1
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Ferrer J, Dimitrova N. Transcription regulation by long non-coding RNAs: mechanisms and disease relevance. Nat Rev Mol Cell Biol 2024; 25:396-415. [PMID: 38242953 PMCID: PMC11045326 DOI: 10.1038/s41580-023-00694-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2023] [Indexed: 01/21/2024]
Abstract
Long non-coding RNAs (lncRNAs) outnumber protein-coding transcripts, but their functions remain largely unknown. In this Review, we discuss the emerging roles of lncRNAs in the control of gene transcription. Some of the best characterized lncRNAs have essential transcription cis-regulatory functions that cannot be easily accomplished by DNA-interacting transcription factors, such as XIST, which controls X-chromosome inactivation, or imprinted lncRNAs that direct allele-specific repression. A growing number of lncRNA transcription units, including CHASERR, PVT1 and HASTER (also known as HNF1A-AS1) act as transcription-stabilizing elements that fine-tune the activity of dosage-sensitive genes that encode transcription factors. Genetic experiments have shown that defects in such transcription stabilizers often cause severe phenotypes. Other lncRNAs, such as lincRNA-p21 (also known as Trp53cor1) and Maenli (Gm29348) contribute to local activation of gene transcription, whereas distinct lncRNAs influence gene transcription in trans. We discuss findings of lncRNAs that elicit a function through either activation of their transcription, transcript elongation and processing or the lncRNA molecule itself. We also discuss emerging evidence of lncRNA involvement in human diseases, and their potential as therapeutic targets.
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Affiliation(s)
- Jorge Ferrer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Nadya Dimitrova
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
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2
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LIU GANG, SHI LEI, WANG BIN, WU ZEHUI, ZHAO HAIYUAN, ZHAO TIANYU, SHI LIANGHUI. Role of oncogenic long noncoding RNA KCNQ1OT1 in colon cancer. Oncol Res 2024; 32:585-596. [PMID: 38361755 PMCID: PMC10865742 DOI: 10.32604/or.2023.029349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 09/05/2023] [Indexed: 02/17/2024] Open
Abstract
The role of lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in colon cancer involves various tumorigenic processes and has been studied widely. However, the mechanism by which it promotes colon cancer remains unclear. Retroviral vector pSEB61 was retrofitted in established HCT116-siKCN and SW480-siKCN cells to silence KCNQ1OT1. Cellular proliferation was measured using CCK8 assay, and flow cytometry (FCM) detected cell cycle changes. RNA sequencing (RNA-Seq) analysis showed differentially expressed genes (DEGs). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out to analyze enriched functions and signaling pathways. RT-qPCR, immunofluorescence, and western blotting were carried out to validate downstream gene expressions. The effects of tumorigenesis were evaluated in BALB/c nude mice by tumor xenografts. Our data revealed that the silencing of KCNQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M phase. RNA-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell cycle. RT-qPCR, immunofluorescence, and western blotting confirmed downstream CCNE2 and PCNA gene expressions. HCT116-siKCN cells significantly suppressed tumorigenesis in BALB/c nude mice. Our study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer.
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Affiliation(s)
- GANG LIU
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - LEI SHI
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - BIN WANG
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - ZEHUI WU
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - HAIYUAN ZHAO
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - TIANYU ZHAO
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, Chongqing, 401147, China
| | - LIANGHUI SHI
- Department of Gastrointestinal Surgery, First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
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3
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Hjazi A, Ghaffar E, Asghar W, Alauldeen Khalaf H, Ikram Ullah M, Mireya Romero-Parra R, Hussien BM, Abdulally Abdulhussien Alazbjee A, Singh Bisht Y, Fakri Mustafa Y, Reza Hosseini-Fard S. CDKN2B-AS1 as a novel therapeutic target in cancer: Mechanism and clinical perspective. Biochem Pharmacol 2023; 213:115627. [PMID: 37257723 DOI: 10.1016/j.bcp.2023.115627] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/11/2023] [Accepted: 05/23/2023] [Indexed: 06/02/2023]
Abstract
Long non-coding RNAs (lncRNA) have been identified as essential components having considerable modulatory impactson biological activities through altering gene transcription, epigenetic changes, and protein translation. Cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1), a recently discovered lncRNA, was shown to be substantially elevated in various cancers.Furthermore, via modulation ofvarious signalingaxes, it is effectively connected to the control of critical cancer-associatedbiological pathways likecell proliferation, apoptosis, cell cycle, epithelial-mesenchymal transition(EMT), invasion, and migration. Considering the crucial functions ofCDKN2B-AS1in cancer onset and development, this lncRNA offers immense therapeutic implications for usage as a new diagnostic or treatment approach. In this article, we evaluate the most recent discoveries made into the functions of the lncRNA CDKN2B-AS1 in cancer, in addition to its prospect asbeneficial properties,prognostic anddiagnostic biomarkersin the cancer-related treatment, emphasizingits participation in a broad network of signalingaxes whichcould affectvariouscancers and investigating its promising therapeutic possibility.
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Affiliation(s)
- Ahmed Hjazi
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
| | | | | | | | - Muhammad Ikram Ullah
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 75471, Aljouf, Saudi Arabia
| | | | - Beneen M Hussien
- Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf, Iraq
| | | | - Yashwant Singh Bisht
- Uttaranchal Institute of Technology, Uttaranchal University, Dehradun 248007, India
| | - Yasser Fakri Mustafa
- Department of Pharmaceutical Chemistry, College of Pharmacy, University of Mosul, Mosul 41001, Iraq
| | - Seyed Reza Hosseini-Fard
- Biochemistry Department, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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4
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Nair J, Maheshwari A. Non-coding RNAs in Necrotizing Enterocolitis- A New Frontier? Curr Pediatr Rev 2022; 18:25-32. [PMID: 34727861 DOI: 10.2174/1573396317666211102093646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 06/30/2021] [Accepted: 09/01/2021] [Indexed: 11/22/2022]
Abstract
With the recognition that only 2% of the human genome encodes for a protein, a large part of the "non-coding" portion is now being evaluated for a regulatory role in cellular processes. These non-coding RNAs (ncRNAs) are subdivided based on the size of the nucleotide transcript into microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), but most of our attention has been focused on the role of microRNAs (miRNAs) in human health and disease. Necrotizing enterocolitis (NEC), an inflammatory bowel necrosis affecting preterm infants, has a multifactorial, unclear etiopathogenesis, and we have no specific biomarkers for diagnosis or the impact of directed therapies. The information on ncRNAs, in general, and particularly in NEC, is limited. Increasing information from other inflammatory bowel disorders suggests that these transcripts may play an important role in intestinal inflammation. Here, we review ncRNAs for definitions, classifications, and possible roles in prematurity and NEC using some preliminary information from our studies and from an extensive literature search in multiple databases including PubMed, EMBASE, and Science Direct. miRNAs will be described in another manuscript in this series, hence in this manuscript we mainly focus on lncRNAs.
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Affiliation(s)
- Jayasree Nair
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Akhil Maheshwari
- Department of Pediatrics, Johns Hopkins University, Baltimore, MD, USA
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5
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Abstract
Genomic imprinting is a parent-of-origin dependent phenomenon that restricts transcription to predominantly one parental allele. Since the discovery of the first long noncoding RNA (lncRNA), which notably was an imprinted lncRNA, a body of knowledge has demonstrated pivotal roles for imprinted lncRNAs in regulating parental-specific expression of neighboring imprinted genes. In this Review, we will discuss the multiple functionalities attributed to lncRNAs and how they regulate imprinted gene expression. We also raise unresolved questions about imprinted lncRNA function, which may lead to new avenues of investigation. This Review is dedicated to the memory of Denise Barlow, a giant in the field of genomic imprinting and functional lncRNAs. With her passion for understanding the inner workings of science, her indominable spirit and her consummate curiosity, Denise blazed a path of scientific investigation that made many seminal contributions to genomic imprinting and the wider field of epigenetic regulation, in addition to inspiring future generations of scientists.
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Affiliation(s)
- William A. MacDonald
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- Rangos Research Center, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Mellissa R. W. Mann
- Department of Obstetrics, Gynaecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
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6
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Enteghami M, Ghorbani M, Zamani M, Galehdari H. HOXC10 is significantly overexpressed in colorectal cancer. Biomed Rep 2020; 13:18. [PMID: 32765857 DOI: 10.3892/br.2020.1325] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 11/13/2019] [Indexed: 01/02/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most common types of cancer in world and has a high rate of mortality. The majority of cases of CRC are sporadic; however, factors such as age, a family history of inflammatory diseases, diet, lifestyle and genetics increase the risk. HOX genes and lncRNAs are two classes of genes, and alterations in the expression levels of these genes are significantly associated with numerous different types of cancer. In the present study, the expression levels of HOXC10, HOXC-AS3, HOTAIR, HOXC13 and HOXC13-AS in tumor tissues were compared with normal healthy tissues in patients with CRC. Paired tumor and normal tissues were collected from 39 patients with CRC, and reverse transcription-quantitative PCR was used the expression of HOXC-AS3, HOXC13 and HOXC10 in the tumor tissues compared with the respective normal tissues. Expression of these genes were increased in the tumor tissues compared with normal tissues; however, the difference was only significant for HOXC10. Additionally, there was a strong and significant correlation between the expression of HOTAIR and HOXC13, a moderate and significant correlation between the expression of HOTAIR and HOXC13-AS, and between HOXC13 and HOXC13-AS genes. The expression of HOXC10 was significantly higher in tumor tissues compared with the normal tissues; whereas the upregulation of HOXC-AS3 and HOXC13 were not significant. Only the correlation between the expression of HOTAIR and HOXC13 was strong and significant. As HOXC10 expression was significantly upregulated in the tumor tissues relative to normal tissues, it may serve as a biomarker for the diagnosis of CRC and as a potential therapeutic target.
