1
|
Huang X, Cheng S, Han J. Polyglutamine binding protein 1 regulates neurite outgrowth through recruiting N-WASP. J Biol Chem 2024; 300:107537. [PMID: 38971314 PMCID: PMC11339035 DOI: 10.1016/j.jbc.2024.107537] [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: 05/14/2024] [Revised: 06/24/2024] [Accepted: 06/25/2024] [Indexed: 07/08/2024] Open
Abstract
Neurite outgrowth is a critical step in neural development, leading to the generation of neurite branches that allow individual neurons to make contacts with multiple neurons within the target region. Polyglutamine-binding protein 1 (PQBP1) is a highly conserved protein with a key role in neural development. Our recent mass spectrometric analysis showed that PQBP1 associates with neural Wiskott-Aldrich syndrome protein (N-WASP), an important actin polymerization-promoting factor involved in neurite outgrowth. Here, we report that the WW domain of PQBP1 directly interacts with the proline-rich domain of N-WASP. The disruption of this interaction leads to impaired neurite outgrowth and growth cone size. Furthermore, we demonstrate that PQBP1/N-WASP interaction is critical for the recruitment of N-WASP to the growth cone, but does not affect N-WASP protein levels or N-WASP-induced actin polymerization. Our results indicated that PQBP1 regulates neurite outgrowth by recruiting N-WASP to the growth cone, thus representing an alternative molecular mechanism via which PQBP1-mediates neurite outgrowth.
Collapse
Affiliation(s)
- Xuejiao Huang
- School of Life Science and Technology, The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China
| | - Shanshan Cheng
- School of Life Science and Technology, The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China.
| | - Junhai Han
- School of Life Science and Technology, The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, JS, China.
| |
Collapse
|
2
|
Corda PO, Bollen M, Ribeiro D, Fardilha M. Emerging roles of the Protein Phosphatase 1 (PP1) in the context of viral infections. Cell Commun Signal 2024; 22:65. [PMID: 38267954 PMCID: PMC10807198 DOI: 10.1186/s12964-023-01468-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/30/2023] [Indexed: 01/26/2024] Open
Abstract
Protein Phosphatase 1 (PP1) is a major serine/threonine phosphatase in eukaryotes, participating in several cellular processes and metabolic pathways. Due to their low substrate specificity, PP1's catalytic subunits do not exist as free entities but instead bind to Regulatory Interactors of Protein Phosphatase One (RIPPO), which regulate PP1's substrate specificity and subcellular localization. Most RIPPOs bind to PP1 through combinations of short linear motifs (4-12 residues), forming highly specific PP1 holoenzymes. These PP1-binding motifs may, hence, represent attractive targets for the development of specific drugs that interfere with a subset of PP1 holoenzymes. Several viruses exploit the host cell protein (de)phosphorylation machinery to ensure efficient virus particle formation and propagation. While the role of many host cell kinases in viral life cycles has been extensively studied, the targeting of phosphatases by viral proteins has been studied in less detail. Here, we compile and review what is known concerning the role of PP1 in the context of viral infections and discuss how it may constitute a putative host-based target for the development of novel antiviral strategies.
Collapse
Affiliation(s)
- Pedro O Corda
- Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Mathieu Bollen
- Department of Cellular and Molecular Medicine, Laboratory of Biosignaling & Therapeutics, Katholieke Universiteit Leuven, Louvain, Belgium
| | - Daniela Ribeiro
- Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, Aveiro, Portugal.
| | - Margarida Fardilha
- Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, Aveiro, Portugal.
| |
Collapse
|
3
|
Liu W, Xie H, Liu X, Xu S, Cheng S, Wang Z, Xie T, Zhang ZC, Han J. PQBP1 regulates striatum development through balancing striatal progenitor proliferation and differentiation. Cell Rep 2023; 42:112277. [PMID: 36943865 DOI: 10.1016/j.celrep.2023.112277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 01/16/2023] [Accepted: 03/03/2023] [Indexed: 03/23/2023] Open
Abstract
The balance between cell proliferation and differentiation is essential for maintaining the neural progenitor pool and brain development. Although the mechanisms underlying cell proliferation and differentiation at the transcriptional level have been studied intensively, post-transcriptional regulation of cell proliferation and differentiation remains largely unclear. Here, we show that deletion of the alternative splicing regulator PQBP1 in striatal progenitors results in defective striatal development due to impaired neurogenesis of spiny projection neurons (SPNs). Pqbp1-deficient striatal progenitors exhibit declined proliferation and increased differentiation, resulting in a reduced striatal progenitor pool. We further reveal that PQBP1 associates with components in splicing machinery. The alternative splicing profiles identify that PQBP1 promotes the exon 9 inclusion of Numb, a variant that mediates progenitor proliferation. These findings identify PQBP1 as a regulator in balancing striatal progenitor proliferation and differentiation and provide alternative insights into the pathogenic mechanisms underlying Renpenning syndrome.
