling pathways.
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Affiliation(s)
- Jae-Ho Lee
- Section of Urologic Oncology and the Dean and Betty Gallo Prostate Cancer Center, The Cancer Institute of New Jersey and Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA
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Stulpinas A, Imbrasaitė A, Kalvelytė AV. Daunorubicin induces cell death via activation of apoptotic signalling pathway and inactivation of survival pathway in muscle-derived stem cells. Cell Biol Toxicol 2012; 28:103-14. [PMID: 22252735 DOI: 10.1007/s10565-011-9210-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 12/26/2011] [Indexed: 02/02/2023]
Abstract
Daunorubicin (as well as other anthracyclines) is known to be toxic to heart cells and other cells in organism thus limiting its applicability in human cancer therapy. To investigate possible mechanisms of daunorubicin cytotoxicity, we used stem cell lines derived from adult rabbit skeletal muscle. Recently, we have shown that daunorubicin induces apoptotic cell death in our cell model system and distinctly influences the activity of MAP kinases. Here, we demonstrate that two widely accepted antagonistic signalling pathways namely proapoptotic JNK and prosurvival PI3K/AKT participate in apoptosis. Using the Western blot method, we observed the activation of JNK and phosphorylation of its direct target c-Jun along with inactivation of AKT and its direct target GSK in the course of programmed cell death. By means of small-molecule kinase inhibitors and transfection of cells with the genes of the components of these pathways, c-Jun and AKT, we confirm that JNK signalling pathway is proapoptotic, whereas AKT is antiapoptotic in daunorubicin-induced muscle cells. These findings could contribute to new approaches which will result in less toxicity and fewer side effects that are currently associated with the use of daunorubicin in cancer therapies.
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Affiliation(s)
- Aurimas Stulpinas
- Vilnius University Institute of Biochemistry, Mokslininkų 12, Vilnius, 08662, Lithuania.
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10
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Reinke AW, Grigoryan G, Keating AE. Identification of bZIP interaction partners of viral proteins HBZ, MEQ, BZLF1, and K-bZIP using coiled-coil arrays. Biochemistry 2010; 49:1985-97. [PMID: 20102225 DOI: 10.1021/bi902065k] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Basic-region leucine-zipper transcription factors (bZIPs) contain a segment rich in basic amino acids that can bind DNA, followed by a leucine zipper that can interact with other leucine zippers to form coiled-coil homo- or heterodimers. Several viruses encode proteins containing bZIP domains, including four that encode bZIPs lacking significant homology to any human protein. We investigated the interaction specificity of these four viral bZIPs by using coiled-coil arrays to assess self-associations as well as heterointeractions with 33 representative human bZIPs. The arrays recapitulated reported viral-human interactions and also uncovered new associations. MEQ and HBZ interacted with multiple human partners and had unique interaction profiles compared to any human bZIPs, whereas K-bZIP and BZLF1 displayed homospecificity. New interactions detected included HBZ with MAFB, MAFG, ATF2, CEBPG, and CREBZF and MEQ with NFIL3. These were confirmed in solution using circular dichroism. HBZ can heteroassociate with MAFB and MAFG in the presence of MARE-site DNA, and this interaction is dependent on the basic region of HBZ. NFIL3 and MEQ have different yet overlapping DNA-binding specificities and can form a heterocomplex with DNA. Computational design considering both affinity for MEQ and specificity with respect to other undesired bZIP-type interactions was used to generate a MEQ dimerization inhibitor. This peptide, anti-MEQ, bound MEQ both stably and specifically, as assayed using coiled-coil arrays and circular dichroism in solution. Anti-MEQ also inhibited MEQ binding to DNA. These studies can guide further investigation of the function of viral and human bZIP complexes.
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Affiliation(s)
- Aaron W Reinke
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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Abstract
Cooperation among transcription factors is central for their ability to execute specific transcriptional programmes. The AP1 complex exemplifies a network of transcription factors that function in unison under normal circumstances and during the course of tumour development and progression. This Perspective summarizes our current understanding of the changes in members of the AP1 complex and the role of ATF2 as part of this complex in tumorigenesis.
