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Zakutansky PM, Ku L, Zhang G, Shi L, Li Y, Yao B, Bassell GJ, Read RD, Feng Y. Isoform balance of the long noncoding RNA NEAT1 is regulated by the RNA-binding protein QKI, governs the glioma transcriptome, and impacts cell migration. J Biol Chem 2024; 300:107595. [PMID: 39032650 PMCID: PMC11367543 DOI: 10.1016/j.jbc.2024.107595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 07/02/2024] [Accepted: 07/14/2024] [Indexed: 07/23/2024] Open
Abstract
The long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is involved in a variety of human cancers. Two overlapping NEAT1 isoforms, NEAT1_1 and NEAT1_2, are produced through mutually exclusive alternative 3' end formation. Previous studies extensively investigated NEAT1 dysregulation in tumors, but often failed to achieve distinct quantification of the two NEAT1 isoforms. Moreover, molecular mechanisms governing the biogenesis of NEAT1 isoforms and the functional impacts of their dysregulation in tumorigenesis remain poorly understood. In this study, we employed an isoform-specific quantification assay and found differential dysregulation of NEAT1 isoforms in patient-derived glioblastoma multiforme cells. We further showed usage of the NEAT1 proximal polyadenylation site (PAS) is a critical mechanism that controls glioma NEAT1 isoform production. CRISPR-Cas9-mediated PAS deletion reduced NEAT1_1 and reciprocally increased NEAT1_2, which enhanced nuclear paraspeckle formation in human glioma cells. Moreover, the utilization of the NEAT1 PAS is facilitated by the RNA-binding protein quaking (QKI), which binds to the proximal QKI recognition elements. Functionally, we identified transcriptomic changes and altered biological pathways caused by NEAT1 isoform imbalance in glioma cells, including the pathway for the regulation of cell migration. Finally, we demonstrated the forced increase of NEAT1_2 upon NEAT1 PAS deletion is responsible for driving glioma cell migration and promoting the expression of genes implicated in the regulation of cell migration. Together, our studies uncovered a novel mechanism that regulates NEAT1 isoforms and their functional impacts on the glioma transcriptome, which affects pathological pathways of glioma, represented by migration.
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Affiliation(s)
- Paul M Zakutansky
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell, and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA
| | - Li Ku
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Guannan Zhang
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Liang Shi
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Yangping Li
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Bing Yao
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Gary J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Renee D Read
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, Georgia, USA; Winship Cancer Institute, Emory University, Atlanta, Georgia, USA
| | - Yue Feng
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA.
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2
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Zhao Z, Qing Y, Dong L, Han L, Wu D, Li Y, Li W, Xue J, Zhou K, Sun M, Tan B, Chen Z, Shen C, Gao L, Small A, Wang K, Leung K, Zhang Z, Qin X, Deng X, Xia Q, Su R, Chen J. QKI shuttles internal m 7G-modified transcripts into stress granules and modulates mRNA metabolism. Cell 2023; 186:3208-3226.e27. [PMID: 37379838 PMCID: PMC10527483 DOI: 10.1016/j.cell.2023.05.047] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 11/28/2022] [Accepted: 05/29/2023] [Indexed: 06/30/2023]
Abstract
N7-methylguanosine (m7G) modification, routinely occurring at mRNA 5' cap or within tRNAs/rRNAs, also exists internally in messenger RNAs (mRNAs). Although m7G-cap is essential for pre-mRNA processing and protein synthesis, the exact role of mRNA internal m7G modification remains elusive. Here, we report that mRNA internal m7G is selectively recognized by Quaking proteins (QKIs). By transcriptome-wide profiling/mapping of internal m7G methylome and QKI-binding sites, we identified more than 1,000 high-confidence m7G-modified and QKI-bound mRNA targets with a conserved "GANGAN (N = A/C/U/G)" motif. Strikingly, QKI7 interacts (via C terminus) with the stress granule (SG) core protein G3BP1 and shuttles internal m7G-modified transcripts into SGs to regulate mRNA stability and translation under stress conditions. Specifically, QKI7 attenuates the translation efficiency of essential genes in Hippo signaling pathways to sensitize cancer cells to chemotherapy. Collectively, we characterized QKIs as mRNA internal m7G-binding proteins that modulate target mRNA metabolism and cellular drug resistance.
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Affiliation(s)
- Zhicong Zhao
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Ying Qing
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Lei Dong
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Li Han
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; School of Pharmacy, China Medical University, Shenyang, Liaoning 110001, China
| | - Dong Wu
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Yangchan Li
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; Department of Radiation Oncology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China
| | - Wei Li
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Jianhuang Xue
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital affiliated to Tongji University, Shanghai 200065, China; Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Keren Zhou
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Miao Sun
- Keck School of Medicine, University of Southern California, and Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - Brandon Tan
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Zhenhua Chen
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Chao Shen
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Lei Gao
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Andrew Small
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Kitty Wang
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Keith Leung
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Zheng Zhang
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Xi Qin
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Xiaolan Deng
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Qiang Xia
- Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
| | - Rui Su
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA.
| | - Jianjun Chen
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; City of Hope Comprehensive Cancer Center, City of Hope, Duarte, CA 91010, USA.
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3
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Que Z, Yang K, Wang N, Li S, Li T. Functional Role of RBP in Osteosarcoma: Regulatory Mechanism and Clinical Therapy. Anal Cell Pathol (Amst) 2023; 2023:9849719. [PMID: 37426488 PMCID: PMC10328736 DOI: 10.1155/2023/9849719] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/06/2023] [Accepted: 06/11/2023] [Indexed: 07/11/2023] Open
Abstract
Malignant bone neoplasms can be represented by osteosarcoma (OS), which accounts for 36% of all sarcomas. To reduce tumor malignancy, extensive efforts have been devoted to find an ideal target from numerous candidates, among which RNA-binding proteins (RBPs) have shown their unparalleled competitiveness. With the special structure of RNA-binding domains, RBPs have the potential to establish relationships with RNAs or small molecules and are considered regulators of different sections of RNA processes, including splicing, transport, translation, and degradation of RNAs. RBPs have considerable significant roles in various cancers, and experiments revealed that there was a strong association of RBPs with tumorigenesis and tumor cell progression. Regarding OS, RBPs are a new orientation, but achievements in hand are noteworthy. Higher or lower expression of RBPs was first found in tumor cells compared to normal tissue. By binding to different molecules, RBPs are capable of influencing tumor cell phenotypes through different signaling pathways or other axes, and researches on medical treatment have been largely inspired. Exploring the prognostic and therapeutic values of RBPs in OS is a hotspot where diverse avenues on regulating RBPs have achieved dramatical effects. In this review, we briefly summarize the contribution of RBPs and their binding molecules to OS oncogenicity and generally introduce distinctive RBPs as samples. Moreover, we focus on the attempts to differentiate RBP's opposite functions in predicting prognosis and collect possible strategies for treatment. Our review provides forwards insight into improving the understanding of OS and suggests RBPs as potential biomarkers for therapies.
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Affiliation(s)
- Ziyuan Que
- Yangzhou University Medical College, Yangzhou University, Yangzhou 225009, Jiangsu Province, China
| | - Kang Yang
- Department of Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou 310022, Zhejiang, China
| | - Nan Wang
- Yangzhou University Medical College, Yangzhou University, Yangzhou 225009, Jiangsu Province, China
| | - Shuying Li
- Yangzhou University Medical College, Yangzhou University, Yangzhou 225009, Jiangsu Province, China
| | - Tao Li
- Department of Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou 310022, Zhejiang, China
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Gong Z, Shen P, Wang H, Zhu J, Liang K, Wang K, Mi Y, Shen S, Fang X, Liu G. A novel circular RNA circRBMS3 regulates proliferation and metastasis of osteosarcoma by targeting miR-424-eIF4B/YRDC axis. Aging (Albany NY) 2023; 15:1564-1590. [PMID: 36897170 PMCID: PMC10042691 DOI: 10.18632/aging.204567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 01/23/2023] [Indexed: 03/11/2023]
Abstract
Circular RNAs (circRNAs) have been demonstrated to have critical regulatory roles in tumorigenesis. However, the contribution of circRNAs to OS (osteosarcoma) remains largely unknown. circRNA deep sequencing was performed to the expression of circRNAs between OS and chondroma tissues. The regulatory and functional role of circRBMS3 (a circRNA derived from exons 7 to 10 of the RBMS3 gene, hsa_circ_0064644) upregulation was examined in OS and was validated in vitro and in vivo, upstream regulator and downstream target of circRBMS3 were both explored. RNA pull down, a luciferase reporter assay, biotin-coupled microRNA capture and fluorescence in situ hybridization were used to evaluate the interaction between circRBMS3 and micro (mi)-R-424-5p. For in vivo tumorigenesis experiments, Subcutaneous and Orthotopic xenograft OS mouse models were built. Expression of circRBMS3 was higher in OS tissues due to the regulation of adenosine deaminase 1-acting on RNA (ADAR1), an abundant RNA editing enzyme. Our in vitro data indicated that ShcircRBMS3 inhibits the proliferation and migration of osteosarcoma cells. Mechanistically, we showed that circRBMS3 could regulate eIF4B and YRDC, through 'sponging' miR-424-5p. Furthermore, knockdown of circRBMS3 inhibited malignant phenotypes and bone destruction of OS in vivo. Our results reveal an important role for a novel circRBMS3 in the growth and metastasis of malignant tumor cells and offer a fresh perspective on circRNAs in OS progression.
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Affiliation(s)
- Zhe Gong
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Panyang Shen
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Haitao Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Jinjin Zhu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Kaiyu Liang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Kefan Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Yunfeng Mi
- Department of Orthopaedic Surgery, Ningbo First Hospital, Ningbo 315010, China
| | - Shuying Shen
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Xiangqian Fang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
| | - Gang Liu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University and Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou 310016, Zhejiang Province, China
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5
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Zhang L, Li D, Gao L, Fu J, Sun S, Huang H, Zhang D, Jia C, Zheng T, Cui B, Liu Y, Zhao Y. Promoter Methylation of QKI as a Potential Specific Biomarker for Early Detection of Colorectal Cancer. Front Genet 2022; 13:928150. [PMID: 36017498 PMCID: PMC9395658 DOI: 10.3389/fgene.2022.928150] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
Early and specific detection of cancer provides an opportunity for appropriate treatment. Although studies have suggested that QKI is a tumor suppressor gene, no studies have evaluated the diagnostic utility of QKI methylation in colorectal cancer (CRC). Here, we evaluated the methylation status of QKI by integrating the methylation data of tissues and cell lines of multiple cancer types. The diagnostic performance of QKI was analyzed in the discovery dataset from the TCGA CRC 450K array (n = 440) and tested in the test sets (n = 845) from the GEO. The methylation level of QKI was further validated in our independent dataset (n = 388) using targeted bisulfite sequencing. All detected CpG sites in the QKI promoter showed CRC-specific hypermethylation in 31 types of tumor tissues. In the discovery dataset, six consecutive CpG sites achieved high diagnostic performances, with AUCs ranging from 0.821 to 0.930. In the test set, a region (chr6: 163,834,452–163,834,924) including four consecutive CpG sites had robust diagnostic ability in distinguishing CRC and adenoma from normal samples. In the validation dataset, similar robust results were observed in both early- and advanced-stage CRC patients. In addition, QKI exhibited hypermethylation in the cfDNA of patients with CRC (n = 14). Collectively, the QKI promoter is a CRC-specific methylation biomarker and holds great promise for improving the diagnosis using minimally invasive biopsy.
