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Takeiwa T, Ikeda K, Horie K, Inoue S. Role of RNA binding proteins of the Drosophila behavior and human splicing (DBHS) family in health and cancer. RNA Biol 2024; 21:1-17. [PMID: 38551131 PMCID: PMC10984136 DOI: 10.1080/15476286.2024.2332855] [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] [Accepted: 03/15/2024] [Indexed: 04/02/2024] Open
Abstract
RNA-binding proteins (RBPs) play crucial roles in the functions and homoeostasis of various tissues by regulating multiple events of RNA processing including RNA splicing, intracellular RNA transport, and mRNA translation. The Drosophila behavior and human splicing (DBHS) family proteins including PSF/SFPQ, NONO, and PSPC1 are ubiquitously expressed RBPs that contribute to the physiology of several tissues. In mammals, DBHS proteins have been reported to contribute to neurological diseases and play crucial roles in cancers, such as prostate, breast, and liver cancers, by regulating cancer-specific gene expression. Notably, in recent years, multiple small molecules targeting DBHS family proteins have been developed for application as cancer therapeutics. This review provides a recent overview of the functions of DBHS family in physiology and pathophysiology, and discusses the application of DBHS family proteins as promising diagnostic and therapeutic targets for cancers.
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Affiliation(s)
- Toshihiko Takeiwa
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute for Geriatrics and Gerontology, Itabashi-ku, Tokyo, Japan
| | - Kazuhiro Ikeda
- Division of Systems Medicine & Gene Therapy, Faculty of Medicine, Saitama Medical University, Hidaka, Saitama, Japan
| | - Kuniko Horie
- Division of Systems Medicine & Gene Therapy, Faculty of Medicine, Saitama Medical University, Hidaka, Saitama, Japan
| | - Satoshi Inoue
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute for Geriatrics and Gerontology, Itabashi-ku, Tokyo, Japan
- Division of Systems Medicine & Gene Therapy, Faculty of Medicine, Saitama Medical University, Hidaka, Saitama, Japan
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Fonódi M, Thalwieser Z, Csortos C, Boratkó A. TIMAP, a Regulatory Subunit of Protein Phosphatase 1, Inhibits In Vitro Neuronal Differentiation. Int J Mol Sci 2023; 24:17360. [PMID: 38139189 PMCID: PMC10744335 DOI: 10.3390/ijms242417360] [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: 10/22/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
TIMAP (TGF-β-inhibited membrane associated protein) is abundant in endothelial cells, and it has been regarded as a member of the myosin phosphatase targeting protein (MYPT) family. Our workgroup previously identified several interacting protein partners of TIMAP and proved its regulatory subunit role for protein phosphatase 1 catalytic subunit (PP1c). TIMAP is also expressed in neuronal cells, but details of its function have not been studied yet. Therefore, we aimed to explore the role of TIMAP in neuronal cells, especially during differentiation. Expression of TIMAP was proved both at mRNA and protein levels in SH-SY5Y human neuroblastoma cells. Differentiation of SH-SY5Y cells was optimized and proved by the detection of neuronal differentiation markers, such as β3-tubulin, nestin and inhibitor of differentiation 1 (ID1) using qPCR and Western blot. We found downregulation of TIMAP during differentiation. In accordance with this, overexpression of recombinant TIMAP attenuated the differentiation of neuronal cells. Moreover, the subcellular localization of TIMAP has changed during differentiation as it translocated from the plasma membrane into the nucleus. The nuclear interactome of TIMAP revealed more than 50 proteins, offering the possibility to further investigate the role of TIMAP in several key physiological pathways of neuronal cells.
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Affiliation(s)
| | | | | | - Anita Boratkó
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Egyetem Tér 1, H-4032 Debrecen, Hungary; (M.F.); (Z.T.); (C.C.)
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3
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Maltseva D, Tonevitsky A. RNA-binding proteins regulating the CD44 alternative splicing. Front Mol Biosci 2023; 10:1326148. [PMID: 38106992 PMCID: PMC10722200 DOI: 10.3389/fmolb.2023.1326148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 11/15/2023] [Indexed: 12/19/2023] Open
Abstract
Alternative splicing is often deregulated in cancer, and cancer-specific isoform switches are part of the oncogenic transformation of cells. Accumulating evidence indicates that isoforms of the multifunctional cell-surface glycoprotein CD44 play different roles in cancer cells as compared to normal cells. In particular, the shift of CD44 isoforms is required for epithelial to mesenchymal transition (EMT) and is crucial for the maintenance of pluripotency in normal human cells and the acquisition of cancer stem cells phenotype for malignant cells. The growing and seemingly promising use of splicing inhibitors for treating cancer and other pathologies gives hope for the prospect of using such an approach to regulate CD44 alternative splicing. This review integrates current knowledge about regulating CD44 alternative splicing by RNA-binding proteins.
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Affiliation(s)
- Diana Maltseva
- Faculty of Biology and Biotechnology, HSE University, Moscow, Russia
| | - Alexander Tonevitsky
- Faculty of Biology and Biotechnology, HSE University, Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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4
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A novel splicing variant of DJ-1 in Parkinson's disease induces mitochondrial dysfunction. Heliyon 2023; 9:e14039. [PMID: 36915530 PMCID: PMC10006478 DOI: 10.1016/j.heliyon.2023.e14039] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 02/27/2023] Open
Abstract
Several studies have identified mutations in neuroprotective genes in a few cases of Parkinson's disease (PD); however, the role of alternative splicing changes in PD remains unelucidated. Based on the transcriptome analysis of substantia nigra (SN) tissues obtained from PD cases and age-matched healthy controls, we identified a novel alternative splicing variant of DJ-1, lacking exon 6 (DJ-1 ΔE6), frequently detected in the SN of patients with PD. We found that the exon 6 skipping of DJ-1 induces mitochondrial dysfunction and impaired antioxidant capability. According to an in silico modeling study, the exon 6 skipping of DJ-1 disrupts the structural state suitable for the oxidation of the cysteine 106 residue that is a prerequisite for activating its neuroprotective roles. Our results suggest that change in DJ-1 alternative splicing may contribute to PD progression and provide an insight for studying PD etiology and its potential therapeutic targets.
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Choi S, Lee HS, Cho N, Kim I, Cheon S, Park C, Kim EM, Kim W, Kim KK. RBFOX2-regulated TEAD1 alternative splicing plays a pivotal role in Hippo-YAP signaling. Nucleic Acids Res 2022; 50:8658-8673. [PMID: 35699208 PMCID: PMC9410899 DOI: 10.1093/nar/gkac509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 05/25/2022] [Accepted: 05/30/2022] [Indexed: 11/14/2022] Open
Abstract
Alternative pre-mRNA splicing is key to proteome diversity; however, the biological roles of alternative splicing (AS) in signaling pathways remain elusive. Here, we focus on TEA domain transcription factor 1 (TEAD1), a YAP binding factor in the Hippo signaling pathway. Public database analyses showed that expression of YAP-TEAD target genes negatively correlated with the expression of a TEAD1 isoform lacking exon 6 (TEAD1ΔE6) but did not correlate with overall TEAD1 expression. We confirmed that the transcriptional activity and oncogenic properties of the full-length TEAD1 isoform were greater than those of TEAD1ΔE6, with the difference in transcription related to YAP interaction. Furthermore, we showed that RNA-binding Fox-1 homolog 2 (RBFOX2) promoted the inclusion of TEAD1 exon 6 via binding to the conserved GCAUG element in the downstream intron. These results suggest a regulatory mechanism of RBFOX2-mediated TEAD1 AS and provide insight into AS-specific modulation of signaling pathways.
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Affiliation(s)
- Sunkyung Choi
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Hyo Seong Lee
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Namjoon Cho
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Inyoung Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Seongmin Cheon
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea.,Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - Chungoo Park
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Eun-Mi Kim
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Wantae Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Kee K Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
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SFPQ-ABL1 and BCR-ABL1 utilize different signalling networks to drive B-cell acute lymphoblastic leukaemia. Blood Adv 2022; 6:2373-2387. [PMID: 35061886 PMCID: PMC9006296 DOI: 10.1182/bloodadvances.2021006076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 01/10/2022] [Indexed: 11/25/2022] Open
Abstract
SFPQ-ABL1 is localized to the nuclear compartment and is a relatively weaker driver of cellular proliferation compared with BCR-ABL1. SFPQ-ABL1 and BCR-ABL1 activate distinct signaling networks, both of which converge on inhibiting apoptosis and driving proliferation.
Philadelphia-like (Ph-like) acute lymphoblastic leukemia (ALL) is a high-risk subtype of B-cell ALL characterized by a gene expression profile resembling Philadelphia chromosome–positive ALL (Ph+ ALL) in the absence of BCR-ABL1. Tyrosine kinase–activating fusions, some involving ABL1, are recurrent drivers of Ph-like ALL and are targetable with tyrosine kinase inhibitors (TKIs). We identified a rare instance of SFPQ-ABL1 in a child with Ph-like ALL. SFPQ-ABL1 expressed in cytokine-dependent cell lines was sufficient to transform cells and these cells were sensitive to ABL1-targeting TKIs. In contrast to BCR-ABL1, SFPQ-ABL1 localized to the nuclear compartment and was a weaker driver of cellular proliferation. Phosphoproteomics analysis showed upregulation of cell cycle, DNA replication, and spliceosome pathways, and downregulation of signal transduction pathways, including ErbB, NF-κB, vascular endothelial growth factor (VEGF), and MAPK signaling in SFPQ-ABL1–expressing cells compared with BCR-ABL1–expressing cells. SFPQ-ABL1 expression did not activate phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling and was associated with phosphorylation of G2/M cell cycle proteins. SFPQ-ABL1 was sensitive to navitoclax and S-63845 and promotes cell survival by maintaining expression of Mcl-1 and Bcl-xL. SFPQ-ABL1 has functionally distinct mechanisms by which it drives ALL, including subcellular localization, proliferative capacity, and activation of cellular pathways. These findings highlight the role that fusion partners have in mediating the function of ABL1 fusions.
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Lessard-Beaudoin M, M Gonzalez L, AlOtaibi M, Chouinard-Watkins R, Plourde M, Calon F, Graham RK. Diet enriched in omega-3 fatty acids alleviates olfactory system deficits in APOE4 transgenic mice. Eur J Neurosci 2021; 54:7092-7108. [PMID: 34549475 DOI: 10.1111/ejn.15472] [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: 05/11/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 11/30/2022]
Abstract
Olfactory dysfunction is observed in several neurological disorders including Mild Cognitive Impairment (MCI) and Alzheimer disease (AD). These deficits occur early and correlate with global cognitive performance, depression and degeneration of olfactory regions in the brain. Despite extensive human studies, there has been little characterization of the olfactory system in models of AD. In order to determine if olfactory structural and/or molecular phenotypes are observed in a model expressing a genetic risk factor for AD, we assessed the olfactory bulb (OB) in APOE4 transgenic mice. A significant decrease in OB weight was observed at 12 months of age in APOE4 mice concurrent with inflammation and decreased NeuN expression. In order to determine if a diet rich in omega-3s may alleviate the olfactory system phenotypes observed, we assessed WT and APOE4 mice on a docosahexaenoic acid (DHA) diet. APOE4 mice on a DHA diet did not present with atrophy of the OB, and the alterations in NeuN and IBA-1 expression were alleviated. Furthermore, alterations in caspase mRNA and protein expression in the APOE4 OB were not observed with a DHA diet. Similar to the human AD condition, OB atrophy is an early phenotype in the APOE4 mice and concurrent with inflammation. These data support a link between the structural olfactory brain region atrophy and the olfactory dysfunction observed in AD and suggest that inflammation and cell death pathways may contribute to the olfactory deficits observed. Furthermore, the results suggest that diets enriched in DHA may provide benefit to APOE4 allele carriers.
