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You Q, Gong Q, Han YQ, Pi R, Du YJ, Dong SZ. Role of miR-124 in the regulation of retinoic acid-induced Neuro-2A cell differentiation. Neural Regen Res 2020; 15:1133-1139. [PMID: 31823894 PMCID: PMC7034285 DOI: 10.4103/1673-5374.270417] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Retinoic acid can cause many types of cells, including mouse neuroblastoma Neuro-2A cells, to differentiate into neurons. However, it is still unknown whether microRNAs (miRNAs) play a role in this neuronal differentiation. To address this issue, real-time polymerase chain reaction assays were used to detect the expression of several differentiation-related miRNAs during the differentiation of retinoic acid-treated Neuro-2A cells. The results revealed that miR-124 and miR-9 were upregulated, while miR-125b was downregulated in retinoic acid-treated Neuro-2A cells. To identify the miRNA that may play a key role, miR-124 expression was regulated by transfection of miRNA mimics or inhibitors. Morphological analysis results showed that inhibition of miR-124 expression reversed the effects of retinoic acid on neurite outgrowth. Moreover, miR-124 overexpression alone caused Neuro-2A cells to differentiate into neurons, and its inhibitor could block this effect. These results suggest that miR-124 plays an important role in retinoic acid-induced differentiation of Neuro-2A cells.
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Affiliation(s)
- Qun You
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | - Qiang Gong
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | - Yu-Qiao Han
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | - Rou Pi
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | - Yi-Jie Du
- Department of Integrative Medicine, Huashan Hospital; Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Su-Zhen Dong
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
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2
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Wei ZJ, Fan BY, Liu Y, Ding H, Tang HS, Pan DY, Shi JX, Zheng PY, Shi HY, Wu H, Li A, Feng SQ. MicroRNA changes of bone marrow-derived mesenchymal stem cells differentiated into neuronal-like cells by Schwann cell-conditioned medium. Neural Regen Res 2019; 14:1462-1469. [PMID: 30964074 PMCID: PMC6524508 DOI: 10.4103/1673-5374.253532] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Bone marrow-derived mesenchymal stem cells differentiate into neurons under the induction of Schwann cells. However, key microRNAs and related pathways for differentiation remain unclear. This study screened and identified differentially expressed microRNAs in bone marrow-derived mesenchymal stem cells induced by Schwann cell-conditioned medium, and explored targets and related pathways involved in their differentiation into neuronal-like cells. Primary bone marrow-derived mesenchymal stem cells were isolated from femoral and tibial bones, while primary Schwann cells were isolated from bilateral saphenous nerves. Bone marrow-derived mesenchymal stem cells were cultured in unconditioned (control group) and Schwann cell-conditioned medium (bone marrow-derived mesenchymal stem cell + Schwann cell group). Neuronal differentiation of bone marrow-derived mesenchymal stem cells induced by Schwann cell-conditioned medium was observed by time-lapse imaging. Upon induction, the morphology of bone marrow-derived mesenchymal stem cells changed into a neural shape with neurites. Results of quantitative reverse transcription-polymerase chain reaction revealed that nestin mRNA expression was upregulated from 1 to 3 days and downregulated from 3 to 7 days in the bone marrow-derived mesenchymal stem cell + Schwann cell group. Compared with the control group, microtubule-associated protein 2 mRNA expression gradually increased from 1 to 7 days in the bone marrow-derived mesenchymal stem cell + Schwann cell group. After 7 days of induction, microRNA analysis identified 83 significantly differentially expressed microRNAs between the two groups. Gene Ontology analysis indicated enrichment of microRNA target genes for neuronal projection development, regulation of axonogenesis, and positive regulation of cell proliferation. Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated that Hippo, Wnt, transforming growth factor-beta, and Hedgehog signaling pathways were potentially associated with neural differentiation of bone marrow-derived mesenchymal stem cells. This study, which carried out successful microRNA analysis of neuronal-like cells differentiated from bone marrow-derived mesenchymal stem cells by Schwann cell induction, revealed key microRNAs and pathways involved in neural differentiation of bone marrow-derived mesenchymal stem cells. All protocols were approved by the Animal Ethics Committee of Institute of Radiation Medicine, Chinese Academy of Medical Sciences on March 12, 2017 (approval number: DWLI-20170311).
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Affiliation(s)
- Zhi-Jian Wei
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Bao-You Fan
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Yang Liu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Han Ding
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Hao-Shuai Tang
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Da-Yu Pan
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Jia-Xiao Shi
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Peng-Yuan Zheng
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Hong-Yu Shi
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Heng Wu
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China
| | - Ang Li
- Department of Orthopedics, Henan Provincial People's Hospital, Zhengzhou, Henan Province, China
| | - Shi-Qing Feng
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
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Fukuoka M, Hohjoh H. Comprehensive Measurement of Gene Silencing Involving Endogenous MicroRNAs in Mammalian Cells. Methods Mol Biol 2018; 1733:181-192. [PMID: 29435933 DOI: 10.1007/978-1-4939-7601-0_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
MicroRNAs (miRNAs) are functional small noncoding RNAs that work as mediators in gene silencing and that play important roles in gene regulation. A number of miRNAs have been found and their expression profiles have been examined by means of various microarray systems and real-time polymerase chain reaction (PCR) systems. Conventional microarrays as well as real-time PCR are able to detect existing miRNAs, in which inactive miRNAs that hardly contribute to gene silencing may be also contained. Here, we describe a comprehensive miRNA bioassay system with reporter genes for the detection of active miRNAs that are present in the RNA-induced silencing complexes, and actually working as mediators in gene silencing.