Collapse
Affiliation(s)
- Wenhua Liu
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China
| | - Hao Xie
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China
| | - Xian Liu
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China
| | - Shoujing Xu
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China
| | - Shanshan Cheng
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China
| | - Zheng Wang
- School of Psychological and Cognitive Sciences, Beijing Key Laboratory of Behavior and Mental Health, IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Ting Xie
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Zi Chao Zhang
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
| | - Junhai Han
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China; Department of Neurology, Affiliated ZhongDa Hospital, Institute of Neuropsychiatry, Southeast University, Nanjing, Jiangsu 210009, China.
| |
Collapse
|
4
|
The role of PQBP1 in neural development and function. Biochem Soc Trans 2023; 51:363-372. [PMID: 36815699 DOI: 10.1042/bst20220920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 01/27/2023] [Accepted: 02/07/2023] [Indexed: 11/17/2022]
Abstract
Mutations in the polyglutamine tract-binding protein 1 (PQBP1) gene are associated with Renpenning syndrome, which is characterized by microcephaly, intellectual deficiency, short stature, small testes, and distinct facial dysmorphism. Studies using different models have revealed that PQBP1 plays essential roles in neural development and function. In this mini-review, we summarize recent findings relating to the roles of PQBP1 in these processes, including in the regulation of neural progenitor proliferation, neural projection, synaptic growth, neuronal survival, and cognitive function via mRNA transcription and splicing-dependent or -independent processes. The novel findings provide insights into the mechanisms underlying the pathogenesis of Renpenning syndrome and may advance drug discovery and treatment for this condition.
Collapse
|
5
|
Martin EMMA, Enriquez A, Sparrow DB, Humphreys DT, McInerney-Leo AM, Leo PJ, Duncan EL, Iyer KR, Greasby JA, Ip E, Giannoulatou E, Sheng D, Wohler E, Dimartino C, Amiel J, Capri Y, Lehalle D, Mory A, Wilnai Y, Lebenthal Y, Gharavi AG, Krzemień GG, Miklaszewska M, Steiner RD, Raggio C, Blank R, Baris Feldman H, Milo Rasouly H, Sobreira NLM, Jobling R, Gordon CT, Giampietro PF, Dunwoodie SL, Chapman G. Heterozygous loss of WBP11 function causes multiple congenital defects in humans and mice. Hum Mol Genet 2021; 29:3662-3678. [PMID: 33276377 DOI: 10.1093/hmg/ddaa258] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/09/2020] [Accepted: 11/25/2020] [Indexed: 12/31/2022] Open
Abstract
The genetic causes of multiple congenital anomalies are incompletely understood. Here, we report novel heterozygous predicted loss-of-function (LoF) and predicted damaging missense variants in the WW domain binding protein 11 (WBP11) gene in seven unrelated families with a variety of overlapping congenital malformations, including cardiac, vertebral, tracheo-esophageal, renal and limb defects. WBP11 encodes a component of the spliceosome with the ability to activate pre-messenger RNA splicing. We generated a Wbp11 null allele in mouse using CRISPR-Cas9 targeting. Wbp11 homozygous null embryos die prior to E8.5, indicating that Wbp11 is essential for development. Fewer Wbp11 heterozygous null mice are found than expected due to embryonic and postnatal death. Importantly, Wbp11 heterozygous null mice are small and exhibit defects in axial skeleton, kidneys and esophagus, similar to the affected individuals, supporting the role of WBP11 haploinsufficiency in the development of congenital malformations in humans. LoF WBP11 variants should be considered as a possible cause of VACTERL association as well as isolated Klippel-Feil syndrome, renal agenesis or esophageal atresia.