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Affiliation(s)
- Mahboubeh Enteghami
- Department of Genetics, Faculty of Sciences, Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan 6155661112, Iran
| | - Mahsa Ghorbani
- Department of Genetics, Faculty of Sciences, Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan 6155661112, Iran
| | - Mina Zamani
- Department of Genetics, Faculty of Sciences, Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan 6155661112, Iran
| | - Hamid Galehdari
- Department of Genetics, Faculty of Sciences, Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan 6155661112, Iran
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7
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Abstract
In 1993, Denise Barlow proposed that genomic imprinting might have arisen from a host defense mechanism designed to inactivate retrotransposons. Although there were few examples at hand, she suggested that there should be maternal-specific and paternal-specific factors involved, with cognate imprinting boxes that they recognized; furthermore, the system should build on conserved biochemical factors, including DNA methylation, and maternal control should predominate for imprints. Here, we revisit this hypothesis in the light of recent advances in our understanding of host defense and DNA methylation and in particular, the link with Krüppel-associated box–zinc finger (KRAB-ZF) proteins.
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Affiliation(s)
- Miroslava Ondičová
- School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Rebecca J. Oakey
- Department of Medical & Molecular Genetics, King’s College London, Guy’s Hospital, London, United Kingdom
| | - Colum P. Walsh
- School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
- * E-mail:
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8
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Lee H, Zhang Z, Krause HM. Long Noncoding RNAs and Repetitive Elements: Junk or Intimate Evolutionary Partners? Trends Genet 2019; 35:892-902. [PMID: 31662190 DOI: 10.1016/j.tig.2019.09.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/22/2019] [Accepted: 09/13/2019] [Indexed: 12/27/2022]
Abstract
Our recent ability to sequence entire genomes, along with all of their transcribed RNAs, has led to the surprising finding that only ∼1% of the human genome is used to encode proteins. This finding has led to vigorous debate over the functional importance of the transcribed but untranslated portions of the genome. Currently, scientists tend to assume coding genes are functional until proven not to be, while the opposite is true for noncoding genes. This review takes a new look at the evidence for and against widespread noncoding gene functionality. We focus in particular on long noncoding RNA (noncoding RNAs longer than 200 nucleotides) genes and their 'junk' associates, transposable elements, and satellite repeats. Taken together, the suggestion put forward is that more of this junk DNA may be functional than nonfunctional and that noncoding RNAs and transposable elements act symbiotically to drive evolution.
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Affiliation(s)
- Hyunmin Lee
- Donnelly Centre, University of Toronto, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Zhaolei Zhang
- Donnelly Centre, University of Toronto, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Department of Computer Science, University of Toronto, Toronto, ON, Canada
| | - Henry M Krause
- Donnelly Centre, University of Toronto, Toronto, ON, Canada; Department of Computer Science, University of Toronto, Toronto, ON, Canada.
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9
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Gong W, Yang L, Wang Y, Xian J, Qiu F, Liu L, Lin M, Feng Y, Zhou Y, Lu J. Analysis of Survival-Related lncRNA Landscape Identifies A Role for LINC01537 in Energy Metabolism and Lung Cancer Progression. Int J Mol Sci 2019; 20:ijms20153713. [PMID: 31374807 PMCID: PMC6696180 DOI: 10.3390/ijms20153713] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 02/07/2023] Open
Abstract
Many long non-coding RNAs (lncRNAs) have emerged as good biomarkers and potential therapeutic targets for various cancers. We aimed to get a detailed understanding of the lncRNA landscape that is associated with lung cancer survival. A comparative analysis between our RNA sequencing (RNA-seq) data and TCGA datasets was conducted to reveal lncRNAs with significant correlations with lung cancer survival and then the association of the most promising lncRNA was validated in a cohort of 243 lung cancer patients. Comparing RNA-seq data with TCGA ones, 84 dysregulated lncRNAs were identified in lung cancer tissues, among which 10 lncRNAs were significantly associated with lung cancer survival. LINC01537 was the most significant one (p = 2.95 × 10−6). Validation analysis confirmed the downregulation of LINC01537 in lung cancer. LINC01537 was observed to inhibit tumor growth and metastasis. It also increased cellular sensitivity to nilotinib. PDE2A (phosphodiesterase 2A) was further identified to be a target of LINC01537 and it was seen that LINC01537 promoted PDE2A expression via RNA–RNA interaction to stabilize PDE2A mRNA and thus echoed effects of PDE2A on energy metabolism including both Warburg effect and mitochondrial respiration. Other regulators of tumor energy metabolism were also affected by LINC01537. These results elucidate a suppressed role of LINC01537 in lung cancer development involving tumor metabolic reprogramming, and we believe that it might be a biomarker for cancer survival prediction and therapy.
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Affiliation(s)
- Wei Gong
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Lei Yang
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China.
| | - Yuanyuan Wang
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Jianfeng Xian
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Fuman Qiu
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Li Liu
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Mingzhu Lin
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Yingyi Feng
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China
| | - Yifeng Zhou
- Department of Genetics, Medical College of Soochow University, 1 Shizi Road, Suzhou 215123, China
| | - Jiachun Lu
- The State Key Lab of Respiratory Disease, The institute for Chemical Carcinogenesis, Collaborative Innovation Center for Environmental Toxicity, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China.
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10
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Xie H, Wang H, Li X, Ji H, Xu Y. ZEA exerts toxic effects on reproduction and development by mediating Dio3os in mouse endometrial stromal cells. J Biochem Mol Toxicol 2019; 33:e22310. [PMID: 30790392 DOI: 10.1002/jbt.22310] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 01/09/2019] [Accepted: 01/29/2019] [Indexed: 11/07/2022]
Abstract
Zearalenone (ZEA) and imprinted long noncoding RNAs (lncRNAs) are both closely related to reproduction and development. However, whether they have connections in regulating reproduction and development is not clear yet. The aim of this research is to investigate their relationship. lncRNA microarray was performed to analyze differentially expressed genes, and real-time quantitative polymerase chain reaction (PCR) was used to verify the accuracy of microarray analysis. Meanwhile, the technologies of rapid amplification of cDNA ends, RNA fluorescence in situ hybridization and bioinformatics were adopted to characterize the selected lncRNA. Analysis of lncRNA microarray showed lncRNAs and messenger RNAs related to reproduction and development were significantly differently expressed, and Dio3os was probably the target lncRNA. Then, the experiment of real-time quantitative PCR verified the accuracy of microarray data. Characterization of Dio3os showed Dio3os, an antisense lncRNA with 2312 bp and 15 open reading frames, was enriched in the cytoplasm. Our findings suggest ZEA probably exerts toxic effects on reproduction and development by mediating Dio3os.
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Affiliation(s)
- Haiqiang Xie
- Department of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Huan Wang
- Department of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Xiaodan Li
- Department of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Haijing Ji
- Department of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Yinxue Xu
- Department of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
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11
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Li M, Wang Y, Cheng L, Niu W, Zhao G, Raju JK, Huo J, Wu B, Yin B, Song Y, Bu R. Long non-coding RNAs in renal cell carcinoma: A systematic review and clinical implications. Oncotarget 2018; 8:48424-48435. [PMID: 28467794 PMCID: PMC5564659 DOI: 10.18632/oncotarget.17053] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 03/20/2017] [Indexed: 12/27/2022] Open
Abstract
Renal cell carcinoma is one of the most common malignancy in adults, its prognosis is poor in an advanced stage and early detection is difficult due to the lack of molecular biomarkers. The identification of novel biomarkers for RCC is an urgent and meaningful project. Long non-coding RNA (lncRNA) is transcribed from genomic regions with a minimum length of 200 bases and limited protein-coding potential. Recently, lncRNAs have been greatly studied in a variety of cancer types. They participate in a wide variety of biological processes including cancer biology. In this review, we provide a new insight of the profiling of lncRNAs in RCC and their roles in renal carcinogenesis, with an emphasize on their potential in diagnosis, prognosis and potential roles in RCC therapy.