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Affiliation(s)
- Melissa Lessard-Beaudoin
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Pharmacology and Physiology, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Laura M Gonzalez
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Pharmacology and Physiology, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Majed AlOtaibi
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Pharmacology and Physiology, University of Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Raphaël Chouinard-Watkins
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Melanie Plourde
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Frederic Calon
- Faculty of Pharmacy, Centre de Recherche du CHU de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Rona K Graham
- Research Center on Aging, CIUSSS de L'Estrie - CHUS, Sherbrooke, Quebec, Canada.,Department of Pharmacology and Physiology, University of Sherbrooke, Sherbrooke, Quebec, Canada
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8
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Anderson MB, Das S, Miller KE. Subcellular localization of neuronal nuclei (NeuN) antigen in size and calcitonin gene-related peptide (CGRP) populations of dorsal root ganglion (DRG) neurons during acute peripheral inflammation. Neurosci Lett 2021; 760:135974. [PMID: 34146639 DOI: 10.1016/j.neulet.2021.135974] [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: 10/21/2020] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 10/21/2022]
Abstract
Pseudo-unipolar cell bodies of somatosensory primary neurons are located in the dorsal root ganglia (DRG). The somatic and peripheral domains of DRG neurons are often studied in sensory pain research to understand molecular mechanisms involved in the activation of pain and maintenance of inflammation. Adjuvant-induced arthritis (AIA) is an inflammatory model that elicits a robust and rapid onset immune response with a maximal swelling period of 24-48 h and persisting for several weeks. The AIA model in the hind paw of the rat elicits a potent inflammatory response of the dermis and epidermis, leading to protein expression changes for sensitization of many DRG neurons; however, it is unknown if the AIA model in the hind paw of the rat induces DRG neuronal injury, necrosis, or apoptosis at the somatic level. Neuronal nuclei (NeuN) antigen is a biomarker for post-mitotic neurons, neuronal identification, protein alterations, injury, and loss. Calcitonin gene-related peptide (CGRP) is expressed in C and Aδ DRG neurons, a subset of DRG neurons known to play a role in peripheral sensitization. The focus of this research was to evaluate the expression pattern of NeuN immunoreactivity, in size (soma) and CGRP subpopulations of DRG neurons in naïve and inflamed groups. Confirmed by both immunofluorescence and immunoprecipitation, DRG neuronal expression of NeuN was localized to nuclear and cytoplasmic subcellular compartments. NeuN increased within the nucleus of small CGRP positive DRG neurons during inflammation, indicating a potential role for NeuN in a subset of nociceptive neurons.
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Affiliation(s)
- Michael B Anderson
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1).
| | - Subhas Das
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1)
| | - Kenneth E Miller
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1)
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9
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Katano-Toki A, Yoshino S, Nakajima Y, Tomaru T, Nishikido A, Ishida E, Horiguchi K, Saito T, Ozawa A, Satoh T, Yamada M. SFPQ associated with a co-activator for PPARγ, HELZ2, regulates key nuclear factors for adipocyte differentiation. Biochem Biophys Res Commun 2021; 562:139-145. [PMID: 34052659 DOI: 10.1016/j.bbrc.2021.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 05/06/2021] [Indexed: 12/14/2022]
Abstract
We recently isolated a novel co-activator of peroxisome proliferator-activated receptor γ, helicase with zinc finger 2 (HELZ2). HELZ2 null mice were resistant to diet-induced obesity and NAFFL/NASH, and HELZ2 was phosphorylated at tyrosine residues. In order to find a factor related to HELZ2, we analyzed products co-immunoprecipitated with phosphorylated HELZ2 by mass spectrometry analyses. We identified proline- and glutamine-rich (SFPQ) as a protein associating with tyrosine-phosphorylated HELZ2. The knockdown of SFPQ in 3T3-L1 cells downregulated mRNA levels of transcription factors including Krox20, Cebpβ, and Cebpδ: key factors for early-stage adipocyte differentiation. In addition, knockdown of SFPQ inhibited 3T3-L1 cell differentiation to mature adipocytes. These findings demonstrated that SFPQ associating with HELZ2 is an important novel transcriptional regulator of adipocyte differentiation.
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Affiliation(s)
- Akiko Katano-Toki
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan.
| | - Satoshi Yoshino
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Yasuyo Nakajima
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Takuya Tomaru
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Ayaka Nishikido
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Emi Ishida
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Kazuhiko Horiguchi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Tsugumichi Saito
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Atsushi Ozawa
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Tetsurou Satoh
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Masanobu Yamada
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
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Gordon PM, Hamid F, Makeyev EV, Houart C. A conserved role for the ALS-linked splicing factor SFPQ in repression of pathogenic cryptic last exons. Nat Commun 2021; 12:1918. [PMID: 33771997 PMCID: PMC7997972 DOI: 10.1038/s41467-021-22098-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 02/24/2021] [Indexed: 12/13/2022] Open
Abstract
The RNA-binding protein SFPQ plays an important role in neuronal development and has been associated with several neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease. Here, we report that loss of sfpq leads to premature termination of multiple transcripts due to widespread activation of previously unannotated cryptic last exons (CLEs). These SFPQ-inhibited CLEs appear preferentially in long introns of genes with neuronal functions and can dampen gene expression outputs and/or give rise to short peptides interfering with the normal gene functions. We show that one such peptide encoded by the CLE-containing epha4b mRNA isoform is responsible for neurodevelopmental defects in the sfpq mutant. The uncovered CLE-repressive activity of SFPQ is conserved in mouse and human, and SFPQ-inhibited CLEs are found expressed across ALS iPSC-derived neurons. These results greatly expand our understanding of SFPQ function and uncover a gene regulation mechanism with wide relevance to human neuropathologies.
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Affiliation(s)
- Patricia M Gordon
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Guy's Campus, King's College London, London, SE1 1UL, UK.
| | - Fursham Hamid
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Guy's Campus, King's College London, London, SE1 1UL, UK
| | - Eugene V Makeyev
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Guy's Campus, King's College London, London, SE1 1UL, UK
| | - Corinne Houart
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Guy's Campus, King's College London, London, SE1 1UL, UK.
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Zhang H, Wang Y, Zhang W, Wu Q, Fan J, Zhan Q. BAALC-AS1/G3BP2/c-Myc feedback loop promotes cell proliferation in esophageal squamous cell carcinoma. Cancer Commun (Lond) 2021; 41:240-257. [PMID: 33476486 PMCID: PMC7968881 DOI: 10.1002/cac2.12127] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/22/2020] [Accepted: 12/16/2020] [Indexed: 12/15/2022] Open
Abstract
Background Long non‐coding RNAs (lncRNAs) have been found to be involved in the development of many cancers. In this study, we aimed to identify the molecular mechanisms of lncRNA BAALC antisense RNA 1 (BAALC‐AS1) in regulating the malignancy of esophageal squamous cell carcinoma (ESCC). Methods The expression of BAALC‐AS1 in cancer patients was analyzed using a tissue microarray. The protein and RNA levels of BAALC‐AS1 were determined by Western blotting analysis and quantitative reverse transcription‐PCR (RT‐qPCR), respectively. The cell proliferation was determined by cell viability assays, bromodeoxyuridine incorporation, and flow cytometry. The relationships among BAALC‐AS1, RasGAPSH3 domain‐binding protein 2 (G3BP2), and c‐Myc were determined using RNA immunoprecipitation, RNA pull‐down assays, and luciferase assays. Results The expression of BAALC‐AS1 was highly up‐regulated and associated with malignant phenotypes in ESCC tissues and cell lines. In vivo and in vitro assays showed that BAALC‐AS1 promoted ESCC cell proliferation, migration, and invasion. BAALC‐AS1 directly interacted with G3BP2, and thereby inhibited the degradation of c‐Myc RNA 3'‐UTR by G3BP2, thus leading to the accumulation of c‐Myc expression. Additionally, c‐Myc acted as a transcription factor that can induce the expression of BAALC‐AS1 by directly binding to its promoter region. Conclusions BAALC‐AS1/G3BP2/c‐Myc feedback loop plays a critical role in the development of ESCC, which might provide a novel therapeutic target and facilitate the development of new therapeutic strategies for the treatment of ESCC.
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Affiliation(s)
- Hongyue Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China
| | - Yan Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China
| | - Weimin Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China
| | - Qingnan Wu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China
| | - Jiawen Fan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China
| | - Qimin Zhan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China.,Shenzhen Bay Laboratory, Shenzhen, Guangdong, 518132, P. R. China
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12
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Gilloteaux J, Bouchat J, Brion JP, Nicaise C. The osmotic demyelination syndrome: the resilience of thalamic neurons is verified with transmission electron microscopy. Ultrastruct Pathol 2021; 44:450-480. [DOI: 10.1080/01913123.2020.1853865] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jacques Gilloteaux
- Unit of Research in Molecular Physiology (Urphym- NARILIS), Department of Medicine, Université de Namur, Namur, Belgium
- Department of Anatomical Sciences, St George’s University School of Medicine, KB Taylor Global Scholar’s Program at UNN, School of Health and Life Sciences, Newcastle upon Tyne, UK
| | - Joanna Bouchat
- Unit of Research in Molecular Physiology (Urphym- NARILIS), Department of Medicine, Université de Namur, Namur, Belgium
| | - Jean-Pierre Brion
- Laboratory of Histology, Neuroanatomy and Neuropathology, Faculté de Médecine Université Libre de Bruxelles, Brussels, Belgium
| | - Charles Nicaise
- Unit of Research in Molecular Physiology (Urphym- NARILIS), Department of Medicine, Université de Namur, Namur, Belgium
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13
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The Emerging Role of the RNA-Binding Protein SFPQ in Neuronal Function and Neurodegeneration. Int J Mol Sci 2020; 21:ijms21197151. [PMID: 32998269 PMCID: PMC7582472 DOI: 10.3390/ijms21197151] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
RNA-binding proteins (RBPs) are a class of proteins known for their diverse roles in RNA biogenesis, from regulating transcriptional processes in the nucleus to facilitating translation in the cytoplasm. With higher demand for RNA metabolism in the nervous system, RBP misregulation has been linked to a wide range of neurological and neurodegenerative diseases. One of the emerging RBPs implicated in neuronal function and neurodegeneration is splicing factor proline- and glutamine-rich (SFPQ). SFPQ is a ubiquitous and abundant RBP that plays multiple regulatory roles in the nucleus such as paraspeckle formation, DNA damage repair, and various transcriptional regulation processes. An increasing number of studies have demonstrated the nuclear and also cytoplasmic roles of SFPQ in neurons, particularly in post-transcriptional regulation and RNA granule formation. Not surprisingly, the misregulation of SFPQ has been linked to pathological features shown by other neurodegenerative disease-associated RBPs such as aberrant RNA splicing, cytoplasmic mislocalization, and aggregation. In this review, we discuss recent findings on the roles of SFPQ with a particular focus on those in neuronal development and homeostasis as well as its implications in neurodegenerative diseases.