Collapse
Affiliation(s)
- Ella M M A Martin
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Annabelle Enriquez
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia
| | - Duncan B Sparrow
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Science, UNSW, Sydney 2052, Australia.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - David T Humphreys
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Molecular, Structural and Computational Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Aideen M McInerney-Leo
- Dermatology Research Centre, The University of Queensland Diamantina Institute, Translational Research Institute, Brisbane 4072, Australia
| | - Paul J Leo
- Translational Genomics Group, Institute of Health and Biomedical Innovation, Queensland University of Technology, Translational Research Institute, Princess Alexandra Hospital, Woolloongabba 4102, Australia
| | - Emma L Duncan
- Translational Genomics Group, Institute of Health and Biomedical Innovation, Queensland University of Technology, Translational Research Institute, Princess Alexandra Hospital, Woolloongabba 4102, Australia.,Department of Twin Research & Genetic Epidemiology, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, London SE1 7EH, UK.,Faculty of Medicine, University of Queensland, Herston 4006, Australia
| | - Kavitha R Iyer
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Joelene A Greasby
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Eddie Ip
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Computational Genomics Laboratory, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Eleni Giannoulatou
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Computational Genomics Laboratory, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Delicia Sheng
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University, Baltimore 21287, USA
| | - Clémantine Dimartino
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France
| | - Jeanne Amiel
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France.,Département de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris 75015, France
| | - Yline Capri
- Département de Génétique, Hôpital Robert Debré, Assistance Publique Hôpitaux de Paris, Paris 75019, France
| | - Daphné Lehalle
- Centre Hospitalier Intercommunal Créteil, Créteil 94000, France
| | - Adi Mory
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel
| | - Yael Wilnai
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel
| | - Yael Lebenthal
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.,Dana-Dwek Children's Hospital, Tel Aviv Sourasky Medical Center, Pediatric Endocrinology and Diabetes Unit, Tel Aviv 6423906, Israel
| | - Ali G Gharavi
- Department of Medicine, Division of Nephrology, Columbia University, New York, NY 10032, USA
| | - Grażyna G Krzemień
- Department of Pediatrics and Nephrology, Warsaw Medical University, Warsaw 02-091, Poland
| | - Monika Miklaszewska
- Department of Pediatric Nephrology and Hypertension, Jagiellonian University Medical College, Kraków 30-663, Poland
| | - Robert D Steiner
- Marshfield Clinic Health System, Marshfield, WI 54449, USA.,University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA
| | - Cathy Raggio
- Hospital for Special Surgery, Pediatrics Orthopedic Surgery, New York, NY 10021, USA
| | - Robert Blank
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Hagit Baris Feldman
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Hila Milo Rasouly
- Department of Medicine, Division of Nephrology, Columbia University, New York, NY 10032, USA
| | - Nara L M Sobreira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University, Baltimore 21287, USA
| | - Rebekah Jobling
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON M5G1X3, Canada
| | - Christopher T Gordon
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France
| | - Philip F Giampietro
- Department of Pediatrics, University of Illinois-Chicago, Chicago, IL 60607, USA
| | - Sally L Dunwoodie
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia.,Faculty of Science, UNSW, Sydney 2052, Australia
| | - Gavin Chapman
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia
| |
Collapse
|
6
|
The splicing factor XAB2 interacts with ERCC1-XPF and XPG for R-loop processing. Nat Commun 2021; 12:3153. [PMID: 34039990 PMCID: PMC8155215 DOI: 10.1038/s41467-021-23505-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 04/27/2021] [Indexed: 12/11/2022] Open
Abstract
RNA splicing, transcription and the DNA damage response are intriguingly linked in mammals but the underlying mechanisms remain poorly understood. Using an in vivo biotinylation tagging approach in mice, we show that the splicing factor XAB2 interacts with the core spliceosome and that it binds to spliceosomal U4 and U6 snRNAs and pre-mRNAs in developing livers. XAB2 depletion leads to aberrant intron retention, R-loop formation and DNA damage in cells. Studies in illudin S-treated cells and Csbm/m developing livers reveal that transcription-blocking DNA lesions trigger the release of XAB2 from all RNA targets tested. Immunoprecipitation studies reveal that XAB2 interacts with ERCC1-XPF and XPG endonucleases outside nucleotide excision repair and that the trimeric protein complex binds RNA:DNA hybrids under conditions that favor the formation of R-loops. Thus, XAB2 functionally links the spliceosomal response to DNA damage with R-loop processing with important ramifications for transcription-coupled DNA repair disorders. XPA-binding protein (XAB)-2 is the human homologue of the yeast pre-mRNA splicing factor Syf1. Here the authors use an in vivo biotinylation tagging approach to show XAB2’s role in DNA repair, RNA splicing and transcription during mammalian development.
Collapse
|
7
|
Pankivskyi S, Pastré D, Steiner E, Joshi V, Rynditch A, Hamon L. ITSN1 regulates SAM68 solubility through SH3 domain interactions with SAM68 proline-rich motifs. Cell Mol Life Sci 2020; 78:1745-1763. [PMID: 32780150 PMCID: PMC7904728 DOI: 10.1007/s00018-020-03610-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/03/2020] [Accepted: 07/22/2020] [Indexed: 02/06/2023]
Abstract
SAM68 is an mRNA-binding protein involved in mRNA processing in the nucleus that forms membraneless compartments called SAM68 Nuclear Bodies (SNBs). We found that intersectin 1 (ITSN1), a multidomain scaffold protein harboring five soluble SH3 domains, interacts with SAM68 proline-rich motifs (PRMs) surrounded by self-adhesive low complexity domains. While SAM68 is poorly soluble in vitro, the interaction of ITSN1 SH3 domains and mRNA with SAM68 enhances its solubility. In HeLa cells, the interaction between the first ITSN1 SH3 domain (SH3A) and P0, the N-terminal PRM of SAM68, induces the dissociation of SNBs. In addition, we reveal the ability of another SH3 domain (SH3D) of ITSN1 to bind to mRNAs. ITSN1 and mRNA may thus act in concert to promote SAM68 solubilization, consistent with the absence of mRNA in SNBs in cells. Together, these results support the notion of a specific chaperoning of PRM-rich SAM68 within nuclear ribonucleoprotein complexes by ITSN1 that may regulate the processing of a fraction of nuclear mRNAs, notably SAM68-controlled splicing events related to higher neuronal functions or cancer progression. This observation may also serve as a putative model of the interaction between other PRM-rich RBPs and signaling proteins harboring SH3 domains.