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Affiliation(s)
- Ming Li
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Ying Wang
- Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China.,Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Liang Cheng
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Wanting Niu
- Department of Orthopedics, Brigham and Women's Hospital, VA Boston Healthcare System, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Guoan Zhao
- School of Network Education, Beijing University of Posts and Telecommunications, Hebei, Beijing 100088, P.R. China
| | - Jithin K Raju
- Department of Clinical Medicine, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Jun Huo
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Bin Wu
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Bo Yin
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Yongsheng Song
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Renge Bu
- Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
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12
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Chen H, Zhang K, Lu J, Wu G, Yang H, Chen K. Comprehensive analysis of mRNA-lncRNA co-expression profile revealing crucial role of imprinted gene cluster DLK1-MEG3 in chordoma. Oncotarget 2017; 8:112623-112635. [PMID: 29348851 PMCID: PMC5762536 DOI: 10.18632/oncotarget.22616] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 09/03/2017] [Indexed: 12/15/2022] Open
Abstract
Chordoma is a rare bone tumor with high recurrence rate, but the mechanism of its development is unclear. Long non-coding RNAs(lncRNAs) are recently revealed to be regulators in a variety of biological processed by targeting on mRNA transcription. Their expression profile and function in chordoma have not been investigated yet. In this study, we firstly performed the comprehensive analysis of the lncRNA and coding genes expression analysis with three chordoma samples and three fetal nucleus pulposus tissues. lncRNA and gene microarrays were used to determine the differentially expressed lncRNAs and protein coding genes. 2786 lncRNAs and 3286 coding genes were significantly up-regulated in chordoma, while 2042 lncRNAs and 1006 coding genes were down-regulated. Pearson correlation analysis was conducted to correlate differentially expressed lncRNAs with protein coding genes, indicating a comprehensive lncRNA-coding gene co-expression network in chordoma. Cis-correlation analysis showed that various transcripts of MEG3 and MEG8 were paired with the most differentially expressed gene DLK1. As located in the same locus, we further analyzed the miRNA clusters in this region, and identified that 61.22% of these miRNAs were significantly down-regulated, implying the silence of the imprinted gene cluster DLK1-MEG3. Overexpression of MEG3 suppressed the proliferation of chordoma cells. Our study pointed out the potential role of lncRNAs in chordoma, presented the lncRNA-coding genes co-expression profile, and revealed that imprinted gene cluster DLK1-MEG3 contributes to the pathogenesis of chordoma development.
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Affiliation(s)
- Hao Chen
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Kai Zhang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Jian Lu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Guizhong Wu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Huilin Yang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China.,Institute of Orthopedics, Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Kangwu Chen
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
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13
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Exploring the secrets of long noncoding RNAs. Int J Mol Sci 2015; 16:5467-96. [PMID: 25764159 PMCID: PMC4394487 DOI: 10.3390/ijms16035467] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/22/2015] [Accepted: 03/03/2015] [Indexed: 12/14/2022] Open
Abstract
High-throughput sequencing has revealed that the majority of RNAs have no capacity to encode protein. Among these non-coding transcripts, recent work has focused on the roles of long noncoding RNAs (lncRNAs) of >200 nucleotides. Although many of their attributes, such as patterns of expression, remain largely unknown, lncRNAs have key functions in transcriptional, post-transcriptional, and epigenetic gene regulation; Also, new work indicates their functions in scaffolding ribonuclear protein complexes. In plants, genome-wide identification of lncRNAs has been conducted in several species, including Zea mays, and recent research showed that lncRNAs regulate flowering time in the photoperiod pathway, and function in nodulation. In this review, we discuss the basic mechanisms by which lncRNAs regulate key cellular processes, using the large body of knowledge on animal and yeast lncRNAs to illustrate the significance of emerging work on lncRNAs in plants.
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Sun J, Li W, Sun Y, Yu D, Wen X, Wang H, Cui J, Wang G, Hoffman AR, Hu JF. A novel antisense long noncoding RNA within the IGF1R gene locus is imprinted in hematopoietic malignancies. Nucleic Acids Res 2014; 42:9588-601. [PMID: 25092925 PMCID: PMC4150754 DOI: 10.1093/nar/gku549] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Dysregulation of the insulin-like growth factor type I receptor (IGF1R) has been implicated in the progression and therapeutic resistance of malignancies. In acute myeloid leukemia (AML) cells, IGF1R is one of the most abundantly phosphorylated receptor tyrosine kinases, promoting cell growth through the PI3K/Akt signaling pathway. However, little is known regarding the molecular mechanisms underlying IGF1R gene dysregulation in cancer. We discovered a novel intragenic long noncoding RNA (lncRNA) within the IGF1R locus, named IRAIN, which is transcribed in an antisense direction from an intronic promoter. The IRAIN lncRNA was expressed exclusively from the paternal allele, with the maternal counterpart being silenced. Using both reverse transcription-associated trap and chromatin conformation capture assays, we demonstrate that this lncRNA interacts with chromatin DNA and is involved in the formation of an intrachromosomal enhancer/promoter loop. Knockdown of IRAIN lncRNA with shRNA abolishes this intrachromosomal interaction. In addition, IRAIN was downregulated both in leukemia cell lines and in blood obtained from high-risk AML patients. These data identify IRAIN as a new imprinted lncRNA that is involved in long-range DNA interactions.
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Affiliation(s)
- Jingnan Sun
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - Wei Li
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Yunpeng Sun
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Dehai Yu
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - Xue Wen
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Hong Wang
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - Jiuwei Cui
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Guanjun Wang
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Andrew R Hoffman
- Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - Ji-Fan Hu
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
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Li X, Wu Z, Fu X, Han W. lncRNAs: insights into their function and mechanics in underlying disorders. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 762:1-21. [PMID: 25485593 DOI: 10.1016/j.mrrev.2014.04.002] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 04/27/2014] [Accepted: 04/28/2014] [Indexed: 12/14/2022]
Abstract
Genomes of complex organisms are characterized by the pervasive expression of different types of noncoding RNAs (ncRNAs). lncRNAs constitute a large family of long—arbitrarily defined as being longer than 200 nucleotides—ncRNAs that are expressed throughout the cell and that include thousands of different species. While these new and enigmatic players in the complex transcriptional milieu are encoded by a significant proportion of the genome, their functions are mostly unknown at present. Existing examples suggest that lncRNAs have fulfilled a wide variety of regulatory roles at almost every stage of gene expression. These roles, which encompass signal, decoy, scaffold and guide capacities, derive from folded modular domains in lncRNAs. Early discoveries support a paradigm in which lncRNAs regulate transcription networks via chromatin modulation, but new functions are steadily emerging. Given the biochemical versatility of RNA, lncRNAs may be used for various tasks, including posttranscriptional processing. In addition, long intergenic ncRNAs (lincRNAs) are strongly enriched for trait-associated SNPs, which suggest a new mechanism by which intergenic trait-associated regions might function. Moreover, multiple lines of evidence increasingly link mutations and dysregulations of lncRNAs to diverse human diseases, especially disorders related to aging. In this article, we review the current state of the knowledge of the lncRNA field, discussing what is known about the genomic contexts, biological functions and mechanisms of action of these molecules. We highlight the growing evidence for the importance of lncRNAs in diverse human disorders and the indications that their dysregulations and mutations underlie some aging-related disorders. Finally, we consider the potential medical implications, and future potential in the application of lncRNAs as therapeutic targets and diagnostic markers.
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Affiliation(s)
- Xiaolei Li
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Sciences, Chinese PLA General Hospital, Beijing 100853, China
| | - Zhiqiang Wu
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Sciences, Chinese PLA General Hospital, Beijing 100853, China
| | - Xiaobing Fu
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Sciences, Chinese PLA General Hospital, Beijing 100853, China; Key Laboratory of Wound Healing and Cell Biology, Institute of Burns, The First Affiliated Hospital to the Chinese PLA General Hospital, Trauma Center of Postgraduate Medical School, Beijing 100037, China.
| | - Weidong Han
- Department of Molecular Biology, Institute of Basic Medicine, School of Life Sciences, Chinese PLA General Hospital, Beijing 100853, China.
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Hoeppner MP, Lundquist A, Pirun M, Meadows JRS, Zamani N, Johnson J, Sundström G, Cook A, FitzGerald MG, Swofford R, Mauceli E, Moghadam BT, Greka A, Alföldi J, Abouelleil A, Aftuck L, Bessette D, Berlin A, Brown A, Gearin G, Lui A, Macdonald JP, Priest M, Shea T, Turner-Maier J, Zimmer A, Lander ES, di Palma F, Lindblad-Toh K, Grabherr MG. An improved canine genome and a comprehensive catalogue of coding genes and non-coding transcripts. PLoS One 2014; 9:e91172. [PMID: 24625832 PMCID: PMC3953330 DOI: 10.1371/journal.pone.0091172] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 02/08/2014] [Indexed: 12/22/2022] Open
Abstract
The domestic dog, Canis familiaris, is a well-established model system for mapping trait and disease loci. While the original draft sequence was of good quality, gaps were abundant particularly in promoter regions of the genome, negatively impacting the annotation and study of candidate genes. Here, we present an improved genome build, canFam3.1, which includes 85 MB of novel sequence and now covers 99.8% of the euchromatic portion of the genome. We also present multiple RNA-Sequencing data sets from 10 different canine tissues to catalog ∼175,000 expressed loci. While about 90% of the coding genes previously annotated by EnsEMBL have measurable expression in at least one sample, the number of transcript isoforms detected by our data expands the EnsEMBL annotations by a factor of four. Syntenic comparison with the human genome revealed an additional ∼3,000 loci that are characterized as protein coding in human and were also expressed in the dog, suggesting that those were previously not annotated in the EnsEMBL canine gene set. In addition to ∼20,700 high-confidence protein coding loci, we found ∼4,600 antisense transcripts overlapping exons of protein coding genes, ∼7,200 intergenic multi-exon transcripts without coding potential, likely candidates for long intergenic non-coding RNAs (lincRNAs) and ∼11,000 transcripts were reported by two different library construction methods but did not fit any of the above categories. Of the lincRNAs, about 6,000 have no annotated orthologs in human or mouse. Functional analysis of two novel transcripts with shRNA in a mouse kidney cell line altered cell morphology and motility. All in all, we provide a much-improved annotation of the canine genome and suggest regulatory functions for several of the novel non-coding transcripts.
