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Yu S, Chen C, Chen M, Liang J, Jiang K, Lou B, Lu J, Zhu X, Zhou D. MAGOH promotes gastric cancer progression via hnRNPA1 expression inhibition-mediated RONΔ160/PI3K/AKT signaling pathway activation. J Exp Clin Cancer Res 2024; 43:32. [PMID: 38268030 PMCID: PMC10809607 DOI: 10.1186/s13046-024-02946-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/05/2024] [Indexed: 01/26/2024] Open
Abstract
BACKGROUND Gastric cancer (GC) is associated with high mortality and heterogeneity and poses a great threat to humans. Gene therapies for the receptor tyrosine kinase RON and its spliceosomes are attracting increasing amounts of attention due to their unique characteristics. However, little is known about the mechanism involved in the formation of the RON mRNA alternative spliceosome RONΔ160. METHODS Fourteen human GC tissue samples and six normal gastric tissue samples were subjected to label-free relative quantitative proteomics analysis, and MAGOH was identified as a candidate protein for subsequent studies. The expression of MAGOH in clinical specimens was verified by quantitative real-time PCR and western blotting. We then determined the biological function of MAGOH in GC through in vitro and in vivo experiments. RNA pulldown, RNA sequencing and RNA immunoprecipitation (RIP) were subsequently conducted to uncover the underlying mechanism by which MAGOH regulated the formation of RONΔ160. RESULTS Proteomic analysis revealed that MAGOH, which is located at key nodes and participates in RNA processing and mRNA splicing, was upregulated in GC tissue and GC cell lines and was associated with poor prognosis. Functional analysis showed that MAGOH promoted the proliferation, migration and invasion of GC cells in vitro and in vivo. Mechanistically, MAGOH inhibited the expression of hnRNPA1 and reduced the binding of hnRNPA1 to RON mRNA, thereby promoting the formation of RONΔ160 to activate the PI3K/AKT signaling pathway and consequently facilitating GC progression. CONCLUSIONS Our study revealed that MAGOH could promote the formation of RONΔ160 and activate the PI3K/AKT signaling pathway through the inhibition of hnRNPA1 expression. We elucidate a novel mechanism and potential therapeutic targets for the growth and metastasis of GC based on the MAGOH-RONΔ160 axis, and these findings have important guiding significance and clinical value for the future development of effective therapeutic strategies for GC.
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Affiliation(s)
- Shanshan Yu
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Cheng Chen
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ming Chen
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jinxiao Liang
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Kecheng Jiang
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Bin Lou
- Department of Laboratory Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jun Lu
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaohua Zhu
- Department of Oncology, Shaoxing People's Hospital, Shaoxing, China
| | - Donghui Zhou
- Department of Surgical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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Lopez-Pedrera C, Patiño-Trives AM, Cerdó T, Ortega-Castro R, Sanchez-Pareja I, Ibañez-Costa A, Muñoz-Barrera L, Ábalos-Aguilera MC, Ruiz-Vilchez D, Seguí Azpilcueta P, Espinosa M, Barbarroja N, Escudero-Contreras A, Castaño JP, Luque RM, Ortega R, Aguirre MA, Perez-Sanchez C. Splicing machinery is profoundly altered in systemic lupus erythematosus and antiphospholipid syndrome and directly linked to key clinical features. J Autoimmun 2023; 135:102990. [PMID: 36621176 DOI: 10.1016/j.jaut.2022.102990] [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: 09/13/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 01/09/2023]
Abstract
OBJECTIVES To characterize the splicing machinery (SM) of leukocytes from primary antiphospholipid syndrome (APS), systemic lupus erythematosus (SLE) and antiphospholipid syndrome with lupus (APS + SLE) patients, and to assess its clinical involvement. METHODS Monocytes, lymphocytes and neutrophils from 80 patients (22 APS, 35 SLE and 23 APS + SLE) and 50 HD were purified, and 45 selected SM components were evaluated by qPCR-microfluidic array. Relationship with clinical features and underlying regulatory mechanisms were assessed. RESULTS APS, SLE and APS + SLE leukocytes displayed significant and specific alterations in SM-components (SMC), associated with clinical features [autoimmune profiles, disease activity, lupus nephritis (LN), and CV-risk markers]. A remarkable relationship among dysregulated SMC in monocytes and the presence of LN in SLE was highlighted, revealing a novel pathological mechanism, which was further explored. Immunohistology analysis of renal biopsies highlighted the pathological role of the myeloid compartment in LN. Transcriptomic analysis of monocytes from SLE-LN(+) vs SLE-LN(-) identified 271 genes differentially expressed, mainly involved in inflammation and IFN-signaling. Levels of IFN-related genes correlated with those of SMC in SLE-LN(+). These results were validated in two external SLE-LN(+) datasets of whole-blood and kidney biopsies. In vitro, SLE-LN(+)-serum promoted a concomitant dysregulation of both, the IFN signature and several SMC, further reversed by JAKinibs treatment. Interestingly, IFNs, key inflammatory cytokines in SLE pathology, also altered SMC. Lastly, the over/down-expression of selected SMC in SLE-monocytes reduced the release of inflammatory cytokines and their adhesion capacity. CONCLUSION Overall, we have identified, for the first time, a specific alteration of SMC in leukocytes from APS, SLE and APS + SLE patients that would be responsible for the development of distinctive clinical profiles.