Collapse
Affiliation(s)
- S Pankivskyi
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France.,Institute of Molecular Biology and Genetics, The National Academy of Sciences, 150 Zabolotnogo Street, Kyiv, 03680, Ukraine
| | - D Pastré
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - E Steiner
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - V Joshi
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - A Rynditch
- Institute of Molecular Biology and Genetics, The National Academy of Sciences, 150 Zabolotnogo Street, Kyiv, 03680, Ukraine.
| | - L Hamon
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France.
| |
Collapse
|
8
|
Park EM, Scott PM, Clutario K, Cassidy KB, Zhan K, Gerber SA, Holland AJ. WBP11 is required for splicing the TUBGCP6 pre-mRNA to promote centriole duplication. J Cell Biol 2020; 219:133543. [PMID: 31874114 PMCID: PMC7039186 DOI: 10.1083/jcb.201904203] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 09/24/2019] [Accepted: 10/22/2019] [Indexed: 12/15/2022] Open
Abstract
Centriole duplication occurs once in each cell cycle to maintain centrosome number. A previous genome-wide screen revealed that depletion of 14 RNA splicing factors leads to a specific defect in centriole duplication, but the cause of this deficit remains unknown. Here, we identified an additional pre-mRNA splicing factor, WBP11, as a novel protein required for centriole duplication. Loss of WBP11 results in the retention of ∼200 introns, including multiple introns in TUBGCP6, a central component of the γ-TuRC. WBP11 depletion causes centriole duplication defects, in part by causing a rapid decline in the level of TUBGCP6. Several additional splicing factors that are required for centriole duplication interact with WBP11 and are required for TUBGCP6 expression. These findings provide insight into how the loss of a subset of splicing factors leads to a failure of centriole duplication. This may have clinical implications because mutations in some spliceosome proteins cause microcephaly and/or growth retardation, phenotypes that are strongly linked to centriole defects.
Collapse
Affiliation(s)
- Elizabeth M Park
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Phillip M Scott
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kevin Clutario
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Katelyn B Cassidy
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Kevin Zhan
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Scott A Gerber
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH.,Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH.,Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH
| | - Andrew J Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| |
Collapse
|
9
|
Liu X, Dou LX, Han J, Zhang ZC. The Renpenning syndrome-associated protein PQBP1 facilitates the nuclear import of splicing factor TXNL4A through the karyopherin β2 receptor. J Biol Chem 2020; 295:4093-4100. [PMID: 32041777 PMCID: PMC7105315 DOI: 10.1074/jbc.ra119.012214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/05/2020] [Indexed: 11/06/2022] Open
Abstract
Renpenning syndrome belongs to a group of X-linked intellectual disability disorders. The Renpenning syndrome-associated protein PQBP1 (polyglutamine-binding protein 1) is intrinsically disordered, associates with several splicing factors, and is involved in pre-mRNA splicing. PQBP1 uses its C-terminal YxxPxxVL motif for binding to the splicing factor TXNL4A (thioredoxin like 4A), but the biological function of this interaction has yet to be elucidated. In this study, using recombinant protein expression, in vitro binding assays, and immunofluorescence microscopy in HeLa cells, we found that a recently reported X-linked intellectual disability-associated missense mutation, resulting in the PQBP1-P244L variant, disrupts the interaction with TXNL4A. We further show that this interaction is critical for the subcellular location of TXNL4A. In combination with other PQBP1 variants lacking a functional nuclear localization signal required for recognition by the nuclear import receptor karyopherin β2, we demonstrate that PQBP1 facilitates the nuclear import of TXNL4A via a piggyback mechanism. These findings expand our understanding of the molecular basis of the PQBP1-TXNL4A interaction and of the etiology and pathogenesis of Renpenning syndrome and related disorders.
Collapse
Affiliation(s)
- Xian Liu
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu 210096, China
| | - Lin-Xia Dou
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu 210096, China
| | - Junhai Han
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Zi Chao Zhang
- School of Life Science and Technology, the Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China.
| |
Collapse
|
10
|
Nimeth BA, Riegler S, Kalyna M. Alternative Splicing and DNA Damage Response in Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:91. [PMID: 32140165 PMCID: PMC7042379 DOI: 10.3389/fpls.2020.00091] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 01/21/2020] [Indexed: 05/06/2023]
Abstract
Plants are exposed to a variety of abiotic and biotic stresses that may result in DNA damage. Endogenous processes - such as DNA replication, DNA recombination, respiration, or photosynthesis - are also a threat to DNA integrity. It is therefore essential to understand the strategies plants have developed for DNA damage detection, signaling, and repair. Alternative splicing (AS) is a key post-transcriptional process with a role in regulation of gene expression. Recent studies demonstrate that the majority of intron-containing genes in plants are alternatively spliced, highlighting the importance of AS in plant development and stress response. Not only does AS ensure a versatile proteome and influence the abundance and availability of proteins greatly, it has also emerged as an important player in the DNA damage response (DDR) in animals. Despite extensive studies of DDR carried out in plants, its regulation at the level of AS has not been comprehensively addressed. Here, we provide some insights into the interplay between AS and DDR in plants.
