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Piccinno E, Scalavino V, Labarile N, De Marinis L, Armentano R, Giannelli G, Serino G. Identification of a Novel miR-195-5p/PNN Axis in Colorectal Cancer. Int J Mol Sci 2024; 25:5980. [PMID: 38892168 PMCID: PMC11172886 DOI: 10.3390/ijms25115980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Revised: 05/24/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024] Open
Abstract
Pinin (PNN) is a desmosome-associated protein that reinforces the organization of keratin intermediate filaments and stabilizes the anchoring of the cytoskeleton network to the lateral surface of the plasma membrane. The aberrant expression of PNN affects the strength of cell adhesion as well as modifies the intracellular signal transduction pathways leading to the onset of CRC. In our previous studies, we characterized the role of miR-195-5p in the regulation of desmosome junctions and in CRC progression. Here, with the aim of investigating additional mechanisms related to the desmosome complex, we identified PNN as a miR-195-5p putative target. Using a public data repository, we found that PNN was a negative prognostic factor and was overexpressed in colon cancer tissues from stage 1 of the disease. Then, we assessed PNN expression in CRC tissue specimens, confirming the overexpression of PNN in tumor sections. The increase in intracellular levels of miR-195-5p revealed a significant decrease in PNN at the mRNA and protein levels. As a consequence of PNN regulation by miR-195-5p, the expression of KRT8 and KRT19, closely connected to PNN, was affected. Finally, we investigated the in vivo effect of miR-195-5p on PNN expression in the colon of AOM/DSS-treated mice. In conclusion, we have revealed a new mechanism driven by miR-195-5p in the regulation of desmosome components, suggesting a potential pharmacological target for CRC therapy.
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Affiliation(s)
| | | | | | | | | | | | - Grazia Serino
- National Institute of Gastroenterology S. De Bellis, IRCCS Research Hospital, Via Turi 27, 70013 Castellana Grotte, BA, Italy; (E.P.); (V.S.); (N.L.); (L.D.M.); (R.A.); (G.G.)
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2
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Li X, Bai Z, Li Z, Wang J, Yan X. Toosendanin Restrains Idiopathic Pulmonary Fibrosis by Inhibiting ZEB1/CTBP1 Interaction. Curr Mol Med 2024; 24:123-133. [PMID: 37138491 PMCID: PMC10804237 DOI: 10.2174/1566524023666230501205149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/23/2023] [Accepted: 03/08/2023] [Indexed: 05/05/2023]
Abstract
BACKGROUND Extensive deposition of extracellular matrix (ECM) in idiopathic pulmonary fibrosis (IPF) is due to hyperactivation and proliferation of pulmonary fibroblasts. However, the exact mechanism is not clear. OBJECTIVE This study focused on the role of CTBP1 in lung fibroblast function, elaborated its regulation mechanism, and analyzed the relationship between CTBP1 and ZEB1. Meanwhile, the antipulmonary fibrosis effect and its molecular mechanism of Toosendanin were studied. METHODS Human IPF fibroblast cell lines (LL-97A and LL-29) and normal fibroblast cell lines (LL-24) were cultured in vitro. The cells were stimulated with FCS, PDGF-BB, IGF-1, and TGF-β1, respectively. BrdU detected cell proliferation. The mRNA expression of CTBP1 and ZEB1 was detected by QRT-PCR. Western blotting was used to detect the expression of COL1A1, COL3A1, LN, FN, and α-SMA proteins. An animal model of pulmonary fibrosis was established to analyze the effects of CTBP1 silencing on pulmonary fibrosis and lung function in mice. RESULTS CTBP1 was up-regulated in IPF lung fibroblasts. Silencing CTBP1 inhibits growth factor-driven proliferation and activation of lung fibroblasts. Overexpression of CTBP1 promotes growth factor-driven proliferation and activation of lung fibroblasts. Silencing CTBP1 reduced the degree of pulmonary fibrosis in mice with pulmonary fibrosis. Western blot, CO-IP, and BrdU assays confirmed that CTBP1 interacts with ZEB1 and promotes the activation of lung fibroblasts. Toosendanin can inhibit the ZEB1/CTBP1protein interaction and further inhibit the progression of pulmonary fibrosis. CONCLUSION CTBP1 can promote the activation and proliferation of lung fibroblasts through ZEB1. CTBP1 promotes lung fibroblast activation through ZEB1, thereby increasing excessive deposition of ECM and aggravating IPF. Toosendanin may be a potential treatment for pulmonary fibrosis. The results of this study provide a new basis for clarifying the molecular mechanism of pulmonary fibrosis and developing new therapeutic targets.
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Affiliation(s)
- Xingbin Li
- Department of Respiratory and Critical Care Medicine, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050005, China
- Department of Respiratory and Critical Care Medicine, Hebei Chest Hospital, Shijiazhuang, Hebei, 050041,China
| | - Zina Bai
- Department of Respiratory and Critical Care Medicine, Hebei Chest Hospital, Shijiazhuang, Hebei, 050041,China
| | - Zhensheng Li
- Department of Respiratory and Critical Care Medicine, Hebei Chest Hospital, Shijiazhuang, Hebei, 050041,China
| | - Jun Wang
- Department of Respiratory and Critical Care Medicine, Hebei Chest Hospital, Shijiazhuang, Hebei, 050041,China
| | - Xixin Yan
- Department of Respiratory and Critical Care Medicine, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050005, China
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Melano I, Lo YC, Su WC. Characterization of host substrates of SARS-CoV-2 main protease. Front Microbiol 2023; 14:1251705. [PMID: 37670988 PMCID: PMC10475589 DOI: 10.3389/fmicb.2023.1251705] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 07/31/2023] [Indexed: 09/07/2023] Open
Abstract
The main protease (Mpro) plays a crucial role in coronavirus, as it cleaves viral polyproteins and host cellular proteins to ensure successful replication. In this review, we discuss the preference in the recognition sequence of Mpro based on sequence-based studies and structural information and highlight the recent advances in computational and experimental approaches that have aided in discovering novel Mpro substrates. In addition, we provide an overview of the current understanding of Mpro host substrates and their implications for viral replication and pathogenesis. As Mpro has emerged as a promising target for the development of antiviral drugs, further insight into its substrate specificity may contribute to the design of specific inhibitors.
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Affiliation(s)
- Ivonne Melano
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Yan-Chung Lo
- Sinphar Pharmaceutical Co., Ltd., Sinphar Group, Yilan, Taiwan
| | - Wen-Chi Su
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
- International Master’s Program of Biomedical Sciences, China Medical University, Taichung, Taiwan
- Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
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4
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Jaiswal A, Singh R. CtBP: A global regulator of balancing acts and homeostases. Biochim Biophys Acta Rev Cancer 2023; 1878:188886. [PMID: 37001619 DOI: 10.1016/j.bbcan.2023.188886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/31/2023]
Abstract
The classical role of C-terminal binding protein (CtBP) is that of a global corepressor. However, its exact mechanism of repression is not known. In this review, we elucidate the repression motif used by CtBP. Further, we provide other unifying features of its mechanism of action. For example, in the presence of a high NADH/NAD+ ratio in the cell, causing a low glycolytic condition, the NADH-bound dimeric form of CtBP causes global repression, maintaining balances and homeostases of many cellular processes, under the cell surveillance of p53 and NFkB. In contrast, in the presence of a low NADH/NAD+ ratio, causing a high glycolytic condition, the NADH-free monomeric form of CtBP blocks p53 function and NFkB-mediated transcription. Further, a low NADH/NAD+ ratio upsets the homeostases and balances in the absence of the cell surveillances of p53 and NFkB, causing global instability, the dominant outcome of CtBP's action in carcinogenesis, in cells in a high glycolytic state.
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The Long and the Short of It: NEAT1 and Cancer Cell Metabolism. Cancers (Basel) 2022; 14:cancers14184388. [PMID: 36139550 PMCID: PMC9497099 DOI: 10.3390/cancers14184388] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 09/05/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Altered metabolism is a hallmark of most cancers. The way that cancer cells regulate their energy production to fuel constant proliferation has been of interest with the hope that it may be exploited therapeutically. The long noncoding RNA, NEAT1, is often dysregulated in tumours. NEAT1 RNA can be transcribed as two isoforms with different lengths, with each variant responsible for different functions. This review explores how the isoforms contribute to cancer metabolism. Abstract The long noncoding RNA NEAT1 is known to be heavily dysregulated in many cancers. A single exon gene produces two isoforms, NEAT1_1 and NEAT1_2, through alternative 3′-end processing. As the longer isoform, NEAT1_2 is an essential scaffold for nuclear paraspeckle formation. It was previously thought that the short NEAT1_1 isoform only exists to keep the NEAT1 locus active for rapid paraspeckle formation. However, a recent glycolysis-enhancing function for NEAT1_1, contributing to cancer cell proliferation and the Warburg effect, has been demonstrated. Previous studies have mainly focused on quantifying total NEAT1 and NEAT1_2 expression levels. However, in light of the NEAT1_1 role in cancer cell metabolism, the contribution from specific NEAT1 isoforms is no longer clear. Here, the roles of NEAT1_1 and NEAT1_2 in metabolism and cancer progression are discussed.
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Zhang H, Jin M, Ye M, Bei Y, Yang S, Liu K. The prognostic effect of PNN in digestive tract cancers and its correlation with the tumor immune landscape in colon adenocarcinoma. J Clin Lab Anal 2022; 36:e24327. [PMID: 35257416 PMCID: PMC8993647 DOI: 10.1002/jcla.24327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/09/2022] [Accepted: 02/18/2022] [Indexed: 01/21/2023] Open
Abstract
Background The present study investigated the expression, mutation, and methylation profile of PNN and its prognostic value in digestive tract cancers. The disparities in signaling pathways and the immune landscape in colon adenocarcinoma (COAD) based on PNN expression were specifically explored. Methods The expression, mutation, methylation levels of PNN, and survival data in esophageal cancer, gastric adenocarcinoma, COAD, and rectal adenocarcinoma were evaluated using several bioinformatic databases. Gene Ontology (GO) enrichment analysis and gene set enrichment analysis (GSEA) were performed to investigate the enriched biological functions and pathways in COAD. Several acknowledged bioinformatic algorithms were employed to assess the correlation between PNN expression and the tumor immune landscape in COAD. Results PNN was upregulated and remarkably related to tumor stage in digestive tract cancers. High expression of PNN was positively associated with poor progression‐free survival and overall survival time, specifically in COAD. PNN expression was identified as an independent prognostic factor in COAD. GO and GSEA analyses revealed that PNN participates in multiple biological processes underlying carcinogenicity in COAD. Further investigation showed that PNN expression was significantly associated with tumor‐infiltrating immune cells, immune cell functions, and several immune checkpoints in COAD. The PNN low expression group had a lower tumor immune dysfunction and exclusion (TIDE) score and a higher immunophenoscore (IPS), indicating a better response to immunotherapy. Conclusion PNN was highly expressed in digestive tract cancers and could act as an independent prognostic factor and a response predictor for immunotherapy in COAD.