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Affiliation(s)
- Lei Zhang
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Dapeng Li
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Lijing Gao
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Jinming Fu
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Simin Sun
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Hao Huang
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Ding Zhang
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Chenyang Jia
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Ting Zheng
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
| | - Binbin Cui
- Department of Colorectal Surgery, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, China
- *Correspondence: Yashuang Zhao, ; Yanlong Liu, ; Binbin Cui,
| | - Yanlong Liu
- Department of Colorectal Surgery, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, China
- *Correspondence: Yashuang Zhao, ; Yanlong Liu, ; Binbin Cui,
| | - Yashuang Zhao
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, China
- *Correspondence: Yashuang Zhao, ; Yanlong Liu, ; Binbin Cui,
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6
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Zakutansky PM, Feng Y. The Long Non-Coding RNA GOMAFU in Schizophrenia: Function, Disease Risk, and Beyond. Cells 2022; 11:1949. [PMID: 35741078 PMCID: PMC9221589 DOI: 10.3390/cells11121949] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/10/2022] [Accepted: 06/14/2022] [Indexed: 02/05/2023] Open
Abstract
Neuropsychiatric diseases are among the most common brain developmental disorders, represented by schizophrenia (SZ). The complex multifactorial etiology of SZ remains poorly understood, which reflects genetic vulnerabilities and environmental risks that affect numerous genes and biological pathways. Besides the dysregulation of protein-coding genes, recent discoveries demonstrate that abnormalities associated with non-coding RNAs, including microRNAs and long non-coding RNAs (lncRNAs), also contribute to the pathogenesis of SZ. lncRNAs are an actively evolving family of non-coding RNAs that harbor greater than 200 nucleotides but do not encode for proteins. In general, lncRNA genes are poorly conserved. The large number of lncRNAs specifically expressed in the human brain, together with the genetic alterations and dysregulation of lncRNA genes in the SZ brain, suggests a critical role in normal cognitive function and the pathogenesis of neuropsychiatric diseases. A particular lncRNA of interest is GOMAFU, also known as MIAT and RNCR2. Growing evidence suggests the function of GOMAFU in governing neuronal development and its potential roles as a risk factor and biomarker for SZ, which will be reviewed in this article. Moreover, we discuss the potential mechanisms through which GOMAFU regulates molecular pathways, including its subcellular localization and interaction with RNA-binding proteins, and how interruption to GOMAFU pathways may contribute to the pathogenesis of SZ.
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Affiliation(s)
- Paul M. Zakutansky
- Graduate Program in Biochemistry, Cell and Developmental Biology, Emory University, Atlanta, GA 30322, USA;
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Yue Feng
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
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7
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Panagopoulos I, Heim S. Interstitial Deletions Generating Fusion Genes. Cancer Genomics Proteomics 2021; 18:167-196. [PMID: 33893073 DOI: 10.21873/cgp.20251] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 12/16/2022] Open
Abstract
A fusion gene is the physical juxtaposition of two different genes resulting in a structure consisting of the head of one gene and the tail of the other. Gene fusion is often a primary neoplasia-inducing event in leukemias, lymphomas, solid malignancies as well as benign tumors. Knowledge about fusion genes is crucial not only for our understanding of tumorigenesis, but also for the diagnosis, prognostication, and treatment of cancer. Balanced chromosomal rearrangements, in particular translocations and inversions, are the most frequent genetic events leading to the generation of fusion genes. In the present review, we summarize the existing knowledge on chromosome deletions as a mechanism for fusion gene formation. Such deletions are mostly submicroscopic and, hence, not detected by cytogenetic analyses but by array comparative genome hybridization (aCGH) and/or high throughput sequencing (HTS). They are found across the genome in a variety of neoplasias. As tumors are increasingly analyzed using aCGH and HTS, it is likely that more interstitial deletions giving rise to fusion genes will be found, significantly impacting our understanding and treatment of cancer.
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Affiliation(s)
- Ioannis Panagopoulos
- Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway;
| | - Sverre Heim
- Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
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Bitaraf A, Razmara E, Bakhshinejad B, Yousefi H, Vatanmakanian M, Garshasbi M, Cho WC, Babashah S. The oncogenic and tumor suppressive roles of RNA-binding proteins in human cancers. J Cell Physiol 2021; 236:6200-6224. [PMID: 33559213 DOI: 10.1002/jcp.30311] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 01/14/2021] [Accepted: 01/22/2021] [Indexed: 12/17/2022]
Abstract
Posttranscriptional regulation is a mechanism for the cells to control gene regulation at the RNA level. In this process, RNA-binding proteins (RBPs) play central roles and orchestrate the function of RNA molecules in multiple steps. Accumulating evidence has shown that the aberrant regulation of RBPs makes contributions to the initiation and progression of tumorigenesis via numerous mechanisms such as genetic changes, epigenetic alterations, and noncoding RNA-mediated regulations. In this article, we review the effects caused by RBPs and their functional diversity in the malignant transformation of cancer cells that occurs through the involvement of these proteins in various stages of RNA regulation including alternative splicing, stability, polyadenylation, localization, and translation. Besides this, we review the various interactions between RBPs and other crucial posttranscriptional regulators such as microRNAs and long noncoding RNAs in the pathogenesis of cancer. Finally, we discuss the potential approaches for targeting RBPs in human cancers.
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Affiliation(s)
- Amirreza Bitaraf
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ehsan Razmara
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Babak Bakhshinejad
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hassan Yousefi
- Department of Biochemistry and Molecular Biology, LSUHSC School of Medicine, New Orleans, Louisiana, USA
| | - Mousa Vatanmakanian
- Department of Biochemistry and Molecular Biology, LSUHSC School of Medicine, New Orleans, Louisiana, USA
| | - Masoud Garshasbi
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong
| | - Sadegh Babashah
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
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9
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Fabbiano F, Corsi J, Gurrieri E, Trevisan C, Notarangelo M, D'Agostino VG. RNA packaging into extracellular vesicles: An orchestra of RNA-binding proteins? J Extracell Vesicles 2020; 10:e12043. [PMID: 33391635 PMCID: PMC7769857 DOI: 10.1002/jev2.12043] [Citation(s) in RCA: 130] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 11/17/2020] [Accepted: 12/03/2020] [Indexed: 12/11/2022] Open
Abstract
Extracellular vesicles (EVs) are heterogeneous membranous particles released from the cells through different biogenetic and secretory mechanisms. We now conceive EVs as shuttles mediating cellular communication, carrying a variety of molecules resulting from intracellular homeostatic mechanisms. The RNA is a widely detected cargo and, impressively, a recognized functional intermediate that elects EVs as modulators of cancer cell phenotypes, determinants of disease spreading, cell surrogates in regenerative medicine, and a source for non-invasive molecular diagnostics. The mechanistic elucidation of the intracellular events responsible for the engagement of RNA into EVs will significantly improve the comprehension and possibly the prediction of EV "quality" in association with cell physiology. Interestingly, the application of multidisciplinary approaches, including biochemical as well as cell-based and computational strategies, is increasingly revealing an active RNA-packaging process implicating RNA-binding proteins (RBPs) in the sorting of coding and non-coding RNAs. In this review, we provide a comprehensive view of RBPs recently emerging as part of the EV biology, considering the scenarios where: (i) individual RBPs were detected in EVs along with their RNA substrates, (ii) RBPs were detected in EVs with inferred RNA targets, and (iii) EV-transcripts were found to harbour sequence motifs mirroring the activity of RBPs. Proteins so far identified are members of the hnRNP family (hnRNPA2B1, hnRNPC1, hnRNPG, hnRNPH1, hnRNPK, and hnRNPQ), as well as YBX1, HuR, AGO2, IGF2BP1, MEX3C, ANXA2, ALIX, NCL, FUS, TDP-43, MVP, LIN28, SRP9/14, QKI, and TERT. We describe the RBPs based on protein domain features, current knowledge on the association with human diseases, recognition of RNA consensus motifs, and the need to clarify the functional significance in different cellular contexts. We also summarize data on previously identified RBP inhibitor small molecules that could also be introduced in EV research as potential modulators of vesicular RNA sorting.
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Affiliation(s)
- Fabrizio Fabbiano
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
| | - Jessica Corsi
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
| | - Elena Gurrieri
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
| | - Caterina Trevisan
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
| | - Michela Notarangelo
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
| | - Vito G. D'Agostino
- Department of CellularComputational and Integrative Biology (CIBIO)University of TrentoTrentoItaly
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10
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Takeuchi A, Takahashi Y, Iida K, Hosokawa M, Irie K, Ito M, Brown JB, Ohno K, Nakashima K, Hagiwara M. Identification of Qk as a Glial Precursor Cell Marker that Governs the Fate Specification of Neural Stem Cells to a Glial Cell Lineage. Stem Cell Reports 2020; 15:883-897. [PMID: 32976762 PMCID: PMC7562946 DOI: 10.1016/j.stemcr.2020.08.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 08/24/2020] [Accepted: 08/24/2020] [Indexed: 02/07/2023] Open
Abstract
During brain development, neural stem cells (NSCs) initially produce neurons and change their fate to generate glias. While the regulation of neurogenesis is well characterized, specific markers for glial precursor cells (GPCs) and the master regulators for gliogenesis remain unidentified. Accumulating evidence suggests that RNA-binding proteins (RBPs) have significant roles in neuronal development and function, as they comprehensively regulate the expression of target genes in a cell-type-specific manner. We systematically investigated the expression profiles of 1,436 murine RBPs in the developing mouse brain and identified quaking (Qk) as a marker of the putative GPC population. Functional analysis of the NSC-specific Qk-null mutant mouse revealed the key role of Qk in astrocyte and oligodendrocyte generation and differentiation from NSCs. Mechanistically, Qk upregulates gliogenic genes via quaking response elements in their 3′ untranslated regions. These results provide crucial directions for identifying GPCs and deciphering the regulatory mechanisms of gliogenesis from NSCs. Differential expression analysis identified Qk as a glial precursor cell marker Loss of Qk ablated both astrocyte and OL production from neural stem cells Qk−/− NSCs failed to become glia and aberrantly expressed neural genes Qk comprehensively upregulates essential genes for gliogenesis as regulons via QREs
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Affiliation(s)
- Akihide Takeuchi
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Yuji Takahashi
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kei Iida
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan; Medical Research Support Center, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Motoyasu Hosokawa
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Koichiro Irie
- Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
| | - Mikako Ito
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - J B Brown
- Laboratory for Molecular Biosciences, Life Science Informatics Research Unit, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kinji Ohno
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Kinichi Nakashima
- Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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11
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Hojo H, Yashiro Y, Noda Y, Ogami K, Yamagishi R, Okada S, Hoshino SI, Suzuki T. The RNA-binding protein QKI-7 recruits the poly(A) polymerase GLD-2 for 3' adenylation and selective stabilization of microRNA-122. J Biol Chem 2019; 295:390-402. [PMID: 31792053 DOI: 10.1074/jbc.ra119.011617] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/15/2019] [Indexed: 12/21/2022] Open
Abstract
MicroRNA-122 (miR-122) is highly expressed in hepatocytes, where it plays an important role in regulating cholesterol and fatty acid metabolism, and it is also a host factor required for hepatitis C virus replication. miR-122 is selectively stabilized by 3' adenylation mediated by the cytoplasmic poly(A) polymerase GLD-2 (also known as PAPD4 or TENT2). However, it is unclear how GLD-2 specifically stabilizes miR-122. Here, we show that QKI7 KH domain-containing RNA binding (QKI-7), one of three isoforms of the QKI proteins, which are members of the signal transduction and activation of RNA (STAR) family of RNA-binding proteins, is involved in miR-122 stabilization. QKI down-regulation specifically decreased the steady-state level of mature miR-122, but did not affect the pre-miR-122 level. We also found that QKI-7 uses its C-terminal region to interact with GLD-2 and its QUA2 domain to associate with the RNA-induced silencing complex protein Argonaute 2 (Ago2), indicating that the GLD-2-QKI-7 interaction recruits GLD-2 to Ago2. QKI-7 exhibited specific affinity to miR-122 and significantly promoted GLD-2-mediated 3' adenylation of miR-122 in vitro Taken together, our findings indicate that miR-122 binds Ago2-interacting QKI-7, which recruits GLD-2 for 3' adenylation and stabilization of miR-122.