Collapse
|
11
|
Zhang Y, Zhao H, Xu W, Jiang D, Huang L, Li L. High Expression of PQBP1 and Low Expression of PCK2 are Associated with Metastasis and Recurrence of Osteosarcoma and Unfavorable Survival Outcomes of the Patients. J Cancer 2019; 10:2091-2101. [PMID: 31205570 PMCID: PMC6548156 DOI: 10.7150/jca.28480] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 02/23/2019] [Indexed: 12/21/2022] Open
Abstract
Osteosarcoma (OS) is the most common primary bone malignancy, predominately affecting children and adolescents. Due to the introduction of chemotherapy, the 5-year survival rate of OS patients has dramatically improved to 60-70%. Unfortunately, OS patients with recurrence or metastatic disease have less than a 20% chance of long-term survival, despite aggressive therapies. In this study, we aimed to identify gene expression patterns associated with metastasis and recurrence in order to identify potential biomarkers with prognostic power. We found that high expression of polyglutamine tract-binding protein 1 (PQBP1) and low expression of phosphoenolpyruvate carboxykinase 2 (PCK2) were related to a high probability of recurrence and metastasis in OS patients and also predicted shorter recurrence-free survival (RFS) and metastasis-free survival (MFS) after adjustment for other clinical variables. Prediction models based on the combination of PQBP1 and PCK2 expression had good and robust predictive power for recurrence and metastasis. A PQBP1 and PCK2-centered protein interaction network was built, and the hypothetical regulatory path between them was identified and termed the PQBP1-SF3A2-UBA52-PCK2 axis. Gene enrichment analysis indicated that aberrations of metabolism might play an important role in recurrence and metastasis in OS patients. Accordingly, PQBP1 and PCK2 are crucial for recurrence and metastasis in OS, and these findings provide a molecular basis for the exploitation of diagnostic and therapeutic strategies for overcoming recurrence and metastasis in OS.
Collapse
Affiliation(s)
- Yong Zhang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, China
| | - Haiyue Zhao
- Center of Reproduction and Genetics, Suzhou Municipal Hospital, Affiliated Suzhou Hospital of Nanjing Medical University, 26 Daoqian Road, Suzhou, Jiangsu 215002, China
| | - Wu Xu
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, China
| | - Dinghua Jiang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, China
| | - Lixin Huang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, China
| | - Lisong Li
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, China
| |
Collapse
|
12
|
SHOC2-MRAS-PP1 complex positively regulates RAF activity and contributes to Noonan syndrome pathogenesis. Proc Natl Acad Sci U S A 2018; 115:E10576-E10585. [PMID: 30348783 DOI: 10.1073/pnas.1720352115] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Dephosphorylation of the inhibitory "S259" site on RAF kinases (S259 on CRAF, S365 on BRAF) plays a key role in RAF activation. The MRAS GTPase, a close relative of RAS oncoproteins, interacts with SHOC2 and protein phosphatase 1 (PP1) to form a heterotrimeric holoenzyme that dephosphorylates this S259 RAF site. MRAS and SHOC2 function as PP1 regulatory subunits providing the complex with striking specificity against RAF. MRAS also functions as a targeting subunit as membrane localization is required for efficient RAF dephosphorylation and ERK pathway regulation in cells. SHOC2's predicted structure shows remarkable similarities to the A subunit of PP2A, suggesting a case of convergent structural evolution with the PP2A heterotrimer. We have identified multiple regions in SHOC2 involved in complex formation as well as residues in MRAS switch I and the interswitch region that help account for MRAS's unique effector specificity for SHOC2-PP1. MRAS, SHOC2, and PPP1CB are mutated in Noonan syndrome, and we show that syndromic mutations invariably promote complex formation with each other, but not necessarily with other interactors. Thus, Noonan syndrome in individuals with SHOC2, MRAS, or PPPC1B mutations is likely driven at the biochemical level by enhanced ternary complex formation and highlights the crucial role of this phosphatase holoenzyme in RAF S259 dephosphorylation, ERK pathway dynamics, and normal human development.