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Affiliation(s)
- Hui Zhang
- Department of Radiation Oncology, The Lihuili Hospital, Ningbo Medical Center, Ningbo, China
| | - Ming Jin
- Department of Radiation Oncology, The Lihuili Hospital, Ningbo Medical Center, Ningbo, China
| | - Meng Ye
- Department of Oncology and Hematology, The Affiliated Hospital of Medical School of Ningbo University, Ningbo, China
| | - Yanping Bei
- Department of Radiation Oncology, The Lihuili Hospital, Ningbo Medical Center, Ningbo, China
| | - Shaohui Yang
- Department of General Surgery, The Lihuili Hospital, Ningbo Medical Center, Ningbo, China
| | - Kaitai Liu
- Department of Radiation Oncology, The Lihuili Hospital, Ningbo Medical Center, Ningbo, China
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Pinin Induces Epithelial-to-Mesenchymal Transition in Hepatocellular Carcinoma by Regulating m6A Modification. JOURNAL OF ONCOLOGY 2021; 2021:7529164. [PMID: 34917148 PMCID: PMC8670902 DOI: 10.1155/2021/7529164] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/20/2021] [Indexed: 12/12/2022]
Abstract
Pinin is a moonlighting protein localized in desmosomes and nucleus. It could promote the growth of hepatocellular carcinoma. Whether this protein can induce epithelial-to-mesenchymal transition (EMT) and malignant progression in HCC is unknown. This work found that Pinin prompts EMT in vitro and in vivo. Further mechanism study found that Pinin increases the level of N6-methyladenosine (m6A) modification of RNA by interacting with METTL3, which in turn induces snail1 expression. These findings suggest that Pinin induces EMT by regulating m6A modification and, thus, could be a potential anticancer target for HCC therapy.
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8
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Park MK, Zhang L, Min KW, Cho JH, Yeh CC, Moon H, Hormaechea-Agulla D, Mun H, Ko S, Lee JW, Jathar S, Smith AS, Yao Y, Giang NT, Vu HH, Yan VC, Bridges MC, Kourtidis A, Muller F, Chang JH, Song SJ, Nakagawa S, Hirose T, Yoon JH, Song MS. NEAT1 is essential for metabolic changes that promote breast cancer growth and metastasis. Cell Metab 2021; 33:2380-2397.e9. [PMID: 34879239 PMCID: PMC8813003 DOI: 10.1016/j.cmet.2021.11.011] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 08/27/2021] [Accepted: 11/16/2021] [Indexed: 01/08/2023]
Abstract
Accelerated glycolysis is the main metabolic change observed in cancer, but the underlying molecular mechanisms and their role in cancer progression remain poorly understood. Here, we show that the deletion of the long noncoding RNA (lncRNA) Neat1 in MMTV-PyVT mice profoundly impairs tumor initiation, growth, and metastasis, specifically switching off the penultimate step of glycolysis. Mechanistically, NEAT1 directly binds and forms a scaffold bridge for the assembly of PGK1/PGAM1/ENO1 complexes and thereby promotes substrate channeling for high and efficient glycolysis. Notably, NEAT1 is upregulated in cancer patients and correlates with high levels of these complexes, and genetic and pharmacological blockade of penultimate glycolysis ablates NEAT1-dependent tumorigenesis. Finally, we demonstrate that Pinin mediates glucose-stimulated nuclear export of NEAT1, through which it exerts isoform-specific and paraspeckle-independent functions. These findings establish a direct role for NEAT1 in regulating tumor metabolism, provide new insights into the Warburg effect, and identify potential targets for therapy.
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Affiliation(s)
- Mi Kyung Park
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Li Zhang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kyung-Won Min
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA; Department of Biology, College of Natural Sciences, Gangneung-Wonju National University, Gangneung-si, Gangwon-do 25457, Republic of Korea
| | - Jung-Hyun Cho
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Chih-Chen Yeh
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hyesu Moon
- Soonchunhyang Institute of Medi-bio Science, Soonchunhyang University, Cheonan-si, Chungcheongnam-do 31151, Republic of Korea
| | - Daniel Hormaechea-Agulla
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hyejin Mun
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Seungbeom Ko
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Ji Won Lee
- Department of Biology, College of Natural Sciences, Gangneung-Wonju National University, Gangneung-si, Gangwon-do 25457, Republic of Korea
| | - Sonali Jathar
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA; Laboratory of lncRNA Biology, National Center for Cell Science, Pune, Maharashtra 411007, India
| | - Aubrey S Smith
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Yixin Yao
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Nguyen Thu Giang
- Department of Biology Education, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Hong Ha Vu
- Department of Biology Education, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Victoria C Yan
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mary C Bridges
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Antonis Kourtidis
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Florian Muller
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jeong Ho Chang
- Department of Biology Education, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Su Jung Song
- Soonchunhyang Institute of Medi-bio Science, Soonchunhyang University, Cheonan-si, Chungcheongnam-do 31151, Republic of Korea
| | - Shinichi Nakagawa
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido 060-0812, Japan
| | - Tetsuro Hirose
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Je-Hyun Yoon
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA.
| | - Min Sup Song
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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The role and regulation of Pnn in proliferative and non-dividing cells: Form embryogenesis to pathogenesis. Biochem Pharmacol 2021; 192:114672. [PMID: 34237338 DOI: 10.1016/j.bcp.2021.114672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 11/20/2022]
Abstract
Pnn, a multiple functional protein, plays roles in embryonic development, cellular differentiation, tumorigenesis, and metastasis. In the past two decades, the functions of Pnn in regulating RNA alternative splicing, gene regulation, and cell-cell connection have been revealed. Although Pnn is originally identified as a desmosome-associated protein for linking desmosome and intermediated filament, emerging evidence implies that Pnn not only is a desmosome protein but also plays critical roles in the nucleus. To date, through cell biology investigation and the generation of animal models with genetic manipulation, the physiological role of Pnn has been characterized in the research fields of developmental biology, tumor biology, and neuroscience. Through proteomic and molecular biology studies, transcription regulators, splicing regulators, and cytoskeletal proteins were found to interact with Pnn. In addition, histopathological and biochemical evidence has pointed to an association of Pnn expression level with tumorigenesis and metastasis. A previous clinical study also demonstrated a correlation between a reduced expression of Pnn and human dementia. Besides, experimental studies showed a protective role of Pnn against ischemic stress in astrocytes. All indicated a variety of roles of Pnn in different cell types. In this review article, we introduced the role of Pnn in embryogenesis and pathogenesis as well as discussed its potential clinical application.
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Li Z, Jin Y, Zou Q, Shi X, Wu Q, Lin Z, He Q, Huang G, Qi S. Integrated genomic and transcriptomic analysis suggests KRT18 mutation and MTAP are key genetic alterations related to the prognosis between astrocytoma and glioblastoma. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:713. [PMID: 33987411 PMCID: PMC8106028 DOI: 10.21037/atm-21-1317] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Background Astrocytoma and glioblastoma (GBM) are the two main subtypes of glioma, with the 2016 World Health Organization Classification of Tumors of the Central Nervous System (CNS WHO) classifying them into different grades. GBM is the most malignant among all CNS tumors with a 5-year survival rate of less than 5%. Although the prognosis of patients with astrocytoma is better than that of GBM in general, patients with anaplastic astrocytoma (AA) and isocitrate dehydrogenase (IDH) wild type have a similar prognosis as GBM and entail a high risk of progression. Exploring the molecular driving force behind the malignant phenotype of astrocytoma and GBM will help explain the diversity of glioma and discover new drug targets. Methods We enrolled 12 patients with astrocytoma and 12 patients with GBM and performed whole-exome sequencing (WES) and RNA sequencing analysis on tumor samples from the patients. Results We found that the somatic mutation of KRT18, which is associated with cell apoptosis and adhesion by interacting with receptor 1-associated protein (TRADD) and pinin, was significantly enriched in astrocytoma, but rare in GBM. Copy number loss of MTAP, which is closely related to a poor prognosis of glioma, was found to be significantly enriched in GBM. In addition, different somatic copy number alteration (SCNA), gene expression, and immune cell infiltration patterns between astrocytoma and GBM were found. Conclusions This study revealed the distinct characteristics of astrocytoma and GBM at the DNA and RNA level. Somatic mutation of KRT18 and copy number loss of MTAP, two key genetic alterative genes in astrocytoma and GBM, have the potential to become therapeutic targets in glioma.
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Affiliation(s)
- Zhiyong Li
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yinghui Jin
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qingping Zou
- GenomiCare Biotechnology (Shanghai) Co., Ltd., Shanghai, China
| | - Xiaofeng Shi
- Department of Neurosurgery, Longgang Central Hospital of Shenzhen, Shenzhen, China
| | - Qianchao Wu
- GenomiCare Biotechnology (Shanghai) Co., Ltd., Shanghai, China
| | - Zhiying Lin
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qun He
- GenomiCare Biotechnology (Shanghai) Co., Ltd., Shanghai, China
| | - Guanglong Huang
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Songtao Qi
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
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11
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Qin G, Wu X. Hsa_circ_0032463 acts as the tumor promoter in osteosarcoma by regulating the miR‑330‑3p/PNN axis. Int J Mol Med 2021; 47:92. [PMID: 33786605 PMCID: PMC8012025 DOI: 10.3892/ijmm.2021.4925] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/25/2021] [Indexed: 12/20/2022] Open
Abstract
Osteosarcoma (OS), also known as bone cancer, is a threat to the lives of millions of adolescents worldwide. Although dedicated efforts have been invested in reducing the mortality rate of this bone cancer, the research community is yet to find the exact causes of OS. Thus, the present research aimed to study the association between circular RNA circ_0032463 and OS progression. The impact of circ_0032463 on cells with OS was first evaluated using reverse transcription-quantitative PCR. This evaluation was followed by the assessment of cell proliferation, viability, apoptosis, invasion and adhesion using BrdU, Cell Counting Kit-8, flow cytometry, Transwell and cell adhesion assays, respectively. RNA pull-down, RNA immunoprecipitation chip and dual-luciferase reporter systems were utilized to investigate the relationship between circ_0032463, microRNA (miR)-330-3p and Pinin desmosome associated protein (PNN) in OS. The findings indicated that circ_0032463 and PNN were highly expressed in OS tissues and OS cell lines, and that they facilitated cell proliferation, viability, invasion and adhesion, but attenuated cell apoptosis in OS cells. The low expression of miR-330-3p suppressed OS development. It was also noted that circ_0032463 inhibited miR-330-3p to upregulate PNN expression. In conclusion, this study confirmed that by regulating the miR-330-3p/PNN axis, circular RNA circ_0032463 could function as a tumor enhancer in cells with OS.