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Roese-Koerner B, Stappert L, Brüstle O. Notch/Hes signaling and miR-9 engage in complex feedback interactions controlling neural progenitor cell proliferation and differentiation. NEUROGENESIS 2017; 4:e1313647. [PMID: 28573150 PMCID: PMC5443189 DOI: 10.1080/23262133.2017.1313647] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/27/2016] [Accepted: 01/18/2017] [Indexed: 02/04/2023]
Abstract
Canonical Notch signaling has diverse functions during nervous system development and is critical for neural progenitor self-renewal, timing of differentiation and specification of various cell fates. A key feature of Notch-mediated self-renewal is its fluctuating activity within the neural progenitor cell population and the oscillatory expression pattern of the Notch effector Hes1 and its target genes. A negative feedback loop between Hes1 and neurogenic microRNA miR-9 was found to be part of this oscillatory clock. In a recent study we discovered that miR-9 expression is further modulated by direct binding of the Notch intracellular domain/RBPj transcriptional complex to the miR-9_2 promoter. In turn, miR-9 not only targets Hes1 but also Notch2 to attenuate Notch signaling and promote neuronal differentiation. Here, we discuss how the two interwoven feedback loops may provide an additional fail-save mechanism to control proliferation and differentiation within the neural progenitor cell population. Furthermore, we explore potential implications of miR-9-mediated regulation of Notch/Hes1 signaling with regard to neural progenitor homeostasis, patterning, timing of differentiation and tumor formation.
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Affiliation(s)
- Beate Roese-Koerner
- Institute of Reconstructive Neurobiology, LIFE & BRAIN Center, University of Bonn Medical Faculty, Bonn, Germany
| | - Laura Stappert
- Institute of Reconstructive Neurobiology, LIFE & BRAIN Center, University of Bonn Medical Faculty, Bonn, Germany
| | - Oliver Brüstle
- Institute of Reconstructive Neurobiology, LIFE & BRAIN Center, University of Bonn Medical Faculty, Bonn, Germany
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Kelly GM, Gatie MI. Mechanisms Regulating Stemness and Differentiation in Embryonal Carcinoma Cells. Stem Cells Int 2017; 2017:3684178. [PMID: 28373885 PMCID: PMC5360977 DOI: 10.1155/2017/3684178] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 01/10/2017] [Accepted: 02/08/2017] [Indexed: 02/06/2023] Open
Abstract
Just over ten years have passed since the seminal Takahashi-Yamanaka paper, and while most attention nowadays is on induced, embryonic, and cancer stem cells, much of the pioneering work arose from studies with embryonal carcinoma cells (ECCs) derived from teratocarcinomas. This original work was broad in scope, but eventually led the way for us to focus on the components involved in the gene regulation of stemness and differentiation. As the name implies, ECCs are malignant in nature, yet maintain the ability to differentiate into the 3 germ layers and extraembryonic tissues, as well as behave normally when reintroduced into a healthy blastocyst. Retinoic acid signaling has been thoroughly interrogated in ECCs, especially in the F9 and P19 murine cell models, and while we have touched on this aspect, this review purposely highlights how some key transcription factors regulate pluripotency and cell stemness prior to this signaling. Another major focus is on the epigenetic regulation of ECCs and stem cells, and, towards that end, this review closes on what we see as a new frontier in combating aging and human disease, namely, how cellular metabolism shapes the epigenetic landscape and hence the pluripotency of all stem cells.