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Affiliation(s)
- Marc P. Hoeppner
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Andrew Lundquist
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Mono Pirun
- Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Jennifer R. S. Meadows
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Neda Zamani
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jeremy Johnson
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Görel Sundström
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - April Cook
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michael G. FitzGerald
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Ross Swofford
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Evan Mauceli
- Boston Children's Hospital, Boston, Massachusetts, United States of America
| | | | - Anna Greka
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Jessica Alföldi
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Amr Abouelleil
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Lynne Aftuck
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Daniel Bessette
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Aaron Berlin
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Adam Brown
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Gary Gearin
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Annie Lui
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | | | - Margaret Priest
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Terrance Shea
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Jason Turner-Maier
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Andrew Zimmer
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Eric S. Lander
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Federica di Palma
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Vertebrate and Health Genomics, The Genome Analysis Centre, Norwich, United Kingdom
| | - Kerstin Lindblad-Toh
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail: (KL-T); (MGG)
| | - Manfred G. Grabherr
- Science for Life Laboratories, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail: (KL-T); (MGG)
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18
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Hannula-Jouppi K, Muurinen M, Lipsanen-Nyman M, Reinius LE, Ezer S, Greco D, Kere J. Differentially methylated regions in maternal and paternal uniparental disomy for chromosome 7. Epigenetics 2013; 9:351-65. [PMID: 24247273 PMCID: PMC4053454 DOI: 10.4161/epi.27160] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
DNA methylation is a hallmark of genomic imprinting and differentially methylated regions (DMRs) are found near and in imprinted genes. Imprinted genes are expressed only from the maternal or paternal allele and their normal balance can be disrupted by uniparental disomy (UPD), the inheritance of both chromosomes of a chromosome pair exclusively from only either the mother or the father. Maternal UPD for chromosome 7 (matUPD7) results in Silver-Russell syndrome (SRS) with typical features and growth retardation, but no gene has been conclusively implicated in SRS. In order to identify novel DMRs and putative imprinted genes on chromosome 7, we analyzed eight matUPD7 patients, a segmental matUPD7q31-qter, a rare patUPD7 case and ten controls on the Infinium HumanMethylation450K BeadChip with 30 017 CpG methylation probes for chromosome 7. Genome-scale analysis showed highly significant clustering of DMRs only on chromosome 7, including the known imprinted loci GRB10, SGCE/PEG10, and PEG/MEST. We found ten novel DMRs on chromosome 7, two DMRs for the predicted imprinted genes HOXA4 and GLI3 and one for the disputed imprinted gene PON1. Quantitative RT-PCR on blood RNA samples comparing matUPD7, patUPD7, and controls showed differential expression for three genes with novel DMRs, HOXA4, GLI3, and SVOPL. Allele specific expression analysis confirmed maternal only expression of SVOPL and imprinting of HOXA4 was supported by monoallelic expression. These results present the first comprehensive map of parent-of-origin specific DMRs on human chromosome 7, suggesting many new imprinted sites.
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Affiliation(s)
- Katariina Hannula-Jouppi
- Department of Medical Genetics; Haartman Institute; Molecular Neurology Program; Research Program's Unit; Folkhälsan Institute of Genetics; University of Helsinki; Helsinki, Finland; Department of Dermatology and Allergology; Skin and Allergy Hospital; Helsinki University Central Hospital; Helsinki University Hospital; Helsinki, Finland
| | - Mari Muurinen
- Department of Medical Genetics; Haartman Institute; Molecular Neurology Program; Research Program's Unit; Folkhälsan Institute of Genetics; University of Helsinki; Helsinki, Finland
| | - Marita Lipsanen-Nyman
- Children's Hospital; University of Helsinki and Helsinki University Central Hospital; Helsinki University Hospital; Helsinki, Finland
| | - Lovisa E Reinius
- Department of Biosciences and Nutrition; Center for Biosciences; Karolinska Institutet; Stockholm, Sweden
| | - Sini Ezer
- Department of Medical Genetics; Haartman Institute; Molecular Neurology Program; Research Program's Unit; Folkhälsan Institute of Genetics; University of Helsinki; Helsinki, Finland
| | - Dario Greco
- Department of Medical Genetics; Haartman Institute; Molecular Neurology Program; Research Program's Unit; Folkhälsan Institute of Genetics; University of Helsinki; Helsinki, Finland; Department of Biosciences and Nutrition; Center for Biosciences; Karolinska Institutet; Stockholm, Sweden; Unit of Systems Toxicology; Finnish Institute of Occupational Health (FIOH); Helsinki, Finland
| | - Juha Kere
- Department of Medical Genetics; Haartman Institute; Molecular Neurology Program; Research Program's Unit; Folkhälsan Institute of Genetics; University of Helsinki; Helsinki, Finland; Department of Biosciences and Nutrition; Center for Biosciences; Karolinska Institutet; Stockholm, Sweden; Science for Life Laboratory; Karolinska Institutet; Solna, Sweden
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19
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Human RNAi pathway: crosstalk with organelles and cells. Funct Integr Genomics 2013; 14:31-46. [PMID: 24197738 DOI: 10.1007/s10142-013-0344-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 10/03/2013] [Accepted: 10/07/2013] [Indexed: 12/12/2022]
Abstract
Understanding gene regulation mechanisms has been a serious challenge in biology. As a novel mechanism, small non-coding RNAs are an alternative means of gene regulation in a specific and efficient manner. There are growing reports on regulatory roles of these RNAs including transcriptional gene silencing/activation and post-transcriptional gene silencing events. Also, there are several known small non-coding RNAs which all work through RNA interference pathway. Interestingly, these small RNAs are secreted from cells toward targeted cells presenting new communication approach in cell-cell or cell-organ signal transduction. In fact, understanding cellular and molecular basis of these pathways will strongly improve developing targeted therapies and potent and specific regulatory tools. This study will review some of the most recent findings in this subject and will introduce a super-pathway RNA interference-based small RNA silencing network.
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Abstract
The past two decades have seen an explosion in research on non-coding RNAs and their physiological and pathological functions. Several classes of small (20-30 nucleotides) and long (>200 nucleotides) non-coding RNAs have been firmly established as key regulators of gene expression in myriad processes ranging from embryonic development to innate immunity. In this review, we focus on our current understanding of the molecular mechanisms underlying the biogenesis and function of small interfering RNAs (siRNAs), microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs). In addition, we briefly review the relevance of small and long non-coding RNAs to human physiology and pathology and their potential to be exploited as therapeutic agents.
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Affiliation(s)
- Veena S Patil
- Program for RNA Biology, Sanford-Burnham Medical Research Institute , La Jolla, CA , USA
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21
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Zhang M, Xie S, Dong X, Zhao X, Zeng B, Chen J, Li H, Yang W, Zhao H, Wang G, Chen Z, Sun S, Hauck A, Jin W, Lai J. Genome-wide high resolution parental-specific DNA and histone methylation maps uncover patterns of imprinting regulation in maize. Genome Res 2013; 24:167-76. [PMID: 24131563 PMCID: PMC3875858 DOI: 10.1101/gr.155879.113] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Genetic imprinting is a specific epigenetic phenomenon in which a subset of genes is expressed depending on their parent-of-origin. Two types of chromatin modifications, DNA methylation and histone modification, are generally believed to be involved in the regulation of imprinting. However, the genome-wide correlation between allele-specific chromatin modifications and imprinted gene expression in maize remains elusive. Here we report genome-wide high resolution allele-specific maps of DNA methylation and histone H3 lysine 27 trimethylation (H3K27me3) in maize endosperm. For DNA methylation, thousands of parent-of-origin dependent differentially methylated regions (pDMRs) were identified. All pDMRs were uniformly paternally hypermethylated and maternally hypomethylated. We also identified 1131 allele-specific H3K27me3 peaks that are preferentially present in the maternal alleles. Maternally expressed imprinted genes (MEGs) and paternally expressed imprinted genes (PEGs) had different patterns of allele-specific DNA methylation and H3K27me3. Allele-specific expression of MEGs was not directly related to allele-specific H3K27me3, and only a subset of MEGs was associated with maternal-specific DNA demethylation, which was primarily located in the upstream and 5' portion of gene body regions. In contrast, allele-specific expression of a majority of PEGs was related to maternal-specific H3K27me3, with a subgroup of PEGs also associated with maternal-specific DNA demethylation. Both pDMRs and maternal H3K27me3 peaks associated with PEGs are enriched in gene body regions. Our results indicate highly complex patterns of regulation on genetic imprinting in maize endosperm.
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Affiliation(s)
- Mei Zhang
- State Key Laboratory of Agrobiotechnology and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
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22
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Garitano-Trojaola A, Agirre X, Prósper F, Fortes P. Long non-coding RNAs in haematological malignancies. Int J Mol Sci 2013; 14:15386-422. [PMID: 23887658 PMCID: PMC3759866 DOI: 10.3390/ijms140815386] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 06/28/2013] [Accepted: 07/09/2013] [Indexed: 12/20/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) are functional RNAs longer than 200 nucleotides in length. LncRNAs are as diverse as mRNAs and they normally share the same biosynthetic machinery based on RNA polymerase II, splicing and polyadenylation. However, lncRNAs have low coding potential. Compared to mRNAs, lncRNAs are preferentially nuclear, more tissue specific and expressed at lower levels. Most of the lncRNAs described to date modulate the expression of specific genes by guiding chromatin remodelling factors; inducing chromosomal loopings; affecting transcription, splicing, translation or mRNA stability; or serving as scaffolds for the organization of cellular structures. They can function in cis, cotranscriptionally, or in trans, acting as decoys, scaffolds or guides. These functions seem essential to allow cell differentiation and growth. In fact, many lncRNAs have been shown to exert oncogenic or tumor suppressor properties in several cancers including haematological malignancies. In this review, we summarize what is known about lncRNAs, the mechanisms for their regulation in cancer and their role in leukemogenesis, lymphomagenesis and hematopoiesis. Furthermore, we discuss the potential of lncRNAs in diagnosis, prognosis and therapy in cancer, with special attention to haematological malignancies.