Collapse
|
13
|
Winkler C, Rouget R, Wu D, Beullens M, Van Eynde A, Bollen M. Overexpression of PP1-NIPP1 limits the capacity of cells to repair DNA double-strand breaks. J Cell Sci 2018; 131:jcs.214932. [PMID: 29898919 DOI: 10.1242/jcs.214932] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/29/2018] [Indexed: 12/20/2022] Open
Abstract
The ubiquitously expressed nuclear protein NIPP1 (also known as PPP1R8) recruits phosphoproteins for regulated dephosphorylation by the associated protein phosphatase PP1. To bypass the PP1 titration artifacts seen upon NIPP1 overexpression, we have engineered covalently linked fusions of PP1 and NIPP1, and demonstrate their potential to selectively explore the function of the PP1:NIPP1 holoenzyme. By using inducible stable cell lines, we show that PP1-NIPP1 fusions cause replication stress in a manner that requires both PP1 activity and substrate recruitment via the ForkHead Associated domain of NIPP1. More specifically, PP1-NIPP1 expression resulted in the build up of RNA-DNA hybrids (R-loops), enhanced chromatin compaction and a diminished repair of DNA double-strand breaks (DSBs), culminating in the accumulation of DSBs. These effects were associated with a reduced expression of DNA damage signaling and repair proteins. Our data disclose a key role for dephosphorylation of PP1:NIPP1 substrates in setting the threshold for DNA repair, and indicate that activators of this phosphatase hold therapeutic potential as sensitizers for DNA-damaging agents.
Collapse
Affiliation(s)
- Claudia Winkler
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| | - Raphael Rouget
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| | - Dan Wu
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| | - Monique Beullens
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| | - Aleyde Van Eynde
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| | - Mathieu Bollen
- Laboratory of Biosignaling & Therapeutics, KU Leuven Department of Cellular and Molecular Medicine, University of Leuven, B-3000 Leuven, Belgium
| |
Collapse
|
14
|
Mizuguchi M, Obita T, Kajiyama A, Kozakai Y, Nakai T, Nabeshima Y, Okazawa H. Allosteric modulation of the binding affinity between PQBP1 and the spliceosomal protein U5-15kD. FEBS Lett 2016; 590:2221-31. [PMID: 27314904 DOI: 10.1002/1873-3468.12256] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/30/2016] [Accepted: 06/08/2016] [Indexed: 01/31/2023]
Abstract
Polyglutamine tract-binding protein 1 (PQBP1) is an intrinsically disordered protein composed of a small folded WW domain and a long disordered region. PQBP1 binds to spliceosomal proteins WBP11 and U5-15kD through its N-terminal WW domain and C-terminal region, respectively. Here, we reveal that the binding between PQBP1 and WBP11 reduces the binding affinity between PQBP1 and U5-15kD. Our results suggest that the interaction between PQBP1 and WBP11 negatively modulates the U5-15kD binding of PQBP1 by an allosteric mechanism.
Collapse
Affiliation(s)
- Mineyuki Mizuguchi
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan.,Graduate School of Innovative Life Science, University of Toyama, Japan
| | - Takayuki Obita
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan
| | - Asagi Kajiyama
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan
| | - Yuki Kozakai
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan
| | - Tsuyoshi Nakai
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan
| | - Yuko Nabeshima
- Faculty of Pharmaceutical Sciences, University of Toyama, Japan
| | - Hitoshi Okazawa
- Department of Neuropathology, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Japan.,Center for Brain Integration Research, Tokyo Medical and Dental University, Bunkyo-ku, Japan
| |
Collapse
|
15
|
Rebelo S, Santos M, Martins F, da Cruz e Silva EF, da Cruz e Silva OA. Protein phosphatase 1 is a key player in nuclear events. Cell Signal 2015; 27:2589-98. [DOI: 10.1016/j.cellsig.2015.08.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/31/2015] [Accepted: 08/10/2015] [Indexed: 12/17/2022]
|
16
|
Shkreta L, Chabot B. The RNA Splicing Response to DNA Damage. Biomolecules 2015; 5:2935-77. [PMID: 26529031 PMCID: PMC4693264 DOI: 10.3390/biom5042935] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/20/2015] [Accepted: 10/16/2015] [Indexed: 12/29/2022] Open
Abstract
The number of factors known to participate in the DNA damage response (DDR) has expanded considerably in recent years to include splicing and alternative splicing factors. While the binding of splicing proteins and ribonucleoprotein complexes to nascent transcripts prevents genomic instability by deterring the formation of RNA/DNA duplexes, splicing factors are also recruited to, or removed from, sites of DNA damage. The first steps of the DDR promote the post-translational modification of splicing factors to affect their localization and activity, while more downstream DDR events alter their expression. Although descriptions of molecular mechanisms remain limited, an emerging trend is that DNA damage disrupts the coupling of constitutive and alternative splicing with the transcription of genes involved in DNA repair, cell-cycle control and apoptosis. A better understanding of how changes in splice site selection are integrated into the DDR may provide new avenues to combat cancer and delay aging.