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Affiliation(s)
- Guanghua Qin
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Xuejian Wu
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
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Reticular Basement Membrane Thickness Is Associated with Growth- and Fibrosis-Promoting Airway Transcriptome Profile-Study in Asthma Patients. Int J Mol Sci 2021; 22:ijms22030998. [PMID: 33498209 PMCID: PMC7863966 DOI: 10.3390/ijms22030998] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/15/2021] [Accepted: 01/17/2021] [Indexed: 12/24/2022] Open
Abstract
Airway remodeling in asthma is characterized by reticular basement membrane (RBM) thickening, likely related to epithelial structural and functional changes. Gene expression profiling of the airway epithelium might identify genes involved in bronchial structural alterations. We analyzed bronchial wall geometry (computed tomography (CT)), RBM thickness (histology), and the bronchial epithelium transcriptome profile (gene expression array) in moderate to severe persistent (n = 21) vs. no persistent (n = 19) airflow limitation asthmatics. RBM thickness was similar in the two studied subgroups. Among the genes associated with increased RBM thickness, the most essential were those engaged in cell activation, proliferation, and growth (e.g., CDK20, TACC2, ORC5, and NEK5) and inhibiting apoptosis (e.g., higher mRNA expression of RFN34, BIRC3, NAA16, and lower of RNF13, MRPL37, CACNA1G). Additionally, RBM thickness correlated with the expression of genes encoding extracellular matrix (ECM) components (LAMA3, USH2A), involved in ECM remodeling (LTBP1), neovascularization (FGD5, HPRT1), nerve functioning (TPH1, PCDHGC4), oxidative stress adaptation (RIT1, HSP90AB1), epigenetic modifications (OLMALINC, DNMT3A), and the innate immune response (STAP1, OAS2). Cluster analysis revealed that genes linked with RBM thickness were also related to thicker bronchial walls in CT. Our study suggests that the pro-fibrotic profile in the airway epithelial cell transcriptome is associated with a thicker RBM, and thus, may contribute to asthma airway remodeling.
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13
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Tang T, Yang L, Cao Y, Wang M, Zhang S, Gong Z, Xiong F, He Y, Zhou Y, Liao Q, Xiang B, Zhou M, Guo C, Li X, Li Y, Xiong W, Li G, Zeng Z. LncRNA AATBC regulates Pinin to promote metastasis in nasopharyngeal carcinoma. Mol Oncol 2020; 14:2251-2270. [PMID: 32364663 PMCID: PMC7463349 DOI: 10.1002/1878-0261.12703] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/23/2019] [Accepted: 04/29/2020] [Indexed: 12/17/2022] Open
Abstract
Long noncoding RNA (lncRNA) have emerged as crucial regulators for a myriad of biological processes, and perturbations in their cellular expression levels have often been associated with cancer pathogenesis. In this study, we identified AATBC (apoptosis‐associated transcript in bladder cancer, LOC284837) as a novel lncRNA. AATBC was found to be highly expressed in nasopharyngeal carcinoma (NPC), and increased AATBC expression was associated with poor survival in patients with NPC. Furthermore, AATBC promoted migration and invasion of NPC cells in vitro, as well as metastasis in vivo. AATBC upregulated the expression of the desmosome‐associated protein pinin (PNN) through miR‐1237‐3p sponging. In turn, PNN interacted with the epithelial–mesenchymal transition (EMT) activator ZEB1 and upregulated ZEB1 expression to promote EMT in NPC cells. Collectively, our results indicate that AATBC promotes NPC progression through the miR‐1237‐3p–PNN–ZEB1 axis. Our findings indicate AATBC as a potential prognostic biomarker or therapeutic target in NPC.
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Affiliation(s)
- Ting Tang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Liting Yang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China.,Department of Stomatology, Xiangya Hospital, Central South University, Changsha, China
| | - Yujian Cao
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Maonan Wang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Shanshan Zhang
- Department of Stomatology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhaojian Gong
- Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Fang Xiong
- Department of Stomatology, Xiangya Hospital, Central South University, Changsha, China
| | - Yi He
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Yujuan Zhou
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Qianjin Liao
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Bo Xiang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Ming Zhou
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Can Guo
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Xiaoling Li
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Yong Li
- Department of Medicine, Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Wei Xiong
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Guiyuan Li
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
| | - Zhaoyang Zeng
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, China
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14
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Dickherber ML, Garnett-Benson C. NAD-linked mechanisms of gene de-repression and a novel role for CtBP in persistent adenovirus infection of lymphocytes. Virol J 2019; 16:161. [PMID: 31864392 PMCID: PMC6925507 DOI: 10.1186/s12985-019-1265-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 12/03/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Adenovirus (AdV) infection is ubiquitous in the human population and causes acute infection in the respiratory and gastrointestinal tracts. In addition to lytic infections in epithelial cells, AdV can persist in a latent form in mucosal lymphocytes, and nearly 80% of children contain viral DNA in the lymphocytes of their tonsils and adenoids. Reactivation of latent AdV is thought to be the source of deadly viremia in pediatric transplant patients. Adenovirus latency and reactivation in lymphocytes is not well studied, though immune cell activation has been reported to promote productive infection from latency. Lymphocyte activation induces global changes in cellular gene expression along with robust changes in metabolic state. The ratio of free cytosolic NAD+/NADH can impact gene expression via modulation of transcriptional repressor complexes. The NAD-dependent transcriptional co-repressor C-terminal Binding Protein (CtBP) was discovered 25 years ago due to its high affinity binding to AdV E1A proteins, however, the role of this interaction in the viral life cycle remains unclear. METHODS The dynamics of persistently- and lytically-infected cells are evaluated. RT-qPCR is used to evaluate AdV gene expression following lymphocyte activation, treatment with nicotinamide, or disruption of CtBP-E1A binding. RESULTS PMA and ionomycin stimulation shifts the NAD+/NADH ratio in lymphocytic cell lines and upregulates viral gene expression. Direct modulation of NAD+/NADH by nicotinamide treatment also upregulates early and late viral transcripts in persistently-infected cells. We found differential expression of the NAD-dependent CtBP protein homologs between lymphocytes and epithelial cells, and inhibition of CtBP complexes upregulates AdV E1A expression in T lymphocyte cell lines but not in lytically-infected epithelial cells. CONCLUSIONS Our data provide novel insight into factors that can regulate AdV infections in activated human lymphocytes and reveal that modulation of cellular NAD+/NADH can de-repress adenovirus gene expression in persistently-infected lymphocytes. In contrast, disrupting the NAD-dependent CtBP repressor complex interaction with PxDLS-containing binding partners paradoxically alters AdV gene expression. Our findings also indicate that CtBP activities on viral gene expression may be distinct from those occurring upon metabolic alterations in cellular NAD+/NADH ratios or those occurring after lymphocyte activation.
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Affiliation(s)
- Megan L Dickherber
- Charlie Garnett-Benson, Department of Biology, Georgia State University, 161 Jesse Hill Jr. Dr, Atlanta, GA, 30303, USA
| | - Charlie Garnett-Benson
- Charlie Garnett-Benson, Department of Biology, Georgia State University, 161 Jesse Hill Jr. Dr, Atlanta, GA, 30303, USA.
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15
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Kang GJ, Park MK, Byun HJ, Kim HJ, Kim EJ, Yu L, Kim B, Shim JG, Lee H, Lee CH. SARNP, a participant in mRNA splicing and export, negatively regulates E-cadherin expression via interaction with pinin. J Cell Physiol 2019; 235:1543-1555. [PMID: 31313837 DOI: 10.1002/jcp.29073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/18/2019] [Indexed: 12/17/2022]
Abstract
Triple-negative breast cancer (TNBC) is associated with a high mortality rate, which is related to the insufficient number of appropriate biomarkers and targets. Therefore, there is an urgent need to discover appropriate biomarkers and targets for TNBC. SARNP (Hcc-1 and CIP29) is highly expressed in several cancers. It binds to UAP56, an RNA helicase component of the TREX complex in messenger RNA (mRNA) splicing and export. However, the role of SARNP in mRNA splicing and export and in the progression of breast cancer, especially of TNBC, remains unknown. Therefore, we examined the role of SARNP in mRNA splicing and export and progression of TNBC. We confirmed that SARNP binds to UAP56 and Aly and that SARNP overexpression enhances mRNA splicing, whereas its knockdown suppressed mRNA export. The SARNP overexpression induced the proliferation of MCF7 cells, whereas its knockdown induced E-cadherin expression and downregulated vimentin and N-cadherin expressions in SK-BR-3 and MDA-MB-231 cells. SARNP downregulates E-cadherin expression by interaction with pinin. Mice injected with MDA-MB-231shSARNP cells exhibited a significant reduction in tumor growth and lung metastasis compared with those injected with MDA-MB-231shCon cells in vivo. These findings suggested that SARNP is involved in mRNA splicing and export. SARNP maintains mesenchymal phenotype by escaping from inhibitory interaction with pinin leading to the downregulation of E-cadherin expression.
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Affiliation(s)
| | - Mi Kyung Park
- Division of Cancer Biology, National Cancer Center, Goyang, Korea
| | | | - Hyun Ji Kim
- College of Pharmacy, Dongguk University, Seoul, Korea
| | - Eun Ji Kim
- College of Pharmacy, Dongguk University, Seoul, Korea
| | - Lu Yu
- College of Pharmacy, Dongguk University, Seoul, Korea
| | - Boram Kim
- College of Pharmacy, Dongguk University, Seoul, Korea
| | - Jae Gal Shim
- Division of Cancer Biology, National Cancer Center, Goyang, Korea
| | - Ho Lee
- Division of Cancer Biology, National Cancer Center, Goyang, Korea
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16
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Mukda S, Tsai CY, Leu S, Yang JL, Chan SHH. Pinin protects astrocytes from cell death after acute ischemic stroke via maintenance of mitochondrial anti-apoptotic and bioenergetics functions. J Biomed Sci 2019; 26:43. [PMID: 31167655 PMCID: PMC6549339 DOI: 10.1186/s12929-019-0538-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 05/26/2019] [Indexed: 11/27/2022] Open
Abstract
Background Stroke is the second most common cause of deaths worldwide. After an ischemic stroke, the proliferated reactive astrocytes in the peri-infarct areas play a beneficial role in neuronal survival. As such, astrocytes have gradually become a target for neuroprotection in stroke. The present study assessed the hypothesis that Pinin (Pnn), originally identified as a nuclear and desmosome-associated protein and is now known to possess anti-apoptotic capacity, protects astrocytes from cell death after ischemic stroke and delineated the underlying mechanisms. Methods In in vivo experiments, adult male Sprague-Dawley rats (12-week old) were used to induce acute focal cerebral ischemia employing the middle cerebral artery occlusion (MCAO) method. In in vitro experiments, postnatal day 1 (P1) Sprague-Dawley rat pups were used to prepare cultures of primary astrocytes. Oxygen-glucose deprivation (OGD) and re-oxygenation (OGD/R) procedures were employed to mimic the hypoxic-ischemic condition of stroke in those astrocytes. Results We found in the peri-infarct area of the ipsilateral cortex and striatum in Sprague-Dawley rats after transient MCAO an increase in Pnn expression that correlated positively with the time-course of infarction as detected by T2-weighted imaging and triphenyltetrazolium chloride staining, augmented number of reactive astrocytes that double-labelled with Pnn as determined by immunofluorescence, and enhanced cytotoxic edema as revealed by diffusion weighted imaging; but mirrored the decreased cleaved caspase-3 as measured by western blot. In an OGD and OGD/R model using primary cultured astrocytes, treatment with Pnn siRNA doubled the chance of surviving astrocytes to manifest cell death as revealed by flow cytometry, and blunted activated ERK signaling, reduced Bcl-2 expression and augmented cleaved caspase 3 detected by western blot in the normoxia, OGD or OGD/R group. Gene-knockdown of Pnn also impeded the reversal from decline in cell viability, elevation in lactate dehydrogenase leakage and decrease in ATP production in the OGD/R group. Conclusion We conclude that the endogenous Pnn participates in neuroprotection after acute ischemic stroke by preserving the viability of astrocytes that survived the ischemic challenge via maintenance of mitochondrial anti-apoptotic and bioenergetics functions. Electronic supplementary material The online version of this article (10.1186/s12929-019-0538-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sujira Mukda
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, 25/25 Phuttamonthon 4 Road, Salaya, Nakhon Pathom, 73170, Thailand.,Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung, 83301, Taiwan
| | - Ching-Yi Tsai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung, 83301, Taiwan
| | - Steve Leu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung, 83301, Taiwan
| | - Jenq-Lin Yang
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung, 83301, Taiwan
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung, 83301, Taiwan.