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Affiliation(s)
- Hiroaki Hojo
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuka Yashiro
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuta Noda
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Koichi Ogami
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Ryota Yamagishi
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Shunpei Okada
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shin-Ichi Hoshino
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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12
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Yang H, Li Y, Peng Z, Wang Y. Overexpression of miR-20a promotes the progression of osteosarcoma by directly targeting QKI2. Oncol Lett 2019; 18:87-94. [PMID: 31289476 PMCID: PMC6540454 DOI: 10.3892/ol.2019.10313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 01/22/2019] [Indexed: 11/15/2022] Open
Abstract
Osteosarcoma (OS) is the most common type of malignant primary bone neoplasm. Although the application of neoadjuvant chemotherapy has improved the 5-year survival rate of patients suffering from OS, prognosis remains poor. Therefore, it is important to elucidate the molecular mechanisms underlying the occurrence, progression and metastasis of OS. The RNA-binding protein Quaking (QKI) is a member of the STAR family of proteins, and can function as a tumor suppressor gene to suppress the occurrence and progression of a variety of tumors; however, the role of QKI in OS remains to be fully elucidated. In the present study, it was identified that the expression of QKI2 was downregulated in OS using western blot analysis. In addition, subsequent functional investigations, including MTT, Transwell invasion and migration assays, revealed that QKI2 inhibited the proliferation, invasion and migration of an OS cell line in vitro. By implementing a series of experimental techniques in molecular biology, including reverse transcription-quantitative polymerase chain reaction and a double fluorescence reporter assay, it was demonstrated that the expression of miR-20a was high and inhibited the expression of QKI2 in OS. In conclusion, it was revealed that aberrantly upregulated miR-20a inhibited the expression of QKI2 in OS by targeting QKI2 mRNA, subsequently promoting the proliferation, migration and invasion of OS cells.
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Affiliation(s)
- Hongbo Yang
- Department of Orthopedic Surgery, Affiliated Hospital of Chifeng University, Chifeng, Inner Mongolia 024000, P.R. China
| | - Yongli Li
- Department of Tumor Radiotherapy, Heilongjiang Provincial Hospital, Harbin, Heilongjiang 150000, P.R. China
| | - Zhibin Peng
- Department of Orthopedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yansong Wang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
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13
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Gu S, Chu C, Chen W, Ren H, Cao Y, Li X, He J, Wang Y, Jin Y, Liu X, Zou Q. Prognostic value of epithelial-mesenchymal transition related genes: SLUG and QKI in breast cancer patients. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2019; 12:2009-2021. [PMID: 31934023 PMCID: PMC6949612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 03/11/2019] [Indexed: 06/10/2023]
Abstract
Snail family zinc finger 2 (SLUG) is related to epithelial-mesenchymal transition (EMT). Quaking (QKI) is an RNA binding protein and has been indicated to have a relationship with EMT by recent studies. The prognostic value of SLUG and QKI in breast cancer patients still needs exploration. We conducted Immunohistochemistry (IHC) to evaluate the protein expression of SLUG and QKI and the prognostic value in 108 breast cancer (BC) patients. The Bc-GenExMiner database was used to compare the mRNA levels of two genes in different subgroups of BC patients. Kaplan-Meier plotter were used for survival data of SLUG and QKI gene. We also mined the cBioPortal database for co-expression analysis of QKI and EMT markers. Our results suggested that patients with higher expression of SLUG and QKI showed shorter overall survival time. The mRNA level of SLUG and QKI were higher in ER negative, PR negative, ≤ 51 y, and TNBC patients. SLUG mRNA showed no survival significance, while higher QKI mRNA expression level was correlated with worse clinical outcome in Kaplan-Meier Plotter database. The cBioPortal database showed that QKI was correlated to SLUG as well as other EMT markers like TWIST2, VIM, and ZEB2. QKI was indicated to be a potential prognostic marker for BC patients, and combined expression of SLUG and QKI showed the best prognostic value. Co-expression analysis indicated that QKI was likely to have a correlation with SLUG and EMT.
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Affiliation(s)
- Siwen Gu
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Chengyu Chu
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Wanna Chen
- Department of General Surgery, The First Affiliated Hospital, Sun Yat-san UniversityGuangzhou, China
| | - Hong Ren
- Department of General Surgery, Qingdao Municipal HospitalQingdao, Shandong Province, China
| | - Yun Cao
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Xiaoyan Li
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Jing He
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Yiwei Wang
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Yiting Jin
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
| | - Xiuping Liu
- Department of Pathology, The Fifth People’s Hospital of Shanghai, Fudan UniversityShanghai, China
- Department of Pathology, School of Basic Medical Sciences, Fudan UniversityShanghai, China
| | - Qiang Zou
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai, China
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14
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Velasco MX, Kosti A, Penalva LOF, Hernández G. The Diverse Roles of RNA-Binding Proteins in Glioma Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1157:29-39. [DOI: 10.1007/978-3-030-19966-1_2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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15
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Xi Z, Wang P, Xue Y, Shang C, Liu X, Ma J, Li Z, Li Z, Bao M, Liu Y. Overexpression of miR-29a reduces the oncogenic properties of glioblastoma stem cells by downregulating Quaking gene isoform 6. Oncotarget 2018; 8:24949-24963. [PMID: 28212562 PMCID: PMC5421901 DOI: 10.18632/oncotarget.15327] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 01/23/2017] [Indexed: 11/25/2022] Open
Abstract
Glioblastoma is the most common type of malignant primary brain tumor and has high recurrence and lethality rates. Glioblastoma stem cells (GSCs), a subpopulation of glioblastoma cells, may promote rapid tumor recurrence and therapy resistance. Because altered microRNA (miR) expression in GSCs may lead to glioblastoma progression, we assessed the effects of miR-29a expression on the oncogenic behavior of GSCs. MiR-29a expression was lower in GSCs than non-GSCs, and overexpression of miR-29a in GSCs inhibited cell proliferation, migration and invasion, but promoted apoptosis. MiR-29a directly inhibited the expression of Quaking gene isoform 6 (QKI-6) by binding to its 3'-UTR, and thus inhibited GSC malignant behavior. In addition, Wilms' tumor 1-associating protein (WTAP) was identified as a downstream target of QKI-6. Overexpression of miR-29a in GSCs inhibited expression of WTAP and suppressed both phosphoinositide 3-kinase/AKT and extracellular signal-related kinase pathways by downregulating QKI-6, thereby inhibiting cell proliferation, migration, and invasion but promoting apoptosis. We have characterized a novel miR-29a/QKI-6/WTAP axis in GSCs, which may provide theoretical support for the treatment of glioblastoma with miR-29a agomirs.
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Affiliation(s)
- Zhuo Xi
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China.,Liaoning Research Center for Translational Medicine in Nervous System Disease, Shenyang 110004, People's Republic of China
| | - Ping Wang
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110122, People's Republic of China
| | - Yixue Xue
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110122, People's Republic of China
| | - Chao Shang
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110122, People's Republic of China
| | - Xiaobai Liu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China.,Liaoning Research Center for Translational Medicine in Nervous System Disease, Shenyang 110004, People's Republic of China
| | - Jun Ma
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110122, People's Republic of China
| | - Zhiqing Li
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110122, People's Republic of China
| | - Zhen Li
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China.,Liaoning Research Center for Translational Medicine in Nervous System Disease, Shenyang 110004, People's Republic of China
| | - Min Bao
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China.,Liaoning Research Center for Translational Medicine in Nervous System Disease, Shenyang 110004, People's Republic of China
| | - Yunhui Liu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China.,Liaoning Research Center for Translational Medicine in Nervous System Disease, Shenyang 110004, People's Republic of China
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16
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Farnsworth B, Peuckert C, Zimmermann B, Jazin E, Kettunen P, Emilsson LS. Gene Expression of Quaking in Sporadic Alzheimer's Disease Patients is Both Upregulated and Related to Expression Levels of Genes Involved in Amyloid Plaque and Neurofibrillary Tangle Formation. J Alzheimers Dis 2018; 53:209-19. [PMID: 27163826 PMCID: PMC4942724 DOI: 10.3233/jad-160160] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Quaking (QKI) is a gene exclusively expressed within glial cells. QKI has previously been implicated in various neurological disorders and diseases, including Alzheimer’s disease (AD), a condition for which increasing evidence suggests a central role of glia cells. The objective of the present study was to investigate the expression levels of QKI and three QKI isoforms (QKI5, QKI6, and QKI7) in AD. Genes that have previously been related to the ontogeny and progression of AD, specifically APP, PSEN1, PSEN2, and MAPT, were also investigated. A real-time PCR assay of 123 samples from human postmortem sporadic AD patients and control brains was performed. The expression values were analyzed with an analysis of covariance model and subsequent multiple regressions to explore the possibility of related expression values between QKI, QKI isoforms, and AD-related genes. Further, the sequences of AD-related genes were analyzed for the presence of QKI binding domains. QKI and all measured QKI isoforms were found to be significantly upregulated in AD samples, relative to control samples. However, APP, PSEN1, PSEN2, and MAPT were not found to be significantly different. QKI and QKI isoforms were found to be predictive for the variance of APP, PSEN1, PSEN2, and MAPT, and putative QKI binding sites suggests an interaction with QKI. Overall, these results implicate a possible role of QKI in AD, although the exact mechanism by which this occurs remains to be uncovered.