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Affiliation(s)
- Gregory M. Kelly
- Department of Biology, Molecular Genetics Unit, Western University, London, ON, Canada
- Collaborative Program in Developmental Biology, Western University, London, ON, Canada
- Department of Paediatrics and Department of Physiology and Pharmacology, Western University, London, ON, Canada
- Child Health Research Institute, London, ON, Canada
- Ontario Institute for Regenerative Medicine, Toronto, ON, Canada
- The Hospital for Sick Children, Toronto, ON, Canada
| | - Mohamed I. Gatie
- Department of Biology, Molecular Genetics Unit, Western University, London, ON, Canada
- Collaborative Program in Developmental Biology, Western University, London, ON, Canada
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MA LIJIE, LI PEIPEI, WANG RUIXUAN, NAN YANDONG, LIU XUEYING, JIN FAGUANG. Analysis of novel microRNA targets in drug-sensitive and -insensitive small cell lung cancer cell lines. Oncol Rep 2015; 35:1611-21. [DOI: 10.3892/or.2015.4487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/26/2015] [Indexed: 11/06/2022] Open
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Teng R, Hu Y, Zhou J, Seifer B, Chen Y, Shen J, Wang L. Overexpression of Lin28 Decreases the Chemosensitivity of Gastric Cancer Cells to Oxaliplatin, Paclitaxel, Doxorubicin, and Fluorouracil in Part via microRNA-107. PLoS One 2015; 10:e0143716. [PMID: 26636340 PMCID: PMC4670127 DOI: 10.1371/journal.pone.0143716] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 11/08/2015] [Indexed: 02/07/2023] Open
Abstract
Higher Lin28 expression is associated with worse pathologic tumor responses in locally advanced gastric cancer patients undergoing neoadjuvant chemotherapy. However, the characteristics of Lin28 and its mechanism of action in chemotherapy resistance is still unclear. In this study, we found that transfection of Lin28 into gastric cancer cells (MKN45 and MKN28) increased their resistance to the chemo-drugs oxaliplatin (OXA), paclitaxel (PTX), doxorubicin (ADM), and fluorouracil (5-Fu) compared with gastric cancer cells transfected with a control vector. When knockdown Lin28 expression by Lin28 small interfering RNA (siRNA) was evaluated in vitro, we found that the resistance to chemo-drugs was reduced. Furthermore, we found that Lin28 up-regulates C-myc and P-gp and down-regulates Cylin D1. Finally, we found that miR-107 is a target microRNA of Lin28 and that it participates in the mechanism of chemotherapy resistance. Our results suggest that the Lin28/miR-107 pathway could be one of many signaling pathways regulated by Lin28 and associated with gastric cancer chemo-resistance.
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Affiliation(s)
- Rongyue Teng
- Department of Surgical Oncology, Sir Run Run Shaw Hospital, Hangzhou, Zhejiang Province, People’s Republic of China
| | - Yan Hu
- Department of Surgical Oncology, Sir Run Run Shaw Hospital, Hangzhou, Zhejiang Province, People’s Republic of China
- Zhejiang University, Hangzhou, Zhejiang province, People’s Republic of China
| | - Jichun Zhou
- Zhejiang University, Hangzhou, Zhejiang province, People’s Republic of China
| | - Benjamin Seifer
- Postgraduate Research Associate Yale School of Medicine, Department of Ob/Gyn & Reproductive Sciences, New Haven, Connecticut, United States of America
| | - Yongxia Chen
- Department of Surgical Oncology, Sir Run Run Shaw Hospital, Hangzhou, Zhejiang Province, People’s Republic of China
| | - Jianguo Shen
- Department of Surgical Oncology, Sir Run Run Shaw Hospital, Hangzhou, Zhejiang Province, People’s Republic of China
- * E-mail: (JS); (LW)
| | - Linbo Wang
- Department of Surgical Oncology, Sir Run Run Shaw Hospital, Hangzhou, Zhejiang Province, People’s Republic of China
- * E-mail: (JS); (LW)
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Yang Y, Zhang P, Zhao Y, Yang J, Jiang G, Fan J. Decreased MicroRNA-26a expression causes cisplatin resistance in human non-small cell lung cancer. Cancer Biol Ther 2015; 17:515-25. [PMID: 26492332 DOI: 10.1080/15384047.2015.1095405] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Lung cancer is the most common cancer that is caused by perturbation of regulatory pathways rather than dysfunction of a single gene. Cisplatin (CDDP; cis-diamminedichloroplatinum II) is the first member of a class of platinum-containing anti-cancer medication, which binds to DNA and triggers apoptosis. CDDP-based chemotherapy is used to treat various types of cancers. However, the efficacy of CDDP in the treatment of non-small-cell lung cancer (NSCLC) is limited by acquired drug resistance. MicroRNAs have recently emerged as key regulators of cancers, and miR-26a is one of down-regulated miRNAs in A549/CDDPres cell line. This study aimed to investigate the role of miR-26a in CDDP resistance in NSCLC as well as the underlying mechanisms. METHODS In this study, we analyzed expressional profiles of CDDP resistance-related mRNA, miRNA, and transcription factors (TF) that regulate miRNA expression in NSCLC. A549 cells were treated with CDDP, miR-26a mimic, or miR-26a inhibitor, and followed by biological analysis including drug sensitivity assay, colony formation assay, terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling (TUNEL) assay, and cell cycle analysis. Luciferase assay was used to determine the target of miR-26a. The regulation of miR-26a in Akt pathway was measured by western blot. RESULTS High mobility group A (HMGA) 2 was identified as the target of miR-26a. Overexpression of miR-26a in A549 cells inhibited G1-S transition, increased cell death in response to CDDP treatment, and decreased the colony formation of A549 cells. MiR-26a significantly decreased the expression of E2F1, diminished Akt phosphorylation, and downregulated Bcl2 expression. Cell growth was suppressed by inhibiting HMGA2-mediated E2F1-Akt pathway. CONCLUSION MiR-26a is responsible for A549 cell sensitivity in the treatment of CDDP through regulating HMGA2-mediated E2F1-Akt pathway.