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Affiliation(s)
- Ch Lopez-Pedrera
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain.
| | - A M Patiño-Trives
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - T Cerdó
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - R Ortega-Castro
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - I Sanchez-Pareja
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - A Ibañez-Costa
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), 14004, Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, 14004, Córdoba, Spain; Reina Sofia University Hospital, 14004, Córdoba, Spain; CIBER Fisiopatología de La Obesidad y Nutrición (CIBERobn), 14004, Córdoba, Spain
| | - L Muñoz-Barrera
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - M C Ábalos-Aguilera
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - D Ruiz-Vilchez
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - P Seguí Azpilcueta
- Radiology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - M Espinosa
- Nephrology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - N Barbarroja
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - A Escudero-Contreras
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - J P Castaño
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), 14004, Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, 14004, Córdoba, Spain; Reina Sofia University Hospital, 14004, Córdoba, Spain; CIBER Fisiopatología de La Obesidad y Nutrición (CIBERobn), 14004, Córdoba, Spain
| | - R M Luque
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), 14004, Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, 14004, Córdoba, Spain; Reina Sofia University Hospital, 14004, Córdoba, Spain; CIBER Fisiopatología de La Obesidad y Nutrición (CIBERobn), 14004, Córdoba, Spain
| | - R Ortega
- Pathology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - M A Aguirre
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
| | - C Perez-Sanchez
- Rheumatology Service, Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004, Córdoba, Spain
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Mitra R, Rehman A, Singh KK, Jaganathan BG. Multifaceted roles of MAGOH Proteins. Mol Biol Rep 2023; 50:1931-1941. [PMID: 36396768 DOI: 10.1007/s11033-022-07904-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 07/14/2022] [Accepted: 08/31/2022] [Indexed: 11/18/2022]
Abstract
MAGOH and MAGOHB are paralog proteins that can substitute each other in the exon junction complex (EJC). The EJC is formed of core components EIF4A3, RBM8A, and MAGOH/MAGOHB. As a part of the EJC, MAGOH proteins are required for mRNA splicing, export, translation and nonsense-mediated mRNA decay (NMD). MAGOH is also essential for embryonic development and normal cellular functioning. The haploinsufficiency of MAGOH results in disorders such as microcephaly and cancer. The present review discusses the discovery of MAGOH, its paralog MAGOHB, their roles in cellular function as part of the EJC, and other cellular roles that are not directly associated with mRNA processing. We also discuss how MAGOH haploinsufficiency in cancer cells can be exploited to develop a novel targeted cancer treatment.
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Affiliation(s)
- Rumela Mitra
- Stem Cells and Cancer Biology Research Group, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam, India
| | - Ayushi Rehman
- RNA-Binding Proteins (RBPs) Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam, India
| | - Kusum Kumari Singh
- RNA-Binding Proteins (RBPs) Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam, India.
| | - Bithiah Grace Jaganathan
- Stem Cells and Cancer Biology Research Group, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam, India.
- Jyoti and Bhupat Mehta School of Health Sciences and Technology, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam, India.
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Martin H, Rupkey J, Asthana S, Yoon J, Patel S, Mott J, Pei Z, Mao Y. Diverse Roles of the Exon Junction Complex Factors in the Cell Cycle, Cancer, and Neurodevelopmental Disorders-Potential for Therapeutic Targeting. Int J Mol Sci 2022; 23:ijms231810375. [PMID: 36142288 PMCID: PMC9499366 DOI: 10.3390/ijms231810375] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/01/2022] [Accepted: 09/05/2022] [Indexed: 12/04/2022] Open
Abstract
The exon junction complex (EJC) plays a crucial role in regulating gene expression at the levels of alternative splicing, translation, mRNA localization, and nonsense-mediated decay (NMD). The EJC is comprised of three core proteins: RNA-binding motif 8A (RBM8A), Mago homolog (MAGOH), eukaryotic initiation factor 4A3 (eIF4A3), and a peripheral EJC factor, metastatic lymph node 51 (MLN51), in addition to other peripheral factors whose structural integration is activity-dependent. The physiological and mechanistic roles of the EJC in contribution to molecular, cellular, and organismal level function continue to be explored for potential insights into genetic or pathological dysfunction. The EJC’s specific role in the cell cycle and its implications in cancer and neurodevelopmental disorders prompt enhanced investigation of the EJC as a potential target for these diseases. In this review, we highlight the current understanding of the EJC’s position in the cell cycle, its relation to cancer and developmental diseases, and potential avenues for therapeutic targeting.