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Affiliation(s)
- Bryn Farnsworth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Christiane Peuckert
- Department of Neuroscience, Uppsala Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Bettina Zimmermann
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Elena Jazin
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Petronella Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Neuropathology, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Lina Sors Emilsson
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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17
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Yang H, Peng Z, Liang M, Zhang Y, Wang Y, Huang T, Jiang Y, Jiang B, Wang Y. The miR-17-92 cluster/QKI2/β-catenin axis promotes osteosarcoma progression. Oncotarget 2018; 9:25285-25293. [PMID: 29861871 PMCID: PMC5982768 DOI: 10.18632/oncotarget.23935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/30/2017] [Indexed: 02/07/2023] Open
Abstract
Quaking(QKI) is an RNA binding protein, and it has been shown to serve as a tumor suppressor. However, the expression and functions of QKI in osteosarcoma progression remain poorly understood. In this study, we aimed to explore the expression of QKI2 in osteosarcoma tissues and to determine the mechanisms underlying aberrant QKI2 expression and the effect of QKI2 on osteosarcoma progression. We found that QKI2 was significantly down-regulated in osteosarcoma tissues compared with adjacent normal bone tissues. Using a series of molecular biological techniques, we demonstrated that all members of the miR-17-92 cluster were up-regulated and contributed to the down-regulation of QKI2 expression in osteosarcoma. Functional examination showed that QKI2 inhibited the proliferation, migration and invasion of osteosarcoma cells via decreasing the expression of β-catenin. Conclusively, we revealed that the regulatory axis consisting of the miR-17-92 cluster/QKI2/β-catenin plays a crucial role in the development and progression of osteosarcoma.
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Affiliation(s)
- Hongbo Yang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Zhibin Peng
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Min Liang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yubo Zhang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yangyang Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Tianwen Huang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yudong Jiang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Bo Jiang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yansong Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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18
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Jain P, Fierst TM, Han HJ, Smith TE, Vakil A, Storm PB, Resnick AC, Waanders AJ. CRAF gene fusions in pediatric low-grade gliomas define a distinct drug response based on dimerization profiles. Oncogene 2017; 36:6348-6358. [PMID: 28806393 PMCID: PMC5680138 DOI: 10.1038/onc.2017.276] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 06/26/2017] [Accepted: 07/05/2017] [Indexed: 01/07/2023]
Abstract
Pediatric low-grade gliomas (PLGGs) are commonly associated with BRAF gene fusions that aberrantly activate the mitogen-activated protein kinase (MAPK) signaling pathway. This has led to PLGG clinical trials utilizing RAF- and MAPK pathway-targeted therapeutics. Whole-genome profiling of PLGGs has also identified rare gene fusions involving another RAF isoform, CRAF/RAF1, in PLGGs and cancers occuring in adults. Whereas BRAF fusions primarily dysregulate MAPK signaling, the CRAF fusions QKI-RAF1 and SRGAP3-RAF1 aberrantly activate both the MAPK and phosphoinositide-3 kinase/mammalian target of rapamycin (PI3K/mTOR) signaling pathways. Although ATP-competitive, first-generation RAF inhibitors (vemurafenib/PLX4720, RAFi) cause paradoxical activation of the MAPK pathway in BRAF-fusion tumors, inhibition can be achieved with ‘paradox breaker’ RAFi, such as PLX8394. Here we report that, unlike BRAF fusions, CRAF fusions are unresponsive to both generations of RAFi, vemurafenib and PLX8394, highlighting a distinct responsiveness of CRAF fusions to clinically relevant RAFi. Whereas PLX8394 decreased BRAF-fusion dimerization, CRAF-fusion dimerization is unaffected primarily because of robust protein–protein interactions mediated by the N-terminal non-kinase fusion partner, such as QKI. The pan-RAF dimer inhibitor, LY3009120, could suppress CRAF-fusion oncogenicity by inhibiting dimer-mediated signaling. In addition, as CRAF fusions activate both the MAPK and PI3K/mTOR signaling pathways, we identify combinatorial inhibition of the MAPK/mTOR pathway as a potential therapeutic strategy for CRAF-fusion-driven tumors. Overall, we define a mechanistic distinction between PLGG-associated BRAF- and CRAF/RAF1 fusions in response to RAFi, highlighting the importance of molecularly classifying PLGG patients for targeted therapy. Furthermore, our study uncovers an important contribution of the non-kinase fusion partner to oncogenesis and potential therapeutic strategies against PLGG-associated CRAF fusions and possibly pan-cancer CRAF fusions.
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Affiliation(s)
- P Jain
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Cell and Molecular Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - T M Fierst
- Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Neurosurgery, Temple University School of Medicine, Philadelphia, PA, USA
| | - H J Han
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - T E Smith
- Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - A Vakil
- Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - P B Storm
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Center of Childhood Cancer Research, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Center for Data Driven Discovery in Biomedicine (D3b), The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - A C Resnick
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Division of Neurosurgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Center of Childhood Cancer Research, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Center for Data Driven Discovery in Biomedicine (D3b), The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - A J Waanders
- Center of Childhood Cancer Research, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Center for Data Driven Discovery in Biomedicine (D3b), The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Division of Oncology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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19
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Bin JM, Harris SN, Kennedy TE. The oligodendrocyte-specific antibody 'CC1' binds Quaking 7. J Neurochem 2016; 139:181-186. [PMID: 27454326 DOI: 10.1111/jnc.13745] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 06/22/2016] [Accepted: 07/18/2016] [Indexed: 11/29/2022]
Abstract
The mouse monoclonal antibody marketed as anti-adenomatous polyposis coli clone CC1, often referred to as CC1, is the antibody most commonly used to specifically label mature oligodendrocytes without labeling myelin. Previous studies have shown that despite being raised against adenomatous polyposis coli, this antibody binds another unknown antigen. We show that the CC1 antibody binds Quaking 7, an RNA-binding protein that is highly up-regulated in myelinating oligodendrocytes in the central nervous system. The monoclonal antibody anti-adenomatous polyposis coli (APC) clone CC1, is the antibody most commonly used to specifically label the cell bodies of mature oligodendrocytes. Despite being raised against APC, previous studies showed this antibody binds another unknown antigen. We show that the CC1 antibody binds Quaking (QKI) 7, an RNA-binding protein which is highly up-regulated in myelinating oligodendrocytes.
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Affiliation(s)
- Jenea M Bin
- Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Stephanie N Harris
- Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Timothy E Kennedy
- Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada.
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20
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Darbelli L, Richard S. Emerging functions of the Quaking RNA-binding proteins and link to human diseases. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:399-412. [PMID: 26991871 DOI: 10.1002/wrna.1344] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/23/2016] [Accepted: 02/01/2016] [Indexed: 01/16/2023]
Abstract
RNA-binding proteins (RBPs) are essential players in RNA metabolism including key cellular processes from pre-mRNA splicing to mRNA translation. The K homology-type QUAKING RBP is emerging as a vital factor for oligodendrocytes, monocytes/macrophages, endothelial cell, and myocyte function. Interestingly, the qkI gene has now been identified as the culprit gene for a patient with intellectual disabilities and is translocated in a pediatric ganglioglioma as a fusion protein with MYB. In this review, we will focus on the emerging discoveries of the QKI proteins as well as highlight the recent advances in understanding the role of QKI in human disease pathology including myelin disorders, schizophrenia and cancer. WIREs RNA 2016, 7:399-412. doi: 10.1002/wrna.1344 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Lama Darbelli
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Canada, H3T 1E2
| | - Stéphane Richard
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Canada, H3T 1E2
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Radomska KJ, Sager J, Farnsworth B, Tellgren-Roth Å, Tuveri G, Peuckert C, Kettunen P, Jazin E, Emilsson LS. Characterization and Expression of the Zebrafish qki Paralogs. PLoS One 2016; 11:e0146155. [PMID: 26727370 PMCID: PMC4699748 DOI: 10.1371/journal.pone.0146155] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 12/13/2015] [Indexed: 11/21/2022] Open
Abstract
Quaking (QKI) is an RNA-binding protein involved in post-transcriptional mRNA processing. This gene is found to be associated with several human neurological disorders. Early expression of QKI proteins in the developing mouse neuroepithelium, together with neural tube defects in Qk mouse mutants, suggest the functional requirement of Qk for the establishment of the nervous system. As a knockout of Qk is embryonic lethal in mice, other model systems like the zebrafish could serve as a tool to study the developmental functions of qki. In the present study we sought to characterize the evolutionary relationship and spatiotemporal expression of qkia, qki2, and qkib; zebrafish homologs of human QKI. We found that qkia is an ancestral paralog of the single tetrapod Qk gene that was likely lost during the fin-to-limb transition. Conversely, qkib and qki2 are orthologs, emerging at the root of the vertebrate and teleost lineage, respectively. Both qki2 and qkib, but not qkia, were expressed in the progenitor domains of the central nervous system, similar to expression of the single gene in mice. Despite having partially overlapping expression domains, each gene has a unique expression pattern, suggesting that these genes have undergone subfunctionalization following duplication. Therefore, we suggest the zebrafish could be used to study the separate functions of qki genes during embryonic development.
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Affiliation(s)
- Katarzyna J. Radomska
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Jonathan Sager
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Bryn Farnsworth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Åsa Tellgren-Roth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Giulia Tuveri
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Christiane Peuckert
- Department of Neuroscience, Uppsala Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Petronella Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Neuropathology, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Elena Jazin
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Lina S. Emilsson
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
- * E-mail:
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Zhao Y, Zhang G, Wei M, Lu X, Fu H, Feng F, Wang S, Lu W, Wu N, Lu Z, Yuan J. The tumor suppressing effects of QKI-5 in prostate cancer: a novel diagnostic and prognostic protein. Cancer Biol Ther 2013; 15:108-18. [PMID: 24153116 DOI: 10.4161/cbt.26722] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
In recent years, the RNA-binding protein quaking 5 (QKI-5) has been recognized as a novel tumor suppressor in many cancers. To date, no studies have examined the role of QKI-5 in prostate cancer. The present study was designed to elucidate the correlation of QKI-5 expression with the clinical pathological features and prognosis of prostate cancer. In an overwhelming majority of the 184 cases of prostate cancer samples analyzed, the QKI-5 expression was significantly decreased, which was largely due to the high promoter methylation levels. Using lentiviral vectors, we established two stable prostate cancer cell lines with altered QKI-5 expression, including a QKI-5 overexpressing PC3 cell line and a DU145 cell line with knocked-down QKI-5 expression. The effects of the lentiviral-mediated QKI-5 knockdown on the PC3 cells and DU145 cells were assessed by cell growth curves, flow cytometry (FCM), and an invasion assay. The PC3 cells were transplanted into nude mice, and then, the tumor growth curves and TUNEL staining were determined. These results demonstrated that QKI-5 was highly expressed in benign prostatic hyperplasia (BPH) tissues but not in carcinomatous tissues and that QKI-5 effectively inhibited prostate cancer cell proliferation in vitro and in vivo. In addition, the decrease in QKI-5 expression was closely correlated with the prostate cancer Gleason score, poor differentiation, degree of invasion, lymph node metastasis, distant metastasis, TNM grading, and poor survival. These results indicate that the QKI-5 expression may be a novel, independent factor in the prognosis of prostate cancer patients.