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Affiliation(s)
- Andoni Garitano-Trojaola
- Laboratory of Myeloproliferative Syndromes, Oncology Area, Foundation for Applied Medical Research, University of Navarra, Pamplona 31008, Spain; E-Mails: (A.G.-T.); (X.A.); (F.P.)
| | - Xabier Agirre
- Laboratory of Myeloproliferative Syndromes, Oncology Area, Foundation for Applied Medical Research, University of Navarra, Pamplona 31008, Spain; E-Mails: (A.G.-T.); (X.A.); (F.P.)
| | - Felipe Prósper
- Laboratory of Myeloproliferative Syndromes, Oncology Area, Foundation for Applied Medical Research, University of Navarra, Pamplona 31008, Spain; E-Mails: (A.G.-T.); (X.A.); (F.P.)
- Hematology Service and Area of Cell Therapy, University of Navarra Clinic, University of Navarra, Pamplona 31008, Spain
| | - Puri Fortes
- Department of Hepatology and Gene Therapy, Foundation for Applied Medical Research, University of Navarra, Pamplona 31008, Spain
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23
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Transgene- and locus-dependent imprinting reveals allele-specific chromosome conformations. Proc Natl Acad Sci U S A 2013; 110:11946-51. [PMID: 23818637 DOI: 10.1073/pnas.1310704110] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
When positioned into the integrin α-6 gene, an Hoxd9lacZ reporter transgene displayed parental imprinting in mouse embryos. While the expression from the paternal allele was comparable with patterns seen for the same transgene when present at the neighboring HoxD locus, almost no signal was scored at this integration site when the transgene was inherited from the mother, although the Itga6 locus itself is not imprinted. The transgene exhibited maternal allele-specific DNA hypermethylation acquired during oogenesis, and its expression silencing was reversible on passage through the male germ line. Histone modifications also corresponded to profiles described at known imprinted loci. Chromosome conformation analyses revealed distinct chromatin microarchitectures, with a more compact structure characterizing the maternally inherited repressed allele. Such genetic analyses of well-characterized transgene insertions associated with a de novo-induced parental imprint may help us understand the molecular determinants of imprinting.
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Kornienko AE, Guenzl PM, Barlow DP, Pauler FM. Gene regulation by the act of long non-coding RNA transcription. BMC Biol 2013; 11:59. [PMID: 23721193 PMCID: PMC3668284 DOI: 10.1186/1741-7007-11-59] [Citation(s) in RCA: 549] [Impact Index Per Article: 49.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 05/15/2013] [Indexed: 12/20/2022] Open
Abstract
Long non-protein-coding RNAs (lncRNAs) are proposed to be the largest transcript class in the mouse and human transcriptomes. Two important questions are whether all lncRNAs are functional and how they could exert a function. Several lncRNAs have been shown to function through their product, but this is not the only possible mode of action. In this review we focus on a role for the process of lncRNA transcription, independent of the lncRNA product, in regulating protein-coding-gene activity in cis. We discuss examples where lncRNA transcription leads to gene silencing or activation, and describe strategies to determine if the lncRNA product or its transcription causes the regulatory effect.
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Affiliation(s)
- Aleksandra E Kornienko
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH-BT25,3, 1090, Vienna, Austria
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25
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Santoro F, Pauler FM. Silencing by the imprinted Airn macro lncRNA: transcription is the answer. Cell Cycle 2013; 12:711-2. [PMID: 23422859 PMCID: PMC3610713 DOI: 10.4161/cc.23860] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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26
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Knauss JL, Sun T. Regulatory mechanisms of long noncoding RNAs in vertebrate central nervous system development and function. Neuroscience 2013; 235:200-14. [PMID: 23337534 DOI: 10.1016/j.neuroscience.2013.01.022] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/28/2012] [Accepted: 01/09/2013] [Indexed: 01/22/2023]
Abstract
Long noncoding RNAs (lncRNAs) have emerged as an important class of molecules that regulate gene expression at epigenetic, transcriptional, and post-transcriptional levels through a wide array of mechanisms. This regulation is of particular importance in the central nervous system (CNS), where precise modulation of gene expression is required for proper neuronal and glial production, connection and function. There are relatively few functional studies that characterize lncRNA mechanisms, but possible functions can often be inferred based on existing examples and the lncRNA's relative genomic position. In this review, we will discuss mechanisms of lncRNAs as predicted by genomic contexts and the possible impact on CNS development, function, and disease pathogenesis. There is no doubt that investigation of the mechanistic role of lncRNAs will open a new and exciting direction in studying CNS development and function.
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Affiliation(s)
- J L Knauss
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, New York, NY, United States.
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27
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Dhanasekaran K, Kumari S, Kanduri C. Noncoding RNAs in chromatin organization and transcription regulation: an epigenetic view. Subcell Biochem 2013; 61:343-72. [PMID: 23150258 DOI: 10.1007/978-94-007-4525-4_15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The Genome of a eukaryotic cell harbors genetic material in the form of DNA which carries the hereditary information encoded in their bases. Nucleotide bases of DNA are transcribed into complimentary RNA bases which are further translated into protein, performing defined set of functions. The central dogma of life ensures sequential flow of genetic information among these biopolymers. Noncoding RNAs (ncRNAs) serve as exceptions for this principle as they do not code for any protein. Nevertheless, a major portion of the human transcriptome comprises noncoding RNAs. These RNAs vary in size, as well as they vary in the spatio-temporal distribution. These ncRnAs are functional and are shown to be involved in diverse cellular activities. Precise location and expression of ncRNA is essential for the cellular homeostasis. Failures of these events ultimately results in numerous disease conditions including cancer. The present review lists out the various classes of ncRNAs with a special emphasis on their role in chromatin organization and transcription regulation.
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Affiliation(s)
- Karthigeyan Dhanasekaran
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India
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28
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Abstract
Genomic imprinting is an epigenetic phenomenon in which either the paternal or the maternal allele of imprinted genes is expressed in somatic cells. It is unique to eutherian mammals, marsupials, and flowering plants. It is absolutely required for normal mammalian development. Dysregulation of genomic imprinting can cause a variety of human diseases. About 150 imprinted genes have been identified so far in mammals and many of them are clustered such that they are coregulated by a cis-acting imprinting control region, called the ICR. One hallmark of the ICR is that it contains a germ line-derived differentially methylated region that is methylated on the paternal chromosome or on the maternal chromosome. The DNA methylation imprint is reset in the germ line and differential methylation at an ICR is restored upon fertilization. The DNA methylation imprint is resistant to a genome-wide demethylation process in early embryos and is stably maintained in postimplantation embryos. Maintenance of the DNA methylation imprint is dependent on two distinct maternal effect genes (Zfp57 and PGC7/Stella). In germ cells, around midgestation, the DNA methylation imprint is erased and undergoes another round of the DNA methylation imprint cycle that includes erasure, resetting, restoration, and maintenance of differential DNA methylation.
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Affiliation(s)
- Xiajun Li
- Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, USA.
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29
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Abstract
Recent studies show that transcription of the mammalian genome is not only pervasive but also enormously complex. It is estimated that an average of 10 transcription units, the vast majority of which make long noncoding RNAs (lncRNAs), may overlap each traditional coding gene. These lncRNAs include not only antisense, intronic, and intergenic transcripts but also pseudogenes and retrotransposons. Do they universally have function, or are they merely transcriptional by-products of conventional coding genes? A glimpse into the molecular biology of multiple emerging lncRNA systems reveals the "Wild West" landscape of their functions and mechanisms and the key problems to solve in the years ahead toward understanding these intriguing macromolecules.
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Affiliation(s)
- Jeannie T Lee
- Howard Hughes Medical Institute, Department of Molecular Biology, Massachusetts General Hospital, and Department of Genetics, Harvard Medical School, Boston, MA 02138, USA.
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30
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Abstract
The discovery of numerous noncoding RNA (ncRNA) transcripts in species from yeast to mammals has dramatically altered our understanding of cell biology, especially the biology of diseases such as cancer. In humans, the identification of abundant long ncRNA (lncRNA) >200 bp has catalyzed their characterization as critical components of cancer biology. Recently, roles for lncRNAs as drivers of tumor suppressive and oncogenic functions have appeared in prevalent cancer types, such as breast and prostate cancer. In this review, we highlight the emerging impact of ncRNAs in cancer research, with a particular focus on the mechanisms and functions of lncRNAs.