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Affiliation(s)
- Hannah Martin
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Julian Rupkey
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Shravan Asthana
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
- Feinberg School of Medicine, Northwestern University, 303 East Superior Street, Chicago, IL 60611, USA
| | - Joy Yoon
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Shray Patel
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Jennifer Mott
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Zifei Pei
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
| | - Yingwei Mao
- Department of Biology, Pennsylvania State University, University Park, State College, PA 16802, USA
- Correspondence:
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The Physiological Roles of the Exon Junction Complex in Development and Diseases. Cells 2022; 11:cells11071192. [PMID: 35406756 PMCID: PMC8997533 DOI: 10.3390/cells11071192] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/19/2022] [Accepted: 03/24/2022] [Indexed: 01/12/2023] Open
Abstract
The exon junction complex (EJC) becomes an increasingly important regulator of early gene expression in the central nervous system (CNS) and other tissues. The EJC is comprised of three core proteins: RNA-binding motif 8A (RBM8A), Mago homolog (MAGOH), eukaryotic initiation factor 4A3 (EIF4A3), and a peripheral EJC factor, metastatic lymph node 51 (MLN51), together with various auxiliary factors. The EJC is assembled specifically at exon-exon junctions on mRNAs, hence the name of the complex. The EJC regulates multiple levels of gene expression, from splicing to translation and mRNA degradation. The functional roles of the EJC have been established as crucial to the normal progress of embryonic and neurological development, with wide ranging implications on molecular, cellular, and organism level function. Dysfunction of the EJC has been implicated in multiple developmental and neurological diseases. In this review, we discuss recent progress on the EJC’s physiological roles.
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Lin Y, Wei L, Hu B, Zhang J, Wei J, Qian Z, Zou D. RBM8A Promotes Glioblastoma Growth and Invasion Through the Notch/STAT3 Pathway. Front Oncol 2021; 11:736941. [PMID: 34804926 PMCID: PMC8600138 DOI: 10.3389/fonc.2021.736941] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/19/2021] [Indexed: 12/15/2022] Open
Abstract
Background Glioblastoma (GBM) is a prevalent brain malignancy with an extremely poor prognosis, which is attributable to its invasive biological behavior. The RNA-binding motif protein 8A (RBM8A) has different effects on various human cancers. However, the role of RBM8A in GBM progression remains unclear. Methods We investigated the expression levels of RBM8A in 94 GBM patients and explored the correlation between RBM8A expression and patient prognosis. Using in vitro and in vivo assays, combined with GBM sequencing data from the Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA), we examined whether and how RBM8A contributes to GBM progression. Results RBM8A was up-regulated in GBM tissues, and its higher expression correlated with worse prognosis. Knockdown of RBM8A inhibited GBM progression and invasion ability both in vitro and in vivo. On the contrary, overexpression of RBM8A promoted GBM progression and invasion ability. Enrichment analysis of differentially expressed genes in GBM data identified the Notch1/STAT3 network as a potential downstream target of RBM8A, and this was supported by molecular docking studies. Furthermore, we demonstrated that RBM8A regulates the transcriptional activity of CBF1. The γ-secretase inhibitor DAPT significantly reversed RBM8A-enhanced GBM cell proliferation and invasion, and was associated with down-regulation of p-STAT3 and Notch1 protein. Finally, the gene set variance analysis score of genes involved in regulation of the Notch1/STAT3 network by RBM8A showed good diagnostic and prognostic value for GBM. Conclusions RBM8A may promote GBM cell proliferation and migration by activating the Notch/STAT3 pathway in GBM cells, suggesting that RBM8A may serve as a potential therapeutic target for the treatment of GBM.
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Affiliation(s)
- Yan Lin
- Department of Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Lei Wei
- Department of Neurology, The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Beiquan Hu
- Department of Neurosurgery, The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Jinyan Zhang
- Department of Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Jiazhang Wei
- Department of Otolaryngology & Head and Neck, The People's Hospital of Guangxi Zhuang Autonomous Region, Guangxi Academy of Medical Sciences, Nanning, China
| | - Zhongrun Qian
- Department of Neurosurgery, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, Hefei, China
| | - Donghua Zou
- Department of Neurology, The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, China
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A Comprehensive Pan-Cancer Analysis of RBM8A Based on Data Mining. JOURNAL OF ONCOLOGY 2021; 2021:9983354. [PMID: 34326876 PMCID: PMC8277506 DOI: 10.1155/2021/9983354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/02/2021] [Indexed: 01/01/2023]
Abstract
Background As a member of the exon junction complex (EJC), RNA-binding motif protein 8A (RBM8A) plays a crucial role in the maintenance of mRNA and multiple activities of an organism. Immunotherapy has been proven to be a staple type of cancer treatment. However, the role of RBM8A and immunity across cancer types is unclear. Objective This study aims to visualize the expression, prognosis, mutations, and coexpressed gene results of RBM8A across cancer types and to explore the link between RBM8A expression and immunity. Methods In this study, data were collected from multiple online databases. We analyzed the data using the HPA, UALCAN Database, COSMIC, cBioPortal, Cancer Regulome tools, Kaplan–Meier Plotter, and TIMER website. Results For the expression of RBM8A in normal tissues, higher expression of RBM8A was observed in immune-related cells than in nonimmune organs. The expression level of RBM8A was related to tumor type. Missense mutations in RBM8A were found in most tumors and affected the prognosis of carcinomas with coexpressed genes. RBM8A was strongly associated with immune-infiltrating cells and immune checkpoint inhibitors, especially in LIHC. Conclusions RBM8A is a gene worth exploring and may be a unique immune target in the future.