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Affiliation(s)
- Yi Zhao
- Department of Urology; Xijing Hospital; Fourth Military Medical University; Xi'an, PR China; Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Gen Zhang
- Department of Urology; Xijing Hospital; Fourth Military Medical University; Xi'an, PR China
| | - Mengying Wei
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Xiaozhao Lu
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Hanyan Fu
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Feixue Feng
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Shan Wang
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Wei Lu
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Ning Wu
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Zifan Lu
- Department of Biochemistry and Molecular Biology; State Key Laboratory of Cancer Biology; Fourth Military Medical University; Xi'an, PR China
| | - Jianlin Yuan
- Department of Urology; Xijing Hospital; Fourth Military Medical University; Xi'an, PR China
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Ji S, Ye G, Zhang J, Wang L, Wang T, Wang Z, Zhang T, Wang G, Guo Z, Luo Y, Cai J, Yang JY. miR-574-5p negatively regulates Qki6/7 to impact β-catenin/Wnt signalling and the development of colorectal cancer. Gut 2013; 62:716-26. [PMID: 22490519 PMCID: PMC3618686 DOI: 10.1136/gutjnl-2011-301083] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Deficiency or reduced expression of signal transduction and activation of RNA family protein Quaking (Qki) is associated with developmental defects in neural and vascular tissues and the development of debilitating human diseases including colorectal cancer (CRC). However, the mechanisms underlying the aberrant downregulation or deficiency of Qki were uncertain. DESIGN Expression of miR-574-5p, Qki5/6/7/7b splicing variants, β-catenin and p27(Kip1) was determined in mouse and human CRC cells and tissues to investigate the post-transcriptional regulation of Qki isoforms by miR-574-5p and its impact on β-catenin/p27(Kip1) signalling, cell cycle progression, proliferation, migration, invasion and tumour growth. RESULTS In the CRC tissues of C57BL/6-Apc(min/+) mice, miR-574-5p was found to be significantly upregulated and negatively correlated with the expression of Qki but positively correlated with the expression of β-catenin. In mouse and human CRC cells, miR-574-5p was shown to regulate Qki isoforms (Qki6/7 in particular) post-transcriptionally and caused altered expression in β-catenin and p27(Kip1) , increased proliferation, migration and invasion and decreased differentiation and cell cycle exit. Furthermore, in clinical CRC tissues, miR-574-5p was shown to be greatly upregulated and inversely correlated with the expression of Qkis. Finally, inhibition of miR-574-5p was shown to suppress the growth of tumours in the nude mice. CONCLUSIONS Together, these novel findings suggest that miR-574-5p is a potent ribo-regulator for Qkis and that aberrant miR-574-5p upregulation can be oncogenic.
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Affiliation(s)
- Shunlong Ji
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Gengtai Ye
- Department of Surgical Oncology the First Affiliated Hospital of Xiamen University and Xiamen Cancer Center, Xiamen, People's Republic of China
| | - Jun Zhang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Linpei Wang
- Department of Surgical Oncology the First Affiliated Hospital of Xiamen University and Xiamen Cancer Center, Xiamen, People's Republic of China
| | - Tao Wang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Zhen Wang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Tiantian Zhang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Guanghui Wang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Zongsheng Guo
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China
| | - Yu Luo
- School of Nursing, the Third Military Medical University, Chongqing, People's Republic of China
| | - Jianchun Cai
- Department of Surgical Oncology the First Affiliated Hospital of Xiamen University and Xiamen Cancer Center, Xiamen, People's Republic of China
| | - James Y Yang
- State Key Laboratory of Cellular Stress Biology and Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiamen, People's Republic of China,Fujian Provincial Transgenic Core, Xiamen University Laboratory Animal Center, Xiamen, People's Republic of China
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Ali M, Broadhurst RW. Solution structure of the QUA1 dimerization domain of pXqua, the Xenopus ortholog of Quaking. PLoS One 2013; 8:e57345. [PMID: 23520467 PMCID: PMC3592866 DOI: 10.1371/journal.pone.0057345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 01/21/2013] [Indexed: 11/19/2022] Open
Abstract
The STAR protein family member Quaking is essential for early development in vertebrates. For example, in oligodendrocyte cells it regulates the splicing, localization, translation and lifetime of a set of mRNAs that code for crucial components of myelin. The Quaking protein contains three contiguous conserved regions: a QUA1 oligomerization element, followed by a single-stranded RNA binding motif comprising the KH and QUA2 domains. An embryonic lethal point mutation in the QUA1 domain, E48G, is known to affect both the aggregation state and RNA-binding properties of the murine Quaking ortholog (QKI). Here we report the NMR solution structure of the QUA1 domain from the Xenopus laevis Quaking ortholog (pXqua), which forms a dimer composed of two perpendicularly docked α-helical hairpin motifs. Size exclusion chromatography studies of a range of mutants demonstrate that the dimeric state of the pXqua QUA1 domain is stabilized by a network of interactions between side-chains, with significant roles played by an intra-molecular hydrogen bond between Y41 and E72 (the counterpart to QKI E48) and an inter-protomer salt bridge between E72 and R67. These results are compared with recent structural and mutagenesis studies of QUA1 domains from the STAR family members QKI, GLD-1 and Sam68.
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Affiliation(s)
- Muzaffar Ali
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - R. William Broadhurst
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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Preparation and characterizations of polyclonal antibodies against STAR protein QKI7b. Appl Biochem Biotechnol 2013; 169:2273-80. [PMID: 23440637 DOI: 10.1007/s12010-012-0081-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 12/27/2012] [Indexed: 01/05/2023]
Abstract
Quaking (QKI) proteins are important regulators of RNA metabolism and cellular signal transduction. Recent studies have shown that isoforms of QKI proteins, which include QKI5/6/7/7b in human cells, play important roles in the development of neurological diseases and human cancers. In comparison with QKI5/6/7, however, there are little data on QKI7b due to lack of specific antibodies. Here, we reported the preparation and initial characterizations of polyclonal antibodies against human QKI7b. Utilizing a chemically synthesized C-terminal peptide fragment of human QKI7b, we raised two preparations of rabbit antiserum. We found that these antibodies were able to recognize human QKI7b, but not QKI5/6/7. Our immunofluorescence staining showed that in LO2 hepatocytes, QKI7b localizes predominantly in the perinuclear cytoplasm and less abundantly in the nucleus. In clinical samples, we showed that like QKI5/6/7 proteins, QKI7b protein was also significantly downregulated in most human colorectal cancer tissues. These antibodies, therefore, might be useful in future functional studies of QKI7b.
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Radomska KJ, Halvardson J, Reinius B, Lindholm Carlström E, Emilsson L, Feuk L, Jazin E. RNA-binding protein QKI regulates Glial fibrillary acidic protein expression in human astrocytes. Hum Mol Genet 2013; 22:1373-82. [PMID: 23321059 DOI: 10.1093/hmg/dds553] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Linkage, association and expression studies previously pointed to the human QKI, KH domain containing, RNA-binding (QKI) as a candidate gene for schizophrenia. Functional studies of the mouse orthologue Qk focused mainly on its role in oligodendrocyte development and myelination, while its function in astroglia remained unexplored. Here, we show that QKI is highly expressed in human primary astrocytes and that its splice forms encode proteins targeting different subcellular localizations. Uncovering the role of QKI in astrocytes is of interest in light of growing evidence implicating astrocyte dysfunction in the pathogenesis of several disorders of the central nervous system. We selectively silenced QKI splice variants in human primary astrocytes and used RNA sequencing to identify differential expression and splice variant composition at the genome-wide level. We found that an mRNA expression of Glial fibrillary acidic protein (GFAP), encoding a major component of astrocyte intermediate filaments, was down-regulated after QKI7 splice variant silencing. Moreover, we identified a potential QKI-binding site within the 3' untranslated region of human GFAP. This sequence was not conserved between mice and humans, raising the possibility that GFAP is a target for QKI in humans but not rodents. Haloperidol treatment of primary astrocytes resulted in coordinated increases in QKI7 and GFAP expression. Taken together, our results provide the first link between QKI and GFAP, two genes with alterations previously observed independently in schizophrenic patients. Our findings for QKI, together with its well-known role in myelination, suggest that QKI is a hub regulator of glia function in humans.
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Affiliation(s)
- Katarzyna J Radomska
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala,Sweden
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The QKI-5 and QKI-6 RNA binding proteins regulate the expression of microRNA 7 in glial cells. Mol Cell Biol 2013; 33:1233-43. [PMID: 23319046 DOI: 10.1128/mcb.01604-12] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The quaking (qkI) gene encodes 3 major alternatively spliced isoforms that contain unique sequences at their C termini dictating their cellular localization. QKI-5 is predominantly nuclear, whereas QKI-6 is distributed throughout the cell and QKI-7 is cytoplasmic. The QKI isoforms are sequence-specific RNA binding proteins expressed mainly in glial cells modulating RNA splicing, export, and stability. Herein, we identify a new role for the QKI proteins in the regulation of microRNA (miRNA) processing. We observed that small interfering RNA (siRNA)-mediated QKI depletion of U343 glioblastoma cells leads to a robust increase in miR-7 expression. The processing from primary to mature miR-7 was inhibited in the presence QKI-5 and QKI-6 but not QKI-7, suggesting that the nuclear localization plays an important role in the regulation of miR-7 expression. The primary miR-7-1 was bound by the QKI isoforms in a QKI response element (QRE)-specific manner. We observed that the pri-miR-7-1 RNA was tightly bound to Drosha in the presence of the QKI isoforms, and this association was not observed in siRNA-mediated QKI or Drosha-depleted U343 glioblastoma cells. Moreover, the presence of the QKI isoforms led to an increase presence of pri-miR-7 in nuclear foci, suggesting that pri-miR-7-1 is retained in the nucleus by the QKI isoforms. miR-7 is known to target the epidermal growth factor (EGF) receptor (EGFR) 3' untranslated region (3'-UTR), and indeed, QKI-deficient U343 cells had reduced EGFR expression and decreased ERK activation in response to EGF. Elevated levels of miR-7 are associated with cell cycle arrest, and it was observed that QKI-deficient U343 that harbor elevated levels of miR-7 exhibited defects in cell proliferation that were partially rescued by the addition of a miR-7 inhibitor. These findings suggest that the QKI isoforms regulate glial cell function and proliferation by regulating the processing of certain miRNAs.