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Affiliation(s)
- Pablo Lopez-Bergami
- Instituto de Biologia y Medicina Experimental, Vuelta de Obligado 2490, Buenos Aires1428, Argentina,
| | - Eric Lau
- Signal Transduction Program, Burnham Institute for Medical Research, La Jolla, CA 92037, USA,
| | - Ze'ev Ronai
- Signal Transduction Program, Burnham Institute for Medical Research, La Jolla, CA 92037, USA
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12
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Systematic identification of mammalian regulatory motifs' target genes and functions. Nat Methods 2008; 5:347-53. [PMID: 18311145 DOI: 10.1038/nmeth.1188] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Accepted: 02/04/2008] [Indexed: 12/30/2022]
Abstract
We developed an algorithm, Lever, that systematically maps metazoan DNA regulatory motifs or motif combinations to sets of genes. Lever assesses whether the motifs are enriched in cis-regulatory modules (CRMs), predicted by our PhylCRM algorithm, in the noncoding sequences surrounding the genes. Lever analysis allows unbiased inference of functional annotations to regulatory motifs and candidate CRMs. We used human myogenic differentiation as a model system to statistically assess greater than 25,000 pairings of gene sets and motifs or motif combinations. We assigned functional annotations to candidate regulatory motifs predicted previously and identified gene sets that are likely to be co-regulated via shared regulatory motifs. Lever allows moving beyond the identification of putative regulatory motifs in mammalian genomes, toward understanding their biological roles. This approach is general and can be applied readily to any cell type, gene expression pattern or organism of interest.
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Liu C, Hadjiargyrou M. Identification and characterization of the Mustang promoter: regulation by AP-1 during myogenic differentiation. Bone 2006; 39:815-24. [PMID: 16731063 DOI: 10.1016/j.bone.2006.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 04/04/2006] [Accepted: 04/08/2006] [Indexed: 11/19/2022]
Abstract
We previously identified Mustang (musculoskeletal temporally activated novel gene) with expression exclusively in the musculoskeletal system. Although its expression is almost undetectable in intact bone, it is robustly upregulated during bone regeneration. It is also abundantly expressed in adult skeletal muscle and tendon. As such, Mustang represents a marker for these cells and thus identifying its promoter would enable us to characterize its transcriptional regulation. To this end, we have isolated and characterized a 1512-bp mouse genomic clone representing the Mustang 5'-flanking region and identified a transcription start site, a TATA box, and multiple putative transcription factor binding sites (including AP-1 and AP-2). The activity of this promoter was detected in musculoskeletal cells and embryonic fibroblasts, even exceeding levels (145%) of the control SV40 promoter (in C2C12 cells). Further, the contribution of specific AP-1 and AP-2 sites was determined with serially deleted and mutated promoter constructs. Results indicate that one of the four AP-1 sites is required for substantial transcriptional activation, as its specific deletion or mutation decreases promoter activity by 32% and 40%, respectively. In contrast, deletion of both identified AP-2 sites results in only a 12% decrease in promoter activity. We further characterized the key AP-1 site by EMSA and determined that in both proliferating and differentiating C2C12 cells, only c-Fos, Fra-2 and JunD were required for transcriptional activation. Mustang's restricted tissue specificity and strong promoter makes this gene an ideal candidate for utilization in cell lineage studies that could unveil cellular/molecular mechanisms responsible for musculoskeletal development and regeneration.
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Affiliation(s)
- Cheng Liu
- Department of Biomedical Engineering, Stony Brook University, Psychology A Building, Room 338, Stony Brook, NY 11794-2580, USA
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Neimark E, Chen F, Li X, Magid MS, Alasio TM, Frankenberg T, Sinha J, Dawson PA, Shneider BL. c-Fos is a critical mediator of inflammatory-mediated repression of the apical sodium-dependent bile acid transporter. Gastroenterology 2006; 131:554-67. [PMID: 16890608 DOI: 10.1053/j.gastro.2006.05.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Accepted: 04/27/2006] [Indexed: 02/03/2023]
Abstract
BACKGROUND & AIMS Ileal bile acid malabsorption is present in Crohn's ileitis. The molecular mechanisms of regulation of the apical sodium-dependent bile acid transporter (ASBT) by inflammatory cytokines in vitro and in vivo are investigated. METHODS Transient transfection studies of the human, mouse, and rat ASBT promoters and Northern analyses were performed in cells treated with the inflammatory cytokines and/or various activator protein-1 constructs. Rat ASBT promoter transgenic, wild-type, and c-fos-null mice were treated with indomethacin to assess the response to acute inflammation of the ileal mucosa. RESULTS In Caco-2 cells, ASBT messenger RNA expression was reduced 65% after interleukin-1beta treatment, while c-fos and c-jun were up-regulated 2-fold. Human ASBT promoter activity was enhanced by c-jun and repressed by a dominant negative c-jun, c-fos, or a dominant negative c-fos. Meanwhile, c-fos antisense treatment activated the human ASBT promoter 5-fold and not only abrogated interleukin-1beta-mediated repression but led to a paradoxical increase in ASBT promoter activity. Indomethacin-induced acute ileitis led to repression of ASBT in wild-type mice and in the transgenic rat ASBT promoter reporter, while paradoxical activation of ASBT was seen in c-fos-null mice. Indomethacin-induced ileal injury was greater in the c-fos-null mice compared with the wild-type littermates. CONCLUSIONS Human, rat, and mouse ASBT is inhibited by inflammatory cytokines via direct interactions of c-fos with the ASBT promoter.