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17
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Yang X, Sun D, Dong C, Tian Y, Gao Z, Wang L. Pinin associates with prognosis of hepatocellular carcinoma through promoting cell proliferation and suppressing glucose deprivation-induced apoptosis. Oncotarget 2018; 7:39694-39704. [PMID: 27175589 PMCID: PMC5129963 DOI: 10.18632/oncotarget.9233] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/24/2016] [Indexed: 01/16/2023] Open
Abstract
The roles of Pinin have been well studied in epithelial cell-cell adhesion and RNA alternative splicing, which suggests its involvement in cancer progression. However, little is known about the association between Pinin expression and hepatocellular carcinoma (HCC) tumorigenesis. In this study we report increased expression of Pinin in HCC tissues and cells. Elevated levels of Pinin closely associates with pathological grade and overall survival of patients with hepatocellular carcinoma. Suppression of Pinin expression via lentivirus mediated shRNA knockdown inhibits HCC cell proliferation, colony formation, cell viability, but promotes glucose deprivation (GD)-induced cell apoptosis. On the contrary, overexpression of Pinin reverses these effects observed in Pinin depleted cells. Meanwhile, overexpression of Pinin attenuates GD initiated poly ADP-ribose polymerase (PARP) cleavage and ERK1/2 dephosphorylation, which can be completely blocked with MEK1/2 inhibitor U0126. Therefore, we conclude that Pinin contributes to HCC progression and resistance to GD-induced apoptosis via maintaining ERK1/2 activation and hence may be a potential therapeutic target in hepatocellular carcinoma treatment.
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Affiliation(s)
- Xuejun Yang
- Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian 116027, China.,Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Deguang Sun
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Chengyong Dong
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Yu Tian
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Zhenming Gao
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Liming Wang
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116011, China
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18
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Wei Z, Ma W, Qi X, Zhu X, Wang Y, Xu Z, Luo J, Wang D, Guo W, Li X, Xin S, Yu J, Li G. Pinin facilitated proliferation and metastasis of colorectal cancer through activating EGFR/ERK signaling pathway. Oncotarget 2017; 7:29429-39. [PMID: 27107420 PMCID: PMC5045407 DOI: 10.18632/oncotarget.8738] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 03/28/2016] [Indexed: 12/29/2022] Open
Abstract
Increasing emphasis has been put on the influence of desmosome related proteins on progress of colorectal cancer (CRC). Pinin (PNN) is a desmosome-associated molecule that has been reported its overexpression could increase desmoglein 2 (DSG2) and E-cadherin (E-ca) levels. However, it was documented that DSG2 and E-ca had opposite functions in CRC. Thus, we attempted to elucidate function and mechanism of PNN in CRC. Herein, we revealed that overexpression of PNN was significantly correlated with the aggressive characteristics and indicated poor overall survival of CRC patients. In addition, the proliferation, invasion in vitro, and tumorigenic growth, metastasis in vivo were also promoted by the up-regulation of PNN. It was also verified that up-regulation of PNN increased the expression of DSG2 and activated the EGFR/ERK signaling pathway. Our findings suggested that PNN, as a valuable marker of prognosis, has important influence on the progression of CRC.
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Affiliation(s)
- Zhigang Wei
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Wenhui Ma
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaolong Qi
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xianjun Zhu
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yutian Wang
- Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhuoluo Xu
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jun Luo
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Da Wang
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Weihong Guo
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaomei Li
- Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Sainan Xin
- Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jiang Yu
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.,Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Guoxin Li
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
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19
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Zhang Y, Kwok JSL, Choi PW, Liu M, Yang J, Singh M, Ng SK, Welch WR, Muto MG, Tsui SK, Sugrue SP, Berkowitz RS, Ng SW. Pinin interacts with C-terminal binding proteins for RNA alternative splicing and epithelial cell identity of human ovarian cancer cells. Oncotarget 2017; 7:11397-411. [PMID: 26871283 PMCID: PMC4905481 DOI: 10.18632/oncotarget.7242] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 01/24/2016] [Indexed: 11/25/2022] Open
Abstract
Unlike many other human solid tumors, ovarian tumors express many epithelial markers at a high level for cell growth and local invasion. The phosphoprotein Pinin plays a key role in epithelial cell identity. We showed that clinical ovarian tumors and ovarian cancer cell lines express a high level of Pinin when compared with normal ovarian tissues and immortalized normal ovarian surface epithelial cell lines. Pinin co-localized and physically interacted with transcriptional corepressor C-terminal binding proteins, CtBP1 and CtBP2, in the nuclei of cancer cells. Knockdown of Pinin in ovarian cancer cells resulted in specific reduction of CtBP1 protein expression, cell adhesion, anchorage-independent growth, and increased drug sensitivity. Whole transcriptomic comparison of next-generation RNA sequencing data between control ovarian cancer cell lines and cancer cell lines with respective knockdown of Pinin, CtBP1, and CtBP2 expression also showed reduced expression of CtBP1 mRNA in the Pinin knockdown cell lines. The Pinin knockdown cell lines shared significant overlap of differentially expressed genes and RNA splicing aberrations with CtBP1 knockdown and in a lesser degree with CtBP2 knockdown cancer cells. Hence, Pinin and CtBP are oncotargets that closely interact with each other to regulate transcription and pre-mRNA alternative splicing and promote cell adhesion and other epithelial characteristics of ovarian cancer cells.
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Affiliation(s)
- Yanli Zhang
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Jamie Sui-Lam Kwok
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Pui-Wah Choi
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Minghua Liu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Junzheng Yang
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Margit Singh
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Shu-Kay Ng
- School of Medicine and Menzies Health Institute Queensland, Griffith University, Meadowbrook, Australia
| | - William R Welch
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael G Muto
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Stephen Kw Tsui
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Stephen P Sugrue
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ross S Berkowitz
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
| | - Shu-Wing Ng
- Laboratory of Gynecologic Oncology, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA
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20
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Chung DD, Frausto RF, Lin BR, Hanser EM, Cohen Z, Aldave AJ. Transcriptomic Profiling of Posterior Polymorphous Corneal Dystrophy. Invest Ophthalmol Vis Sci 2017; 58:3202-3214. [PMID: 28654985 PMCID: PMC5488878 DOI: 10.1167/iovs.17-21423] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose To investigate the molecular basis of posterior polymorphous corneal dystrophy (PPCD) by examining the PPCD transcriptome and the effect of decreased ZEB1 expression on corneal endothelial cell (CEnC) gene expression. Methods Next-generation RNA sequencing (RNA-seq) analyses of corneal endothelium from two PPCD-affected individuals (one with PPCD3 and one of unknown genetic cause) compared with two age-matched controls, and primary human CEnC (pHCEnC) transfected with siRNA-mediated ZEB1 knockdown. The expression of selected differentially expressed genes was validated by quantitative polymerase chain reaction (qPCR) and/or assessed by in situ hybridization in the corneal endothelium of four independent cases of PPCD (one with PPCD3 and three of unknown genetic cause). Results Expression of 16% and 46% of the 104 protein-coding genes specific to ex vivo corneal endothelium was lost in the endothelium of two individuals with PPCD. Thirty-two genes associated with ZEB1 and 3 genes (BMP4, CCND1, ZEB1) associated with OVOL2 were differentially expressed in the same direction in both individuals with PPCD. Immunohistochemistry staining and RNA-seq analyses demonstrated variable expression of type IV collagens in PPCD corneas. Decreasing ZEB1 expression in pHCEnC altered expression of 711 protein-coding genes, many of which are associated with canonical pathways regulating various cellular processes. Conclusions Identification of the altered transcriptome in PPCD and in a cell-based model of PPCD provided insight into the molecular alterations characterizing PPCD. Further study of the differentially expressed genes associated with ZEB1 and OVOL2 is expected to identify candidate genes for individuals with PPCD and without a ZEB1 or OVOL2 mutation.
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Affiliation(s)
- Doug D Chung
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
| | - Ricardo F Frausto
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
| | - Benjamin R Lin
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
| | - Evelyn M Hanser
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
| | - Zack Cohen
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
| | - Anthony J Aldave
- Stein Eye Institute, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, United States
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21
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Kim YD, Lee J, Kim HS, Lee MO, Son MY, Yoo CH, Choi JK, Lee SC, Cho YS. The unique spliceosome signature of human pluripotent stem cells is mediated by SNRPA1, SNRPD1, and PNN. Stem Cell Res 2017; 22:43-53. [PMID: 28595116 DOI: 10.1016/j.scr.2017.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/25/2017] [Accepted: 05/26/2017] [Indexed: 12/21/2022] Open
Abstract
Spliceosomes are the core host of pre-mRNA splicing, allowing multiple protein isoforms to be produced from a single gene. Herein, we reveal that spliceosomes are more abundant in human pluripotent stem cells (hPSs), including human embryonic stem cells (hESs) and human induced pluripotent stem cells (hiPSs), than non-hPSs, and their presence is associated with high transcriptional activity. Supportively, spliceosomal components involved in the catalytically active pre-mRNA splicing step were mainly co-localized with hPS spliceosomes. By profiling the gene expression of 342 selected splicing factors, we found that 71 genes were significantly altered during the reprogramming of human somatic cells into hiPSs. Among them, SNRPA1, SNRPD1, and PNN were significantly up-regulated during the early stage of reprogramming, identified as hub genes by interaction network and cluster analysis. SNRPA1, SNRPD1, or PNN depletion led to a pronounced loss of pluripotency and significantly blocked hiPS generation. SNRPA1, SNRPD1, and PNN co-localized with the hPS spliceosomes, physically interacted with each other, and positively influenced the appearance of hPS spliceosomes. Our data suggest that SNRPA1, SNRPD1, and PNN are key players in the regulation of pluripotency-specific spliceosome assembly and the acquisition and maintenance of pluripotency.