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Lin Y, Liang R, Qiu Y, Lv Y, Zhang J, Qin G, Yuan C, Liu Z, Li Y, Zou D, Mao Y. Expression and gene regulation network of RBM8A in hepatocellular carcinoma based on data mining. Aging (Albany NY) 2020; 11:423-447. [PMID: 30670676 PMCID: PMC6366983 DOI: 10.18632/aging.101749] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/25/2018] [Indexed: 12/11/2022]
Abstract
RNA binding motif protein 8A (RBM8A) is an RNA binding protein in a core component of the exon junction complex. Abnormal RBM8A expression is associated with carcinogenesis. We used sequencing data from the Cancer Genome Atlas database and Gene Expression Omnibus, analyzed RBM8A expression and gene regulation networks in hepatocellular carcinoma (HCC). Expression was analyzed using OncomineTM and Gene Expression Profiling Interactive Analysis tools, while RBM8A alterations and related functional networks were identified using cBioPortal. LinkedOmics was used to identify differential gene expression with RBM8A and to analyze Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways. Gene enrichment analysis examined target networks of kinases, miRNAs and transcription factors. We found that RBM8A is overexpressed and the RBM8A gene often amplified in HCC. Expression of this gene is linked to functional networks involving the ribosome and RNA metabolic signaling pathways. Functional network analysis suggested that RBM8A regulates the spliceosome, ribosome, DNA replication and cell cycle signaling via pathways involving several cancer-related kinases, miRNAs and E2F Transcription Factor 1. Our results demonstrate that data mining efficiently reveals information about RBM8A expression and potential regulatory networks in HCC, laying a foundation for further study of the role of RBM8A in carcinogenesis.
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Affiliation(s)
- Yan Lin
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Rong Liang
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Yufen Qiu
- Maternal and Child Health Hospital and Obstetrics and Gynecology Hospital of Guangxi Zhuang Autonomous Region, Guangxi 530021, People's Republic of China
| | - Yufeng Lv
- Department of Medical Oncology, Affiliated Langdong Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Jinyan Zhang
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Gang Qin
- The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Chunling Yuan
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Zhihui Liu
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Yongqiang Li
- Department of Medical Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Donghua Zou
- The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, People's Republic of China
| | - Yingwei Mao
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
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Rahman MA, Lin KT, Bradley RK, Abdel-Wahab O, Krainer AR. Recurrent SRSF2 mutations in MDS affect both splicing and NMD. Genes Dev 2020; 34:413-427. [PMID: 32001512 PMCID: PMC7050488 DOI: 10.1101/gad.332270.119] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 12/20/2019] [Indexed: 12/23/2022]
Abstract
Oncogenic mutations in the RNA splicing factors SRSF2, SF3B1, and U2AF1 are the most frequent class of mutations in myelodysplastic syndromes and are also common in clonal hematopoiesis, acute myeloid leukemia, chronic lymphocytic leukemia, and a variety of solid tumors. They cause genome-wide splicing alterations that affect important regulators of hematopoiesis. Several mRNA isoforms promoted by the various splicing factor mutants comprise a premature termination codon (PTC) and are therefore potential targets of nonsense-mediated mRNA decay (NMD). In light of the mechanistic relationship between splicing and NMD, we sought evidence for a specific role of mutant SRSF2 in NMD. We show that SRSF2 Pro95 hot spot mutations elicit enhanced mRNA decay, which is dependent on sequence-specific RNA binding and splicing. SRSF2 mutants enhance the deposition of exon junction complexes (EJCs) downstream from the PTC through RNA-mediated molecular interactions. This architecture then favors the association of key NMD factors to elicit mRNA decay. Gene-specific blocking of EJC deposition by antisense oligonucleotides circumvents aberrant NMD promoted by mutant SRSF2, restoring the expression of PTC-containing transcript. Our study uncovered critical effects of SRSF2 mutants in hematologic malignancies, reflecting the regulation at multiple levels of RNA metabolism, from splicing to decay.
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Affiliation(s)
| | - Kuan-Ting Lin
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | - Robert K Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Omar Abdel-Wahab
- Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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Ma Q, Tatsuno T, Nakamura Y, Ishigaki Y. The stability of Magoh and Y14 depends on their heterodimer formation and nuclear localization. Biochem Biophys Res Commun 2019; 511:631-636. [PMID: 30826064 DOI: 10.1016/j.bbrc.2019.02.097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 02/19/2019] [Indexed: 01/10/2023]
Abstract
Reduced expression of the Y14 gene is a cause of Thrombocytopenia-absent radius (TAR) syndrome. This gene contains a conserved RNA recognition motif (RRM) in the central region and nuclear localization/export sequences (NLS/NES) in the N-terminal. Y14 and Magoh proteins form tight heterodimers and are the core of exon junction complexes (EJCs), which mediate various processes of mRNA metabolism after transcription. In this report, we found that protein expression levels of exogenously expressed Magoh L136R and Y14 L118R (leucine-to-arginine substitution at amino acid residue 136 and 118 respectively, that results in the formation of the complex being lost) are lower than their wild-types. This reduction is likely caused by protein levels, as no difference in mRNA levels was detected. Meanwhile, a cycloheximide chase assay determined that the degradation rates of Magoh L136R and Y14 L118R were faster than their wild-types. Both Y14 L118R and Magoh L136R lost the ability to form heterodimers with corresponding wild-type proteins. However, Y14 L118R is able to still localize in the nucleus which causes the stability of Y14 L118R to be higher than Magoh L136R. These results reveal that the stability of Magoh and Y14 is not only dependent on the heterodimer structure, but also dependent on nuclear localization.