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Affiliation(s)
- Ezequiel Neimark
- Division of Pediatric Hepatology, Department of Pediatrics, Mount Sinai School of Medicine, New York, New York 10029, USA
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Busson M, Daury L, Seyer P, Grandemange S, Pessemesse L, Casas F, Wrutniak-Cabello C, Cabello G. Avian MyoD and c-Jun coordinately induce transcriptional activity of the 3,5,3'-triiodothyronine nuclear receptor c-ErbAalpha1 in proliferating myoblasts. Endocrinology 2006; 147:3408-18. [PMID: 16556763 DOI: 10.1210/en.2006-0101] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although physical interactions with other receptors have been reported, heterodimeric complexes of T(3) nuclear receptors (TR) with retinoid X receptors (RXRs) are considered as major regulators of T(3) target gene expression. However, despite the potent T(3) influence in proliferating myoblasts, RXR isoforms are not expressed during proliferation, raising the question of the nature of the complex involved in TRalpha transcriptional activity. We have previously established that c-Jun induces TRalpha1 transcriptional activity in proliferating myoblasts not expressing RXR. This regulation is specific to the muscle lineage, suggesting the involvement of a muscle-specific factor. In this study, we found that MyoD expression in HeLa cells stimulates TRalpha1 activity, an influence potentiated by c-Jun coexpression. Similarly, in the absence of RXR, MyoD or c-Jun overexpression in myoblasts induces TRalpha1 transcriptional activity through a direct repeat 4 or an inverted palindrome 6 thyroid hormone response element. The highest rate of activity was recorded when c-Jun and MyoD were coexpressed. Using c-Jun-negative dominants, we established that MyoD influence on TRalpha1 activity needs c-Jun functionality. Furthermore, we demonstrated that TRalpha1 and MyoD physically interact in the hinge region of the receptor and the transactivation and basic helix loop helix domains of MyoD. RXR expression (spontaneously occurring at the onset of myoblast differentiation) in proliferating myoblasts abrogates these interactions. These data suggest that in the absence of RXR, TRalpha1 transcriptional activity in myoblasts is mediated through a complex including MyoD and c-Jun.
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Affiliation(s)
- Muriel Busson
- Unité d'Endocrinologie Cellulaire, Unité Mixte de Recherche Différenciation Cellulaire et Croissance, Institut National de la Recherche Agronomique, 2 place Viala, 34060 Montpellier Cedex 1, France
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Batt J, Bain J, Goncalves J, Michalski B, Plant P, Fahnestock M, Woodgett J. Differential gene expression profiling of short and long term denervated muscle. FASEB J 2005; 20:115-7. [PMID: 16291642 DOI: 10.1096/fj.04-3640fje] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Skeletal muscle function and viability are dependent upon intact innervation. Peripheral nerve injury and muscle denervation cause muscle atrophy. Time to re-innervation is one of the most important determinants of functional outcome. While short-term denervation can result in nearly fully reversible changes in muscle mass, prolonged denervation leads to irreversible muscle impairment from profound atrophy, myocyte death and fibrosis. We performed transcriptional profiling to identify genes that were altered in expression in short-term (1 month) and long-term (3 month) denervated muscle and validated the microarray data by RT-PCR and Western blotting. Genes controlling cell death, metabolism, proteolysis, stress responses and protein synthesis/translation were altered in expression in the denervated muscle. A differential pattern of expression of genes encoding cell cycle regulators and extracellular matrix components was identified that correlated with the development of irreversible post-denervation changes. Genes encoding mediators of protein degradation were differentially expressed between 1 and 3 month denervated muscle suggesting different signaling networks are recruited over time to induce and maintain muscle atrophy. Understanding of the timing and type of pathological processes that are triggered by denervation may allow the design of interventions that delay or protect muscle from loss of nerve function.