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Affiliation(s)
- Young-Dae Kim
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Jungwoon Lee
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Han-Seop Kim
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Mi-Ok Lee
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Mi-Young Son
- Stem Cell Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Chae Hwa Yoo
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Jung-Kyun Choi
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea; Department of Bioscience, KRIBB School, University of Science & Technology, 113 Gwahak-ro, Yuseong-gu, Daejeon 34113, Republic of Korea
| | - Sang Chul Lee
- Research Center for Metabolic Regulation, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Yee Sook Cho
- Stem Cell Research Laboratory, Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea; Department of Bioscience, KRIBB School, University of Science & Technology, 113 Gwahak-ro, Yuseong-gu, Daejeon 34113, Republic of Korea.
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Ray SK, Li HJ, Leiter AB. Oligomeric form of C-terminal-binding protein coactivates NeuroD1-mediated transcription. FEBS Lett 2016; 591:205-212. [PMID: 27880001 DOI: 10.1002/1873-3468.12501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 11/01/2016] [Accepted: 11/07/2016] [Indexed: 12/12/2022]
Abstract
The mechanism underlying transcriptional coactivation by the corepressor C-terminal-binding protein (CtBP) is not established. We previously found that CtBP co-occupies several actively transcribed endocrine genes with the transcription factor NeuroD1 to paradoxically increase transcription by recruiting KDM1A and CoREST. While the importance of the oligomeric form of CtBP for corepression is well established, the role of oligomerization in transcriptional coactivation has received little attention. Here, we examined the importance of the oligomeric state of CtBP for coactivation of NeuroD1-dependent transcription by expressing a CtBP dimerization mutant in cells depleted of endogenous CtBP. Dimerization mutants failed to increase transcription or to associate with KDM1A and CoREST, suggesting that oligomeric, but not monomeric CtBP is required to recruit other proteins needed to activate transcription.
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Affiliation(s)
- Subir K Ray
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Hui J Li
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Andrew B Leiter
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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Wang F, Soprano KJ, Soprano DR. Role of Acinus in regulating retinoic acid-responsive gene pre-mRNA splicing. J Cell Physiol 2015; 230:791-801. [PMID: 25205379 DOI: 10.1002/jcp.24804] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 09/05/2014] [Indexed: 02/03/2023]
Abstract
Acinus-S' is a corepressor for retinoic acid receptor (RAR)-dependent gene transcription and has been suggested to be involved in RNA processing. In this study, the role of Acinus isoforms in regulating pre-mRNA splicing was explored using in vivo splicing assays. Both Acinus-L and Acinus-S', with the activity of Acinus-L higher than that of Acinus-S', increase the splicing of a retinoic acid (RA)-responsive minigene containing a weak 5' splice site but not a RA-responsive minigene containing a strong 5' splice site. RA treatment further enhances the splicing of the weak 5' splice site by Acinus in a dose- and time-dependent manner, suggesting a RA-dependent activity in addition to a RA-independent activity of Acinus. The RA-independent effect of Acinus occurs to varying degrees using minigene constructs containing several different promoters, while the RA-dependent splicing activity of Acinus is specific for transcripts derived from the minigene driven by a RA response element (RARE)-containing promoter. This suggests that the ligand-dependent splicing activity of Acinus is related to the RA-activated RAR bound to the RARE. The RRM domain is necessary for the RA-dependent splicing activity of Acinus and the RA-independent splicing activity of Acinus is repressed by RNPS1. Importantly, measurement of the splicing of endogenous human RARβ and Bcl-x in vivo demonstrates that Acinus stimulates the use of the weaker alternative 5' splice site of these two genes in a RA-dependent manner for RARβ and a RA-independent manner for Bcl-x. Taken together, these studies demonstrate that Acinus functions in both RAR-dependent splicing and RAR-dependent transcription.
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Affiliation(s)
- Fang Wang
- Department of Biochemistry, Temple University School of Medicine, Philadelphia, PA
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MCRIP1, an ERK Substrate, Mediates ERK-Induced Gene Silencing during Epithelial-Mesenchymal Transition by Regulating the Co-Repressor CtBP. Mol Cell 2015; 58:35-46. [DOI: 10.1016/j.molcel.2015.01.023] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 12/05/2014] [Accepted: 01/14/2015] [Indexed: 12/30/2022]
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Oxygen-dependent acetylation and dimerization of the corepressor CtBP2 in neural stem cells. Exp Cell Res 2015; 332:128-35. [DOI: 10.1016/j.yexcr.2014.10.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 10/15/2014] [Indexed: 11/21/2022]
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Wu W, Tan XF, Tan HT, Lim TK, Chung MCM. Unbiased proteomic and transcript analyses reveal that stathmin-1 silencing inhibits colorectal cancer metastasis and sensitizes to 5-fluorouracil treatment. Mol Cancer Res 2014; 12:1717-28. [PMID: 25063586 DOI: 10.1158/1541-7786.mcr-14-0088-t] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
UNLABELLED Colorectal cancer metastasis is a major cause of mortality worldwide, which may only be controlled with novel methods limiting tumor dissemination and chemoresistance. High stathmin-1 (STMN1) expression was previously established as a hallmark of colorectal cancer progression and predictor of poor survival; however, the mechanism of action is less clear. This work demonstrates that STMN1 silencing arrests tumor-disseminative cascades by inhibiting multiple metastatic drivers, and repressing oncogenic and mesenchymal transcription. Using a sensitive iTRAQ labeling proteomic approach that quantified differential abundance of 4562 proteins, targeting STMN1 expression was shown to reinstate the default cellular program of metastatic inhibition, and promote cellular adhesion via amplification of hemidesmosomal junctions and intermediate filament tethering. Silencing STMN1 also significantly improved chemoresponse to the classical colorectal cancer therapeutic agent, 5FU, via a novel caspase-6 (CASP6)-dependent mechanism. Interestingly, the prometastatic function of STMN1 was independent of p53 but required phosphorylations at S25 or S38; abrogating phosphorylative events may constitute an alternative route to achieving metastatic inhibition. These findings establish STMN1 as a potential target in antimetastatic therapy, and demonstrate the power of an approach coupling proteomics and transcript analyses in the global assessment of treatment benefits and potential side-effects. IMPLICATIONS Stathmin-1 is a potential candidate in colorectal cancer therapy that targets simultaneously the twin problems of metastatic spread and chemoresistance.
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Affiliation(s)
- Wei Wu
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Xing Fei Tan
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Hwee Tong Tan
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Teck Kwang Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Maxey Ching Ming Chung
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore.
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Joo JH, Ryu D, Peng Q, Sugrue SP. Role of Pnn in alternative splicing of a specific subset of lncRNAs of the corneal epithelium. Mol Vis 2014; 20:1629-42. [PMID: 25489234 PMCID: PMC4235046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 11/14/2014] [Indexed: 11/08/2022] Open
Abstract
PURPOSE GG-H whole transcriptome array analysis suggested involvement of PININ (PNN) in the alternative splicing of multiple long non-coding RNAs (lncRNAs). To further investigate PNN's role in regulating the alternative splicing of lncRNAs in a corneal epithelial context, we performed detailed analyses for detecting and identifying alternatively spliced lncRNAs. METHODS Total RNA was isolated from PNN knockdown human corneal epithelial (HCET) cells or Pnn-deficient mouse corneas, and subjected to real-time-PCR (RT-PCR) assays, and the alternatively spliced lncRNAs were counted. Alternatively spliced lncRNAs were detected with in situ hybridization with variant-specific RNA probes on human cornea sections. RESULTS Our analysis uncovered PNN's impact on the transcript levels of several lncRNAs including Linc00085 and HAS2-AS1. Interestingly, a mouse ortholog of HAS2-AS1, Has2as, clearly exhibited a differential splicing pattern among three major splice variants in the Pnn-deficient mouse cornea. The sequence analyses and quantification of splice variants of candidate lncRNAs, including RP11-295B20.2, RP11-18I14.1, and RP11-322M19.1, demonstrated complex configuration of their splicing changes, with a significant impact of PNN on the process. Knockdown of PNN in HCET cells led to specific changes in the inclusion of multiple cassette exons as well as in the use of alternative splice sites in RP11-322M19.1 and RP11-18I14.1, resulting in considerable net changes in the ratio between the splice variants. Finally, in situ hybridization analyses revealed the presence of RP11-295G20.2 in the nuclei of corneal epithelial cells, but not in the stromal cells of the human cornea, while RP11-322M19.1 was present in epithelial and non-epithelial cells. CONCLUSIONS The data suggest PNN's role in the alternative splicing of a specific subset of lncRNAs might have a significant impact on the corneal epithelium.
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Affiliation(s)
- Jeong Hoon Joo
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL
| | - Danny Ryu
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL
| | - Qian Peng
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL
| | - Stephen P Sugrue
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL
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C-Terminal Binding Protein: A Molecular Link between Metabolic Imbalance and Epigenetic Regulation in Breast Cancer. Int J Cell Biol 2013; 2013:647975. [PMID: 23762064 PMCID: PMC3671672 DOI: 10.1155/2013/647975] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 04/14/2013] [Accepted: 04/15/2013] [Indexed: 12/21/2022] Open
Abstract
The prevalence of obesity has given rise to significant global concerns as numerous population-based studies demonstrate an incontrovertible association between obesity and breast cancer. Mechanisms proposed to account for this linkage include exaggerated levels of carbohydrate substrates, elevated levels of circulating mitogenic hormones, and inflammatory cytokines that impinge on epithelial programming in many tissues. Moreover, recently many scientists have rediscovered the observation, first described by Otto Warburg nearly a century ago, that most cancer cells undergo a dramatic metabolic shift in energy utilization and expenditure that fuels and supports the cellular expansion associated with malignant proliferation. This shift in substrate oxidation comes at the cost of sharp changes in the levels of the high energy intermediate, nicotinamide adenine dinucleotide (NADH). In this review, we discuss a novel example of how shifts in the concentration and flux of substrates metabolized and generated during carbohydrate metabolism represent components of a signaling network that can influence epigenetic regulatory events in the nucleus. We refer to this regulatory process as "metabolic transduction" and describe how the C-terminal binding protein (CtBP) family of NADH-dependent nuclear regulators represents a primary example of how cellular metabolic status can influence epigenetic control of cellular function and fate.