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Affiliation(s)
- Qingfeng Ma
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Japan; Department of Clinical Laboratory, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Takanori Tatsuno
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Japan
| | - Yuka Nakamura
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Japan
| | - Yasuhito Ishigaki
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Japan.
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C-terminal short arginine/serine repeat sequence-dependent regulation of Y14 (RBM8A) localization. Sci Rep 2018; 8:612. [PMID: 29330450 PMCID: PMC5766523 DOI: 10.1038/s41598-017-18765-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/15/2017] [Indexed: 01/01/2023] Open
Abstract
Y14 (RBM8A) is an RNA recognition motif-containing protein that forms heterodimers with MAGOH and serves as a core factor of the RNA surveillance machinery for the exon junction complex (EJC). The role of the Y14 C-terminal serine/arginine (RS) repeat-containing region, which has been reported to undergo modifications such as phosphorylation and methylation, has not been sufficiently investigated. Thus, we aimed to explore the functional significance of the Y14 C-terminal region. Deletion or dephosphorylation mimic mutants of the C-terminal region showed a shift in localization from the nucleoplasmic region; in addition, the C-terminal RS repeat-containing sequence itself exhibited the potential for nucleolar localization. Additionally, the regulation of Y14 localization by the C-terminal region was further found to be exquisitely controlled by MAGOH binding. Cumulatively, our findings, which demonstrated that Y14 localization is regulated not only by the previously reported N-terminal localization signal but also by the C-terminal RS repeat-containing region through phosphorylation and MAGOH binding to Y14, provide new insights for the mechanism of localization of short RS repeat-containing proteins.
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12
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Manukjan G, Bösing H, Schmugge M, Strauß G, Schulze H. Impact of genetic variants on haematopoiesis in patients with thrombocytopenia absent radii (TAR) syndrome. Br J Haematol 2017; 179:606-617. [DOI: 10.1111/bjh.14913] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 07/23/2017] [Indexed: 01/31/2023]
Affiliation(s)
- Georgi Manukjan
- Institute of Experimental Biomedicine, Chair I; University Hospital Würzburg; Würzburg Germany
| | - Hendrik Bösing
- Institute of Experimental Biomedicine, Chair I; University Hospital Würzburg; Würzburg Germany
- Laboratory of Paediatric Molecular Biology; Charité - University Hospital Berlin; Berlin Germany
| | | | - Gabriele Strauß
- Department of Paediatric Haematology and Oncology; Helios-Klinikum Buch; Berlin Germany
| | - Harald Schulze
- Institute of Experimental Biomedicine, Chair I; University Hospital Würzburg; Würzburg Germany
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13
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Togi S, Muromoto R, Hirashima K, Kitai Y, Okayama T, Ikeda O, Matsumoto N, Kon S, Sekine Y, Oritani K, Matsuda T. A New STAT3-binding Partner, ARL3, Enhances the Phosphorylation and Nuclear Accumulation of STAT3. J Biol Chem 2016; 291:11161-71. [PMID: 27048653 DOI: 10.1074/jbc.m116.724849] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Indexed: 01/05/2023] Open
Abstract
Signal transducer and activator of transcription 3 (STAT3) is involved in cell proliferation, differentiation, and cell survival during immune responses, hematopoiesis, neurogenesis, and other biological processes. STAT3 activity is regulated by a variety of mechanisms, including phosphorylation and nuclear translocation. To clarify the molecular mechanisms underlying the regulation of STAT3 activity, we performed yeast two-hybrid screening. We identified ARL3 (ADP-ribosylation factor-like 3) as a novel STAT3-binding partner. ARL3 recognizes the DNA-binding domain as well as the C-terminal region of STAT3 in vivo, and their binding was the strongest when both proteins were activated. Importantly, small interfering RNA-mediated reduction of endogenous ARL3 expression decreased IL-6-induced tyrosine phosphorylation, nuclear accumulation, and transcriptional activity of STAT3. These results indicate that ARL3 interacts with STAT3 and regulates the transcriptional activation of STAT3 by influencing its nuclear accumulation of STAT3.