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Affiliation(s)
- Jane Batt
- Clinical Sciences Division, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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Busson M, Carazo A, Seyer P, Grandemange S, Casas F, Pessemesse L, Rouault JP, Wrutniak-Cabello C, Cabello G. Coactivation of nuclear receptors and myogenic factors induces the major BTG1 influence on muscle differentiation. Oncogene 2005; 24:1698-710. [PMID: 15674337 DOI: 10.1038/sj.onc.1208373] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The btg1 (B-cell translocation gene 1) gene coding sequence was isolated from a translocation break point in a case of B-cell chronic lymphocytic leukaemia. We have already shown that BTG1, considered as an antiproliferative protein, strongly stimulates myoblast differentiation. However, the mechanisms involved in this influence remained unknown. In cultured myoblasts, we found that BTG1 stimulates the transcriptional activity of nuclear receptors (T3 and all-trans retinoic acid receptors but not RXRalpha and PPARgamma), c-Jun and myogenic factors (CMD1, Myf5, myogenin). Immunoprecipitation experiments performed in cells or using in vitro-synthesized proteins and GST pull-down assays established that BTG1 directly interacts with T3 and all-trans retinoic acid receptors and with avian MyoD (CMD1). These interactions are mediated by the transactivation domain of each transcription factor and the A box and C-terminal part of BTG1. NCoR presence induces the ligand dependency of the interaction with nuclear receptors. Lastly, deletion of BTG1 interacting domains abrogates its ability to stimulate nuclear receptors and CMD1 activity, and its myogenic influence. In conclusion, BTG1 is a novel important coactivator involved in the regulation of myoblast differentiation. It not only stimulates the activity of myogenic factors, but also of nuclear receptors already known as positive myogenic regulators.
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Affiliation(s)
- Muriel Busson
- UMR 866 Différenciation Cellulaire et Croissance, INRA, 2 place Viala, 34060 Montpellier Cedex 1, France
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Pearson AG, Curtis MA, Waldvogel HJ, Faull RLM, Dragunow M. Activating transcription factor 2 expression in the adult human brain: Association with both neurodegeneration and neurogenesis. Neuroscience 2005; 133:437-51. [PMID: 15878807 DOI: 10.1016/j.neuroscience.2005.02.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2004] [Revised: 02/15/2005] [Accepted: 02/20/2005] [Indexed: 11/23/2022]
Abstract
Activating transcription factor 2 (ATF2) is a member of the activator protein-1 family of transcription factors, which includes c-Jun and c-Fos. ATF2 is highly expressed in the mammalian brain although little is known about its function in nerve cells. Knockout mouse studies show that this transcription factor plays a role in neuronal migration during development but over-expression of ATF2 in neuronal-like cell culture promotes nerve cell death. Using immunohistochemical techniques we demonstrate ATF2 expression in the normal human brain is neuronal, is found throughout the cerebral cortex and is particularly high in the granule cells of the hippocampus, in the brain stem, in the pigmented cells of the substantia nigra and locus coeruleus, and in the granule and molecular cell layers of the cerebellum. In contrast to normal cases, ATF2 expression is down-regulated in the hippocampus, substantia nigra pars compacta and caudate nucleus of the neurological diseases Alzheimer's, Parkinson's and Huntington's, respectively. Paradoxically, an increase in ATF2 expression was found in the subependymal layer of Huntington's disease cases, compared with normal brains; a region reported to contain increased numbers of proliferating progenitor cells in Huntington's disease. We propose ATF2 plays a role in neuronal viability in the normal brain, which is compromised in susceptible regions of neurological diseases leading to its down-regulation. In contrast, the increased expression of ATF2 in the subependymal layer of Huntington's disease suggests a role for ATF2 in some aspect of neurogenesis in the diseased brain.
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Affiliation(s)
- A G Pearson
- Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand
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Safi A, Vandromme M, Caussanel S, Valdacci L, Baas D, Vidal M, Brun G, Schaeffer L, Goillot E. Role for the pleckstrin homology domain-containing protein CKIP-1 in phosphatidylinositol 3-kinase-regulated muscle differentiation. Mol Cell Biol 2004; 24:1245-55. [PMID: 14729969 PMCID: PMC321442 DOI: 10.1128/mcb.24.3.1245-1255.2004] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Revised: 09/10/2003] [Accepted: 11/04/2003] [Indexed: 11/20/2022] Open
Abstract
In this work, we report the implication of the pleckstrin homology (PH) domain-containing protein CKIP-1 in phosphatidylinositol 3-kinase (PI3-K)-regulated muscle differentiation. CKIP-1 is upregulated during muscle differentiation in C2C12 cells. We show that CKIP-1 binds to phosphatidylinositol 3-phosphate through its PH domain and localizes to the plasma membrane in a PI3-K-dependent manner. Activation of PI3-K by insulin or expression of an active form of PI3-K p110 induces a rapid translocation of CKIP-1 to the plasma membrane. Conversely, expression of the 3-phosphoinositide phosphatase myotubularin or PI3-K inhibition by LY294002, wortmannin, or mutant p85 abolishes CKIP-1 binding to the membrane. Upon induction of differentiation in low-serum medium, CKIP-1 overexpression in C2C12 myoblasts first promotes proliferation and then stimulates the expression of myogenin and cell fusion in a manner reminiscent of the dual positive effect of insulin-like growth factors on muscle cells. Interference with the PI3-K pathway impedes the effect of CKIP-1 on C2C12 cell differentiation. Finally, silencing of CKIP-1 by RNA interference abolishes proliferation and delays myogenin expression. Altogether, these data strongly implicate CKIP-1 as a new component of PI3-K signaling in muscle differentiation.