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14
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Murine Long Noncoding RNA Morrbid Contributes in the Regulation of NRAS Splicing in Hepatocytes In Vitro. Int J Mol Sci 2020; 21:ijms21165605. [PMID: 32764370 PMCID: PMC7460575 DOI: 10.3390/ijms21165605] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/19/2022] Open
Abstract
The coupling of alternative splicing with the nonsense-mediated decay (NMD) pathway maintains quality control of the transcriptome in eukaryotes by eliminating transcripts with premature termination codons (PTC) and fine-tunes gene expression. Long noncoding RNA (lncRNA) can regulate multiple cellular processes, including alternative splicing. Previously, murine Morrbid (myeloid RNA repressor of Bcl2l11 induced death) lncRNA was described as a locus-specific controller of the lifespan of short-living myeloid cells via transcription regulation of the apoptosis-related Bcl2l11 protein. Here, we report that murine Morrbid lncRNA in hepatocytes participates in the regulation of proto-oncogene NRAS (neuroblastoma RAS viral oncogene homolog) splicing, including the formation of the isoform with PTC. We observed a significant increase of the NRAS isoform with PTC in hepatocytes with depleted Morrbid lncRNA. We demonstrated that the NRAS isoform with PTC is degraded via the NMD pathway. This transcript is presented almost only in the nucleus and has a half-life ~four times lower than other NRAS transcripts. Additionally, in UPF1 knockdown hepatocytes (the key NMD factor), we observed a significant increase of the NRAS isoform with PTC. By a modified capture hybridization (CHART) analysis of the protein targets, we uncovered interactions of Morrbid lncRNA with the SFPQ (splicing factor proline and glutamine rich)-NONO (non-POU domain-containing octamer-binding protein) splicing complex. Finally, we propose the regulation mechanism of NRAS splicing in murine hepatocytes by alternative splicing coupled with the NMD pathway with the input of Morrbid lncRNA.
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15
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Laroche M, Lessard-Beaudoin M, Garcia-Miralles M, Kreidy C, Peachey E, Leavitt BR, Pouladi MA, Graham RK. Early deficits in olfaction are associated with structural and molecular alterations in the olfactory system of a Huntington disease mouse model. Hum Mol Genet 2020; 29:2134-2147. [PMID: 32436947 DOI: 10.1093/hmg/ddaa099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/25/2020] [Accepted: 05/12/2020] [Indexed: 12/22/2022] Open
Abstract
Olfactory dysfunction and altered neurogenesis are observed in several neurodegenerative disorders including Huntington disease (HD). These deficits occur early and correlate with a decline in global cognitive performance, depression and structural abnormalities of the olfactory system including the olfactory epithelium, bulb and cortices. However, the role of olfactory system dysfunction in the pathogenesis of HD remains poorly understood and the mechanisms underlying this dysfunction are unknown. We show that deficits in odour identification, discrimination and memory occur in HD individuals. Assessment of the olfactory system in an HD murine model demonstrates structural abnormalities in the olfactory bulb (OB) and piriform cortex, the primary cortical recipient of OB projections. Furthermore, a decrease in piriform neuronal counts and altered expression levels of neuronal nuclei and tyrosine hydroxylase in the OB are observed in the YAC128 HD model. Similar to the human HD condition, olfactory dysfunction is an early phenotype in the YAC128 mice and concurrent with caspase activation in the murine HD OB. These data provide a link between the structural olfactory brain region atrophy and olfactory dysfunction in HD and suggest that cell proliferation and cell death pathways are compromised and may contribute to the olfactory deficits in HD.
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Affiliation(s)
- M Laroche
- Research Center on Aging, CIUSSS-IUGS de l'Estrie-CHUS, FMSS, Department of Pharmacology and Physiology, University of Sherbrooke, Quebec J1K 2R1, Canada
| | - M Lessard-Beaudoin
- Research Center on Aging, CIUSSS-IUGS de l'Estrie-CHUS, FMSS, Department of Pharmacology and Physiology, University of Sherbrooke, Quebec J1K 2R1, Canada
| | - M Garcia-Miralles
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research (ASTAR), Singapore 138632
| | - C Kreidy
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research (ASTAR), Singapore 138632
| | - E Peachey
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - B R Leavitt
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - M A Pouladi
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research (ASTAR), Singapore 138632.,Departments of Medicine and Physiology, National University of Singapore, Singapore 119077
| | - R K Graham
- Research Center on Aging, CIUSSS-IUGS de l'Estrie-CHUS, FMSS, Department of Pharmacology and Physiology, University of Sherbrooke, Quebec J1K 2R1, Canada
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16
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Slomianka L. Basic quantitative morphological methods applied to the central nervous system. J Comp Neurol 2020; 529:694-756. [PMID: 32639600 PMCID: PMC7818269 DOI: 10.1002/cne.24976] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 12/19/2022]
Abstract
Generating numbers has become an almost inevitable task associated with studies of the morphology of the nervous system. Numbers serve a desire for clarity and objectivity in the presentation of results and are a prerequisite for the statistical evaluation of experimental outcomes. Clarity, objectivity, and statistics make demands on the quality of the numbers that are not met by many methods. This review provides a refresher of problems associated with generating numbers that describe the nervous system in terms of the volumes, surfaces, lengths, and numbers of its components. An important aim is to provide comprehensible descriptions of the methods that address these problems. Collectively known as design‐based stereology, these methods share two features critical to their application. First, they are firmly based in mathematics and its proofs. Second and critically underemphasized, an understanding of their mathematical background is not necessary for their informed and productive application. Understanding and applying estimators of volume, surface, length or number does not require more of an organizational mastermind than an immunohistochemical protocol. And when it comes to calculations, square roots are the gravest challenges to overcome. Sampling strategies that are combined with stereological probes are efficient and allow a rational assessment if the numbers that have been generated are “good enough.” Much may be unfamiliar, but very little is difficult. These methods can no longer be scapegoats for discrepant results but faithfully produce numbers on the material that is assessed. They also faithfully reflect problems that associated with the histological material and the anatomically informed decisions needed to generate numbers that are not only valid in theory. It is within reach to generate practically useful numbers that must integrate with qualitative knowledge to understand the function of neural systems.
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Affiliation(s)
- Lutz Slomianka
- University of Zürich, Institute of Anatomy, Zürich, Switzerland
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17
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Luo C, Zhu X, Luo Q, Bu F, Huang C, Zhu J, Zhao J, Zhang W, Lin K, Hu C, Zong Z, Luo H, Huang J, Zhu Z. RBFOX3 Promotes Gastric Cancer Growth and Progression by Activating HTERT Signaling. Front Oncol 2020; 10:1044. [PMID: 32903312 PMCID: PMC7396657 DOI: 10.3389/fonc.2020.01044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 05/26/2020] [Indexed: 12/30/2022] Open
Abstract
Tumor invasion, metastasis, and recrudescence remain a considerable challenge in the treatment of gastric cancer (GC). Herein we first identified that RNA binding protein fox-1 homolog 3 (RBFOX3) was markedly overexpressed in GC tissues and negatively linked to the survival rate of GC patients. RBFOX3 promoted cell division and cell cycle progression in vitro and in vivo. Furthermore, RBFOX3 increased the cell invasion and migration ability. The suppression of GC cell multiplication and invasion, caused by silencing of RBFOX3, was rescued by HTERT overexpression. Additionally, RBFOX3 augmented the resistance of GC cells to 5-fluorouracil by repressing RBFOX3. Mechanistically, the exogenous up-regulation of RBFOX3 triggered promoter activity and HTERT expression, thereby enhancing the division and the development of GC cells. Further co-immunoprecipitation tests revealed that RBFOX3 bound to AP-2β to modulate HTERT expression. In conclusion, our study indicates that a high expression of RBFOX3 promotes GC progression and development and predicts worse prognosis. Collectively, these results indicate that the RBFOX3/AP-2β/HTERT signaling pathway can be therapeutically targeted to prevent and treat GC recurrence and metastasis.
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Affiliation(s)
- Chen Luo
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Xiaojian Zhu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Qilin Luo
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Fanqin Bu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Chao Huang
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Jingfeng Zhu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Jiefeng Zhao
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Wenjun Zhang
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Kang Lin
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Cegui Hu
- Department of Clinical Medical, Jiangxi Medical College of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Zeng Zong
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Hongliang Luo
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China.,Jiangxi Province Key Laboratory of Molecular Medicine, Nanchang, China
| | - Jun Huang
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zhengming Zhu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
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18
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Song H, Wang Y, Wang R, Zhang X, Liu Y, Jia G, Chen PR. SFPQ Is an FTO-Binding Protein that Facilitates the Demethylation Substrate Preference. Cell Chem Biol 2020; 27:283-291.e6. [PMID: 31981477 DOI: 10.1016/j.chembiol.2020.01.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/15/2019] [Accepted: 01/03/2020] [Indexed: 12/25/2022]
Abstract
The fat mass and obesity-associated protein (FTO) is the first identified demethylase of the internal RNA modification N6-methyladenosine (m6A), which also exhibits demethylation activity toward N6,2'-O-dimethyladenosine (m6Am) and N1-methyladenosine (m1A). Demethylation of m6A at specific sites on target transcripts is a key enzymatic function of FTO that modulates diverse physiological and/or pathological processes. However, how FTO selects target RNA and whether additional interaction proteins facilitate this process remain elusive. Herein, via the genetically encoded and site-specific photocrosslinking strategy, we identified the major RNA-binding protein SFPQ as a direct interaction partner of FTO. Our study showed that FTO and SFPQ were located in close proximity throughout the transcriptome and that overexpression of SFPQ led to the demethylation of adjacent m6As, likely through recruiting FTO to these specific RNA sites. These results uncovered a new layer of regulation mechanism that may assist FTO to gain substrate specificity.
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Affiliation(s)
- Haiping Song
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Ye Wang
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Ruixiang Wang
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - Xiao Zhang
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Yaping Liu
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Guifang Jia
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
| | - Peng R Chen
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Beijing 100871, China.