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Chen AJ, Paik JH, Zhang H, Shukla SA, Mortensen R, Hu J, Ying H, Hu B, Hurt J, Farny N, Dong C, Xiao Y, Wang YA, Silver PA, Chin L, Vasudevan S, Depinho RA. STAR RNA-binding protein Quaking suppresses cancer via stabilization of specific miRNA. Genes Dev 2012; 26:1459-72. [PMID: 22751500 DOI: 10.1101/gad.189001.112] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Multidimensional cancer genome analysis and validation has defined Quaking (QKI), a member of the signal transduction and activation of RNA (STAR) family of RNA-binding proteins, as a novel glioblastoma multiforme (GBM) tumor suppressor. Here, we establish that p53 directly regulates QKI gene expression, and QKI protein associates with and leads to the stabilization of miR-20a; miR-20a, in turn, regulates TGFβR2 and the TGFβ signaling network. This pathway circuitry is substantiated by in silico epistasis analysis of its components in the human GBM TCGA (The Cancer Genome Atlas Project) collection and by their gain- and loss-of-function interactions in in vitro and in vivo complementation studies. This p53-QKI-miR-20a-TGFβ pathway expands our understanding of the p53 tumor suppression network in cancer and reveals a novel tumor suppression mechanism involving regulation of specific cancer-relevant microRNAs.
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Affiliation(s)
- An-Jou Chen
- Belfer Institute for Applied Cancer Science, Harvard Medical School, Boston, Massachusetts 02115, USA
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Bian Y, Wang L, Lu H, Yang G, Zhang Z, Fu H, Lu X, Wei M, Sun J, Zhao Q, Dong G, Lu Z. Downregulation of tumor suppressor QKI in gastric cancer and its implication in cancer prognosis. Biochem Biophys Res Commun 2012; 422:187-93. [PMID: 22569043 DOI: 10.1016/j.bbrc.2012.04.138] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 04/25/2012] [Indexed: 12/31/2022]
Abstract
Gastric cancer (GC) is the fourth most common cancer and second leading cause of cancer-related death worldwide. RNA-binding protein Quaking (QKI) is a newly identified tumor suppressor in multiple cancers, while its role in GC is largely unknown. Our study here aimed to clarify the relationship between QKI expression with the clinicopathologic characteristics and the prognosis of GC. In the 222 GC patients' specimens, QKI expression was found to be significantly decreased in most of the GC tissues, which was largely due to promoter hypermethylation. QKI overexpression reduced the proliferation ability of GC cell line in vitro study. In addition, the reduced QKI expression correlated well with poor differentiation status, depth of invasion, gastric lymph node metastasis, distant metastasis, advanced TNM stage, and poor survival. Multivariate analysis showed QKI expression was an independent prognostic factor for patient survival.
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Affiliation(s)
- Yongqian Bian
- The State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University, Xi'an 710032, PR China
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Iwata K, Matsuzaki H, Manabe T, Mori N. Altering the expression balance of hnRNP C1 and C2 changes the expression of myelination-related genes. Psychiatry Res 2011; 190:364-6. [PMID: 21684615 DOI: 10.1016/j.psychres.2011.05.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 05/12/2011] [Accepted: 05/27/2011] [Indexed: 10/18/2022]
Abstract
The expression level of hnRNP C1/C2 protein has been reported to be significantly decreased in the post-mortem brain of schizophrenic patients. In this study, we investigated whether overexpression of the hnRNP C variants hnRNP C1 and C2 changed the expression of myelination-related genes in the human neuroblastoma cell line SK-N-SH. In both hnRNP C1- and C2-overexpressing cells, the expression of quaking (QKI)-6 and QKI-7 significantly increased or decreased compared to the control, respectively. Intriguingly, QKI-5 and myelin basic protein were markedly up- or down-regulated by overexpressing hnRNP C2, respectively. Our findings are the first to demonstrate distinct functions of hnRNP C1 and C2, and may be helpful in understanding the functions of these molecules. These findings indicate that altered expression levels of hnRNP C in the brain of patients with schizophrenia could be involved in the pathophysiology of this disease through alteration of the QKI isoform and myelin basic protein expression.
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Affiliation(s)
- Keiko Iwata
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan.
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Loss of p53 in quaking viable mice leads to Purkinje cell defects and reduced survival. Sci Rep 2011; 1:84. [PMID: 22355603 PMCID: PMC3239166 DOI: 10.1038/srep00084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 08/18/2011] [Indexed: 11/08/2022] Open
Abstract
The qk(v) mutation is a one megabase deletion resulting in abnormal expression of the qkI gene. qk(v) mice exhibit hypomyelination of the central nervous system and display rapid tremors and seizures as adults. The qkI locus on 6q26-27 has also been implicated as a candidate tumor suppressor gene as the qkI locus maps to a region of genetic instability in Glioblastoma Multiforme (GBM), an aggressive brain tumor of astrocytic lineage. As GBM frequently harbors mutations affecting p53, we crossbred qk(v) and p53 mutant mice to examine whether qk(v) mice on a p53(-/-) background have an increased incidence of GBM. qk(v) (/v); p53(-/-) mice had a reduced survival rate compared to p53(-/-) littermates, and the cause of death of the majority of the mice remains unknown. In addition, immunohistochemistry revealed Purkinje cell degeneration in the cerebellum. These results suggest that p53 and qkI are genetically linked for neuronal maintenance and survival.
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Yang G, Fu H, Zhang J, Lu X, Yu F, Jin L, Bai L, Huang B, Shen L, Feng Y, Yao L, Lu Z. RNA-binding protein quaking, a critical regulator of colon epithelial differentiation and a suppressor of colon cancer. Gastroenterology 2010; 138:231-40.e1-5. [PMID: 19686745 PMCID: PMC2847771 DOI: 10.1053/j.gastro.2009.08.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 06/20/2009] [Accepted: 08/06/2009] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Colon cancer is one of the best understood neoplasms from a genetic perspective, yet it remains the second most common cause of cancer-related death. Post-transcriptional regulation mediated by RNA-binding proteins or microRNAs coordinately targets multiple genes, holding promise involved in colon cancer initiation and development. Here we studied the role of RNA-binding protein quaking (QKI) in colon cancer. METHODS We observed the expression pattern of QKI in normal colon and colon cancers through reverse-transcription polymerase chain reaction and Western blot. Bisulfite sequencing and methylation-specific PCR were applied for QKI promoter methylation analysis. We used enterocyte differentiation markers and soft agar assay to test the role of QKI in colon differentiation and colon cancer development. 3' Untranslated region (UTR) reporter assay and RNA-immunoprecipitation were used to confirm the interaction between QKI and beta-catenin or p27. RESULTS QKI is significantly down-regulated and even absent in some colon cancers, which is at least partially because of the promoter hypermethylation. Forced expression of QKI in the colon cancer cells increased the expression of enterocyte differentiation marker intestinal alkaline phosphatase and lactase, together with the enhancement of p27Kip1 protein level, and membrane localized beta-catenin. Finally, QKI overexpression reduced the proliferation and tumorigenesis ability. CONCLUSIONS Our study establishes that QKI functions as a principal regulator in the differentiation of colon epithelium and a suppressor of carcinogenesis through coordinately targeting multiple genes associated with cell growth and differentiation, whose deregulation by methylation is involved in colon cancer onset and progress.
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Affiliation(s)
- Guodong Yang
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Haiyan Fu
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Jie Zhang
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Xiaozhao Lu
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Fang Yu
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Liang Jin
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Liyuan Bai
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Bo Huang
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Lan Shen
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University
| | - Yue Feng
- Department of Pharmacology, Emory University, Atlanta, GA, 30322
| | - Libo Yao
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University,To whom correspondence should be addressed: Z Lu, NO.17 Changlexi Road, the Fourth Military Medical University, 710032 Xi’an PR China, , tel: 86-29-84774513, fax 86-29-84773947. L Yao, NO.17 Changlexi Road, the Fourth Military Medical University, 710032 Xi’an PR China, , tel: 86-29-84774513, fax 86-29-84773947
| | - Zifan Lu
- Department of Biochemistry and Molecular Biology, the State Key Laboratory of Cancer Biology, the Fourth Military Medical University,To whom correspondence should be addressed: Z Lu, NO.17 Changlexi Road, the Fourth Military Medical University, 710032 Xi’an PR China, , tel: 86-29-84774513, fax 86-29-84773947. L Yao, NO.17 Changlexi Road, the Fourth Military Medical University, 710032 Xi’an PR China, , tel: 86-29-84774513, fax 86-29-84773947
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Klempan TA, Ernst C, Deleva V, Labonte B, Turecki G. Characterization of QKI gene expression, genetics, and epigenetics in suicide victims with major depressive disorder. Biol Psychiatry 2009; 66:824-31. [PMID: 19545858 DOI: 10.1016/j.biopsych.2009.05.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 05/03/2009] [Accepted: 05/05/2009] [Indexed: 01/09/2023]
Abstract
BACKGROUND A number of studies have suggested deficits in myelination and glial gene expression in different psychiatric disorders. We examined the brain expression and genetic/epigenetic regulation of QKI, an oligodendrocyte-specific RNA binding protein important for cell development and myelination. METHODS The microarray-based expression of QKI was evaluated in cortical and subcortical brain regions from suicide victims with a diagnosis of major depression (n = 16) and control subjects (n = 13). These findings were also assessed with a real-time (quantitative polymerase chain reaction [qPCR]) approach, with QKI protein levels evaluated through immunoblotting. Identification of a QKI promoter sequence was then used to examine genetic and epigenetic variation at the QKI locus. RESULTS The messenger RNA (mRNA) levels of multiple transcripts of QKI were evaluated on Affymetrix microarrays, revealing significant reductions in 11 cortical regions and the hippocampus and amygdala of suicide victims compared with control subjects. Microarray findings were confirmed by qPCR, and reduced expression of QKI protein was identified in orbitofrontal cortex. Analysis of promoter variation and methylation state in a subset of individuals did not identify differences at the genetic or epigenetic level between depressed suicide victims and control subjects. CONCLUSIONS The observation of consistent reductions in multiple isoforms of QKI mRNA in depressed suicide victims supports the growing body of evidence for a role of myelination-related deficits in the etiology of psychiatric disorders. A specific role of QKI in this process is implied by its reduced expression and known interactions with genes involved in oligodendrocyte determination; however, QKI gene variation responsible for these changes remains to be identified.