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Affiliation(s)
- Alexias Safi
- Equipe de Biologie des Regulations Cellulaires, LBMC, CNRS UMR5665, ENS Lyon, IFR128 BioSciences Lyon-Gerland, Lyon, France
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Hu CD, Kerppola TK. Simultaneous visualization of multiple protein interactions in living cells using multicolor fluorescence complementation analysis. Nat Biotechnol 2003; 21:539-45. [PMID: 12692560 PMCID: PMC1820765 DOI: 10.1038/nbt816] [Citation(s) in RCA: 604] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2002] [Accepted: 02/03/2003] [Indexed: 11/08/2022]
Abstract
The specificity of biological regulatory mechanisms relies on selective interactions between different proteins in different cell types and in response to different extracellular signals. We describe a bimolecular fluorescence complementation (BiFC) approach for the simultaneous visualization of multiple protein interactions in the same cell. This approach is based on complementation between fragments of fluorescent proteins with different spectral characteristics. We have identified 12 bimolecular fluorescent complexes that correspond to 7 different spectral classes. Bimolecular complex formation between fragments of different fluorescent proteins did not differentially affect the dimerization efficiency of the bZIP domains of Fos and Jun or the subcellular sites of interactions between these domains. Multicolor BiFC enables visualization of interactions between different proteins in the same cell and comparison of the efficiencies of complex formation with alternative interaction partners.
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Affiliation(s)
- Chang-Deng Hu
- Howard Hughes Medical Institute and Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109-0650, USA
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Chen F, Ma L, Sartor RB, Li F, Xiong H, Sun AQ, Shneider B. Inflammatory-mediated repression of the rat ileal sodium-dependent bile acid transporter by c-fos nuclear translocation. Gastroenterology 2002; 123:2005-16. [PMID: 12454857 DOI: 10.1053/gast.2002.37055] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Ileal malabsorption of bile salts is observed in Crohn's ileitis. We define the transcriptional mechanisms involved in cytokine-mediated repression of the rat apical sodium-dependent bile acid transporter (ASBT). METHODS ASBT regulation was studied in IL-1beta-treated IEC-6 and Caco-2 cells and in indomethacin-treated rats. RESULTS Indomethacin-induced ileitis in Lewis rats leads to specific reductions in ileal ASBT messenger RNA and protein levels, whereas c-jun and c-fos are induced. The proinflammatory cytokines interleukin-1beta and tumor necrosis factor repress the activity of the ASBT promoter in Caco-2 and intestinal epithelial cell-6 cells. This effect is blocked by the proteasome inhibitor, MG-132, or by the phosphatidyl inositol 3-kinase inhibitor, wortmannin. Indomethacin (in vivo) or proinflammatory cytokine (in vitro) treatment leads to serine phosphorylation and nuclear translocation of c-fos. Mutation of a 5' activated protein (AP)-1 site inactivates the ASBT promoter, whereas mutation of the 3' site abrogates the proinflammatory cytokine-mediated repression. The 5' site binds a c-jun homodimer, whereas the 3' site binds a c-jun/c-fos heterodimer. c-Jun overexpression enhances ASBT promoter activity, whereas a dominant negative c-jun construct inactivates the promoter. c-Fos overexpression represses promoter activity. A 27 base pair cis-element from the 3' site in the ASBT promoter imparts cytokine-mediated down-regulation to a heterologous SV40 promoter construct. CONCLUSIONS The ASBT promoter contains 2 distinct cis AP-1 elements; the 5' element binds homodimeric c-jun and mediates basal transcription. Inflammation is associated with up-regulation, phosphorylation, and nuclear translocation of c-fos, which then represses ASBT promoter activity via binding of the 3' AP-1 element by a c-fos/c-jun heterodimer.
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Affiliation(s)
- Frank Chen
- Division of Pediatric Gastroenterology, Nutrition and Liver Diseases, Department of Pediatrics and the Immunobiology Center, Mount Sinai School of Medicine, New York, New York 10029, USA
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