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19
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Saito K, Koike T, Kawashima F, Kurata H, Shibuya T, Satoh T, Hata Y, Yamada H, Mori T. Identification of NeuN immunopositive cells in the adult mouse subventricular zone. J Comp Neurol 2019; 526:1927-1942. [PMID: 29752725 DOI: 10.1002/cne.24463] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/18/2018] [Accepted: 04/30/2018] [Indexed: 11/06/2022]
Abstract
In the adult rodent subventricular zone (SVZ), there are neural stem cells (NSCs) and the specialized neurogenic niche is critical to maintain their stemness. To date, many cellular and noncellular factors that compose the neurogenic niche and markers to identify subpopulations of Type A cells have been confirmed. In particular, neurotransmitters regulate adult neurogenesis and mature neurons in the SVZ have been only partially analyzed. Moreover, Type A cells, descendants of NSCs, are highly heterogeneous and more molecular markers are still needed to identify them. In the present study, we systematically classified NeuN, commonly used as a marker of mature and immature post-mitotic neurons, immunopositive (+) cells within the adult mouse SVZ. These SVZ-NeuN+ cells (SVZ-Ns) were mainly classified into two types. One was mature SVZ-Ns (M-SVZ-Ns). Neurochemical properties of M-SVZ-Ns were similar to those of striatal neurons, but their birth date and morphology were different. M-SVZ-Ns were generated during embryonic and early postnatal stages with bipolar peaks and extended their processes along the wall of the lateral ventricle. The second type was small SVZ-Ns (S-SVZ-Ns) with features of Type A cells. They expressed not only markers of Type A cells, but also proliferated and migrated from the SVZ to the olfactory bulb. Furthermore, S-SVZ-Ns could be classified into two types by their spatial locations and glutamic acid decarboxylase 67 expression. Our data indicate that M-SVZ-Ns are a new component of the neurogenic niche and S-SVZ-Ns are newly identified subpopulations of Type A cells.
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Affiliation(s)
- Kengo Saito
- Department of Biological Regulation, School of Health Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Taro Koike
- Department of Anatomy and Cell Science, Kansai Medical University, Hirakata, Osaka, Japan
| | - Fumiaki Kawashima
- Department of Biological Regulation, School of Health Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Hirofumi Kurata
- Department of Biological Regulation, School of Health Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.,Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Taku Shibuya
- Division of Integrative Bioscience, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Takemasa Satoh
- Division of Neurobiology, School of Life Sciences, Faculty of Medicine, Tottori University Yonago, Japan
| | - Yoshio Hata
- Division of Integrative Bioscience, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Sciences, Yonago, Japan.,Division of Neurobiology, School of Life Sciences, Faculty of Medicine, Tottori University Yonago, Japan
| | - Hisao Yamada
- Department of Anatomy and Cell Science, Kansai Medical University, Hirakata, Osaka, Japan
| | - Tetsuji Mori
- Department of Biological Regulation, School of Health Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
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20
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Nikonova E, Kao SY, Ravichandran K, Wittner A, Spletter ML. Conserved functions of RNA-binding proteins in muscle. Int J Biochem Cell Biol 2019; 110:29-49. [PMID: 30818081 DOI: 10.1016/j.biocel.2019.02.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 02/21/2019] [Accepted: 02/23/2019] [Indexed: 12/13/2022]
Abstract
Animals require different types of muscle for survival, for example for circulation, motility, reproduction and digestion. Much emphasis in the muscle field has been placed on understanding how transcriptional regulation generates diverse types of muscle during development. Recent work indicates that alternative splicing and RNA regulation are as critical to muscle development, and altered function of RNA-binding proteins causes muscle disease. Although hundreds of genes predicted to bind RNA are expressed in muscles, many fewer have been functionally characterized. We present a cross-species view summarizing what is known about RNA-binding protein function in muscle, from worms and flies to zebrafish, mice and humans. In particular, we focus on alternative splicing regulated by the CELF, MBNL and RBFOX families of proteins. We discuss the systemic nature of diseases associated with loss of RNA-binding proteins in muscle, focusing on mis-regulation of CELF and MBNL in myotonic dystrophy. These examples illustrate the conservation of RNA-binding protein function and the marked utility of genetic model systems in understanding mechanisms of RNA regulation.
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Affiliation(s)
- Elena Nikonova
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Shao-Yen Kao
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Keshika Ravichandran
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Anja Wittner
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Maria L Spletter
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany; Center for Integrated Protein Science Munich (CIPSM) at the Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany.
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21
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Ma F, Dong Z, Berberoglu MA. Expression of RNA-binding protein Rbfox1l demarcates a restricted population of dorsal telencephalic neurons within the adult zebrafish brain. Gene Expr Patterns 2019; 31:32-41. [PMID: 30634066 DOI: 10.1016/j.gep.2019.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/22/2018] [Accepted: 01/04/2019] [Indexed: 01/16/2023]
Abstract
Rbfox RNA-binding proteins are expressed in the adult mammalian brain and are required for proper brain development and function. Studies in mice and humans have implicated Rbfox1/RBFOX1 in autism, neuronal excitation and epilepsy, and Rbfox2/RBFOX2 in cerebellar development. The zebrafish has emerged as a prominent model system for brain study, possessing neuroanatomical conservation with mammals and an extensive capacity for adult neurogenesis and plasticity. In this study, we characterize Rbfox1l and Rbfox2 expression in the adult zebrafish brain. While Rbfox2 is expressed broadly, Rbfox1l is expressed in restricted populations of neurons in the dorsal telencephalon and cerebellum. In the dorsal telencephalon, Rbfox1l is expressed in a specific population of neurons spanning Dm and Dc regions. In the cerebellum, Rbfox1l and Rbfox2 are expressed in the Purkinje cell layer, reminiscent of Rbfox1 and Rbfox2 expression in the mammalian cerebellum. Our findings motivate future studies of Rbfox function in the zebrafish brain.
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Affiliation(s)
- Fengjun Ma
- Bio-Medical Center, College of Life Science & Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Zhiqiang Dong
- Bio-Medical Center, College of Life Science & Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Michael A Berberoglu
- Bio-Medical Center, College of Life Science & Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China; Department of Molecular Genetics, The Ohio State University, Columbus, OH, 43210, USA; Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA; Center for Muscle Health and Neuromuscular Disorders, The Ohio State University, Nationwide Children's Hospital, Columbus, OH, 43210, USA.
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22
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Kim YE, Park C, Kim KE, Kim KK. Histone and RNA-binding protein interaction creates crosstalk network for regulation of alternative splicing. Biochem Biophys Res Commun 2018; 499:30-36. [PMID: 29551686 DOI: 10.1016/j.bbrc.2018.03.101] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 03/13/2018] [Indexed: 12/18/2022]
Abstract
Alternative splicing is an essential process in eukaryotes, as it increases the complexity of gene expression by generating multiple proteins from a single pre-mRNA. However, information on the regulatory mechanisms for alternative splicing is lacking, because splicing occurs over a short period via the transient interactions of proteins within functional complexes of the spliceosome. Here, we investigated in detail the molecular mechanisms connecting alternative splicing with epigenetic mechanisms. We identified interactions between histone proteins and splicing factors such as Rbfox2, Rbfox3, and splicing factor proline and glutamine rich protein (SFPQ) by in vivo crosslinking and immunoprecipitation. Furthermore, we confirmed that splicing factors were bound to specific modified residues of histone proteins. Additionally, changes in histone methylation due to histone methyltransferase inhibitor treatment notably affected alternative splicing in selected genes. Therefore, we suggested that there may be crosstalk mechanisms connecting histone modifications and RNA-binding proteins that increase the local concentration of RNA-binding proteins in alternative exon loci of nucleosomes by binding specific modified histone proteins, leading to alternative splicing. This crosstalk mechanism may play a major role in epigenetic processes such as histone modification and the regulation of alternative splicing.
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Affiliation(s)
- Yong-Eun Kim
- Department of Biochemistry, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Chungoo Park
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Kyoon Eon Kim
- Department of Biochemistry, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Kee K Kim
- Department of Biochemistry, Chungnam National University, Daejeon, 34134, Republic of Korea.
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23
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Choi S, Kim YE, Kim JW, Cho N, Cheon S, Kim KK. Rbfox family proteins make the homo- and hetero-oligomeric complexes. Biochem Biophys Res Commun 2018; 495:1022-1027. [PMID: 29170129 DOI: 10.1016/j.bbrc.2017.11.128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 11/19/2017] [Indexed: 12/17/2022]
Abstract
Rbfox family of proteins that consists of Rbfox1, Rbfox2, and Rbfox3 in mammals regulates alternative pre-mRNA splicing in various tissues via direct binding to their RNA binding element. Although many studies have indicated the splicing activity of each member of the Rbfox family, the interactions of Rbfox family proteins are largely unknown. Here, we have investigated interactions among Rbfox family proteins. Co-immunoprecipitation (Co-IP) and GST-pull down assays confirmed that Rbfox proteins form homo and hetero complexes. Moreover, in vivo crosslinking using disuccinimidyl suberate treatment indicated that the Rbfox proteins form a dimer which then assembles with other proteins to form a large multiprotein complex. Duolink in situ proximity ligation (PLA) assay revealed that neuron specific Rbfox3 protein interacts with other Rbfox family proteins. This study is the first to provide an evidence that Rbfox family proteins form homo- and hetero-oligomeric complexes in vivo.
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Affiliation(s)
- Sunkyung Choi
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Yong-Eun Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jae Whan Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Namjoon Cho
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Seonghye Cheon
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Kee K Kim
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Republic of Korea.
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24
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Meta-analysis of genome-wide association studies on the intolerance of angiotensin-converting enzyme inhibitors. Pharmacogenet Genomics 2017; 27:112-119. [PMID: 28030426 DOI: 10.1097/fpc.0000000000000264] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To identify single nucleotide polymorphisms (SNPs) associated with switching from an angiotensin-converting enzyme (ACE)-inhibitor to an angiotensin receptor blocker. METHODS Two cohorts of patients starting ACE-inhibitors were identified within the Rotterdam Study in the Netherlands and the Genetics of Diabetes Audit and Research in Tayside Scotland study in Scotland. Cases were intolerant patients who switched from an ACE-inhibitor to an angiotensin receptor blocker and controls were individuals who used ACE-inhibitors continuously for at least 2 years and did not switch. Genome-wide association study (GWAS) using an additive model was run in these sets and the results were meta-analysed using Genome-Wide Association Meta Analysis software. RESULTS A total of 972 cases out of 5161 ACE-inhibitor starters were identified. Eight SNPs within four genes reached the genome-wide association study significance level (P<5×10) in the meta-analysis [RNA binding protein, Fox-1 homolog (Caenorhabditis elegans), γ-aminobutyric acid receptor subunit γ-2, sarcoma (Src) homology 2 (SH2) B adaptor protein 1 and membrane bound O-acyltransferase domain containing 1]. The strongest associated SNP was located in an intron of RNA binding protein, Fox-1 homolog (Caenorhabditis elegans), which contains an RNA binding protein [rs2061538: minor allele frequency=0.16, odds ratio=1.52 (95% confidence interval: 1.32-1.76), P=6.2×10]. CONCLUSION These results indicate that genetic variation in the above-mentioned genes may increase the risk of ACE-inhibitor-induced adverse reactions.