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Affiliation(s)
- Yong Yang
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China
| | - Peng Zhang
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China
| | - Yanfeng Zhao
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China
| | - Jie Yang
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China
| | - Gening Jiang
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China
| | - Jie Fan
- a Department of Thoracic Surgery , Shanghai Pulmonary Hospital, Tongji University School of Medicine , Shanghai , China.,b Department of Surgery , University of Pittsburgh School of Medicine , Pittsburgh , PA , USA
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9
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Fukuoka M, Yoshida M, Eda A, Takahashi M, Hohjoh H. Gene silencing mediated by endogenous microRNAs under heat stress conditions in mammalian cells. PLoS One 2014; 9:e103130. [PMID: 25068899 PMCID: PMC4113354 DOI: 10.1371/journal.pone.0103130] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 06/27/2014] [Indexed: 12/21/2022] Open
Abstract
Heat shock, sudden change in temperature, triggers various responses in cells for protecting the cells from such a severe circumstance. Here we investigated gene silencing mediated by endogenous microRNAs (miRNAs) in mammalian cells exposed to a mild hyperthermia, by means of miRNA activity assay using a luciferase reporter gene as well as miRNA expression analysis using a DNA microarray. Our findings indicated that the gene silencing activities involving miRNAs were enhanced without increasing in their expression levels under heat-stress conditions. Additionally, the gene silencing activity appeared to be independent of the cytoprotective action involving heat shock proteins that are immediately activated in heat-shocked cells and that function as molecular chaperons for restoring heat-denatured proteins to normal proteins. Our current findings suggested the possibility that gene silencing involving endogenous miRNAs might play a subsidiary role in heat-shocked cells for an aggressive inhibition of the expression of heat-denatured proteins.
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Affiliation(s)
- Masashi Fukuoka
- Department of Molecular Pharmacology, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan
| | - Mariko Yoshida
- Department of Molecular Pharmacology, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan
| | - Akiko Eda
- Department of Molecular Pharmacology, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan
| | - Masaki Takahashi
- Department of Molecular Pharmacology, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan
| | - Hirohiko Hohjoh
- Department of Molecular Pharmacology, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan
- * E-mail:
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10
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Dorweiler JE, Ni T, Zhu J, Munroe SH, Anderson JT. Certain adenylated non-coding RNAs, including 5' leader sequences of primary microRNA transcripts, accumulate in mouse cells following depletion of the RNA helicase MTR4. PLoS One 2014; 9:e99430. [PMID: 24926684 PMCID: PMC4057207 DOI: 10.1371/journal.pone.0099430] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 05/14/2014] [Indexed: 12/30/2022] Open
Abstract
RNA surveillance plays an important role in posttranscriptional regulation. Seminal work in this field has largely focused on yeast as a model system, whereas exploration of RNA surveillance in mammals is only recently begun. The increased transcriptional complexity of mammalian systems provides a wider array of targets for RNA surveillance, and, while many questions remain unanswered, emerging data suggest the nuclear RNA surveillance machinery exhibits increased complexity as well. We have used a small interfering RNA in mouse N2A cells to target the homolog of a yeast protein that functions in RNA surveillance (Mtr4p). We used high-throughput sequencing of polyadenylated RNAs (PA-seq) to quantify the effects of the mMtr4 knockdown (KD) on RNA surveillance. We demonstrate that overall abundance of polyadenylated protein coding mRNAs is not affected, but several targets of RNA surveillance predicted from work in yeast accumulate as adenylated RNAs in the mMtr4KD. microRNAs are an added layer of transcriptional complexity not found in yeast. After Drosha cleavage separates the pre-miRNA from the microRNA's primary transcript, the byproducts of that transcript are generally thought to be degraded. We have identified the 5′ leading segments of pri-miRNAs as novel targets of mMtr4 dependent RNA surveillance.