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Affiliation(s)
- Sumihito Togi
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Ryuta Muromoto
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Koki Hirashima
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Yuichi Kitai
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Taichiro Okayama
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Osamu Ikeda
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Naoki Matsumoto
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Shigeyuki Kon
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Yuichi Sekine
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
| | - Kenji Oritani
- the Department of Hematology and Oncology, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Tadashi Matsuda
- From the Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12 Nishi-6, Kita-Ku, Sapporo, 060-0812 and
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14
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Matsuda T, Muromoto R, Sekine Y, Togi S, Kitai Y, Kon S, Oritani K. Signal transducer and activator of transcription 3 regulation by novel binding partners. World J Biol Chem 2015; 6:324-332. [PMID: 26629315 PMCID: PMC4657126 DOI: 10.4331/wjbc.v6.i4.324] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 05/02/2015] [Accepted: 09/02/2015] [Indexed: 02/05/2023] Open
Abstract
Signal transducers and activators of transcription (STATs) mediate essential signals for various biological processes, including immune responses, hematopoiesis, and neurogenesis. STAT3, for example, is involved in the pathogenesis of various human diseases, including cancers, autoimmune and inflammatory disorders. STAT3 activation is therefore tightly regulated at multiple levels to prevent these pathological conditions. A number of proteins have been reported to associate with STAT3 and regulate its activity. These STAT3-interacting proteins function to modulate STAT3-mediated signaling at various steps and mediate the crosstalk of STAT3 with other cellular signaling pathways. This article reviews the roles of novel STAT3 binding partners such as DAXX, zipper-interacting protein kinase, Krüppel-associated box-associated protein 1, Y14, PDZ and LIM domain 2 and signal transducing adaptor protein-2, in the regulation of STAT3-mediated signaling.
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15
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Abstract
The cerebral cortex is built during embryonic neurogenesis, a period when excitatory neurons are generated from progenitors. Defects in neurogenesis can cause acute neurodevelopmental disorders, such as microcephaly (reduced brain size). Altered dosage of the 1q21.1 locus has been implicated in the etiology of neurodevelopmental phenotypes; however, the role of 1q21.1 genes in neurogenesis has remained elusive. Here, we show that haploinsufficiency for Rbm8a, an exon junction complex (EJC) component within 1q21.1, causes severe microcephaly and defective neurogenesis in the mouse. At the onset of neurogenesis, Rbm8a regulates radial glia proliferation and prevents premature neuronal differentiation. Reduced Rbm8a levels result in subsequent apoptosis of neurons, and to a lesser extent, radial glia. Hence, compared to control, Rbm8a-haploinsufficient brains have fewer progenitors and neurons, resulting in defective cortical lamination. To determine whether reciprocal dosage change of Rbm8a alters embryonic neurogenesis, we overexpressed human RBM8A in two animal models. Using in utero electroporation of mouse neocortices as well as zebrafish models, we find RBM8A overexpression does not significantly perturb progenitor number or head size. Our findings demonstrate that Rbm8a is an essential neurogenesis regulator, and add to a growing literature highlighting roles for EJC components in cortical development and neurodevelopmental pathology. Our results indicate that disruption of RBM8A may contribute to neurodevelopmental phenotypes associated with proximal 1q21.1 microdeletions.
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16
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Ishigaki Y, Nakamura Y, Tatsuno T, Ma S, Tomosugi N. Phosphorylation status of human RNA-binding protein 8A in cells and its inhibitory regulation by Magoh. Exp Biol Med (Maywood) 2014; 240:438-45. [PMID: 25349214 DOI: 10.1177/1535370214556945] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 09/11/2014] [Indexed: 11/17/2022] Open
Abstract
The RNA-binding protein 8A (RBM8A)-mago-nashi homolog, proliferation-associated (Magoh) complex is a component of the exon junction complex (EJC) required for mRNA metabolism involving nonsense-mediated mRNA decay (NMD). RBM8A is a phosphorylated protein that plays some roles in NMD. However, the detailed status and mechanism of the phosphorylation of RBM8A is not completely understood. Therefore, in this study, we analyzed in detail RBM8A phosphorylation in human cells. Accordingly, analysis of the phosphorylation status of RBM8A protein in whole-cell lysates by using Phos-tag gels revealed that the majority of endogenous RBM8A was phosphorylated throughout the cell-cycle progression. Nuclear and cytoplasmic RBM8A and RBM8A in the EJC were also found to be mostly phosphorylated. We also screened the phosphorylated serine by mutational analysis using Phos-tag gels to reveal modifications of serine residues 166 and 168. A single substitution at position 168 that concomitantly abolished the phosphorylation of serine 166 suggested the priority of kinase reaction between these sites. Furthermore, analysis of the role of the binding protein Magoh in RBM8A phosphorylation revealed its inhibitory effect in vitro and in vivo. Thus, we conclude that almost all synthesized RBM8A proteins are rapidly phosphorylated in cells and that phosphorylation occurs before the complex formation with Magoh.