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Stress Granules Contain Rbfox2 with Cell Cycle-related mRNAs. Sci Rep 2017; 7:11211. [PMID: 28894257 PMCID: PMC5593835 DOI: 10.1038/s41598-017-11651-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/25/2017] [Indexed: 01/02/2023] Open
Abstract
Rbfox RNA-binding proteins play important roles in the regulation of alternative pre-mRNA splicing, but their role in other gene regulatory mechanisms is not well understood. Here, we show that Rbfox2 is a novel constituent of cytoplasmic stress granules, the translational silencing machinery assembled in response to cellular stress. We also show that the RNA binding activity of the Rbfox family protein is crucial for its localization into stress granules. To investigate the role of Rbfox2 in stress granules we used RNA-immunoprecipitation sequencing to identify cytoplasmic transcriptome-wide targets of Rbfox2. We report that a subset of cell cycle-related genes including retinoblastoma 1 is the target of Rbfox2 in cytoplasmic stress granules, and Rbfox2 regulates the retinoblastoma 1 mRNA and protein expression levels during and following stress exposure. Our study proposes a novel function for Rbfox2 in cytoplasmic stress granules.
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Partridge LMM, Carter DA. Novel Rbfox2 isoforms associated with alternative exon usage in rat cortex and suprachiasmatic nucleus. Sci Rep 2017; 7:9929. [PMID: 28855650 PMCID: PMC5577181 DOI: 10.1038/s41598-017-10535-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 08/09/2017] [Indexed: 12/20/2022] Open
Abstract
Transcriptome diversity in adult neurons is partly mediated by RNA binding proteins (RBPs), including the RBFOX factors. RBFOX3/NeuN, a neuronal maturity marker, is strangely depleted in suprachiasmatic nucleus (SCN) neurons, and may be compensated by a change in Rbfox2 expression. In this study, we found no superficial changes in Rbfox2 expression in the SCN, but mRNA population analysis revealed a distinct SCN transcript profile that includes multiple novel Rbfox2 isoforms. Of eleven isoforms in SCN and cerebral cortex that exhibit exon variation across two protein domains, we found a 3-fold higher abundance of a novel (‘−12–40’) C-terminal domain (CTD)-variant in the SCN. This isoform embraces an alternative reading frame that imparts a 50% change in CTD protein sequence, and functional impairment of exon 7 exclusion activity in a RBFOX2-target, the L-type calcium channel gene, Cacna1c. We have also demonstrated functional correlates in SCN gene transcripts; inclusion of Cacna1c exon 7, and also exclusion of both NMDA receptor gene Grin1 exon 4, and Enah exon 12, all consistent with a change in SCN RBFOX activity. The demonstrated regional diversity of Rbfox2 in adult brain highlights the functional adaptability of this RBP, enabling neuronal specialization, and potentially responding to disease-related neuronal dysfunction.
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Affiliation(s)
| | - D A Carter
- School of Biosciences, Cardiff University, Cardiff, UK.
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SFPQ, a multifunctional nuclear protein, regulates the transcription of PDE3A. Biosci Rep 2017; 37:BSR20170975. [PMID: 28743736 PMCID: PMC5548871 DOI: 10.1042/bsr20170975] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/22/2017] [Accepted: 07/25/2017] [Indexed: 11/30/2022] Open
Abstract
Phosphodiesterase 3A (PDE3A), a member of the cGMP-inhibited cyclic nucleotide phosphodiesterase (PDE) family, plays important roles in oocyte maturation and vascular smooth muscle cell proliferation. However, the molecular mechanisms that regulate PDE3A gene expression remain largely unknown. In the present study, we investigated the transcriptional regulation of PDE3A, and found that the splicing factor proline- and glutamine-rich (SFPQ) protein modulated PDE3A mRNA levels. Multiple transcription start sites (TSS1, 2, and 3) were identified within the first exon of PDE3A using 5′-rapid amplification of cDNA ends (RACE). Variable expression levels of three PDE3A variants were also observed in human tissues and HeLa cells. Several putative SFPQ-binding sites were identified upstream of the regulatory region of PDE3A-TSSs using ChIP sequencing (ChIP-seq). Serum-induced PDE3A expression was affected by increasing the amount of SFPQ binding to the upstream regulatory region of PDE3A. In addition, transcription of PDE3A was lower in human cervical adenocarcinoma cells compared with normal cervical tissue. Furthermore, overexpression of PDE3A induced sensitivity to anticancer therapeutic agent, 6-(4-(diethylamino)-3-nitrophenyl)-5-methyl-4,5-dihydropyridazin-3(2H)-one (DNMDP), in HeLa cells. Taken together, these results suggest that SFPQ functions as a transcriptional activator of PDE3A, which is involved in the regulation of DNMDP sensitivity, offering a novel molecular target for the development of anticancer therapies.
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Liu T, Li W, Lu W, Chen M, Luo M, Zhang C, Li Y, Qin G, Shi D, Xiao B, Qiu H, Yu W, Kang L, Kang T, Huang W, Yu X, Wu X, Deng W. RBFOX3 Promotes Tumor Growth and Progression via hTERT Signaling and Predicts a Poor Prognosis in Hepatocellular Carcinoma. Am J Cancer Res 2017; 7:3138-3154. [PMID: 28839469 PMCID: PMC5566111 DOI: 10.7150/thno.19506] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 05/19/2017] [Indexed: 12/18/2022] Open
Abstract
Activation of the telomere maintenance mechanism is a key hallmark of cancer. Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of telomerase, which is highly expressed in more than 80% of tumors, including hepatocellular carcinoma (HCC). However, the exact mechanisms by which hTERT is up-regulated in HCCs and promotes tumor growth and progression is not fully understood. The aim of this study was to discover the novel molecular targets that modulate hTERT signaling and HCC growth. In this study, we pulled down and identified RBFOX3 (RNA binding protein fox-1 homolog 3) as a novel hTERT promoter-binding protein in HCC cells using biotin-streptavidin-agarose pull-down and proteomics approach, and validated it as a regulatory factor for hTERT signaling and tumor growth in HCCs. Knockdown of RBFOX3 suppressed the promoter activity and expression of hTERT and consequently inhibited the growth and progression of HCC cells in vitro and in vivo. The suppression of HCC growth mediated by RBFOX3 knockdown could be rescued by hTERT overexpression. Conversely, exogenous overexpression of RBFOX3 activated the promoter activity and expression of hTERT and promoted the growth and progression of HCC cells. Moreover, we found that RBFOX3 interacted with AP-2β to regulate the expression of hTERT. Furthermore, we demonstrated that RBFOX3 expression was higher in the tumor tissues of HCC patients compared to the corresponding paracancer tissues, and was positively correlated with hTERT expression. Kaplan-Meier analysis showed that the HCC patients with high levels of RBFOX3 and hTERT had poor prognosis. Collectively, our data indicate that RBFOX3 promotes HCC growth and progression and predicts a poor prognosis by activating the hTERT signaling, and suggest that the RBFOX3/hTERT pathway may be a potential therapeutic target for HCC patients.
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Protein 4.1R Exon 16 3' Splice Site Activation Requires Coordination among TIA1, Pcbp1, and RBM39 during Terminal Erythropoiesis. Mol Cell Biol 2017; 37:MCB.00446-16. [PMID: 28193846 DOI: 10.1128/mcb.00446-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 02/03/2017] [Indexed: 12/18/2022] Open
Abstract
Exon 16 of protein 4.1R encodes a spectrin/actin-binding peptide critical for erythrocyte membrane stability. Its expression during erythroid differentiation is regulated by alternative pre-mRNA splicing. A UUUUCCCCCC motif situated between the branch point and the 3' splice site is crucial for inclusion. We show that the UUUU region and the last three C residues in this motif are necessary for the binding of splicing factors TIA1 and Pcbp1 and that these proteins appear to act in a collaborative manner to enhance exon 16 inclusion. This element also activates an internal exon when placed in a corresponding intronic position in a heterologous reporter. The impact of these two factors is further enhanced by high levels of RBM39, whose expression rises during erythroid differentiation as exon 16 inclusion increases. TIA1 and Pcbp1 associate in a complex containing RBM39, which interacts with U2AF65 and SF3b155 and promotes U2 snRNP recruitment to the branch point. Our results provide a mechanism for exon 16 3' splice site activation in which a coordinated effort among TIA1, Pcbp1, and RBM39 stabilizes or increases U2 snRNP recruitment, enhances spliceosome A complex formation, and facilitates exon definition through RBM39-mediated splicing regulation.
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RBFOX3 regulates Claudin-1 expression in human lung tissue via attenuation of proteasomal degradation. Biosci Rep 2017; 37:BSR20160623. [PMID: 28126724 PMCID: PMC5322747 DOI: 10.1042/bsr20160623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/21/2017] [Accepted: 01/26/2017] [Indexed: 01/30/2023] Open
Abstract
RBFOX3, a nuclear RNA-binding protein, is well known as a regulator of alternative pre-mRNA splicing during neuronal development. However, other functions of RBFOX3 are poorly understood. Here, we investigated the function of RBFOX3 in the cytoplasm with respect to regulation of Claudin-1 expression. In human lung tissue, Claudin-1 is higher in RBFOX3-positive cells than in RBFOX3-negative cells. Immunostaining and mRNA quantification revealed that protein levels, but not mRNA levels, of Claudin-1 are increased by RBFOX3. In addition, cycloheximide treatment of human lung cancer cells revealed that RBFOX3 increases the stability of Claudin-1 through attenuation of its ubiquitination. Our study provides insights into the molecular mechanisms by which RBFOX3 regulates Claudin-1 expression in human lung tissue.
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Damianov A, Ying Y, Lin CH, Lee JA, Tran D, Vashisht AA, Bahrami-Samani E, Xing Y, Martin KC, Wohlschlegel JA, Black DL. Rbfox Proteins Regulate Splicing as Part of a Large Multiprotein Complex LASR. Cell 2016; 165:606-19. [PMID: 27104978 DOI: 10.1016/j.cell.2016.03.040] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 12/18/2015] [Accepted: 03/22/2016] [Indexed: 12/11/2022]
Abstract
Rbfox proteins control alternative splicing and posttranscriptional regulation in mammalian brain and are implicated in neurological disease. These proteins recognize the RNA sequence (U)GCAUG, but their structures and diverse roles imply a variety of protein-protein interactions. We find that nuclear Rbfox proteins are bound within a large assembly of splicing regulators (LASR), a multimeric complex containing the proteins hnRNP M, hnRNP H, hnRNP C, Matrin3, NF110/NFAR-2, NF45, and DDX5, all approximately equimolar to Rbfox. We show that splicing repression mediated by hnRNP M is stimulated by Rbfox. Virtually all the intron-bound Rbfox is associated with LASR, and hnRNP M motifs are enriched adjacent to Rbfox crosslinking sites in vivo. These findings demonstrate that Rbfox proteins bind RNA with a defined set of cofactors and affect a broader set of exons than previously recognized. The function of this multimeric LASR complex has implications for deciphering the regulatory codes controlling splicing networks.