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Affiliation(s)
- Jane E. Dorweiler
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, United States of America
| | - Ting Ni
- DNA Sequencing and Genomics Core, Genetics and Development Biology Center, National Institutes of Health, National Heart Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Jun Zhu
- DNA Sequencing and Genomics Core, Genetics and Development Biology Center, National Institutes of Health, National Heart Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Stephen H. Munroe
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, United States of America
- * E-mail: (JTA); (SHM)
| | - James T. Anderson
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, United States of America
- * E-mail: (JTA); (SHM)
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Al-Lamki RS, Lu W, Wang J, Yang J, Sargeant TJ, Wells R, Suo C, Wright P, Goddard M, Huang Q, Lebastchi AH, Tellides G, Huang Y, Min W, Pober JS, Bradley JR. TNF, acting through inducibly expressed TNFR2, drives activation and cell cycle entry of c-Kit+ cardiac stem cells in ischemic heart disease. Stem Cells 2014; 31:1881-92. [PMID: 23712715 DOI: 10.1002/stem.1433] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 04/15/2013] [Accepted: 04/22/2013] [Indexed: 12/25/2022]
Abstract
TNF, signaling through TNFR2, has been implicated in tissue repair, a process that in the heart may be mediated by activated resident cardiac stem cells (CSCs). The objective of our study is to determine whether ligation of TNFR2 can induce activation of resident CSCs in the setting of ischemic cardiac injury. We show that in human cardiac tissue affected by ischemia heart disease (IHD), TNFR2 is expressed on intrinsic CSCs, identified as c-kit(+)/CD45(-)/VEGFR2(-) interstitial round cells, which are activated as determined by entry to cell cycle and expression of Lin-28. Wild-type mouse heart organ cultures subjected to hypoxic conditions both increase cardiac TNF expression and show induced TNFR2 and Lin-28 expression in c-kit(+) CSCs that have entered cell cycle. These CSC responses are enhanced by exogenous TNF. TNFR2(-/-) mouse heart organ cultures subjected to hypoxia increase cardiac TNF but fail to induce CSC activation. Similarly, c-kit(+) CSCs isolated from mouse hearts exposed to hypoxia or TNF show induction of Lin-28, TNFR2, cell cycle entry, and cardiogenic marker, α-sarcomeric actin (α-SA), responses more pronounced by hypoxia in combination with TNF. Knockdown of Lin-28 by siRNA results in reduced levels of TNFR2 expression, cell cycle entry, and diminished expression of α-SA. We conclude that hypoxia-induced c-kit(+) CSC activation is mediated by TNF/TNFR2/Lin-28 signaling. These observations suggest that TNFR2 signaling in resident c-kit(+) CSCs induces cardiac repair, findings which provide further understanding of the unanticipated harmful effects of TNF blockade in human IHD.
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Affiliation(s)
- Rafia S Al-Lamki
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
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12
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Zhou H, Guo W, Zhao Y, Wang Y, Zha R, Ding J, Liang L, Hu J, Shen H, Chen Z, Yin B, Ma B. MicroRNA-26a acts as a tumor suppressor inhibiting gallbladder cancer cell proliferation by directly targeting HMGA2. Int J Oncol 2014; 44:2050-8. [PMID: 24682444 DOI: 10.3892/ijo.2014.2360] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 03/13/2014] [Indexed: 01/12/2023] Open
Abstract
MicroRNAs (miRNAs) are a class of small, single-stranded, non-coding RNA molecules which can act as oncogenes or tumor suppressor genes in human cancer. However, the possible functions and mechanisms of miRNA action in gallbladder cancer (GBC) have not been elucidated. In the present study, it was found that miR-26a was often downregulated in GBC and the expression of miR-26a was associated with neoplasm histological grade. miR-26a significantly inhibited the proliferation of GBC cells based on the gain-of-function assays. Furthermore, we demonstrated that high mobility group AT-hook 2 (HMGA2) was a direct target of miR-26a. The results showed that HMGA2 mRNA levels and miR-26a levels were negatively correlated. In addition, we confirmed that reintroduction of HMGA2 antagonized the inhibition of miR-26a to GBC cell proliferation and all these effects were achieved through the cell cycle. Together, all these results suggest that miR-26a expression contributes to GBC proliferation by targeting HMGA2. miR-26a shows promise as a prognosis factor and therapeutic target of GBC patients.
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Affiliation(s)
- Huading Zhou
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Weijie Guo
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, School of Medicine, Shanghai 200032, P.R. China
| | - Yingjun Zhao
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, School of Medicine, Shanghai 200032, P.R. China
| | - Yifei Wang
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Ruopeng Zha
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, School of Medicine, Shanghai 200032, P.R. China
| | - Jie Ding
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, School of Medicine, Shanghai 200032, P.R. China
| | - Linhui Liang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, School of Medicine, Shanghai 200032, P.R. China
| | - Jun Hu
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Hao Shen
- Jing'an District Center Hospital of Shanghai Huashan Hospital, Fudan University, Jing'an Branch, Shanghai 200040, P.R. China
| | - Zongyou Chen
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Baobing Yin
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Baojin Ma
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
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13
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Coolen M, Katz S, Bally-Cuif L. miR-9: a versatile regulator of neurogenesis. Front Cell Neurosci 2013; 7:220. [PMID: 24312010 PMCID: PMC3834235 DOI: 10.3389/fncel.2013.00220] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 10/31/2013] [Indexed: 12/21/2022] Open
Abstract
Soon after its discovery, microRNA-9 (miR-9) attracted the attention of neurobiologists, since it is one of the most highly expressed microRNAs in the developing and adult vertebrate brain. Functional analyses in different vertebrate species have revealed a prominent role of this microRNA in balancing proliferation in embryonic neural progenitor populations. Key transcriptional regulators such as FoxG1, Hes1 or Tlx, were identified as direct targets of miR-9, placing it at the core of the gene network controlling the progenitor state. Recent data also suggest that this function could extend to adult neural stem cells. Other studies point to a role of miR-9 in differentiated neurons. Moreover miR-9 has been implicated in human brain pathologies, either displaying a protective role, such as in Progeria, or participating in disease progression in brain cancers. Altogether functional studies highlight a prominent feature of this highly conserved microRNA, its functional versatility, both along its evolutionary history and across cellular contexts.