Collapse
Affiliation(s)
- Lulzim Shkreta
- Microbiologie et d'Infectiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada.
| | - Benoit Chabot
- Microbiologie et d'Infectiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada.
| |
Collapse
|
17
|
Wan D, Zhang ZC, Zhang X, Li Q, Han J. X chromosome-linked intellectual disability protein PQBP1 associates with and regulates the translation of specific mRNAs. Hum Mol Genet 2015; 24:4599-614. [DOI: 10.1093/hmg/ddv191] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 05/19/2015] [Indexed: 01/08/2023] Open
|
18
|
Ito H, Shiwaku H, Yoshida C, Homma H, Luo H, Chen X, Fujita K, Musante L, Fischer U, Frints SGM, Romano C, Ikeuchi Y, Shimamura T, Imoto S, Miyano S, Muramatsu SI, Kawauchi T, Hoshino M, Sudol M, Arumughan A, Wanker EE, Rich T, Schwartz C, Matsuzaki F, Bonni A, Kalscheuer VM, Okazawa H. In utero gene therapy rescues microcephaly caused by Pqbp1-hypofunction in neural stem progenitor cells. Mol Psychiatry 2015; 20:459-71. [PMID: 25070536 PMCID: PMC4378255 DOI: 10.1038/mp.2014.69] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 04/10/2014] [Accepted: 05/12/2014] [Indexed: 12/21/2022]
Abstract
Human mutations in PQBP1, a molecule involved in transcription and splicing, result in a reduced but architecturally normal brain. Examination of a conditional Pqbp1-knockout (cKO) mouse with microcephaly failed to reveal either abnormal centrosomes or mitotic spindles, increased neurogenesis from the neural stem progenitor cell (NSPC) pool or increased cell death in vivo. Instead, we observed an increase in the length of the cell cycle, particularly for the M phase in NSPCs. Corresponding to the developmental expression of Pqbp1, the stem cell pool in vivo was decreased at E10 and remained at a low level during neurogenesis (E15) in Pqbp1-cKO mice. The expression profiles of NSPCs derived from the cKO mouse revealed significant changes in gene groups that control the M phase, including anaphase-promoting complex genes, via aberrant transcription and RNA splicing. Exogenous Apc4, a hub protein in the network of affected genes, recovered the cell cycle, proliferation, and cell phenotypes of NSPCs caused by Pqbp1-cKO. These data reveal a mechanism of brain size control based on the simple reduction of the NSPC pool by cell cycle time elongation. Finally, we demonstrated that in utero gene therapy for Pqbp1-cKO mice by intraperitoneal injection of the PQBP1-AAV vector at E10 successfully rescued microcephaly with preserved cortical structures and improved behavioral abnormalities in Pqbp1-cKO mice, opening a new strategy for treating this intractable developmental disorder.
Collapse
Affiliation(s)
- H Ito
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - H Shiwaku
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - C Yoshida
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - H Homma
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - H Luo
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - X Chen
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - K Fujita
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - L Musante
- Department of Human Molecular Genetics, Max-Planck Institute for Molecular Genetics, Berlin-Dahlem, Germany
| | - U Fischer
- Department of Human Molecular Genetics, Max-Planck Institute for Molecular Genetics, Berlin-Dahlem, Germany
| | - S G M Frints
- Department of Clinical Genetics, University Hospital azM Maastricht, Maastricht, The Netherlands,School for Oncology and Developmental Biology, GROW, Maastricht University, Maastricht, The Netherlands
| | - C Romano
- Unità Operativa Complessa di Pediatria e Genetica Medica, IRCCS Associazione Oasi Maria Santissima, Troina (Enna), Italy
| | - Y Ikeuchi
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St Louis, MO, USA,Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - T Shimamura
- Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - S Imoto
- Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - S Miyano
- Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - S-i Muramatsu
- Department of Neurology, Jichi Medical University, Tochigi, Japan
| | - T Kawauchi
- Department of Anatomy, Keio University School of Medicine, Tokyo, Japan
| | - M Hoshino
- Department of Biochemistry and Cellular Biology, National Center for Neurology and Psychiatry, Tokyo, Japan
| | - M Sudol
- Laboratory of Signal Transduction and Proteomic Profiling, Weis Center for Research, Geisinger Clinic, Danville, PA, USA
| | - A Arumughan
- Department of Neurogenetics, Max-Delbrück Center for Molecular Medicine, Berlin-Buch, Germany
| | - E E Wanker
- Department of Neurogenetics, Max-Delbrück Center for Molecular Medicine, Berlin-Buch, Germany
| | - T Rich
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - C Schwartz
- JC Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, SC, USA
| | - F Matsuzaki
- Laboratory for Cell Asymmetry, Center for Developmental Biology, RIKEN, Chuo-ku, Kobe, Japan
| | - A Bonni
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St Louis, MO, USA,Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - V M Kalscheuer