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Affiliation(s)
- Timothy A Klempan
- McGill Group for Suicide Studies, Douglas Hospital, McGill University, Montreal, Quebec, Canada
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Huang K, Tang W, Xu Z, Li Z, He Z, Tang R, Che R, Xu Y, Li X, Feng G, He L, Shi Y. No association found between the promoter variations of QKI and schizophrenia in the Chinese population. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:33-6. [PMID: 18938205 DOI: 10.1016/j.pnpbp.2008.09.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 09/09/2008] [Accepted: 09/30/2008] [Indexed: 10/21/2022]
Abstract
BACKGROUND Schizophrenia is a chronic psychiatric disorder with a strong genetic component. Several recent published studies have reported that the mRNA expression level of quaking homolog, KH domain RNA binding (QKI) is down regulated in individuals diagnosed with schizophrenia. METHODS We were interested in the genetic variants around the promoter region of QKI and selected seven variants in this region, namely rs4263561, rs3904720, rs387504, rs3763197, rs7772756, rs7758706 and rs4709716. For the study we recruited 288 individuals diagnosed with schizophrenia and 288 control subjects. All the recruits were from Shanghai and were Han Chinese in origin. RESULTS No individual SNP nor any haplotype was found to be associated with schizophrenia. CONCLUSIONS These results suggest that the variants within the promoter region of QKI gene are unlikely to play a major role in susceptibility to schizophrenia in the Chinese population.
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Affiliation(s)
- Ke Huang
- Institute of Neuropsychiatric Science and Systems Biological Medicine, Shanghai Jiao Tong University, China
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37
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Klempan TA, Sequeira A, Canetti L, Lalovic A, Ernst C, ffrench-Mullen J, Turecki G. Altered expression of genes involved in ATP biosynthesis and GABAergic neurotransmission in the ventral prefrontal cortex of suicides with and without major depression. Mol Psychiatry 2009; 14:175-89. [PMID: 17938633 DOI: 10.1038/sj.mp.4002110] [Citation(s) in RCA: 213] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The prefrontal cortex is believed to play a major role in depression and suicidal behavior through regulation of cognition, memory, recognition of emotion, and anxiety-like states, with numerous post-mortem studies documenting a prefrontal serotonergic dysregulation considered to be characteristic of depressive psychopathology. This study was carried out to detect changes in gene expression associated with both suicide and major depression using oligonucleotide microarrays (Affymetrix HG-U133 chip set) summarizing expression patterns in primarily ventral regions of the prefrontal cortex (BA44, 45, 46 and 47). A total of 37 male subjects were included in this study, of which 24 were suicides (depressed suicides=16, nondepressed suicides=8) and 13 were matched controls. All subjects were clinically characterized by means of psychological autopsies using structured interviews. Unique patterns of differential expression were validated in each of the cortical regions evaluated, with group-specific changes highlighting the involvement of several key neurobiological pathways that have been implicated in both suicide and depression. An overrepresentation of factors involved in cell cycle control and cell division (BA44), transcription (BA44 and 47) and myelination (BA46) was seen in gene ontology analysis of differentially expressed genes, which also highlights changes in the expression of genes involved in ATP biosynthesis and utilization across all areas. Gene misexpression in BA46 was most pronounced between the two suicide groups, with many significant genes involved in GABAergic neurotransmission. The pronounced misexpression of genes central to GABAergic signaling and astrocyte/oligodendrocyte function provides further support for a central glial pathology in depression and suicidal behavior.
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Affiliation(s)
- T A Klempan
- McGill Group for Suicide Studies, Douglas Hospital, McGill University, Montreal, QC, Canada
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38
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Bockbrader K, Feng Y. Essential function, sophisticated regulation and pathological impact of the selective RNA-binding protein QKI in CNS myelin development. FUTURE NEUROLOGY 2008; 3:655-668. [PMID: 19727426 DOI: 10.2217/14796708.3.6.655] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The selective RNA-binding protein QKI play a key role in advancing oligodendrocyte-dependent myelination, which is essential for the function and development of the CNS. The emerging evidence that QKI abnormalities are associated with schizophrenia and may underlie myelin impairment in this devastating disease has greatly increased interest in understanding the function of QKI. Despite the discovery of the biochemical basis for QKI-RNA interaction, a comprehensive model is currently missing regarding how QKI regulates its mRNA ligands to promote normal myelinogenesis and how deficiency of the QKI pathway is involved in the pathogenesis of human diseases that affect CNS myelin. In this review, we will focus on the role of QKI in regulating distinct mRNA targets at critical developmental steps to promote oligodendrocyte differentiation and myelin formation. In addition, we will discuss molecular mechanisms that control QKI expression and activity during normal myelinogenesis as well as the pathological impact of QKI deficiency in dysmyelination mutant animals and in human myelin disorders.
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Affiliation(s)
- Katrina Bockbrader
- Department of Pharmacology, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA 30322, USA, Tel.: +1 404 727 0351, ,
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39
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Karoutzou G, Emrich HM, Dietrich DE. The myelin-pathogenesis puzzle in schizophrenia: a literature review. Mol Psychiatry 2008; 13:245-60. [PMID: 17925796 DOI: 10.1038/sj.mp.4002096] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Schizophrenia is a serious and disabling mental disorder with symptoms such as auditory hallucinations, disordered thinking and delusions, avolition, anhedonia, blunted affect and apathy. In this review article we seek to present the current scientific findings from linkage studies and susceptible genes and the pathophysiology of white matter in schizophrenia. The article has been reviewed in two parts. The first part deals with the linkage studies and susceptible genes in schizophrenia in order to have a clear-cut picture of the involvement of chromosomes and their genes in schizophrenia. The genetic linkage results seem to be replicated in some cases but in others are not. From these results, we cannot draw a fine map to a single locus or gene, leading to the conclusion that schizophrenia is not caused by a single factor/gene. In the second part of the article we present the oligodendrocyte-related genes that are associated with schizophrenia, as we hypothesize a potential role of oligodendrocyte-related genes in the pathology of the disorder.
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Affiliation(s)
- G Karoutzou
- Department of Clinical Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany
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40
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Chénard CA, Richard S. New implications for the QUAKING RNA binding protein in human disease. J Neurosci Res 2008; 86:233-42. [PMID: 17787018 DOI: 10.1002/jnr.21485] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The use of spontaneously occurring mouse models has proved to be a valuable tool throughout the years to delineate the signals required for nervous system development. This is especially true in the field of myelin biology, with a large number of different models available. The quaking viable mouse models dysmyelination in the nervous system and links the QUAKING RNA binding proteins to myelination and cell fate decisions. In this Mini-Review, we highlight the biological functions attributed to this KH-type RNA binding protein and the recent achievements linking it to human disorders.
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Affiliation(s)
- Carol Anne Chénard
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research and Department of Oncology, McGill University, Montréal, Québec, Canada
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41
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Åberg K, Saetre P, Jareborg N, Jazin E. Human QKI, a potential regulator of mRNA expression of human oligodendrocyte-related genes involved in schizophrenia. Proc Natl Acad Sci U S A 2006; 103:7482-7. [PMID: 16641098 PMCID: PMC1464365 DOI: 10.1073/pnas.0601213103] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The quaking viable mouse mutation (qk(v)) is a deletion including the 5' regulatory region of the quaking gene (Qki), which causes body tremor and severe dysmyelination in mouse. The function of the human quaking gene, called quaking homolog KH domain RNA-binding (mouse) (QKI), is not well known. We have previously shown that QKI is a new candidate gene for schizophrenia. Here we show that human QKI mRNA levels can account for a high proportion (47%) of normal interindividual mRNA expression variation (and covariation) of six oligodendrocyte-related genes (PLP1, MAG, MBP, TF, SOX10, and CDKN1B) in 55 human brain autopsy samples from individuals without psychiatric diagnoses. In addition, the tightly coexpressed myelin-related genes (PLP1, MAG, and TF) have decreased mRNA levels in 55 schizophrenic patients, as compared with 55 control individuals, and most of this difference (68-96%) can be explained by variation in the relative mRNA levels of QKI-7kb, the same QKI splice variant previously shown to be down-regulated in patients with schizophrenia. Taken together, our results suggest that QKI levels may regulate oligodendrocyte differentiation and maturation in human brain, in a similar way as in mouse. Moreover, we hypothesize that previously observed decreased activity of myelin-related genes in schizophrenia might be caused by disturbed QKI splicing.
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Affiliation(s)
- Karolina Åberg
- Departments of *Evolution, Genomics and Systematics, and
| | - Peter Saetre
- Development and Genetics, Uppsala University, SE-75236 Uppsala, Sweden; and
| | | | - Elena Jazin
- Development and Genetics, Uppsala University, SE-75236 Uppsala, Sweden; and
- To whom correspondence should be addressed. E-mail:
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42
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Ichimura K, Mungall AJ, Fiegler H, Pearson DM, Dunham I, Carter NP, Collins VP. Small regions of overlapping deletions on 6q26 in human astrocytic tumours identified using chromosome 6 tile path array-CGH. Oncogene 2006; 25:1261-71. [PMID: 16205629 PMCID: PMC2760128 DOI: 10.1038/sj.onc.1209156] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 08/25/2005] [Accepted: 09/01/2005] [Indexed: 02/02/2023]
Abstract
Deletions of chromosome 6 are a common abnormality in diverse human malignancies including astrocytic tumours, suggesting the presence of tumour suppressor genes (TSG). In order to help identify candidate TSGs, we have constructed a chromosome 6 tile path microarray. The array contains 1,780 clones (778 P1-derived artificial chromosome and 1,002 bacterial artificial chromosome) that cover 98.3% of the published chromosome 6 sequences. A total of 104 adult astrocytic tumours (10 diffuse astrocytomas, 30 anaplastic astrocytomas (AA), 64 glioblastomas (GB)) were analysed using this array. Single copy number change was successfully detected and the result was in general concordant with a microsatellite analysis. The pattern of copy number change was complex with multiple interstitial deletions/gains. However, a predominance of telomeric 6q deletions was seen. Two small common and overlapping regions of deletion at 6q26 were identified. One was 1,002 kb in size and contained PACRG and QKI, while the second was 199 kb and harbours a single gene, ARID1B. The data show that the chromosome 6 tile path array is useful in mapping copy number changes with high resolution and accuracy. We confirmed the high frequency of chromosome 6 deletions in AA and GB, and identified two novel commonly deleted regions that may harbour TSGs.
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Affiliation(s)
- K Ichimura
- Department of Pathology, Division of Molecular Histopathology, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.