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Affiliation(s)
- Marion Coolen
- Zebrafish Neurogenetics Team, Laboratory of Neurobiology and Development, Institute of Neurobiology Alfred Fessard, CNRS Gif-sur-Yvette, France
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14
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LIN28B-mediated expression of fetal hemoglobin and production of fetal-like erythrocytes from adult human erythroblasts ex vivo. Blood 2013; 122:1034-41. [PMID: 23798711 DOI: 10.1182/blood-2012-12-472308] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Reactivation of fetal hemoglobin (HbF) holds therapeutic potential for sickle cell disease and β-thalassemias. In human erythroid cells and hematopoietic organs, LIN28B and its targeted let-7 microRNA family, demonstrate regulated expression during the fetal-to-adult developmental transition. To explore the effects of LIN28B in human erythroid cell development, lentiviral transduction was used to knockdown LIN28B expression in erythroblasts cultured from human umbilical cord CD34+ cells. The subsequent reduction in LIN28B expression caused increased expression of let-7 and significantly reduced HbF expression. Conversely, LIN28B overexpression in cultured adult erythroblasts reduced the expression of let-7 and significantly increased HbF expression. Cellular maturation was maintained including enucleation. LIN28B expression in adult erythroblasts increased the expression of γ-globin, and the HbF content of the cells rose to levels >30% of their hemoglobin. Expression of carbonic anhydrase I, glucosaminyl (N-acetyl) transferase 2, and miR-96 (three additional genes marking the transition from fetal-to-adult erythropoiesis) were reduced by LIN28B expression. The transcription factor BCL11A, a well-characterized repressor of γ-globin expression, was significantly down-regulated. Independent of LIN28B, experimental suppression of let-7 also reduced BCL11A expression and significantly increased HbF expression. LIN28B expression regulates HbF levels and causes adult human erythroblasts to differentiate with a more fetal-like phenotype.
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15
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Conserved microRNA pathway regulates developmental timing of retinal neurogenesis. Proc Natl Acad Sci U S A 2013; 110:E2362-70. [PMID: 23754433 DOI: 10.1073/pnas.1301837110] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Most regions of the vertebrate central nervous system develop by the sequential addition of different classes of neurons and glia. This phenomenon has been best characterized in laminated structures like the retina and the cerebral cortex, in which the progenitor cells in these structures are thought to change in their competence as development proceeds to generate different types of neurons in a stereotypic sequence that is conserved across vertebrates. We previously reported that conditional deletion of Dicer prevents the change in competence of progenitors to generate later-born cell types, suggesting that specific microRNAs (miRNAs) are required for this developmental transition. In this report, we now show that three miRNAs, let-7, miR-125, and miR-9, are key regulators of the early to late developmental transition in retinal progenitors: (i) members of these three miRNA families increase over the relevant developmental period in normal retinal progenitors; (ii) inhibiting the function of these miRNAs produces changes in retinal development similar to Dicer CKO; (iii) overexpression of members of these three miRNA families in Dicer-CKO retinas can rescue the phenotype, allowing their progression to late progenitors; (iv) overexpression of these miRNAs can accelerate normal retinal development; (v) microarray and computational analyses of Dicer-CKO retinal cells identified two potential targets of the late-progenitor miRNAs: Protogenin (Prtg) and Lin28b; and (vi) overexpression of either Lin28 or Prtg can maintain the early progenitor state. Together, these data demonstrate that a conserved miRNA pathway controls a key step in the progression of temporal identity in retinal progenitors.
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16
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Conserved microRNA pathway regulates developmental timing of retinal neurogenesis. Proc Natl Acad Sci U S A 2013. [PMID: 23754433 DOI: 10.1073/pnas.13018371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Most regions of the vertebrate central nervous system develop by the sequential addition of different classes of neurons and glia. This phenomenon has been best characterized in laminated structures like the retina and the cerebral cortex, in which the progenitor cells in these structures are thought to change in their competence as development proceeds to generate different types of neurons in a stereotypic sequence that is conserved across vertebrates. We previously reported that conditional deletion of Dicer prevents the change in competence of progenitors to generate later-born cell types, suggesting that specific microRNAs (miRNAs) are required for this developmental transition. In this report, we now show that three miRNAs, let-7, miR-125, and miR-9, are key regulators of the early to late developmental transition in retinal progenitors: (i) members of these three miRNA families increase over the relevant developmental period in normal retinal progenitors; (ii) inhibiting the function of these miRNAs produces changes in retinal development similar to Dicer CKO; (iii) overexpression of members of these three miRNA families in Dicer-CKO retinas can rescue the phenotype, allowing their progression to late progenitors; (iv) overexpression of these miRNAs can accelerate normal retinal development; (v) microarray and computational analyses of Dicer-CKO retinal cells identified two potential targets of the late-progenitor miRNAs: Protogenin (Prtg) and Lin28b; and (vi) overexpression of either Lin28 or Prtg can maintain the early progenitor state. Together, these data demonstrate that a conserved miRNA pathway controls a key step in the progression of temporal identity in retinal progenitors.