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Affiliation(s)
- Andrey Damianov
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yi Ying
- Molecular Biology Interdepartmental Ph.D. Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Chia-Ho Lin
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ji-Ann Lee
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Diana Tran
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ajay A Vashisht
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Emad Bahrami-Samani
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yi Xing
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kelsey C Martin
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - James A Wohlschlegel
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Douglas L Black
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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Conboy JG. Developmental regulation of RNA processing by Rbfox proteins. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 8. [PMID: 27748060 DOI: 10.1002/wrna.1398] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 08/17/2016] [Accepted: 08/27/2016] [Indexed: 12/15/2022]
Abstract
The Rbfox genes encode an ancient family of sequence-specific RNA binding proteins (RBPs) that are critical developmental regulators in multiple tissues including skeletal muscle, cardiac muscle, and brain. The hallmark of Rbfox proteins is a single high-affinity RRM domain, highly conserved from insects to humans, that binds preferentially to UGCAUG motifs at diverse regulatory sites in pre-mRNA introns, mRNA 3'UTRs, and pre-miRNAs hairpin structures. Versatile regulatory circuits operate on Rbfox pre-mRNA and mRNA to ensure proper expression of Rbfox1 protein isoforms, which then act on the broader transcriptome to regulate alternative splicing networks, mRNA stability and translation, and microRNA processing. Complex Rbfox expression is encoded in large genes encompassing multiple promoters and alternative splicing options that govern spatiotemporal expression of structurally distinct and tissue-specific protein isoforms with different classes of RNA targets. Nuclear Rbfox1 is a candidate master regulator that binds intronic UGCAUG elements to impact splicing efficiency of target alternative exons, many in transcripts for other splicing regulators. Tissue-specificity of Rbfox-mediated alternative splicing is executed by combinatorial regulation through the integrated activity of Rbfox proteins and synergistic or antagonistic splicing factors. Studies in animal models show that Rbfox1-related genes are critical for diverse developmental processes including germ cell differentiation and memory in Drosophila, neuronal migration and function in mouse brain, myoblast fusion and skeletal muscle function, and normal heart function. Finally, genetic and biochemical evidence suggest that aberrations in Rbfox-regulated circuitry are risk factors for multiple human disorders, especially neurodevelopmental disorders including epilepsy and autism, and cardiac hypertrophy. WIREs RNA 2017, 8:e1398. doi: 10.1002/wrna.1398 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- John G Conboy
- Biological Systems and Engineering Division Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA
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Kim YE, Kim JO, Park KS, Won M, Kim KE, Kim KK. Transforming Growth Factor-β-Induced RBFOX3 Inhibition Promotes Epithelial-Mesenchymal Transition of Lung Cancer Cells. Mol Cells 2016; 39:625-30. [PMID: 27432190 PMCID: PMC4990755 DOI: 10.14348/molcells.2016.0150] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/06/2016] [Accepted: 07/07/2016] [Indexed: 01/05/2023] Open
Abstract
The RNA-binding protein Rbfox3 is a well-known splicing regulator that is used as a marker for post-mitotic neurons in various vertebrate species. Although recent studies indicate a variable expression of Rbfox3 in non-neuronal tissues, including lung tissue, its cellular function in lung cancer remains largely unknown. Here, we report that the number of RBFOX3-positive cells in tumorous lung tissue is lower than that in normal lung tissue. As the transforming growth factor-β (TGF-β) signaling pathway is important in cancer progression, we investigated its role in RBFOX3 expression in A549 lung adenocarcinoma cells. TGF-β1 treatment inhibited RBFOX3 expression at the transcriptional level. Further, RBFOX3 depletion led to a change in the expression levels of a subset of proteins related to epithelial-mesenchymal transition (EMT), such as E-cadherin and Claudin-1, during TGF-β1-induced EMT. In immunofluorescence microscopic analysis, mesenchymal morphology was more prominent in RBFOX3-depleted cells than in control cells. These findings show that TGF-β-induced RBFOX3 inhibition plays an important role in EMT and propose a novel role for RBFOX3 in cancer progression.
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Affiliation(s)
- Yong-Eun Kim
- Department of Biochemistry, Chungnam National University, Daejeon 34134,
Korea
| | - Jong Ok Kim
- Department of Pathology, Daejeon Saint Mary’s Hospital, The Catholic University of Korea, Daejeon 34943
Korea
| | - Ki-Sun Park
- Department of Biochemistry, Chungnam National University, Daejeon 34134,
Korea
| | - Minho Won
- Department of Pharmacology, College of Medicine, Chungnam National University, Daejeon 35015,
Korea
| | - Kyoon Eon Kim
- Department of Biochemistry, Chungnam National University, Daejeon 34134,
Korea
| | - Kee K. Kim
- Department of Biochemistry, Chungnam National University, Daejeon 34134,
Korea
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CD4 and CD8 T cells mediate distinct lethal meningoencephalitis in mice challenged with Tacaribe arenavirus. Cell Mol Immunol 2016; 14:90-107. [PMID: 27569560 PMCID: PMC5214944 DOI: 10.1038/cmi.2016.41] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 06/15/2016] [Accepted: 06/17/2016] [Indexed: 01/25/2023] Open
Abstract
Neonates are at increased risk of viral encephalopathies that can result in neurological dysfunction, seizures, permanent disability and even death. The neurological damage results from the combined effect of the virus and the immune response it elicits, thus finding tools to facilitate viral clearance from central nervous system (CNS) while minimizing neuron damage remains a critical challenge. Neonatal mice inoculated intraperitoneally with Tacaribe virus (TCRV) develop seizures, hindlimb paralysis and death within 15 days of inoculation. TCRV localizes to the CNS within days of challenge, primarily infecting astrocytes in the cerebellum and brain stem. We show that infection leads to inflammation, T cell and monocyte infiltration into the cerebellar parenchyma, apoptosis of astrocytes, neuronal degeneration and loss of Purkinje cells. Infiltrating antigen-specific T cells fail to clear the virus but drive the disease, as T-cell-deficient CD3ɛ KO mice survive TCRV infection with minimal inflammation or clinical manifestations despite no difference in CNS viral loads in comparison with T-cell sufficient mice. CD8+ T cells drive the pathology, which even in the absence of CD4+ T-cell help, infiltrate the parenchyma and mediate the apoptotic loss of cerebellar astrocytes, neurodegeneration and loss of Purkinje cells resulting in loss of balance, paralysis and death. CD4+ T cells are also pathogenic inducing gliosis and inflammation in the cerebellum and cerebrum that are associated with wasting and death several weeks after CD4+ T-cell transfer. These data demonstrate distinct pathogenic effects of CD4+ and CD8+ T cells and identify them as possible therapeutic targets.
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Hamada N, Ito H, Nishijo T, Iwamoto I, Morishita R, Tabata H, Momiyama T, Nagata KI. Essential role of the nuclear isoform of RBFOX1, a candidate gene for autism spectrum disorders, in the brain development. Sci Rep 2016; 6:30805. [PMID: 27481563 PMCID: PMC4969621 DOI: 10.1038/srep30805] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 07/07/2016] [Indexed: 01/10/2023] Open
Abstract
Gene abnormalities in RBFOX1, encoding an mRNA-splicing factor, have been shown to cause autism spectrum disorder and other neurodevelopmental disorders. Since pathophysiological significance of the dominant nuclear isoform in neurons, RBFOX1-isoform1 (iso1), remains to be elucidated, we performed comprehensive analyses of Rbfox1-iso1 during mouse corticogenesis. Knockdown of Rbfox1-iso1 by in utero electroporation caused abnormal neuronal positioning during corticogenesis, which was attributed to impaired migration. The defects were found to occur during radial migration and terminal translocation, perhaps due to impaired nucleokinesis. Axon extension and dendritic arborization were also suppressed in vivo in Rbfox1-iso1-deficient cortical neurons. In addition, electrophysiology experiments revealed significant defects in the membrane and synaptic properties of the deficient neurons. Aberrant morphology was further confirmed by in vitro analyses; Rbfox1-iso1-konckdown in hippocampal neurons resulted in the reduction of primary axon length, total length of dendrites, spine density and mature spine number. Taken together, this study shows that Rbfox1-iso1 plays an important role in neuronal migration and synapse network formation during corticogenesis. Defects in these critical processes may induce structural and functional defects in cortical neurons, and consequently contribute to the pathophysiology of neurodevelopmental disorders with RBFOX1 abnormalities.
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Affiliation(s)
- Nanako Hamada
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan.,Japan Society for the Promotion of Science, Tokyo, Japan
| | - Hidenori Ito
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan
| | - Takuma Nishijo
- Department of Pharmacology, Jikei University School of Medicine, Tokyo, Japan
| | - Ikuko Iwamoto
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan
| | - Rika Morishita
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan
| | - Hidenori Tabata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan
| | - Toshihiko Momiyama
- Department of Pharmacology, Jikei University School of Medicine, Tokyo, Japan
| | - Koh-Ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan.,Department of Neurochemistry, Nagoya University Graduate School of Medicine, Nagoya, Japan
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Mao S, Xiong G, Zhang L, Dong H, Liu B, Cohen NA, Cohen AS. Verification of the Cross Immunoreactivity of A60, a Mouse Monoclonal Antibody against Neuronal Nuclear Protein. Front Neuroanat 2016; 10:54. [PMID: 27242450 PMCID: PMC4865646 DOI: 10.3389/fnana.2016.00054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/02/2016] [Indexed: 11/13/2022] Open
Abstract
A60, the mouse monoclonal antibody against the neuronal nuclear protein (NeuN), is the most widely used neuronal marker in neuroscience research and neuropathological assays. Previous studies identified fragments of A60-immunoprecipitated protein as Synapsin I (Syn I), suggesting the antibody will demonstrate cross immunoreactivity. However, the likelihood of cross reactivity has never been verified by immunohistochemical techniques. Using our established tissue processing and immunofluorescent staining protocols, we found that A60 consistently labeled mossy fiber terminals in hippocampal area CA3. These A60-positive mossy fiber terminals could also be labeled by Syn I antibody. After treating brain slices with saponin in order to better preserve various membrane and/or vesicular proteins for immunostaining, we observed that A60 could also label additional synapses in various brain areas. Therefore, we used A60 together with a rabbit monoclonal NeuN antibody to confirm the existence of this cross reactivity. We showed that the putative band positive for A60 and Syn I could not be detected by the rabbit anti-NeuN in Western blotting. As efficient as Millipore A60 to recognize neuronal nuclei, the rabbit NeuN antibody demonstrated no labeling of synaptic structures in immunofluorescent staining. The present study successfully verified the cross reactivity present in immunohistochemistry, cautioning that A60 may not be the ideal biomarker to verify neuronal identity due to its cross immunoreactivity. In contrast, the rabbit monoclonal NeuN antibody used in this study may be a better candidate to substitute for A60.