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Padmanabhan MS, Ma S, Burch-Smith TM, Czymmek K, Huijser P, Dinesh-Kumar SP. Novel positive regulatory role for the SPL6 transcription factor in the N TIR-NB-LRR receptor-mediated plant innate immunity. PLoS Pathog 2013; 9:e1003235. [PMID: 23516366 PMCID: PMC3597514 DOI: 10.1371/journal.ppat.1003235] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 01/22/2013] [Indexed: 01/28/2023] Open
Abstract
Following the recognition of pathogen-encoded effectors, plant TIR-NB-LRR immune receptors induce defense signaling by a largely unknown mechanism. We identify a novel and conserved role for the SQUAMOSA PROMOTER BINDING PROTEIN (SBP)-domain transcription factor SPL6 in enabling the activation of the defense transcriptome following its association with a nuclear-localized immune receptor. During an active immune response, the Nicotiana TIR-NB-LRR N immune receptor associates with NbSPL6 within distinct nuclear compartments. NbSPL6 is essential for the N-mediated resistance to Tobacco mosaic virus. Similarly, the presumed Arabidopsis ortholog AtSPL6 is required for the resistance mediated by the TIR-NB-LRR RPS4 against Pseudomonas syringae carrying the avrRps4 effector. Transcriptome analysis indicates that AtSPL6 positively regulates a subset of defense genes. A pathogen-activated nuclear-localized TIR-NB-LRR like N can therefore regulate defense genes through SPL6 in a mechanism analogous to the induction of MHC genes by mammalian immune receptors like CIITA and NLRC5.
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Affiliation(s)
- Meenu S. Padmanabhan
- Department of Plant Biology and The Genome Center, College of Biological Sciences, University of California, Davis, California, United States of America
| | - Shisong Ma
- Department of Plant Biology and The Genome Center, College of Biological Sciences, University of California, Davis, California, United States of America
| | - Tessa M. Burch-Smith
- Department of Biochemistry, Cellular, and Molecular Biology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Kirk Czymmek
- Department of Biological Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, Delaware, United States of America
| | - Peter Huijser
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Savithramma P. Dinesh-Kumar
- Department of Plant Biology and The Genome Center, College of Biological Sciences, University of California, Davis, California, United States of America
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Joo JH, Correia GP, Li JL, Lopez MC, Baker HV, Sugrue SP. Transcriptomic analysis of PNN- and ESRP1-regulated alternative pre-mRNA splicing in human corneal epithelial cells. Invest Ophthalmol Vis Sci 2013; 54:697-707. [PMID: 23299472 DOI: 10.1167/iovs.12-10695] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We investigated the impact of PININ (PNN) and epithelial splicing regulatory protein 1 (ESRP1) on alternative pre-mRNA splicing in the corneal epithelial context. METHODS Isoform-specific RT-PCR assays were performed on wild-type and Pnn knockout mouse cornea. Protein interactions were examined by deconvolution microscopy and co-immunoprecipitation. For genome-wide alternative splicing study, immortalized human corneal epithelial cells (HCET) harboring doxycycline-inducible shRNA against PNN or ESRP1 were created. Total RNA was isolated from four biological replicates of control and knockdown HCET cells, and subjected to hGlue3_0 transcriptome array analysis. RESULTS Pnn depletion in developing mouse corneal epithelium led to disrupted alternative splicing of multiple ESRP-regulated epithelial-type exons. In HCET cells, ESRP1 and PNN displayed close localization in and around nuclear speckles, and their physical association in protein complexes was identified. Whole transcriptome array analysis on ESRP1 or PNN knockdown HCET cells revealed clear alterations in transcript profiles and splicing patterns of specific subsets of genes. Separate RT-PCR validation assays confirmed successfully specific changes in exon usage of several representative splice variants, including PAX6(5a), FOXJ3, ARHGEF11, and SLC37A2. Gene ontologic analyses on ESRP1- or PNN-regulated alternative exons suggested their roles in epithelial phenotypes, such as cell morphology and movement. CONCLUSIONS Our data suggested that ESRP1 and PNN modulate alternative splicing of a specific subset of target genes, but not general splicing events, in HCET cells to maintain or enhance epithelial characteristics.
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Affiliation(s)
- Jeong-Hoon Joo
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, Florida 32610, USA.
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Wang Y, Shang Y. Epigenetic control of epithelial-to-mesenchymal transition and cancer metastasis. Exp Cell Res 2012; 319:160-9. [PMID: 22935683 DOI: 10.1016/j.yexcr.2012.07.019] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/23/2012] [Accepted: 07/25/2012] [Indexed: 12/22/2022]
Abstract
Epithelial-mesenchymal transition (EMT) is vital for morphogenesis during embryonic development and is also critical for the conversion of early stage tumors into invasive malignancies. Several key inducers of EMT are transcription factors that repress the expression of E-cadherin, whose loss is a hallmark of EMT. Epigenetic regulation encompasses three types of changes: DNA methylation, histone modifications, and microRNAs, each of which has been shown to play a key role in controlling epithelial-mesenchymal transition and cancer metastasis. As we gain deeper understanding of epigenetic mechanisms controlling EMT processes and orchestrating all the metastatic steps, we broaden the therapeutic potentials of epigenetic drugs, such as DNA demethylating drugs and histone deacetylase/demethylase inhibitors, which can act upon metastasis-related genes, restoring their expression and biological functions.
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Affiliation(s)
- Yan Wang
- Tianjin Key Laboratory of Medical Epigenetics, Department of Biochemistry and Molecular Biology, Tianjin Medical University, 22 Qixiangtai Road, Tianjin 300070, China
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Hsu SY, Cheng YC, Shih HY, Ouyang P. Dissection of the role of Pinin in the development of zebrafish posterior pharyngeal cartilages. Histochem Cell Biol 2012; 138:127-40. [PMID: 22527695 DOI: 10.1007/s00418-012-0950-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/02/2012] [Indexed: 12/17/2022]
Abstract
Pinin (pnn), a nuclear and desmosome-associated SR-like protein, has been shown to play multiple roles in cell adhesion, transcriptional regulation, pre-mRNA splicing and mRNA export. Because of the embryonic lethality of pnn-deficient mice, here we used the zebrafish system to investigate the functions of pnn. Injection of morpholinos into zebrafish to knockdown pnn resulted in several obvious defective phenotypes, such as short body, bent tail, and an abnormal pigment distribution pattern. Moreover, aberrant blood vessels were formed, and most of the cartilages of pharyngeal arches 3-7 were reduced or absent in pnn morphants. Because most of the defects manifested by pnn morphants were reminiscent of those caused by neural crest-derived malformation, we investigated the effects of pnn deficiency in the development of neural crest cells. Neural crest induction and specification were not hindered in pnn morphants, as revealed by normal expression of early crest gene, sox10. However, the morphants failed to express the pre-chondrogenic gene, sox9a, in cells populating the posterior pharyngeal arches. The reduction of chondrogenic precursors resulted from inhibition of proliferation of neural crest cells, but not from cellular apoptosis or premature differentiation in pnn morphants. These data demonstrate that pnn is essential for the maintenance of subsets of neural crest cells, and that in zebrafish proper cranial neural crest proliferation and differentiation are dependent on pnn expression.
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Affiliation(s)
- Shu-Yuan Hsu
- Transgenic Mouse Core-Lab, Epithelial Biology Laboratory, Department of Anatomy, Graduate Institute of Biomedical Sciences, Chang Gung University Medical College, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan, ROC
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Leu S, Lin YM, Wu CH, Ouyang P. Loss of Pnn expression results in mouse early embryonic lethality and cellular apoptosis through SRSF1-mediated alternative expression of Bcl-xS and ICA**. J Cell Sci 2012; 125:3164-72. [DOI: 10.1242/jcs.100859] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Pinin (Pnn), a serine/arginine-rich (SR)-related protein, has been shown to play multiple roles within eukaryotic cells including in cell-cell adhesion, cell migration, regulation of gene transcription, mRNA export, and alternative splicing. In this study, an attempt to generate mice homozygously deficient in Pnn failed due to early embryonic lethality. To evaluate the effects of loss of Pnn expression on cell survival, RNA interference experiments were performed in MCF-7 cells. With Pnn-depletion, cellular apoptosis and nuclear condensation were observed. In addition, nuclear speckles were disrupted, and expression levels of SR proteins were diminished. RT-PCR analysis showed that alternative splicing patterns of SRSF1 as well as of apoptosis-related genes Bcl-x and ICAD were altered and expression levels of Bim isoforms were modulated in Pnn-depleted cells. Cellular apoptosis induced by Pnn depletion was rescued by overexpression of SRSF1 which also restored generation of Bcl-xL and functionless ICAD. Pnn expression is, therefore, essential for survival of mouse embryos and the breast carcinoma cell line MCF-7. Moreover, Pnn-depletion, modulated by SRSF1, determines cellular apoptosis through activation of expression of pro-apoptotic Bcl-xS transcripts.
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Ataxin-1 occupies the promoter region of E-cadherin in vivo and activates CtBP2-repressed promoter. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:713-22. [PMID: 21315774 DOI: 10.1016/j.bbamcr.2011.01.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 01/25/2011] [Accepted: 01/27/2011] [Indexed: 12/11/2022]
Abstract
Ataxin-1 is a polyglutamine protein of unknown function that is encoded by the ATXN1 gene in humans. To gain insight into the function of ataxin-1, we sought to identify proteins that interact with ataxin-1 through yeast two-hybrid screening. In this study, transcriptional corepressor CtBP2 was identified as a protein that interacted with ataxin-1. CtBP2 and ataxin-1 colocalized in the nucleus of mammalian cells. Since the E-cadherin promoter is a target of CtBP-mediated repression, the relationship between ataxin-1 and the E-cadherin promoter was investigated. Chromatin immunoprecipitation assays showed that CtBP2 and ataxin-1 were recruited to the E-cadherin promoter in mammalian cells. Luciferase assays using E-cadherin promoter reporter constructs revealed that the luciferase activity was enhanced as the level of ataxin-1 protein expression increased. CtBP2 overexpression decreased E-cadherin expression, but expression of ataxin-1 inversely increased the mRNA and protein levels of endogenous E-cadherin. Interestingly, siRNA experiments showed that the transcriptional activation of ataxin-1 was associated with the presence of CtBP2. This study demonstrates that ataxin-1 occupies the promoter region of E-cadherin in vivo and that ataxin-1 activates the promoter in a CtBP2-mediated transcriptional regulation manner. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
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Joo JH, Taxter TJ, Munguba GC, Kim YH, Dhaduvai K, Dunn NW, Degan WJ, Oh SP, Sugrue SP. Pinin modulates expression of an intestinal homeobox gene, Cdx2, and plays an essential role for small intestinal morphogenesis. Dev Biol 2010; 345:191-203. [PMID: 20637749 DOI: 10.1016/j.ydbio.2010.07.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 07/06/2010] [Accepted: 07/07/2010] [Indexed: 01/29/2023]
Abstract
Pinin (Pnn), a nuclear speckle-associated protein, has been shown to function in maintenance of epithelial integrity through altering expression of several key adhesion molecules. Here we demonstrate that Pnn plays a crucial role in small intestinal development by influencing expression of an intestinal homeobox gene, Cdx2. Conditional inactivation of Pnn within intestinal epithelia resulted in significant downregulation of a caudal type homeobox gene, Cdx2, leading to obvious villus dysmorphogenesis and severely disrupted epithelial differentiation. Additionally, in Pnn-deficient small intestine, we observed upregulated Tcf/Lef reporter activity, as well as misregulated expression/distribution of beta-catenin and Tcf4. Since regulation of Cdx gene expression has been closely linked to Wnt/beta-catenin signaling activity, we explored the possibility of Pnn's interaction with beta-catenin, a major effector of the canonical Wnt signaling pathway. Co-immunoprecipitation assays revealed that Pnn, together with its interaction partner CtBP2, a transcriptional co-repressor, was in a complex with beta-catenin. Moreover, both of these proteins were found to be recruited to the proximal promoter area of Cdx2. Taken together, our results suggest that Pnn is essential for tight regulation of Wnt signaling and Cdx2 expression during small intestinal development.