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Affiliation(s)
- John R Prensner
- Michigan Center for Translational Pathology, Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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31
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Duart-Garcia C, Braunschweig MH. The Igf2as transcript is exported into cytoplasm and associated with polysomes. Biochem Genet 2012; 51:119-30. [PMID: 23108799 DOI: 10.1007/s10528-012-9547-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 09/12/2012] [Indexed: 11/27/2022]
Abstract
Murine insulin-like growth factor 2 antisense (Igf2as) transcripts originate from the opposite strand of the same Igf2 locus as the Igf2 sense mRNA. The Igf2, insulin 2 (Ins2), and H19 genes form a cluster of imprinted genes on chromosome 7. Loss of imprinting of IGF2 in humans is associated with Beckwith-Wiedemann syndrome and Silver-Russell syndrome, as well as with Wilm's tumor and colorectal cancer. We developed a RNA-FISH protocol to detect Igf2as and Igf2 transcripts. The results from the RNA-FISH were confirmed with quantitative real-time PCR and clearly indicate that the Igf2as transcripts are predominantly located in the cytoplasm of C2C12 cells. In a polysome association study, we showed that the Igf2as sedimented with polysomes in a sucrose gradient. The cellular localization of Igf2as transcripts together with polysome fractionation analysis provides compelling evidence that the Igf2as is protein coding.
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Affiliation(s)
- Carolina Duart-Garcia
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3001, Berne, Switzerland
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32
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Korostowski L, Sedlak N, Engel N. The Kcnq1ot1 long non-coding RNA affects chromatin conformation and expression of Kcnq1, but does not regulate its imprinting in the developing heart. PLoS Genet 2012; 8:e1002956. [PMID: 23028363 PMCID: PMC3447949 DOI: 10.1371/journal.pgen.1002956] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 08/01/2012] [Indexed: 12/22/2022] Open
Abstract
Although many of the questions raised by the discovery of imprinting have been answered, we have not yet accounted for tissue- or stage-specific imprinting. The Kcnq1 imprinted domain exhibits complex tissue-specific expression patterns co-existing with a domain-wide cis-acting control element. Transcription of the paternally expressed antisense non-coding RNA Kcnq1ot1 silences some neighboring genes in the embryo, while others are unaffected. Kcnq1 is imprinted in early cardiac development but becomes biallelic after midgestation. To explore this phenomenon and the role of Kcnq1ot1, we used allele-specific assays and chromosome conformational studies in wild-type mice and mice with a premature termination mutation for Kcnq1ot1. We show that Kcnq1 imprinting in early heart is established and maintained independently of Kcnq1ot1 expression, thus excluding a role for Kcnq1ot1 in repressing Kcnq1, even while silencing other genes in the domain. The exact timing of the mono- to biallelic transition is strain-dependent, with the CAST/EiJ allele becoming activated earlier and acquiring higher levels than the C57BL/6J allele. Unexpectedly, Kcnq1ot1 itself also switches to biallelic expression specifically in the heart, suggesting that tissue-specific loss of imprinting may be common during embryogenesis. The maternal Kcnq1ot1 transcript is shorter than the paternal ncRNA, and its activation depends on an alternative transcriptional start site that bypasses the maternally methylated promoter. Production of Kcnq1ot1 on the maternal chromosome does not silence Cdkn1c. We find that in later developmental stages, however, Kcnq1ot1 has a role in modulating Kcnq1 levels, since its absence leads to overexpression of Kcnq1, an event accompanied by an aberrant three-dimensional structure of the chromatin. Thus, our studies reveal regulatory mechanisms within the Kcnq1 imprinted domain that operate exclusively in the heart on Kcnq1, a gene crucial for heart development and function. We also uncover a novel mechanism by which an antisense non-coding RNA affects transcription through regulating chromatin flexibility and access to enhancers.
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Affiliation(s)
| | | | - Nora Engel
- Fels Institute for Cancer Research/Biochemistry, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
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33
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Long non-coding RNA in epigenetic gene silencing. Epigenomics 2012. [DOI: 10.1017/cbo9780511777271.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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34
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Guenzl PM, Barlow DP. Macro lncRNAs: a new layer of cis-regulatory information in the mammalian genome. RNA Biol 2012; 9:731-41. [PMID: 22617879 DOI: 10.4161/rna.19985] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In the past ten years, long non-protein-coding RNAs (lncRNAs) have been shown to comprise a major part of the mammalian transcriptome and are predicted from their highly specific expression patterns, to play a role in regulating protein-coding gene expression in development and disease. Many lncRNAs particularly those lying in imprinted clusters, are predominantly unspliced "macro" transcripts that can also show a low level of splicing, and both the unspliced and spliced transcript have the potential to be functional. Three known imprinted macro lncRNAs have been shown to silence from three to ten genes in cis in imprinted gene clusters. We review here the potential for functional macro lncRNAs, defined here as "inefficiently-spliced lncRNAs" to play a wider cis-regulatory role in the mammalian genome. This potential has been underestimated by the inability of current RNA-seq technology to annotate unspliced macro lncRNAs.
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Affiliation(s)
- Philipp M Guenzl
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH-BT25.3, Vienna 1090, Austria
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35
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Abstract
Antisense RNA is the first noncoding RNA found to have a regulatory function. With the advances of biological science, it has been recognized that the function of antisense RNAs is not only limited to post-transcriptional regulation, but extends to transcriptional regulation of various important genes leading to epigenetic changes in DNA methylation and histone modifications. Gene regulation by antisense RNA is a general phenomenon observed in eukaryotic cells while genome-wide natural antisense transcripts have been identified in many animals and plants. Antisense RNAs are not only involved in X-chromosome inactivation and imprinted silencing in normal cells, but aberrantly expressed antisense RNAs can also induce epigenetic silencing of tumor suppressor genes in cancer cells and deletion-induced aberrant antisense RNAs lead to epigenetic silencing and diseases. While a general picture of the pathways involved in antisense RNA-mediated gene regulation has emerged, many questions remain. The mechanisms by which genes are regulated by antisense RNAs, antisense transcript itself is produced and aberrant antisense RNAs induce human diseases are all research focuses of the future.
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36
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Meng L, Person RE, Beaudet AL. Ube3a-ATS is an atypical RNA polymerase II transcript that represses the paternal expression of Ube3a. Hum Mol Genet 2012; 21:3001-12. [PMID: 22493002 DOI: 10.1093/hmg/dds130] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Angelman syndrome gene, UBE3A, is subject to genomic imprinting controlled by mechanisms that are only partially understood. Its antisense transcript, UBE3A-ATS, is also imprinted and hypothesized to suppress UBE3A in cis. In this research, we showed that the mouse antisense ortholog, Ube3a-ATS, was transcribed by RNA polymerase (RNAP) II. However, unlike typical protein-coding transcripts, Ube3a-ATS was not poly-adenylated and was localized exclusively in the nucleus. It was relatively unstable with a half-life of 4 h, shorter than most protein-coding RNAs tested. To understand the role of Ube3a-ATS in vivo, a mouse model with a 0.9-kb genomic deletion over the paternal Snrpn major promoter was studied. The mice showed partial activation of paternal Ube3a, with decreased expression of Ube3a-ATS but not any imprinting defects in the Prader-Willi syndrome/Angelman syndrome region. A novel cell culture model was also generated with a transcriptional termination cassette inserted downstream of Ube3a on the paternal chromosome to reduce Ube3a-ATS transcription. In neuronally differentiated embryonic stem (ES) cells, paternal Ube3a was found to be expressed at a high level, comparable with that of the maternal allele. To further characterize the antisense RNA, a strand-specific microarray was performed. Ube3a-ATS was detectable across the entire locus of Ube3a and extended beyond the transcriptional start site of Ube3a. In summary, we conclude that Ube3a-ATS is an atypical RNAPII transcript that represses Ube3a on the paternal chromosome. These results suggest that the repression of human UBE3A-ATS may activate the expression of UBE3A from the paternal chromosome, providing a potential therapeutic strategy for patients with Angelman syndrome.
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Affiliation(s)
- Linyan Meng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
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37
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Pauler FM, Barlow DP, Hudson QJ. Mechanisms of long range silencing by imprinted macro non-coding RNAs. Curr Opin Genet Dev 2012; 22:283-9. [PMID: 22386265 PMCID: PMC3387373 DOI: 10.1016/j.gde.2012.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 02/07/2012] [Accepted: 02/07/2012] [Indexed: 12/21/2022]
Abstract
Non-coding (nc) RNA silencing of imprinted genes in extra-embryonic tissues provides a good model for understanding an underexamined aspect of gene regulation by macro or long ncRNAs, that is their action as long-range cis-silencers. Numerous long intergenic ncRNAs (lincRNAs) have been recently discovered that are thought to regulate gene expression, some of which have been associated with disease. The few shown to regulate protein-coding genes are suggested to act by targeting repressive or active chromatin marks. Correlative evidence also indicates that imprinted macro ncRNAs cause long-range cis-silencing in placenta by targeting repressive histone modifications to imprinted promoters. It is timely, however, to consider alternative explanations consistent with the published data, whereby transcription alone could cause gene silencing at a distance.