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Affiliation(s)
- Shanping Mao
- Department of Neurology, Renmin Hospital, Wuhan University Wuhan, China
| | - Guoxiang Xiong
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, University of Pennslyvania Philadelphia, PA, USA
| | - Lei Zhang
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, University of Pennslyvania Philadelphia, PA, USA
| | - Huimin Dong
- Department of Neurology, Renmin Hospital, Wuhan University Wuhan, China
| | - Baohui Liu
- Department of Neurology, Renmin Hospital, Wuhan University Wuhan, China
| | - Noam A Cohen
- Philadelphia Veterans Affairs Medical Center, University of PennslyvaniaPhiladelphia, PA, USA; Departments of Otorhinolaryngology-Head and Neck Surgery, University of PennslyvaniaPhiladelphia, PA, USA
| | - Akiva S Cohen
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, University of PennslyvaniaPhiladelphia, PA, USA; Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine, University of PennslyvaniaPhiladelphia, PA, USA
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RBFOX1 and RBFOX2 are dispensable in iPSCs and iPSC-derived neurons and do not contribute to neural-specific paternal UBE3A silencing. Sci Rep 2016; 6:25368. [PMID: 27146458 PMCID: PMC4857170 DOI: 10.1038/srep25368] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 04/15/2016] [Indexed: 01/01/2023] Open
Abstract
Angelman Syndrome (AS) is a rare neurodevelopmental disorder caused by loss of function of the maternally inherited copy of UBE3A, an imprinted gene expressed biallelically in most tissues, but expressed exclusively from the maternal allele in neurons. Active transcription of the neuron-specific long non-coding RNA (lncRNA), UBE3A-ATS, has been shown to silence paternal UBE3A. We hypothesized that alternative splicing factors RBFOX2 and RBFOX1 might mediate splicing changes and result in the transcription of UBE3A-ATS in neurons. We found that RBFOX2 and RBFOX1 both bind to UBE3A-ATS transcript in neurons, but are not required for gene expression and/or neuron-specific processing in the SNURF/SNRPN-UBE3A region. However, we found that depletion of RBFOX2 causes a proliferation phenotype in immature neural cultures, suggesting that RBFOX2 is involved in division versus differentiation decisions in iPSC-derived neural progenitors. Absence of RBFOX2 also altered the expression of some genes that are important for glutamatergic neocortical development and Wnt-Frizzled signalling in mature neuronal cultures. Our data show that while RBFOX1 and RBFOX2 do not mediate neuron-specific processing of UBE3A-ATS, these proteins play important roles in developing neurons and are not completely functionally redundant.
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Towards understanding pre-mRNA splicing mechanisms and the role of SR proteins. Gene 2016; 587:107-19. [PMID: 27154819 DOI: 10.1016/j.gene.2016.04.057] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 04/30/2016] [Indexed: 01/04/2023]
Abstract
Alternative pre-mRNA splicing provides a source of vast protein diversity by removing non-coding sequences (introns) and accurately linking different exonic regions in the correct reading frame. The regulation of alternative splicing is essential for various cellular functions in both pathological and physiological conditions. In eukaryotic cells, this process is commonly used to increase proteomic diversity and to control gene expression either co- or post-transcriptionally. Alternative splicing occurs within a megadalton-sized, multi-component machine consisting of RNA and proteins; during the splicing process, this complex undergoes dynamic changes via RNA-RNA, protein-protein and RNA-protein interactions. Co-transcriptional splicing functionally integrates the transcriptional machinery, thereby enabling the two processes to influence one another, whereas post-transcriptional splicing facilitates the coupling of RNA splicing with post-splicing events. This review addresses the structural aspects of spliceosomes and the mechanistic implications of their stepwise assembly on the regulation of pre-mRNA splicing. Moreover, the role of phosphorylation-based, signal-induced changes in the regulation of the splicing process is demonstrated.
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Knott GJ, Bond CS, Fox AH. The DBHS proteins SFPQ, NONO and PSPC1: a multipurpose molecular scaffold. Nucleic Acids Res 2016; 44:3989-4004. [PMID: 27084935 PMCID: PMC4872119 DOI: 10.1093/nar/gkw271] [Citation(s) in RCA: 187] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/05/2016] [Indexed: 12/23/2022] Open
Abstract
Nuclear proteins are often given a concise title that captures their function, such as 'transcription factor,' 'polymerase' or 'nuclear-receptor.' However, for members of the Drosophila behavior/human splicing (DBHS) protein family, no such clean-cut title exists. DBHS proteins are frequently identified engaging in almost every step of gene regulation, including but not limited to, transcriptional regulation, RNA processing and transport, and DNA repair. Herein, we present a coherent picture of DBHS proteins, integrating recent structural insights on dimerization, nucleic acid binding modalities and oligomerization propensity with biological function. The emerging paradigm describes a family of dynamic proteins mediating a wide range of protein-protein and protein-nucleic acid interactions, on the whole acting as a multipurpose molecular scaffold. Overall, significant steps toward appreciating the role of DBHS proteins have been made, but we are only beginning to understand the complexity and broader importance of this family in cellular biology.
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Affiliation(s)
- Gavin J Knott
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, WA 6009, Australia
| | - Charles S Bond
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, WA 6009, Australia
| | - Archa H Fox
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, WA 6009, Australia Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, WA 6009, Australia
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Alekseeva OS, Gusel’nikova VV, Beznin GV, Korzhevskii DE. Prospects for the application of neun nuclear protein as a marker of the functional state of nerve cells in vertebrates. J EVOL BIOCHEM PHYS+ 2015. [DOI: 10.1134/s0022093015050014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Mircsof D, Langouët M, Rio M, Moutton S, Siquier-Pernet K, Bole-Feysot C, Cagnard N, Nitschke P, Gaspar L, Žnidarič M, Alibeu O, Fritz AK, Wolfer DP, Schröter A, Bosshard G, Rudin M, Koester C, Crestani F, Seebeck P, Boddaert N, Prescott K, Hines R, Moss SJ, Fritschy JM, Munnich A, Amiel J, Brown SA, Tyagarajan SK, Colleaux L. Mutations in NONO lead to syndromic intellectual disability and inhibitory synaptic defects. Nat Neurosci 2015; 18:1731-6. [PMID: 26571461 PMCID: PMC5392243 DOI: 10.1038/nn.4169] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/15/2015] [Indexed: 12/14/2022]
Abstract
The NONO protein has been characterized as an important transcriptional regulator in diverse cellular contexts. Here we show that loss of NONO function is a likely cause of human intellectual disability and that NONO-deficient mice have cognitive and affective deficits. Correspondingly, we find specific defects at inhibitory synapses, where NONO regulates synaptic transcription and gephyrin scaffold structure. Our data identify NONO as a possible neurodevelopmental disease gene and highlight the key role of the DBHS protein family in functional organization of GABAergic synapses.
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Affiliation(s)
- Dennis Mircsof
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland.,Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Maéva Langouët
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Marlène Rio
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Sébastien Moutton
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Karine Siquier-Pernet
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Christine Bole-Feysot
- Genomic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Nicolas Cagnard
- Bioinformatic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Patrick Nitschke
- Bioinformatic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Ludmila Gaspar
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Matej Žnidarič
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Olivier Alibeu
- Genomic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Ann-Kristina Fritz
- Institute of Anatomy, University of Zürich and Institute of Human Movement Sciences and Sport, ETH Zürich, Switzerland
| | - David P Wolfer
- Institute of Anatomy, University of Zürich and Institute of Human Movement Sciences and Sport, ETH Zürich, Switzerland
| | - Aileen Schröter
- Molecular Imaging and Functional Pharmacology Group, University of Zürich, Zürich, Switzerland
| | - Giovanna Bosshard
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Markus Rudin
- Molecular Imaging and Functional Pharmacology Group, University of Zürich, Zürich, Switzerland
| | - Christina Koester
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Florence Crestani
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Petra Seebeck
- Center for Integrative Rodent Physiology, University of Zürich, Zürich, Switzerland
| | - Nathalie Boddaert
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de radiologie pédiatrique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Katrina Prescott
- Yorkshire Regional Genetics Service, Leeds Teaching Hospitals National Health Service Trust, Department of Clinical Genetics, Chapel Allerton Hospital, Chapeltown Road, Leeds, UK
| | | | - Rochelle Hines
- Tufts University, Sackler School of Graduate Biomedical Sciences, Boston, Massachusetts, USA
| | - Steven J Moss
- Tufts University, Sackler School of Graduate Biomedical Sciences, Boston, Massachusetts, USA
| | - Jean-Marc Fritschy
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Arnold Munnich
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Jeanne Amiel
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Steven A Brown
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Shiva K Tyagarajan
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Laurence Colleaux
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
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Knott GJ, Lee M, Passon DM, Fox AH, Bond CS. Caenorhabditis elegans NONO-1: Insights into DBHS protein structure, architecture, and function. Protein Sci 2015; 24:2033-43. [PMID: 26435036 DOI: 10.1002/pro.2816] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 09/24/2015] [Indexed: 12/14/2022]
Abstract
Members of the Drosophila behavior/human splicing (DBHS) protein family have been characterized in the vertebrates Homo sapiens and Mus musculus, and the invertebrates Drosophila melanogaster and Chironomus tentans. Collectively, both vertebrate and invertebrate DBHS proteins function throughout gene regulation, largely but not always, within the nucleus. In this study, we report a structural and bioinformatic analysis of the DBHS protein family to guide future studies into DBHS protein function. To explore the structural plasticity of the family, we describe the 2.4 Å crystal structure of Caenorhabditis elegans non-POU domain-containing octamer-binding protein 1 (NONO-1). The structure is dimeric, with a domain arrangement consistent with mammalian DBHS proteins. Comparison with the DBHS structures available from H. sapiens reveals that there is inherent domain flexibility within the homologous DBHS region. Mapping amino acid similarity within the family to the NONO-1 dimer highlights the dimer interface, coiled-coil oligomerization motif, and putative RNA binding surfaces. Surprisingly, the interior surface of RNA recognition motif 2 (RRM2) that faces a large internal void is highly variable, but the external β2-β3 loops of RRM2 show remarkable preservation. Overall, the DBHS region is under strong purifying selection, whereas the sequences N- and C-terminal to the DBHS region are less constrained. The findings described in this study provide a molecular basis for further investigation into the mechanistic function of the DBHS protein family in biology.