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Affiliation(s)
- Jeong-Hoon Joo
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL, USA
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de Herreros AG, Peiró S, Nassour M, Savagner P. Snail family regulation and epithelial mesenchymal transitions in breast cancer progression. J Mammary Gland Biol Neoplasia 2010; 15:135-47. [PMID: 20455012 PMCID: PMC2930904 DOI: 10.1007/s10911-010-9179-8] [Citation(s) in RCA: 187] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 04/26/2010] [Indexed: 12/12/2022] Open
Abstract
Since its initial description, the interconversion between epithelial and mesenchymal cells (designed as epithelial-mesenchymal or mesenchymal-epithelial transition, EMT or MET, respectively) has received special attention since it provides epithelial cells with migratory features. Different studies using cell lines have identified cytokines, intercellular signaling elements and transcriptional factors capable of regulating this process. Particularly, the identification of Snail family members as key effectors of EMT has opened new ways for the study of this cellular process. In this article we discuss the molecular pathways that control EMT, showing a very tight and interdependent regulation. We also analyze the contribution of EMT and Snail genes in the process of tumorigenesis using the mammary gland as cellular model.
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Affiliation(s)
- Antonio Garcia de Herreros
- IMIM-Hospital del Mar, Parc de Recerca Biomèdica de Barcelona, C/Doctor Aiguader, 88, 08003 Barcelona, Spain.
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Joo JH, Kim YH, Dunn NW, Sugrue SP. Disruption of mouse corneal epithelial differentiation by conditional inactivation of pnn. Invest Ophthalmol Vis Sci 2009; 51:1927-34. [PMID: 19892877 DOI: 10.1167/iovs.09-4591] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose. To investigate the specific role of Pinin (Pnn) in the development of anterior eye segment in mice. Methods. Conditional inactivation of Pnn in the developing surface eye ectoderm and lens was achieved by creating mice carrying a Pnn null and a floxed Pnn allele as well as a Pax6-Cre-GFP (Le-Cre) transgene. The resultant Pnn conditional knockout mice were examined by histologic and immunohistologic approaches. Results. Pax6-Cre-mediated deletion of Pnn resulted in severe malformation of lens placode-derived tissues including cornea and lens. Pnn mutant corneal epithelium displayed the loss of corneal epithelial identity and appeared epidermis-like, downregulating corneal keratins (K12) and ectopically expressing epidermal keratins (K10 and K14). This squamous metaplasia of Pnn mutant corneal epithelium closely correlated with significantly elevated beta-catenin activity and Tcf4 level. In addition, Pnn inactivation also led to misregulated level of p68 RNA helicase in mutant corneal epithelium. Conclusions. These data indicate that Pnn plays an essential role in modulating and/or orchestrating the activities of major developmental factors of anterior eye segments.
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Affiliation(s)
- Jeong-Hoon Joo
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, Florida, USA
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Abstract
Mechanisms of synapse assembly are relevant for our understanding of neuronal development, as well as the processes of learning and memory. The presynaptic active zone membrane is covered by a protein-rich matrix, which is thought to be important for fast vesicle fusion, as well as potentially contributing to synapse stability. By genetic analysis, matrix proteins of active zones from various families have been shown to promote synapse assembly. New evidence shows that the evolutionarily conserved protein RSY-1 (regulator of synaptogenesis 1) locally inhibits active zone assembly to restrict synapse formation to the correct positions during Caenorhabditis elegans development. Thus, the protein interactions that assemble the architecture of the active zone appear to locally integrate not only positive but also negative signals.
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Affiliation(s)
- Stephan J Sigrist
- Genetics, Institute for Biology, Free University Berlin, Takustrasse 6, 14195 Berlin, Germany.
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Abstract
As fundamental units of neuronal communication, chemical synapses are composed of presynaptic and postsynaptic specializations that form at specific locations with defined shape and size. Synaptic assembly must be tightly regulated to prevent overgrowth of the synapse size and number, but the molecular mechanisms that inhibit synapse assembly are poorly understood. We identified regulator of synaptogenesis-1 (RSY-1) as an evolutionarily conserved molecule that locally antagonized presynaptic assembly. The loss of RSY-1 in Caenorhabditis elegans led to formation of extra synapses and recruitment of excessive synaptic material to presynaptic sites. RSY-1 directly interacted with and negatively regulated SYD-2/liprin-alpha, a master assembly molecule that recruits numerous synaptic components to presynaptic sites. RSY-1 also bound and regulated SYD-1, a synaptic protein required for proper functioning of SYD-2. Thus, local inhibitory mechanisms govern synapse formation.
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Affiliation(s)
- Maulik R Patel
- Neurosciences Program, Stanford University, 385 Serra Mall, Herrin Labs, Room 144, Stanford University, Stanford,CA 94305, USA
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41
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Dammer EB, Sewer MB. Phosphorylation of CtBP1 by cAMP-dependent protein kinase modulates induction of CYP17 by stimulating partnering of CtBP1 and 2. J Biol Chem 2008; 283:6925-34. [PMID: 18184656 DOI: 10.1074/jbc.m708432200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the human adrenal cortex, the peptide hormone adrenocorticotropin (ACTH) directs cortisol and adrenal androgen biosynthesis by activating a cAMP/cAMP-dependent protein kinase (PKA) pathway. Carboxyl-terminal binding protein 1 (CtBP1) is a corepressor that regulates transcription of the CYP17 gene by periodically interacting with steroidogenic factor-1 in response to ACTH signaling. Given that CtBP1 function is regulated by NADH binding, we hypothesized that ACTH-stimulated changes in cellular pyridine nucleotide concentrations modulate the ability of CtBP1 to repress CYP17 transcription. Further, we postulated that PKA evokes changes in the phosphorylation status of CtBP1 that control the ability of the protein to bind to steroidogenic factor-1 and the coactivator GCN5 (general control nonderepressed 5) and repress CYP17 gene expression. We show that ACTH alters pyridine nucleotide redox state and identify amino acid residues in CtBP1 that are targeted by PKA and PAK6. Both ACTH/cAMP signaling and NADH/NAD+ ratio stimulate nuclear-cytoplasmic oscillation of both CtBP proteins. We provide evidence that PKA 1) induces metabolic changes in the adrenal cortex and 2) phosphorylates CtBP proteins, particularly CtBP1 at T144, resulting in CtBP protein partnering and ACTH-dependent CYP17 transcription.
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Affiliation(s)
- Eric B Dammer
- School of Biology and Parker H Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332-0230, USA
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42
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Corepressor CtBP and nuclear speckle protein Pnn/DRS differentially modulate transcription and splicing of the E-cadherin gene. Mol Cell Biol 2007; 28:1584-95. [PMID: 18086895 DOI: 10.1128/mcb.00421-07] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
CtBP is a transcriptional corepressor with tumorigenic potential that targets the promoter of the tumor suppressor gene E-cadherin. Pnn/DRS (Pnn) is a "nuclear speckle"-associated protein involved in mRNA processing as well as transcriptional regulation of E-cadherin via its binding to CtBP. Here, we show that CtBP can recruit Pnn to CtBP-associated complexes, resulting in Pnn-dependent chromatin remodeling at the E-cadherin promoter. In addition, CtBP and Pnn can differentially modulate E-cadherin mRNA splicing, with polymerase II serving as an interface in this event. Therefore, the Pnn/CtBP functional interplay represents a novel mechanism linking the corepressor CtBP and Pnn to the transcription-coupled mRNA splicing of a major tumor suppressor gene. Our findings implicate the existence of the molecular switches involved in tumorigenesis, which coordinate promoter-specific events and mRNA processing, by serving as bridging elements between the regulatory complexes both at gene promoters and within the mRNA splicing machineries.
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Holthöfer B, Windoffer R, Troyanovsky S, Leube RE. Structure and function of desmosomes. ACTA ACUST UNITED AC 2007; 264:65-163. [PMID: 17964922 DOI: 10.1016/s0074-7696(07)64003-0] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Desmosomes are prominent adhesion sites that are tightly associated with the cytoplasmic intermediate filament cytoskeleton providing mechanical stability in epithelia and also in several nonepithelial tissues such as cardiac muscle and meninges. They are unique in terms of ultrastructural appearance and molecular composition with cell type-specific variations. The dynamic assembly properties of desmosomes are important prerequisites for the acquisition and maintenance of tissue homeostasis. Disturbance of this equilibrium therefore not only compromises mechanical resilience but also affects many other tissue functions as becomes evident in various experimental scenarios and multiple diseases.
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Affiliation(s)
- Bastian Holthöfer
- Department of Anatomy and Cell Biology, Johannes Gutenberg University, 55128 Mainz, Germany
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Joo JH, Lee YJ, Munguba GC, Park S, Taxter TJ, Elsagga MY, Jackson MR, Oh SP, Sugrue SP. Role of Pinin in neural crest, dorsal dermis, and axial skeleton development and its involvement in the regulation of Tcf/Lef activity in mice. Dev Dyn 2007; 236:2147-58. [PMID: 17654715 DOI: 10.1002/dvdy.21243] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Previous in vitro studies have indicated multiple and varied roles of Pinin (PNN); however, its in vivo role has remained unclear. Here, we report generation of null, hypomorphic, and conditional Pnn alleles in mice. We found that insertion of neomycin-resistance cassette into intron 8 of Pnn resulted in knockdown of Pnn, which allowed Pnn hypomorphic embryos to pass peri-implantation lethality. These mice are lethal at perinatal stages and exhibit defects in the cardiac outflow tract, palate, dorsal dermis, and axial skeleton. Since Wnt/beta-catenin signaling has been shown to play pivotal roles in development of all tissues affected by Pnn hypomorphism, we speculated that Pnn may affect Wnt/beta-catenin signaling. Supporting this view, we demonstrate abnormal activities of Tcf/Lef transcription factors, and alterations in beta-catenin level in multiple Pnn hypomorphic tissues. Taken together, the data suggest that Pnn plays important roles during mouse development through its involvement in regulation of Tcf/Lef activity.