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43
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Aberg K, Saetre P, Lindholm E, Ekholm B, Pettersson U, Adolfsson R, Jazin E. Human QKI, a new candidate gene for schizophrenia involved in myelination. Am J Med Genet B Neuropsychiatr Genet 2006; 141B:84-90. [PMID: 16342280 DOI: 10.1002/ajmg.b.30243] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We have previously shown that chromosome 6q25-6q27 includes a susceptibility locus for schizophrenia in a large pedigree from northern Sweden. In this study, we fine-mapped a 10.7 Mb region, included in this locus, using 42 microsatellites or SNP markers. We found a 0.5 Mb haplotype, likely to be inherited identical by decent, within the large family that is shared among the majority of the patients (69%). A gamete competition test of this haplotype in 176 unrelated nuclear families from the same geographical area as the large family showed association to schizophrenia (empirical P-value 0.041). The only gene located in the region, the quaking homolog, KH domain RNA binding (mouse) (QKI), was investigated in human brain autopsies from 55 cases and 55 controls using a high-resolution mRNA expression analysis. Relative mRNA expression levels of two QKI splice variants were clearly downregulated in schizophrenic patients (P-value 0.0004 and 0.03, respectively). The function of QKI has not been studied in humans, but the mouse homolog is involved in neural development and myelination. In conclusion, we present evidence from three unrelated sample-sets that propose the involvement of the QKI gene in schizophrenia. The two family based studies suggest that there may be functional variants of the QKI gene that increase the susceptibility of schizophrenia in northern Sweden, whereas the case-control study suggest that splicing of the gene may be disturbed in schizophrenic patients from other geographical origins. Taken together, we propose QKI as a possible target for functional studies related to the role of myelination in schizophrenia.
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Affiliation(s)
- Karolina Aberg
- Department of Evolution, Genomics and Systematics, Uppsala University, Norbyvägen 18D, 752-36 Uppsala, Sweden
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44
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Lakiza O, Frater L, Yoo Y, Villavicencio E, Walterhouse D, Goodwin EB, Iannaccone P. STAR proteins quaking-6 and GLD-1 regulate translation of the homologues GLI1 and tra-1 through a conserved RNA 3'UTR-based mechanism. Dev Biol 2005; 287:98-110. [PMID: 16198329 DOI: 10.1016/j.ydbio.2005.08.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Revised: 08/23/2005] [Accepted: 08/24/2005] [Indexed: 01/13/2023]
Abstract
The binding of the STAR protein GLD-1 to an element in the tra-2 3' untranslated region (3'UTR), called the TGE (tra GLI element), represses tra-2 translation, allowing for hermaphrodite spermatogenesis in Caenorhabditis elegans. GLD-1 is a member of the STAR family that includes the mammalian quaking (Qk) proteins. Here, we show that the 3'UTR of the nematode homologue of GLI1, called tra-1, also contains a TGE, through which translation is regulated by GLD-1. We find that GLD-1 activity is required for proper TRA-1 protein expression in hermaphrodites. RNA gel shift assays show that GLD-1 binds the predicted sites. Using reporter transgenes, we show that the human GLI1 (hGLI1) 3'UTR controls translation in the mouse embryo. We demonstrate that the addition of the mouse QK isoform-6 (QKI-6) protein to a mammalian cell line that lacks QKI-6 can confer regulation on reporter and GLI1 mRNAs in a TGE-specific manner, and reduction of QKI-6 activity with siRNA disrupts translational control. Further, siRNA knockdown of QKI-6 increases the activity of a reporter transgene that monitors the transcriptional activity of mouse Gli1 (mGli1) and increases mouse Gli1 protein. We show by immunoprecipitation that QKI-6 antibody specifically co-purifies TGE-containing mRNAs in ribonucleoproteins. Thus, we find that the mouse QKI-6 protein acts through the mGli1 and hGLI1 RNAs to repress translation. Our results suggest that STAR family-dependent translational control of GLI mRNAs is ancient, and that it existed before the division of nematodes and mammals.
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Affiliation(s)
- Olga Lakiza
- Department of Pediatrics, Northwestern University Feinberg School of Medicine and Children's Memorial Research Center, Chicago, IL 60614, USA
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45
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Murata T, Yamashiro Y, Kondo T, Nakaichi M, Une S, Taura Y. Nucleotide sequence of complementary DNA encoding for quaking protein of cow, horse and pig. DNA SEQUENCE : THE JOURNAL OF DNA SEQUENCING AND MAPPING 2005; 16:300-3. [PMID: 16147890 DOI: 10.1080/10425170500136731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Complementary DNA (cDNA) for bovine quaking gene (Bqk), equine quaking gene (Eqk) and porcine quaking gene (Pqk), which are homologous to mouse quaking gene (qkI), were isolated, and their nucleotide sequences were determined. cDNA sequences of Bqk, Eqk and Pqk showed very high homology to that of qkI at nucleotide level; 94.2, 95.7 and 95.6%, respectively. Deduced amino acid sequences for Bqk, Eqk and Pqk perfectly matched to that of qkI. These findings suggest that the quaking gene family is highly conserved during mammalian evolution, and that Bqk, Eqk and Pqk are likely to have important biological functions also in cow, horse and pig.
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Affiliation(s)
- Tomoaki Murata
- Yamaguchi University, Science Research Center, 1-1-1 Minamikogushi, Ube-city, Yamaguchi, 755-8505, Japan.
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46
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Galarneau A, Richard S. Target RNA motif and target mRNAs of the Quaking STAR protein. Nat Struct Mol Biol 2005; 12:691-8. [PMID: 16041388 DOI: 10.1038/nsmb963] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Accepted: 06/20/2005] [Indexed: 11/08/2022]
Abstract
Quaking viable (Qk(v)) mice have developmental defects that result in their characteristic tremor. The quaking (Qk) locus expresses alternatively spliced RNA-binding proteins belonging to the STAR family. To characterize the RNA binding specificity of the QKI proteins, we selected for RNA species that bound QKI from random pools of RNAs and defined the QKI response element (QRE) as a bipartite consensus sequence NACUAAY-N(1-20)-UAAY. A bioinformatic analysis using the QRE identified the three known RNA targets of QKI and 1,430 new putative mRNA targets, of which 23 were validated in vivo. A large proportion of the mRNAs are implicated in development and cell differentiation, as predicted from the phenotype of the Qk(v) mice. In addition, 24% are implicated in cell growth and/or maintenance, suggesting a role for QKI in cancer.
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Affiliation(s)
- André Galarneau
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Department of Oncology, McGill University, Montréal, Québec, Canada, H3T 1E2
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47
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Maguire ML, Guler-Gane G, Nietlispach D, Raine ARC, Zorn AM, Standart N, Broadhurst RW. Solution Structure and Backbone Dynamics of the KH-QUA2 Region of the Xenopus STAR/GSG Quaking Protein. J Mol Biol 2005; 348:265-79. [PMID: 15811367 DOI: 10.1016/j.jmb.2005.02.058] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2004] [Revised: 02/11/2005] [Accepted: 02/25/2005] [Indexed: 11/21/2022]
Abstract
The Quaking protein belongs to the family of STAR/GSG domain RNA-binding proteins and is involved in multiple cell signalling and developmental processes in vertebrates, including the formation of myelin. Heteronuclear NMR methods were used to determine the solution structure of a 134 residue fragment spanning the KH and QUA2 homology regions of the Quaking protein from Xenopus laevis (pXqua) in the absence of RNA. The protein is shown to adopt an extended type I KH domain fold that is connected to a structured alpha-helix in the C-terminal QUA2 region by means of a highly flexible linker. A comparison with the solution structure of the related protein splicing factor 1 (SF1) indicates that most aspects of the RNA-binding interface are conserved in pXqua, although the "variable loop" region that follows the second beta-strand possesses two additional alpha-helices. The structure of pXqua provides an appropriate template for building models of important homologues, such as GLD-1 and Sam68. Measurements of the (15)N relaxation parameters of pXqua confirm that the polypeptide backbone of the QUA2 region is more dynamic than that of the KH portion, and that the C-terminal helix is partially structured in the absence of RNA. By comparison with a random coil reference state, the nascent structure in the QUA2 region is estimated to contribute 15.5kJmol(-1) to the change in conformational free energy that occurs on forming a complex with RNA. Since STAR/GSG proteins may regulate alternative splicing by competing with SF1 in the nucleus for specific branch-point sequences that signal intronic RNA, the formation of secondary structure in the QUA2 region in the unbound state of pXqua has important functional consequences.
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Affiliation(s)
- Mahon L Maguire
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
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48
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Zhou GJ, Zhang Y, Wang J, Guo JH, Ni J, Zhong ZM, Wang LQ, Dang YJ, Dai JF, Yu L. Cloning and characterization of a novel human RNA binding protein gene PNO1. ACTA ACUST UNITED AC 2005; 15:219-24. [PMID: 15497447 DOI: 10.1080/10425170410001702159] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Present work reported the cloning and characterization of a human novel RNA binding gene Partner of NOB1 (PNO1), with a length of 1637bp and a putative open reading frame of 759 bp, isolated from human kidney. It is composed of seven exons and is localized on chromosome 2p14. Western blot showed that the molecular weight of PNO1 is about 35kDa. RT-PCR results in 16 human tissues indicated that PNO1 is expressed mainly in liver, lung, spleen and kidney, slightly in thymus, testis, ovary, respectively, but not in heart, brain, skeletal muscle, placenta, pancreas, prostate, small intestine, colon and peripheral blood leukocytes. GFP fusion expression in mammalian cells exhibited its localization in the nucleus, especially in nucleoli. Subcellular localization of thirteen GFP fusion PNO1 deletion proteins showed that the region of 92-230 aa is solely responsible for its nucleolar retention, and KH domain alone is not sufficient for nucleolar retention. The PNO1 family shows significant conservation in both eukaryotes and prokaryotes.
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Affiliation(s)
- Guang-Jin Zhou
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 220 Handan Road, Shanghai 200433, P.R. China
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49
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Zhang Y, Lu Z, Ku L, Chen Y, Wang H, Feng Y. Tyrosine phosphorylation of QKI mediates developmental signals to regulate mRNA metabolism. EMBO J 2003; 22:1801-10. [PMID: 12682013 PMCID: PMC154463 DOI: 10.1093/emboj/cdg171] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The selective RNA-binding protein QKI is essential for myelination in the central nervous system (CNS). QKI belongs to the family of signal transduction activators of RNA (STARs), characteristic of binding RNA and signaling molecules, therefore is postulated to regulate RNA homeostasis in response to developmental signals. Here we report that QKI acts downstream of the Src family protein tyrosine kinases (Src-PTKs) during CNS myelination. QKI selectively interacted with the mRNA encoding the myelin basic protein (MBP). Such interaction stabilized MBP mRNA and was required for the rapid accumulation of MBP mRNA during active myelinogenesis. We found that the interaction between QKI and MBP mRNA was negatively regulated by Src-PTK-dependent phosphorylation of QKI. During early myelin development, tyrosine phosphorylation of QKI in the developing myelin drastically declined, presumably leading to enhanced interactions between QKI and MBP mRNA, which was associated with the rapid accumulation of MBP mRNA and accelerated myelin production. Therefore, developmental regulation of Src-PTK-dependent tyrosine phosphorylation of QKI suggests a novel mechanism for accelerating CNS myelinogenesis via regulating mRNA metabolism.
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Affiliation(s)
- Youyi Zhang
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
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