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Affiliation(s)
- Yasuhito Ishigaki
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Ishikawa 920-0293, Japan
| | - Yuka Nakamura
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Ishikawa 920-0293, Japan
| | - Takanori Tatsuno
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Ishikawa 920-0293, Japan
| | - Shaofu Ma
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Ishikawa 920-0293, Japan
| | - Naohisa Tomosugi
- Medical Research Institute, Kanazawa Medical University, Uchinada, Kahoku, Ishikawa 920-0293, Japan Medical Care Proteomics Biotechnology Co., Ltd., Uchinada-machi, Kahoku 920-0293, Japan
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17
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Ishigaki Y, Nakamura Y, Tatsuno T, Hashimoto M, Shimasaki T, Iwabuchi K, Tomosugi N. Depletion of RNA-binding protein RBM8A (Y14) causes cell cycle deficiency and apoptosis in human cells. Exp Biol Med (Maywood) 2014; 238:889-97. [PMID: 23970407 DOI: 10.1177/1535370213494646] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RBM8A (Y14) contains an RNA-binding motif and forms a tight heterodimer with Magoh. The heterodimer is known to be a member of the exon junction complex that forms on mRNA before export and it is required for mRNA metabolism processes such as splicing, mRNA export and nonsense-mediated mRNA decay. Recently, deficient cellular proliferation has been observed in RBM8A- or Magoh-depleted cells. These results prompted us to study the role of RBM8A in cell cycle progression of human tumour cells. The depletion of RBM8A in A549 cells resulted in poor cell survival and the accumulation of mitotic cells. After release from G1/S arrest induced by a double thymidine block, the RBM8A-silenced cells could not proceed to the next G1 phase beyond G2/M phase. Finally, the sub-G1 population increased and the apoptosis markers caspases 3/7 were activated. Silenced cells exhibited an increased frequency of multipolar or monopolar centrosomes, which may have caused the observed deficiency in cell cycle progression. Finally, silencing of either RBM8A or Magoh resulted in mutual downregulation of the other protein. These results illustrate that the RBM8A-Magoh mRNA binding complex is required for M phase progression and both proteins may be novel targets for anticancer therapy.
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Affiliation(s)
- Yasuhito Ishigaki
- Division of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Uchinada-machi, Kahoku-gun 920-0293, Japan
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18
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Ishigaki Y, Nakamura Y, Tatsuno T, Hashimoto M, Iwabuchi K, Tomosugi N. RNA-binding protein RBM8A (Y14) and MAGOH localize to centrosome in human A549 cells. Histochem Cell Biol 2013; 141:101-9. [PMID: 23949737 DOI: 10.1007/s00418-013-1135-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2013] [Indexed: 10/26/2022]
Abstract
RBM8A (Y14) is carrying RNA-binding motif and forms the tight heterodimer with MAGOH. The heterodimer is known to be a member of exon junction complex on exporting mRNA and is required for mRNA metabolisms such as splicing, mRNA export and nonsense-mediated mRNA decay. Almost all RBM8A-MAGOH complexes localize in nucleoplasm and shuttle between nuclei and cytoplasm for RNA metabolism. Recently, the abnormality of G2/M transition and aberrant centrosome regulation in RBM8A- or MAGOH-deficient cells has been reported. These results prompt us to the reevaluation of the localization of RBM8A-MAGOH in human cells. Interestingly, our immunostaining experiments showed the localization of these proteins in centrosome in addition to nuclei. Furthermore, the transiently expressed eYFP-tagged RBM8A and Flag-tagged MAGOH also co-localized with centrosome signals. In addition, the proximity ligation in situ assay was performed to detect the complex formation in centrosome. Our experiments clearly showed that Myc-tagged RBM8A and Flag-tagged MAGOH formed a complex in centrosome. GFP-tagged PLK1 also co-localized with Myc-RBM8A. Our results show that RBM8A-MAGOH complex is required for M-phase progression via direct localization to centrosome rather than indirect effect.
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Affiliation(s)
- Yasuhito Ishigaki
- Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku, 920-0293, Japan,
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19
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Togi S, Shiga K, Muromoto R, Kato M, Souma Y, Sekine Y, Kon S, Oritani K, Matsuda T. Y14 positively regulates TNF-α-induced NF-κB transcriptional activity via interacting RIP1 and TRADD beyond an exon junction complex protein. THE JOURNAL OF IMMUNOLOGY 2013; 191:1436-44. [PMID: 23817415 DOI: 10.4049/jimmunol.1300501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Although Y14 is known to be a component of the exon junction complex, we previously reported that Y14 regulates IL-6-induced STAT3 activation. In this study, we showed that endogenous Y14 positively regulated TNF-α-induced IL-6 expression in HeLa cells. Small interfering RNA-mediated Y14-knockdown reduced TNF-α-induced and NF-κB-mediated transcriptional activity, phosphorylation/degradation of IκBα, and nuclear localization of NF-κB/p65. As in the case of IL-6 stimuli, Y14 enhanced TNF-α-induced STAT3 phosphorylation, which is important for its nuclear retention. However, our manipulation of Y14 expression indicated that it is involved in TNF-α-induced IL-6 expression via both STAT3-dependent and -independent mechanisms. We screened signaling molecules in the TNF-α-NF-κB pathway and found that Y14 endogenously associated with receptor-interacting protein 1 (RIP1) and TNFR-associated death domain (TRADD). Overexpression of RIP1, but not TRADD, restored TNF-α-induced NF-κB activation in Y14-knockdown cells, and Y14 overexpression restored TNF-α-induced NF-κB activation in TRADD-knockdown cells, but not in RIP1-knockdown cells, indicating that Y14 lies downstream of TRADD and upstream of RIP1. Of importance, Y14 significantly enhanced the binding between RIP1 and TRADD, and this is a possible new mechanism for Y14-mediated modification of TNF-α signals. Although Y14 associates with MAGOH in the exon junction complex, Y14's actions in the TNF-α-NF-κB pathway are unlikely to require MAGOH. Therefore, Y14 positively regulates signals for TNF-α-induced IL-6 production at multiple steps beyond an exon junction complex protein.