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Hohjoh H. MicroRNA expression during neuronal differentiation of human teratocarcinoma NTera2D1 and mouse embryonic carcinoma P19 cells. Methods Mol Biol 2013; 936:257-269. [PMID: 23007514 DOI: 10.1007/978-1-62703-083-0_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
MicroRNAs (miRNAs) are 21-23-nucleotide-long small noncoding RNAs, function as mediators in gene silencing, and play essential roles in gene regulation in development, differentiation, and proliferation. Hundreds of miRNAs have been found, and tissue-specific or organ-specific expression of miRNAs has been detected. Here, I describe procedures for detection of miRNAs in the course of neuronal differentiation of human teratocarcinoma NTera2D1 and mouse embryonic carcinoma P19 cells.
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Affiliation(s)
- Hirohiko Hohjoh
- National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan.
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Molenaar JJ, Domingo-Fernández R, Ebus ME, Lindner S, Koster J, Drabek K, Mestdagh P, van Sluis P, Valentijn LJ, van Nes J, Broekmans M, Haneveld F, Volckmann R, Bray I, Heukamp L, Sprüssel A, Thor T, Kieckbusch K, Klein-Hitpass L, Fischer M, Vandesompele J, Schramm A, van Noesel MM, Varesio L, Speleman F, Eggert A, Stallings RL, Caron HN, Versteeg R, Schulte JH. LIN28B induces neuroblastoma and enhances MYCN levels via let-7 suppression. Nat Genet 2012; 44:1199-206. [PMID: 23042116 DOI: 10.1038/ng.2436] [Citation(s) in RCA: 303] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 09/12/2012] [Indexed: 12/14/2022]
Abstract
LIN28B regulates developmental processes by modulating microRNAs (miRNAs) of the let-7 family. A role for LIN28B in cancer has been proposed but has not been established in vivo. Here, we report that LIN28B showed genomic aberrations and extensive overexpression in high-risk neuroblastoma compared to several other tumor entities and normal tissues. High LIN28B expression was an independent risk factor for adverse outcome in neuroblastoma. LIN28B signaled through repression of the let-7 miRNAs and consequently resulted in elevated MYCN protein expression in neuroblastoma cells. LIN28B-let-7-MYCN signaling blocked differentiation of normal neuroblasts and neuroblastoma cells. These findings were fully recapitulated in a mouse model in which LIN28B expression in the sympathetic adrenergic lineage induced development of neuroblastomas marked by low let-7 miRNA levels and high MYCN protein expression. Interference with this pathway might offer therapeutic perspectives.
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Affiliation(s)
- Jan J Molenaar
- Department of Oncogenomics, Academic Medical Center, Amsterdam, The Netherlands.
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19
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Effects of high-mobility group a protein application on canine adipose-derived mesenchymal stem cells in vitro. Vet Med Int 2012; 2012:752083. [PMID: 22448338 PMCID: PMC3289926 DOI: 10.1155/2012/752083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/21/2011] [Accepted: 10/25/2011] [Indexed: 11/17/2022] Open
Abstract
Multipotency and self-renewal are considered as most important features of stem cells to persist throughout life in tissues. In this context, the role of HMGA proteins to influence proliferation of adipose-derived mesenchymal stem cell (ASCs) while maintaining their multipotent and self-renewal capacities has not yet been investigated. Therefore, extracellular HMGA1 and HMGA2 application alone (10-200 ng/mL) and in combination with each other (100, 200 ng/mL each) was investigated with regard to proliferative effects on canine ASCs (cASCs) after 48 hours of cultivation. Furthermore, mRNA expression of multipotency marker genes in unstimulated and HMGA2-stimulated cASCs (50, 100 ng/mL) was analyzed by RT-qPCR. HMGA1 significantly reduced cASCs proliferation in concentrations of 10-200 ng/mL culture medium. A combination of HMGA1 and HMGA2 protein (100 and 200 ng/mL each) caused the same effects, whereas no significant effect on cASCs proliferation was shown after HMGA2 protein application alone. RT-qPCR results showed that expression levels of marker genes including KLF4, SOX2, OCT4, HMGA2, and cMYC mRNAs were on the same level in both HMGA2-protein-stimulated and -unstimulated cASCs. Extracellular HMGA protein application might be valuable to control proliferation of cASCs in context with their employment in regenerative approaches without affecting their self-renewal and multipotency abilities.