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Affiliation(s)
- Florian M Pauler
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Science, Lazarettgasse 14, AKH-BT 25.3, 1090 Vienna, Austria
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38
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Koerner MV, Pauler FM, Hudson QJ, Santoro F, Sawicka A, Guenzl PM, Stricker SH, Schichl YM, Latos PA, Klement RM, Warczok KE, Wojciechowski J, Seiser C, Kralovics R, Barlow DP. A downstream CpG island controls transcript initiation and elongation and the methylation state of the imprinted Airn macro ncRNA promoter. PLoS Genet 2012; 8:e1002540. [PMID: 22396659 PMCID: PMC3291542 DOI: 10.1371/journal.pgen.1002540] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 12/29/2011] [Indexed: 11/18/2022] Open
Abstract
A CpG island (CGI) lies at the 5' end of the Airn macro non-protein-coding (nc) RNA that represses the flanking Igf2r promoter in cis on paternally inherited chromosomes. In addition to being modified on maternally inherited chromosomes by a DNA methylation imprint, the Airn CGI shows two unusual organization features: its position immediately downstream of the Airn promoter and transcription start site and a series of tandem direct repeats (TDRs) occupying its second half. The physical separation of the Airn promoter from the CGI provides a model to investigate if the CGI plays distinct transcriptional and epigenetic roles. We used homologous recombination to generate embryonic stem cells carrying deletions at the endogenous locus of the entire CGI or just the TDRs. The deleted Airn alleles were analyzed by using an ES cell imprinting model that recapitulates the onset of Igf2r imprinted expression in embryonic development or by using knock-out mice. The results show that the CGI is required for efficient Airn initiation and to maintain the unmethylated state of the Airn promoter, which are both necessary for Igf2r repression on the paternal chromosome. The TDRs occupying the second half of the CGI play a minor role in Airn transcriptional elongation or processivity, but are essential for methylation on the maternal Airn promoter that is necessary for Igf2r to be expressed from this chromosome. Together the data indicate the existence of a class of regulatory CGIs in the mammalian genome that act downstream of the promoter and transcription start.
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Affiliation(s)
- Martha V. Koerner
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Florian M. Pauler
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Quanah J. Hudson
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Federica Santoro
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Anna Sawicka
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna, Austria
| | - Philipp M. Guenzl
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Stefan H. Stricker
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Yvonne M. Schichl
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Paulina A. Latos
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Ruth M. Klement
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Katarzyna E. Warczok
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Jacek Wojciechowski
- IMP/IMBA Transgenic Service, Research Institute of Molecular Pathology, Vienna, Austria
| | - Christian Seiser
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna, Austria
| | - Robert Kralovics
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Denise P. Barlow
- CeMM–Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- * E-mail:
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39
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Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation. Asian J Androl 2012; 14:436-50. [PMID: 22367183 DOI: 10.1038/aja.2011.160] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 (EZH2) overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 (IGF2). A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.
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40
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Affiliation(s)
- Denise P. Barlow
- CeMM, Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria;
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41
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Extensive, clustered parental imprinting of protein-coding and noncoding RNAs in developing maize endosperm. Proc Natl Acad Sci U S A 2011; 108:20042-7. [PMID: 22114195 DOI: 10.1073/pnas.1112186108] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although genetic imprinting was discovered in maize 40 years ago, its exact extent in the triploid endosperm remains unknown. Here, we have analyzed global patterns of allelic gene expression in developing maize endosperms from reciprocal crosses between inbreds B73 and Mo17. We have defined an imprinted gene as one in which the relative expression of the maternal and paternal alleles differ at least fivefold in both hybrids of the reciprocal crosses. We found that at least 179 genes (1.6% of protein-coding genes) expressed in the endosperm are imprinted, with 68 of them showing maternal preferential expression and 111 paternal preferential expression. Additionally, 38 long noncoding RNAs were imprinted. The latter are transcribed in either sense or antisense orientation from intronic regions of normal protein-coding genes or from intergenic regions. Imprinted genes show a clear pattern of clustering around the genome, with a number of imprinted genes being adjacent to each other. Analysis of allele-specific methylation patterns of imprinted loci in the hybrid endosperm identified 21 differentially methylated regions (DMRs) of several hundred base pairs in length, corresponding to both imprinted genes and noncoding transcripts. All DMRs identified are uniformly hypomethylated in maternal alleles and hypermethylated in paternal alleles, regardless of the imprinting direction of their corresponding loci. Our study indicates highly extensive and complex regulation of genetic imprinting in maize endosperm, a mechanism that can potentially function in the balancing of the gene dosage of this triploid tissue.
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42
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Zaratiegui M, Castel SE, Irvine DV, Kloc A, Ren J, Li F, de Castro E, Marín L, Chang AY, Goto D, Cande WZ, Antequera F, Arcangioli B, Martienssen RA. RNAi promotes heterochromatic silencing through replication-coupled release of RNA Pol II. Nature 2011; 479:135-8. [PMID: 22002604 PMCID: PMC3391703 DOI: 10.1038/nature10501] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 08/25/2011] [Indexed: 11/25/2022]
Abstract
Heterochromatin comprises tightly compacted repetitive regions of eukaryotic chromosomes. The inheritance of heterochromatin through mitosis requires RNA interference (RNAi), which guides histone modification 1 during the DNA replication phase of the cell cycle2. Here, we show that the alternating arrangement of origins of replication and non-coding RNA in pericentromeric heterochromatin results in competition between transcription and replication. Co-transcriptional RNAi releases RNA polymerase II (PolII), allowing completion of DNA replication by the leading strand DNA polymerase, and associated histone modifying enzymes3 which spread heterochromatin with the replication fork. In the absence of RNAi, stalled forks are repaired by homologous recombination without histone modification.
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Affiliation(s)
- Mikel Zaratiegui
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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43
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Saxena A, Carninci P. Long non-coding RNA modifies chromatin: epigenetic silencing by long non-coding RNAs. Bioessays 2011; 33:830-9. [PMID: 21915889 PMCID: PMC3258546 DOI: 10.1002/bies.201100084] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/09/2011] [Accepted: 08/10/2011] [Indexed: 12/16/2022]
Abstract
Common themes are emerging in the molecular mechanisms of long non-coding RNA-mediated gene repression. Long non-coding RNAs (lncRNAs) participate in targeted gene silencing through chromatin remodelling, nuclear reorganisation, formation of a silencing domain and precise control over the entry of genes into silent compartments. The similarities suggest that these are fundamental processes of transcription regulation governed by lncRNAs. These findings have paved the way for analogous investigations on other lncRNAs and chromatin remodelling enzymes. Here we discuss these common mechanisms and provide our view on other molecules that warrant similar investigations. We also present our concepts on the possible mechanisms that may facilitate the exit of genes from the silencing domains and their potential therapeutic applications. Finally, we point to future areas of research and put forward our recommendations for improvements in resources and applications of existing technologies towards targeted outcomes in this active area of research.
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Affiliation(s)
- Alka Saxena
- Omics Science Center, RIKEN Yokohama Institute, 1-7-22 Suehiro Cho, Tsurumi Ku, Yokohama, Kanagawa 230-0045, Japan
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44
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Golding MC, Magri LS, Zhang L, Lalone SA, Higgins MJ, Mann MRW. Depletion of Kcnq1ot1 non-coding RNA does not affect imprinting maintenance in stem cells. Development 2011; 138:3667-78. [PMID: 21775415 PMCID: PMC3152924 DOI: 10.1242/dev.057778] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2011] [Indexed: 01/18/2023]
Abstract
To understand the complex regulation of genomic imprinting it is important to determine how early embryos establish imprinted gene expression across large chromosomal domains. Long non-coding RNAs (ncRNAs) have been associated with the regulation of imprinting domains, yet their function remains undefined. Here, we investigated the mouse Kcnq1ot1 ncRNA and its role in imprinted gene regulation during preimplantation development by utilizing mouse embryonic and extra-embryonic stem cell models. Our findings demonstrate that the Kcnq1ot1 ncRNA extends 471 kb from the transcription start site. This is significant as it raises the possibility that transcription through downstream genes might play a role in their silencing, including Th, which we demonstrate possesses maternal-specific expression during early development. To distinguish between a functional role for the transcript and properties inherent to transcription of long ncRNAs, we employed RNA interference-based technology to deplete Kcnq1ot1 transcripts. We hypothesized that post-transcriptional depletion of Kcnq1ot1 ncRNA would lead to activation of normally maternal-specific protein-coding genes on the paternal chromosome. Post-transcriptional short hairpin RNA-mediated depletion in embryonic stem, trophoblast stem and extra-embryonic endoderm stem cells had no observable effect on the imprinted expression of genes within the domain, or on Kcnq1ot1 imprinting center DNA methylation, although a significant decrease in Kcnq1ot1 RNA signal volume in the nucleus was observed. These data support the argument that it is the act of transcription that plays a role in imprint maintenance during early development rather than a post-transcriptional role for the RNA itself.