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Affiliation(s)
- Gavin J Knott
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - Mihwa Lee
- Department of Biochemistry and Genetics, La Trobe University, Melbourne, Victoria, Australia
| | - Daniel M Passon
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, 6009, Australia.,European Molecular Biology Laboratories, Hamburg, 22761, Germany
| | - Archa H Fox
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - Charles S Bond
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, 6009, Australia
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Hamada N, Ito H, Iwamoto I, Morishita R, Tabata H, Nagata KI. Role of the cytoplasmic isoform of RBFOX1/A2BP1 in establishing the architecture of the developing cerebral cortex. Mol Autism 2015; 6:56. [PMID: 26500751 PMCID: PMC4617638 DOI: 10.1186/s13229-015-0049-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 10/10/2015] [Indexed: 11/29/2022] Open
Abstract
Background RBFOX1 (also known as FOX1 or A2BP1) regulates alternative splicing of a variety of transcripts crucial for neuronal functions. Physiological significance of RBFOX1 during brain development is seemingly essential since abnormalities in the gene cause autism spectrum disorder (ASD) and other neurodevelopmental and neuropsychiatric disorders such as intellectual disability, epilepsy, attention deficit hyperactivity disorder, and schizophrenia. RBFOX1 was also shown to serve as a “hub” in ASD gene transcriptome network. However, the pathophysiological significance of RBFOX1 gene abnormalities remains to be clarified. Methods To elucidate the pathophysiological relevance of Rbfox1, we performed a battery of in vivo and in vitro analyses of the brain-specific cytoplasmic isoform, Rbfox1-iso2, during mouse corticogenesis. In vivo analyses were based on in utero electroporation, and the role of Rbfox1-iso2 in cortical neuron migration, neurogenesis, and morphology was investigated by morphological methods including confocal laser microscope-assisted time-lapse imaging. In vitro analyses were carried out to examine the morphology of primary cultured mouse hippocampal neurons. Results Silencing of Rbfox1-iso2 in utero caused defects in the radial migration and terminal translocation of cortical neurons during corticogenesis. Time-lapse imaging revealed that radial migration was apparently impaired by dysregulated nucleokinesis. Rbfox1-iso2 also regulated neuronal network formation in vivo since axon extension to the opposite hemisphere and dendritic arborization were hampered by the knockdown. In in vitro analyses, spine density and mature spine number were reduced in Rbfox1-iso2-deficient hippocampal neurons. Conclusions Impaired Rbfox1-iso2 function was found to cause abnormal corticogenesis during brain development. The abnormal process may underlie the basic pathophysiology of ASD and other neurodevelopmental disorders and may contribute to the emergence of the clinical symptoms of the patients with RBFOX1 gene abnormalities. Electronic supplementary material The online version of this article (doi:10.1186/s13229-015-0049-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nanako Hamada
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
| | - Hidenori Ito
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
| | - Ikuko Iwamoto
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
| | - Rika Morishita
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
| | - Hidenori Tabata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
| | - Koh-Ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai Aichi, 480-0392 Japan
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45
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Cytoarchitecture and neurocytology of rabbit cingulate cortex. Brain Struct Funct 2015; 221:3571-89. [DOI: 10.1007/s00429-015-1120-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 09/23/2015] [Indexed: 12/20/2022]
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46
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Wang G, Yang H, Yan S, Wang CE, Liu X, Zhao B, Ouyang Z, Yin P, Liu Z, Zhao Y, Liu T, Fan N, Guo L, Li S, Li XJ, Lai L. Cytoplasmic mislocalization of RNA splicing factors and aberrant neuronal gene splicing in TDP-43 transgenic pig brain. Mol Neurodegener 2015; 10:42. [PMID: 26334913 PMCID: PMC4557629 DOI: 10.1186/s13024-015-0036-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Accepted: 08/10/2015] [Indexed: 12/13/2022] Open
Abstract
Background TAR DNA-binding protein 43 (TDP-43) is a nuclear protein, but it is redistributed in the neuronal cytoplasm in both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Because small transgenic animal models often lack cytoplasmic TDP-43, how the cytoplasmic accumulation of TDP-43 contributes to these diseases remains unclear. The current study is aimed at studying the mechanism of cytoplasmic pathology of TDP-43. Results We established transgenic pigs expressing mutant TDP-43 (M337V). This pig model shows severe phenotypes and early death. We found that transgenic TDP-43 is also distributed in the cytoplasm of neuronal cells in the spinal cord and brain. Transgenic TDP-43 interacts with PSF, an RNA splicing factor that associates with NeuN to regulate neuronal RNA splicing. The interaction of TDP-43, PSF and NeuN causes PSF and NeuN mislocalize into the neuronal cytoplasm in transgenic pigs. Consistently, abnormal PSF-related neuronal RNA splicing is seen in TDP-43 transgenic pigs. The cytoplasmic localization of PSF and NeuN as well as abnormal PSF-related neuronal RNA splicing was also found in ALS patient brains. Conclusion Our findings from a large mammalian model suggest that cytoplasmic mutant TDP-43 could reduce the nuclear function of RNA splicing factors, contributing to neuropathology.
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Affiliation(s)
- Guohao Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Huaqiang Yang
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Sen Yan
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Chuan-En Wang
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Xudong Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Bentian Zhao
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Zhen Ouyang
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Peng Yin
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Zhaoming Liu
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Yu Zhao
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Tao Liu
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Nana Fan
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Lin Guo
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Shihua Li
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Xiao-Jiang Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Liangxue Lai
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
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Yarosh CA, Iacona JR, Lutz CS, Lynch KW. PSF: nuclear busy-body or nuclear facilitator? WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 6:351-67. [PMID: 25832716 PMCID: PMC4478221 DOI: 10.1002/wrna.1280] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 01/25/2023]
Abstract
PTB-associated splicing factor (PSF) is an abundant and essential nucleic acid-binding protein that participates in a wide range of gene regulatory processes and cellular response pathways. At the protein level, PSF consists of multiple domains, many of which remain poorly characterized. Although grouped in a family with the proteins p54nrb/NONO and PSPC1 based on sequence homology, PSF contains additional protein sequence not included in other family members. Consistently, PSF has also been implicated in functions not ascribed to p54nrb/NONO or PSPC1. Here, we provide a review of the cellular activities in which PSF has been implicated and what is known regarding the mechanisms by which PSF functions in each case. We propose that the complex domain arrangement of PSF allows for its diversity of function and integration of activities. Finally, we discuss recent evidence that individual activities of PSF can be regulated independently from one another through the activity of domain-specific co-factors.
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Affiliation(s)
- Christopher A Yarosh
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph R Iacona
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers Biomedical and Health Sciences-New Jersey Medical School, Newark, NJ, USA
| | - Carol S Lutz
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers Biomedical and Health Sciences-New Jersey Medical School, Newark, NJ, USA
| | - Kristen W Lynch
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
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A Neuronal Activity-Dependent Dual Function Chromatin-Modifying Complex Regulates Arc Expression. eNeuro 2015; 2:eN-NWR-0020-14. [PMID: 26464965 PMCID: PMC4586916 DOI: 10.1523/eneuro.0020-14.2015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 01/18/2015] [Accepted: 01/22/2015] [Indexed: 11/21/2022] Open
Abstract
Chromatin modification is an important epigenetic mechanism underlying neuroplasticity. Histone methylation and acetylation have both been shown to modulate gene expression, but the machinery responsible for mediating these changes in neurons has remained elusive. Here we identify a chromatin-modifying complex containing the histone demethylase PHF8 and the acetyltransferase TIP60 as a key regulator of the activity-induced expression of Arc, an important mediator of synaptic plasticity. Clinically, mutations in PHF8 cause X-linked mental retardation while TIP60 has been implicated in the pathogenesis of Alzheimer's disease. Within minutes of increased synaptic activity, this dual function complex is rapidly recruited to the Arc promoter, where it specifically counteracts the transcriptionally repressive histone mark H3K9me2 to facilitate the formation of the transcriptionally permissive H3K9acS10P, thereby favoring transcriptional activation. Consequently, gain-of-function of the PHF8-TIP60 complex in primary rat hippocampal neurons has a positive effect on early activity-induced Arc gene expression, whereas interfering with the function of this complex abrogates it. A global proteomics screen revealed that the majority of common interactors of PHF8 and TIP60 were involved in mRNA processing, including PSF, an important molecule involved in neuronal gene regulation. Finally, we proceeded to show, using super-resolution microscopy, that PHF8 and TIP60 interact at the single molecule level with PSF, thereby situating this chromatin modifying complex at the crossroads of transcriptional activation. These findings point toward a mechanism by which an epigenetic pathway can regulate neuronal activity-dependent gene transcription, which has implications in the development of novel therapeutics for disorders of learning and memory.
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Duan W, Zhang YP, Hou Z, Huang C, Zhu H, Zhang CQ, Yin Q. Novel Insights into NeuN: from Neuronal Marker to Splicing Regulator. Mol Neurobiol 2015; 53:1637-1647. [PMID: 25680637 DOI: 10.1007/s12035-015-9122-5] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/01/2015] [Indexed: 01/07/2023]
Abstract
Neuronal nuclei (NeuN) is a well-recognized "marker" that is detected exclusively in post-mitotic neurons and was initially identified through an immunological screen to produce neuron-specific antibodies. Immunostaining evidence indicates that NeuN is distributed in the nuclei of mature neurons in nearly all parts of the vertebrate nervous system. NeuN is highly conserved among species and is stably expressed during specific stages of development. Therefore, NeuN has been considered to be a reliable marker of mature neurons for the past two decades. However, this role has been challenged by recent studies indicating that NeuN staining is variable and even absent during certain diseases and specific physiological states. More importantly, despite the widespread use of the anti-NeuN antibody, the natural identity of the NeuN protein remained elusive for 17 years. NeuN was recently eventually identified as an epitope of Rbfox3, which is a novel member of the Rbfox1 family of splicing factors. This identification might provide a novel perspective on NeuN expression during both physiological and pathological conditions. This review summarizes the current progress on the biochemical identity and biological significance of NeuN and recommends caution when applying NeuN immunoreactivity as a definitive marker of mature neurons in certain diseases and specific physiological states.
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Affiliation(s)
- Wei Duan
- Department of Neurology, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, People's Republic of China
| | - Yu-Ping Zhang
- Department of Pediatrics, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, People's Republic of China
| | - Zhi Hou
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, People's Republic of China
| | - Chen Huang
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA
| | - He Zhu
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA.,Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37232, USA.,Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA.,The Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, 37232, USA
| | - Chun-Qing Zhang
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, People's Republic of China.
| | - Qing Yin
- Department of Rehabilitation and Physical Therapy, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, People's Republic of China.
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Gusel’nikova VV, Korzhevskiy DE. NeuN As a Neuronal Nuclear Antigen and Neuron Differentiation Marker. Acta Naturae 2015; 7:42-7. [PMID: 26085943 PMCID: PMC4463411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The NeuN protein is localized in nuclei and perinuclear cytoplasm of most of the neurons in the central nervous system of mammals. Monoclonal antibodies to the NeuN protein have been actively used in the immunohistochemical research of neuronal differentiation to assess the functional state of neurons in norm and pathology for more than 20 years. Recently, NeuN antibodies have begun to be applied in the differential morphological diagnosis of cancer. However, the structure of the protein, which can be revealed by antibodies to NeuN, remained unknown until recently, and the functions of the protein are still not fully clear. In the present mini-review, data on NeuN accumulated so far are summarized and analyzed. Data on the structure and properties of the protein, its isoforms, intracellular localization, and hypothesized functions are reported. The application field of immunocytochemical detection of NeuN in scientific and clinical studies, as well as the difficulties in the interpretation of the obtained experimental data and their possible causes, is described in details.
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Affiliation(s)
- V. V. Gusel’nikova
- Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, akad. Pavlov str., 12, St. Petersburg, 197376, Russia
| | - D. E. Korzhevskiy
- Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, akad. Pavlov str., 12, St. Petersburg, 197376, Russia
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