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Affiliation(s)
- Jeong-Hoon Joo
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, Florida 32610, USA
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Wilson BJ, Giguère V. Identification of novel pathway partners of p68 and p72 RNA helicases through Oncomine meta-analysis. BMC Genomics 2007; 8:419. [PMID: 18005418 PMCID: PMC3225811 DOI: 10.1186/1471-2164-8-419] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Accepted: 11/15/2007] [Indexed: 11/18/2022] Open
Abstract
Background The Oncomine™ database is an online collection of microarrays from various sources, usually cancer-related, and contains many "multi-arrays" (collections of analyzed microarrays, in a single study). As there are often many hundreds of tumour samples/microarrays within a single multi-array results from coexpressed genes can be analyzed, and are fully searchable. This gives a potentially significant list of coexpressed genes, which is important to define pathways in which the gene of interest is involved. However, to increase the likelihood of revealing truly significant coexpressed genes we have analyzed their frequency of occurrence over multiple studies (meta-analysis), greatly increasing the significance of results compared to those of a single study. Results We have used the DEAD-box proteins p68(Ddx5) and p72(Ddx17) as models for this coexpression frequency analysis as there are defined functions for these proteins in splicing and transcription (known functions which we could use as a basis for quality control). Furthermore, as these proteins are highly similar, interact together, and may be to some degree functionally redundant, we then analyzed the overlap between coexpressed genes of p68 and p72. This final analysis gave us a highly significant list of coexpressed genes, clustering mainly in splicing and transcription (recapitulating their published roles), but also revealing new pathways such as cytoskeleton remodelling and protein folding. We have further tested a predicted pathway partner, RNA helicase A(Dhx9) in a reciprocal meta-analysis that identified p68 and p72 as being coexpressed, and further show a direct interaction of Dhx9 with p68 and p72, attesting to the predictive nature of this technique. Conclusion In summary we have extended the capabilities of Oncomine™ by analyzing the frequency of coexpressed genes over multiple studies, and furthermore assessing the overlap with a known pathway partner (in this case p68 with p72). We have shown our predictions corroborate previously published studies on p68 and p72, and that novel predictions can be easily tested. These techniques are widely applicable and should increase the quality of data from future meta-analysis studies.
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Affiliation(s)
- Brian J Wilson
- Molecular Oncology Group, Room H5-45, McGill University Health Centre, 687 Pine Avenue West, Montréal, Québec, Canada.
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Peinado H, Olmeda D, Cano A. Snail, Zeb and bHLH factors in tumour progression: an alliance against the epithelial phenotype? Nat Rev Cancer 2007; 7:415-28. [PMID: 17508028 DOI: 10.1038/nrc2131] [Citation(s) in RCA: 2436] [Impact Index Per Article: 143.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The molecular mechanisms that underlie tumour progression are still poorly understood, but recently our knowledge of particular aspects of some of these processes has increased. Specifically, the identification of Snail, ZEB and some basic helix-loop-helix (bHLH) factors as inducers of epithelial-mesenchymal transition (EMT) and potent repressors of E-cadherin expression has opened new avenues of research with potential clinical implications.
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Affiliation(s)
- Héctor Peinado
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM), Instituto de Investigaciones Biomédicas Alberto Sols CSIC-UAM, Arturo Duperier 4, 28029 Madrid, Spain
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47
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Pagan JK, Arnold J, Hanchard KJ, Kumar R, Bruno T, Jones MJK, Richard DJ, Forrest A, Spurdle A, Verdin E, Crossley M, Fanciulli M, Chenevix-Trench G, Young DB, Khanna KK. A novel corepressor, BCoR-L1, represses transcription through an interaction with CtBP. J Biol Chem 2007; 282:15248-57. [PMID: 17379597 DOI: 10.1074/jbc.m700246200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Corepressors play a crucial role in negative gene regulation and are defective in several diseases. BCoR is a corepressor for the BCL6 repressor protein. Here we describe and functionally characterize BCoR-L1, a homolog of BCoR. When tethered to a heterologous promoter, BCoR-L1 is capable of strong repression. Like other corepressors, BCoR-L1 associates with histone deacetylase (HDAC) activity. Specifically, BCoR-L1 coprecipitates with the Class II HDACs, HDAC4, HDAC5, and HDAC7, suggesting that they are involved in its role as a transcriptional repressor. BCoR-L1 also interacts with the CtBP corepressor through a CtBP-interacting motif in its amino terminus. Abrogation of the CtBP binding site within BCoR-L1 partially relieves BCoR-L1-mediated transcriptional repression. Furthermore, BCoR-L1 is located on the E-cadherin promoter, a known CtBP-regulated promoter, and represses the E-cadherin promoter activity in a reporter assay. The inhibition of BCoR-L1 expression by RNA-mediated interference results in derepression of E-cadherin in cells that do not normally express E-cadherin, indicating that BCoR-L1 contributes to the repression of an authentic endogenous CtBP target.
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Affiliation(s)
- Julia K Pagan
- Queensland Institute of Medical Research, 300 Herston Road, Herston 4029, Queensland, Australia
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48
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Dammer EB, Leon A, Sewer MB. Coregulator exchange and sphingosine-sensitive cooperativity of steroidogenic factor-1, general control nonderepressed 5, p54, and p160 coactivators regulate cyclic adenosine 3',5'-monophosphate-dependent cytochrome P450c17 transcription rate. Mol Endocrinol 2006; 21:415-38. [PMID: 17121866 DOI: 10.1210/me.2006-0361] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Transcription of the cytochrome P450 17 (CYP17) gene is regulated by cAMP-dependent binding of steroidogenic factor-1 (SF-1) to its promoter in the adrenal cortex. Using temporal chromatin immunoprecipitation and mammalian two-hybrid experiments, we establish the reciprocal presence of coactivators [general control nonderepressed (GCN5), cAMP response element-binding protein-binding protein, p300, p300/cAMP response element-binding protein-binding protein CBP associated factor, p160s, polypyrimidine tract associated splicing factor, and p54(nrb)], corepressors (class I histone deacetylases, receptor interacting protein, nuclear receptor corepressor, and Sin3A), and SWI/SNF (human homolog of yeast mating type switching/sucrose nonfermenting) and imitation SWI chromatin remodeling ATPases on the CYP17 promoter during transcription cycles in the H295R adrenocortical cell line. A ternary GCN5/SRC-1/SF-1 complex forms on the CYP17 promoter with cAMP-dependence within 30 min of cAMP stimulation, and corresponds with SWI/SNF chromatin remodeling. This complex is sensitive to the SF-1 antagonist sphingosine and results in decreased transcription of CYP17. GCN5 acetyltransferase activity and carboxy terminus binding proteins alternatively mediate disassembly of the complex. This work establishes the temporal order of cAMP-induced events on the promoter of a key steroidogenic gene during SF-1-mediated transcription.
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Affiliation(s)
- Eric B Dammer
- School of Biology, Parker H. Petit Institute for Bioengineering & Biosciences, Georgia Institute of Technology, 310 Ferst Drive, Atlanta, Georgia 30332-0230, USA
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49
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Bergman LM, Morris L, Darley M, Mirnezami AH, Gunatilake SC, Blaydes JP. Role of the unique N-terminal domain of CtBP2 in determining the subcellular localisation of CtBP family proteins. BMC Cell Biol 2006; 7:35. [PMID: 16999872 PMCID: PMC1592084 DOI: 10.1186/1471-2121-7-35] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Accepted: 09/25/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND CtBP1 and CtBP2 are transcriptional co-repressors that modulate the activity of a large number of transcriptional repressors via the recruitment of chromatin modifiers. Many CtBP-regulated proteins are involved in pathways associated with tumorigenesis, including TGF-beta and Wnt signalling pathways and cell cycle regulators such as RB/p130 and HDM2, as well as adenovirus E1A. CtBP1 and CtBP2 are highly similar proteins, although evidence is emerging that their activity can be differentially regulated, particularly through the control of their subcellular localisation. CtBP2s from diverse species contain a unique N-terminus, absent in CtBP1 that plays a key role in controlling the nuclear-cytoplasmic distribution of the protein. RESULTS Here we show that amino acids (a.a.) 4-14 of CtBP2 direct CtBP2 into an almost exclusively nuclear distribution in cell lines of diverse origins. Whilst this sequence contains similarity to known nuclear localisation motifs, it cannot drive nuclear localisation of a heterologous protein, but rather has been shown to function as a p300 acetyltransferase-dependent nuclear retention sequence. Here we define the region of CtBP2 required to co-operate with a.a. 4-14 to promote CtBP2 nuclear accumulation as being within a.a. 1-119. In addition, we show that a.a. 120-445 of CtBP2 can also promote CtBP2 nuclear accumulation, independently of a.a. 4-14. Finally, CtBP1 and CtBP2 can form heterodimers, and we show that the interaction with CtBP2 is one mechanism whereby CtBP1 can be recruited to the nucleus. CONCLUSION Together, these findings represent key distinctions in the regulation of the functions of CtBP family members that may have important implications as to their roles in development, and cell differentiation and survival.
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Affiliation(s)
- Lee M Bergman
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Laila Morris
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Matthew Darley
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Alexander H Mirnezami
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Samal C Gunatilake
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Jeremy P Blaydes
- Cancer Sciences Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK
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Quinlan KGR, Nardini M, Verger A, Francescato P, Yaswen P, Corda D, Bolognesi M, Crossley M. Specific recognition of ZNF217 and other zinc finger proteins at a surface groove of C-terminal binding proteins. Mol Cell Biol 2006; 26:8159-72. [PMID: 16940172 PMCID: PMC1636751 DOI: 10.1128/mcb.00680-06] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Numerous transcription factors recruit C-terminal binding protein (CtBP) corepressors. We show that the large zinc finger protein ZNF217 contacts CtBP. ZNF217 is encoded by an oncogene frequently amplified in tumors. ZNF217 contains a typical Pro-X-Asp-Leu-Ser (PXDLS) motif that binds in CtBP's PXDLS-binding cleft. However, ZNF217 also contains a second motif, Arg-Arg-Thr (RRT), that binds a separate surface on CtBP. The crystal structure of CtBP bound to an RRTGAPPAL peptide shows that it contacts a surface crevice distinct from the PXDLS binding cleft. Interestingly, both PXDLS and RRT motifs are also found in other zinc finger proteins, such as RIZ. Finally, we show that ZNF217 represses several promoters, including one from a known CtBP target gene, and mutations preventing ZNF217's contact with CtBP reduce repression. These results identify a new CtBP interaction motif and establish ZNF217 as a transcriptional repressor protein that functions, at least in part, by associating with CtBP.
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Affiliation(s)
- Kate G R Quinlan
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney, NSW 2006, Australia
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