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Affiliation(s)
- Michael C. Golding
- Departments of Obstetrics and Gynecology and Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, ON N6A 5W9, Canada
- Children's Health Research Institute, London, ON N6C 2V5, Canada
- Lawson Health Research Institute, London, ON N6C 2V5, Canada
| | - Lauren S. Magri
- Departments of Obstetrics and Gynecology and Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, ON N6A 5W9, Canada
- Children's Health Research Institute, London, ON N6C 2V5, Canada
- Lawson Health Research Institute, London, ON N6C 2V5, Canada
| | - Liyue Zhang
- Children's Health Research Institute, London, ON N6C 2V5, Canada
- Lawson Health Research Institute, London, ON N6C 2V5, Canada
| | - Sarah A. Lalone
- Departments of Obstetrics and Gynecology and Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, ON N6A 5W9, Canada
- Children's Health Research Institute, London, ON N6C 2V5, Canada
- Lawson Health Research Institute, London, ON N6C 2V5, Canada
| | - Michael J. Higgins
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Mellissa R. W. Mann
- Departments of Obstetrics and Gynecology and Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, ON N6A 5W9, Canada
- Children's Health Research Institute, London, ON N6C 2V5, Canada
- Lawson Health Research Institute, London, ON N6C 2V5, Canada
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45
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Wutz A. RNA-mediated silencing mechanisms in mammalian cells. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 101:351-76. [PMID: 21507358 DOI: 10.1016/b978-0-12-387685-0.00011-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Noncoding RNAs are a structural component of the nuclear scaffold and have been implicated in controlling gene expression. In mammals, long noncoding RNAs contribute to the regulation of imprinted gene expression, dosage compensation, development, and tumorigenesis. RNA is also a component of pericentric heterochromatin, and transcripts have been identified at the chromosomal telomeres. The functions of noncoding RNAs are likely diverse, and their underlying mechanisms are just beginning to be understood. Several noncoding RNAs interact with chromatin-modifying complexes and might have a role in targeting chromatin modifications to specific regions of the genome. This suggests a prominent function of RNA in establishing histone modification and DNA methylation patterns in development. Studies on model systems such as X inactivation, the regulation of the Hox clusters, and genomic imprinting have begun to shed light on the role of noncoding RNAs in chromosomal organization and regulation of gene expression. Well-studied examples of noncoding RNAs include Xist, Air, Kcnq1ot1, HOTAIR, and Tsix. Here, a concise review of noncoding RNA function in mammals is given, and the present understanding and future directions of the field are summarized.
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Affiliation(s)
- Anton Wutz
- Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Cambridge, United Kingdom
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46
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Noncoding RNAs and enhancers: complications of a long-distance relationship. Trends Genet 2011; 27:433-9. [PMID: 21831473 DOI: 10.1016/j.tig.2011.06.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 06/22/2011] [Accepted: 06/22/2011] [Indexed: 01/30/2023]
Abstract
Spatial and temporal regulation of gene expression is achieved through instructions provided by the distal transcriptional regulatory elements known as enhancers. How enhancers transmit such information to their targets has been the subject of intense investigation. Recent advances in high throughput analysis of the mammalian transcriptome have revealed a surprising result indicating that a large number of enhancers are transcribed to noncoding RNAs. Although long noncoding RNAs were initially shown to confer epigenetic transcriptional repression, recent studies have uncovered a role for a class of such transcripts in gene-specific activation, often from distal genomic regions. In this review, we discuss recent findings on the role of long noncoding RNAs in transcriptional regulation, with an emphasis on new developments on the functional links between long noncoding RNAs and enhancers.
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Kageyama Y, Kondo T, Hashimoto Y. Coding vs non-coding: Translatability of short ORFs found in putative non-coding transcripts. Biochimie 2011; 93:1981-6. [PMID: 21729735 DOI: 10.1016/j.biochi.2011.06.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/20/2011] [Indexed: 01/13/2023]
Abstract
Genome analysis has identified a number of putative non-protein-coding transcripts that do not contain ORFs longer than 100 codons. Although evidence strongly suggests that non-coding RNAs are important in a variety of biological phenomena, the discovery of small peptide-coding mRNAs confirms that some transcripts that have been assumed to be non-coding actually have coding potential. Their abundance and importance in biological phenomena makes the sorting of non-coding RNAs from small peptide-coding mRNAs a key issue in functional genomics. However, validating the coding potential of small peptide-coding RNAs is complicated, because their ORF sequences are usually too short for computational analysis. In this review, we discuss computational and experimental methods for validating the translatability of these non-coding RNAs.
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Affiliation(s)
- Yuji Kageyama
- Okazaki Institute for Integrated Biosciences, National Institutes of Natural Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi 444-8787, Japan.
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Woodwark C, Bateman A. The characterisation of three types of genes that overlie copy number variable regions. PLoS One 2011; 6:e14814. [PMID: 21637334 PMCID: PMC3102654 DOI: 10.1371/journal.pone.0014814] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 09/07/2010] [Indexed: 12/21/2022] Open
Abstract
Background Due to the increased accuracy of Copy Number Variable region (CNV) break point mapping, it is now possible to say with a reasonable degree of confidence whether a gene (i) falls entirely within a CNV; (ii) overlaps the CNV or (iii) actually contains the CNV. We classify these as type I, II and III CNV genes respectively. Principal Findings Here we show that although type I genes vary in copy number along with the CNV, most of these type I genes have the same expression levels as wild type copy numbers of the gene. These genes must, therefore, be under homeostatic dosage compensation control. Looking into possible mechanisms for the regulation of gene expression we found that type I genes have a significant paucity of genes regulated by miRNAs and are not significantly enriched for monoallelically expressed genes. Type III genes, on the other hand, have a significant excess of genes regulated by miRNAs and are enriched for genes that are monoallelically expressed. Significance Many diseases and genomic disorders are associated with CNVs so a better understanding of the different ways genes are associated with normal CNVs will help focus on candidate genes in genome wide association studies.
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Affiliation(s)
- Cara Woodwark
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom.
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Williamson CM, Ball ST, Dawson C, Mehta S, Beechey CV, Fray M, Teboul L, Dear TN, Kelsey G, Peters J. Uncoupling antisense-mediated silencing and DNA methylation in the imprinted Gnas cluster. PLoS Genet 2011; 7:e1001347. [PMID: 21455290 PMCID: PMC3063750 DOI: 10.1371/journal.pgen.1001347] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 02/18/2011] [Indexed: 11/18/2022] Open
Abstract
There is increasing evidence that non-coding macroRNAs are major elements for silencing imprinted genes, but their mechanism of action is poorly understood. Within the imprinted Gnas cluster on mouse chromosome 2, Nespas is a paternally expressed macroRNA that arises from an imprinting control region and runs antisense to Nesp, a paternally repressed protein coding transcript. Here we report a knock-in mouse allele that behaves as a Nespas hypomorph. The hypomorph mediates down-regulation of Nesp in cis through chromatin modification at the Nesp promoter but in the absence of somatic DNA methylation. Notably there is reduced demethylation of H3K4me3, sufficient for down-regulation of Nesp, but insufficient for DNA methylation; in addition, there is depletion of the H3K36me3 mark permissive for DNA methylation. We propose an order of events for the regulation of a somatic imprint on the wild-type allele whereby Nespas modulates demethylation of H3K4me3 resulting in repression of Nesp followed by DNA methylation. This study demonstrates that a non-coding antisense transcript or its transcription is associated with silencing an overlapping protein-coding gene by a mechanism independent of DNA methylation. These results have broad implications for understanding the hierarchy of events in epigenetic silencing by macroRNAs. Genomic imprinting is a process resulting in expression of genes according to parental origin. Some imprinted genes are expressed when paternally derived and others when maternally derived. Thus imprinted genes are monoallelically expressed and one copy has to be silenced. There is evidence that some long non-coding RNAs, acting in cis, have a role in silencing. We investigated the role of Nespas, a gene for a non-coding RNA that is only expressed from the paternally derived chromosome in the Gnas cluster and runs antisense to its sense counterpart, Nesp. Expression of Nespas is associated with silencing of Nesp and a repressive methylation mark on the Nesp DNA. We generated a Nespas mutant with reduced levels of activity and showed that it down-regulated its sense counterpart Nesp, in the absence of a DNA methylation mark, but in the presence of an altered chromatin mark. We conclude that Nespas can repress Nesp by a mechanism independent of DNA methylation, by modulating a chromatin mark.
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Affiliation(s)
- Christine M. Williamson
- Medical Research Council Mammalian Genetics Unit, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Simon T. Ball
- Medical Research Council Mammalian Genetics Unit, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Claire Dawson
- Laboratory of Developmental Genetics and Imprinting, The Babraham Institute, Cambridge, United Kingdom
| | - Stuti Mehta
- Medical Research Council Mammalian Genetics Unit, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Colin V. Beechey
- Medical Research Council Mammalian Genetics Unit, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Martin Fray
- Medical Research Council Mary Lyon Centre, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Lydia Teboul
- Medical Research Council Mary Lyon Centre, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - T. Neil Dear
- Medical Research Council Mary Lyon Centre, Harwell Science and Innovation Campus, Harwell, United Kingdom
| | - Gavin Kelsey
- Laboratory of Developmental Genetics and Imprinting, The Babraham Institute, Cambridge, United Kingdom
- Centre for Trophoblast Research, University of Cambridge, Cambridge, United Kingdom
| | - Jo Peters
- Medical Research Council Mammalian Genetics Unit, Harwell Science and Innovation Campus, Harwell, United Kingdom
- * E-mail:
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50
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Santoro F, Barlow DP. Developmental control of imprinted expression by macro non-coding RNAs. Semin Cell Dev Biol 2011; 22:328-35. [PMID: 21333747 DOI: 10.1016/j.semcdb.2011.02.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 02/11/2011] [Indexed: 01/22/2023]
Abstract
Genomic imprinting is a developmentally regulated epigenetic phenomenon. The majority of imprinted genes only show parent-of-origin specific expression in a subset of tissues or at defined developmental stages. In some cases, imprinted expression is controlled by an imprinted macro non-coding RNA (ncRNA) whose expression pattern and repressive activity does not necessarily correlate with that of the genes whose imprinted expression it controls. This suggests that developmentally regulated factors other than the macro ncRNA are involved in establishing or maintaining imprinted expression. Here, we review how macro ncRNAs control imprinted expression during development and differentiation and consider how this impacts on target choice in epigenetic therapy.
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Affiliation(s)
- Federica Santoro
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Science, Lazarettgasse 14, AKH-BT25.3, 1090 Vienna, Austria
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