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Affiliation(s)
- Sumihito Togi
- Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
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Proximal microdeletions and microduplications of 1q21.1 contribute to variable abnormal phenotypes. Eur J Hum Genet 2012; 20:754-61. [PMID: 22317977 DOI: 10.1038/ejhg.2012.6] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Chromosomal band 1q21.1 can be divided into two distinct regions, proximal and distal, based on segmental duplications that mediate recurrent rearrangements. Microdeletions and microduplications of the distal region within 1q21.1, which are susceptibility factors for a variety of neurodevelopmental phenotypes, have been more extensively studied than proximal microdeletions and microduplications. Proximal microdeletions are known as a susceptibility factor for thrombocytopenia-absent radius (TAR) syndrome, but it is unclear if these proximal microdeletions have other phenotypic consequences. Therefore, to elucidate the clinical significance of rearrangements of the proximal 1q21.1 region, we evaluated the phenotypes in patients identified with 1q21.1 rearrangements after referral for clinical microarray testing. We report clinical information for 55 probands with copy number variations (CNVs) involving proximal 1q21.1: 22 microdeletions and 20 reciprocal microduplications limited to proximal 1q21.1 and 13 microdeletions that include both the proximal and distal regions. Six individuals with proximal microdeletions have TAR syndrome. Three individuals with proximal microdeletions and two individuals with larger microdeletions of proximal and distal 1q21.1 have a 'partial' TAR phenotype. Furthermore, one subject with TAR syndrome has a smaller, atypical deletion, narrowing the critical deletion region for the syndrome. Otherwise, phenotypic features varied among individuals with these microdeletions and microduplications. The recurrent, proximal 1q21.1 microduplications are enriched in our population undergoing genetic testing compared with control populations. Therefore, CNVs in proximal 1q21.1 can be a contributing factor for the development of abnormal phenotypes in some carriers.
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Zhao W, Zhou F, Zhou X, Hou Y, He Y, Cheng H, Zhou R. Mago, a vertebrate homolog of Drosophila Mago nashi protein, is a component of the chromatoid body in the cytoplasm of the postmeiotic spermatid. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2010; 314:232-41. [PMID: 19908226 DOI: 10.1002/jez.b.21331] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Post-transcriptional regulations play a crucial role during spermatogenesis of the vertebrates. Chromatoid body (CB) is a characteristic spermatid organelle that is supposed to exert its role in post-transcriptional processes, but its real functions remain largely unknown. Here we report identification of Mago from the rice field eel, and show its evolutionary conservation, differential expression and localization during gonadal transformation. The Mago interacts with Y14, which may facilitate nuclear export of both proteins in the Sertoli cells. Importantly, we have determined Mago as a novel component of the CB in the cytoplasm of the developing spermatid. Addition of Mago to the component list of the CB undoubtedly provides new clue as to the functions of the CB during spermatogenesis in the vertebrates.
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Affiliation(s)
- Wei Zhao
- Department of Genetics and Center for Developmental Biology, College of Life Science, Wuhan University, Wuhan, China
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22
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The identification, expression profile, and preliminary characterization of Tsunagi protein from Schistosoma japonicum. Parasitol Res 2010; 107:615-21. [PMID: 20467751 DOI: 10.1007/s00436-010-1904-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 04/29/2010] [Indexed: 10/19/2022]
Abstract
Tsunagi is an evolutionarily conserved protein, which is required for germ line differentiation during the development of Drosophila melanogaster and Caenorhabditis elegans. In this paper, we describe a homologue of the Tsunagi protein from Schistosoma japonicum (SjTsunagi). The gene for this protein was isolated from S. japonicum using degenerate and anchored polymerase chain reaction (PCR), and the deduced protein has sequence homology and similarity to Tsunagi protein of other species, including C. elegans, D. melanogaster, Xenopus laevis, Mus musculus, and human. Amino acid sequence analysis showed the presence of a conserved RNA recognition motif. The predicted protein encoded by SjTsunagi gene is 177 amino acids in length with an estimated molecular mass of 20 kD. Immunoblot and reverse transcription-PCR analysis confirms SjTsunagi protein is expressed in eggs, cercariae, schistosomula, and adult female and adult male parasites. Pull-down and co-immunoprecipitation assay confirms that protein of SjTsunagi can interact with SjMago nashi in vitro. Taken together, this is the first report of the expression and preliminary characterization analysis of the SjTsunagi gene from S. japonicum.
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