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Eda A, Takahashi M, Fukushima T, Hohjoh H. Alteration of microRNA expression in the process of mouse brain growth. Gene 2011; 485:46-52. [DOI: 10.1016/j.gene.2011.05.034] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 05/28/2011] [Accepted: 05/30/2011] [Indexed: 11/25/2022]
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Zhang X, Virtanen A, Kleiman FE. To polyadenylate or to deadenylate: that is the question. Cell Cycle 2010; 9:4437-49. [PMID: 21084869 DOI: 10.4161/cc.9.22.13887] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
mRNA polyadenylation and deadenylation are important processes that allow rapid regulation of gene expression in response to different cellular conditions. Almost all eukaryotic mRNA precursors undergo a co-transcriptional cleavage followed by polyadenylation at the 3' end. After the signals are selected, polyadenylation occurs to full extent, suggesting that this first round of polyadenylation is a default modification for most mRNAs. However, the length of these poly(A) tails changes by the activation of deadenylation, which might regulate gene expression by affecting mRNA stability, mRNA transport, or translation initiation. The mechanisms behind deadenylation activation are highly regulated and associated with cellular conditions such as development, mRNA surveillance, DNA damage response, cell differentiation and cancer. After deadenylation, depending on the cellular response, some mRNAs might undergo an extension of the poly(A) tail or degradation. The polyadenylation/deadenylation machinery itself, miRNAs, or RNA binding factors are involved in the regulation of polyadenylation/deadenylation. Here, we review the mechanistic connections between polyadenylation and deadenylation and how the two processes are regulated in different cellular conditions. It is our conviction that further studies of the interplay between polyadenylation and deadenylation will provide critical information required for a mechanistic understanding of several diseases, including cancer development.
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Affiliation(s)
- Xiaokan Zhang
- Chemistry Department, Hunter College, City University of New York, NY, USA
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Lee S, Jung JW, Park SB, Roh K, Lee SY, Kim JH, Kang SK, Kang KS. Histone deacetylase regulates high mobility group A2-targeting microRNAs in human cord blood-derived multipotent stem cell aging. Cell Mol Life Sci 2010; 68:325-36. [PMID: 20652617 PMCID: PMC3016490 DOI: 10.1007/s00018-010-0457-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/01/2010] [Accepted: 07/05/2010] [Indexed: 12/31/2022]
Abstract
Cellular senescence involves a reduction in adult stem cell self-renewal, and epigenetic regulation of gene expression is one of the main underlying mechanisms. Here, we observed that the cellular senescence of human umbilical cord blood-derived multipotent stem cells (hUCB-MSCs) caused by inhibition of histone deacetylase (HDAC) activity leads to down-regulation of high mobility group A2 (HMGA2) and, on the contrary, to up-regulation of p16INK4A, p21CIP1/WAF1 and p27KIP1. We found that let-7a1, let-7d, let-7f1, miR-23a, miR-26a and miR-30a were increased during replicative and HDAC inhibitor-mediated senescence of hUCB-MSCs by microRNA microarray and real-time quantitative PCR. Furthermore, the configurations of chromatins beading on these miRNAs were prone to transcriptional activation during HDAC inhibitor-mediated senescence. We confirmed that miR-23a, miR-26a and miR-30a inhibit HMGA2 to accelerate the progress of senescence. These findings suggest that HDACs may play important roles in cellular senescence by regulating the expression of miRNAs that target HMGA2 through histone modification.
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Affiliation(s)
- Seunghee Lee
- Adult Stem Cell Research Center, Seoul National University, Republic of Korea
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Dicer is required for the transition from early to late progenitor state in the developing mouse retina. J Neurosci 2010; 30:4048-61. [PMID: 20237275 DOI: 10.1523/jneurosci.4982-09.2010] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
MicroRNAs (miRNAs), small 19-25 nucleotide RNAs that influence gene expression through posttranscriptional regulation of mRNA translation and degradation, have recently emerged as important regulators of neural development. Using conditional knock-out of Dicer, an RNase III enzyme required for miRNA maturation, previous studies have demonstrated an essential role for miRNAs in mouse cortical, inner ear, and olfactory development. However, a previous study (Damiani et al., 2008) using a Chx10cre mouse to delete Dicer in retinal progenitors reported no defects in the retina before the second postnatal week, suggesting that miRNAs are not required for mouse retinal development. In an effort to further study the role of miRNAs during retinal development and resolve this apparent conflict, we conditionally knocked out Dicer using a different (alphaPax6cre) line of transgenic mice. In contrast to the previous study, we demonstrate an essential role for miRNAs during mouse retinal development. In the absence of Dicer in the embryonic retina, production of early generated cell types (ganglion and horizontal cells) is increased, and markers of late progenitors are not expressed. This phenotype persists into postnatal retina, in which we find the Dicer-deficient progenitors fail to generate late-born cell types such as rods and Müller glia but continue to generate ganglion cells. We further characterize the dynamic expression of miRNAs during retinal progenitor differentiation and provide a comprehensive profile of miRNAs expressed during retinal development. We conclude that Dicer is necessary for the developmental change in competence of the retinal progenitor cells.
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