- Department of Human Molecular Genetics, Max-Planck Institute for Molecular Genetics, Berlin-Dahlem, Germany
| | - H Okazawa
- Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan,Department of Neuropathology, Medical Research Institute and Center for Brain Integration Research, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan. E-mail:
| |
Collapse
|
19
|
Lu ZQ, Sinha A, Sharma P, Kislinger T, Gramolini AO. Proteomic Analysis of Human Fetal Atria and Ventricle. J Proteome Res 2014; 13:5869-78. [DOI: 10.1021/pr5007685] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
20
|
Iwasaki Y, Thomsen GH. The splicing factor PQBP1 regulates mesodermal and neural development through FGF signaling. Development 2014; 141:3740-51. [PMID: 25209246 DOI: 10.1242/dev.106658] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alternative splicing of pre-mRNAs is an important means of regulating developmental processes, yet the molecular mechanisms governing alternative splicing in embryonic contexts are just beginning to emerge. Polyglutamine-binding protein 1 (PQBP1) is an RNA-splicing factor that, when mutated, in humans causes Renpenning syndrome, an X-linked intellectual disability disease characterized by severe cognitive impairment, but also by physical defects that suggest PQBP1 has broader functions in embryonic development. Here, we reveal essential roles for PQBP1 and a binding partner, WBP11, in early development of Xenopus embryos. Both genes are expressed in the nascent mesoderm and neurectoderm, and morpholino knockdown of either causes defects in differentiation and morphogenesis of the mesoderm and neural plate. At the molecular level, knockdown of PQBP1 in Xenopus animal cap explants inhibits target gene induction by FGF but not by BMP, Nodal or Wnt ligands, and knockdown of either PQBP1 or WBP11 in embryos inhibits expression of fgf4 and FGF4-responsive cdx4 genes. Furthermore, PQBP1 knockdown changes the alternative splicing of FGF receptor-2 (FGFR2) transcripts, altering the incorporation of cassette exons that generate receptor variants (FGFR2 IIIb or IIIc) with different ligand specificities. Our findings may inform studies into the mechanisms underlying Renpenning syndrome.
Collapse
Affiliation(s)
- Yasuno Iwasaki
- Department of Biochemistry and Cell Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Gerald H Thomsen
- Department of Biochemistry and Cell Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY 11794-5215, USA
| |
Collapse
|
21
|
Jérôme M, Paudel HK. 14-3-3ζ regulates nuclear trafficking of protein phosphatase 1α (PP1α) in HEK-293 cells. Arch Biochem Biophys 2014; 558:28-35. [DOI: 10.1016/j.abb.2014.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/09/2014] [Accepted: 06/11/2014] [Indexed: 12/24/2022]
|
22
|
Ilinykh PA, Tigabu B, Ivanov A, Ammosova T, Obukhov Y, Garron T, Kumari N, Kovalskyy D, Platonov MO, Naumchik VS, Freiberg AN, Nekhai S, Bukreyev A. Role of protein phosphatase 1 in dephosphorylation of Ebola virus VP30 protein and its targeting for the inhibition of viral transcription. J Biol Chem 2014; 289:22723-22738. [PMID: 24936058 DOI: 10.1074/jbc.m114.575050] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The filovirus Ebola (EBOV) causes the most severe hemorrhagic fever known. The EBOV RNA-dependent polymerase complex includes a filovirus-specific VP30, which is critical for the transcriptional but not replication activity of EBOV polymerase; to support transcription, VP30 must be in a dephosphorylated form. Here we show that EBOV VP30 is phosphorylated not only at the N-terminal serine clusters identified previously but also at the threonine residues at positions 143 and 146. We also show that host cell protein phosphatase 1 (PP1) controls VP30 dephosphorylation because expression of a PP1-binding peptide cdNIPP1 increased VP30 phosphorylation. Moreover, targeting PP1 mRNA by shRNA resulted in the overexpression of SIPP1, a cytoplasm-shuttling regulatory subunit of PP1, and increased EBOV transcription, suggesting that cytoplasmic accumulation of PP1 induces EBOV transcription. Furthermore, we developed a small molecule compound, 1E7-03, that targeted a non-catalytic site of PP1 and increased VP30 dephosphorylation. The compound inhibited the transcription but increased replication of the viral genome and completely suppressed replication of EBOV in cultured cells. Finally, mutations of Thr(143) and Thr(146) of VP30 significantly inhibited EBOV transcription and strongly induced VP30 phosphorylation in the N-terminal Ser residues 29-46, suggesting a novel mechanism of regulation of VP30 phosphorylation. Our findings suggest that targeting PP1 with small molecules is a feasible approach to achieve dysregulation of the EBOV polymerase activity. This novel approach may be used for the development of antivirals against EBOV and other filovirus species.
Collapse
Affiliation(s)
- Philipp A Ilinykh
- Departments of Pathology and University of Texas Medical Branch at Galveston, Galveston, Texas 77555; Galveston National Laboratory, Galveston, Texas 77555
| | - Bersabeh Tigabu
- Departments of Pathology and University of Texas Medical Branch at Galveston, Galveston, Texas 77555; Galveston National Laboratory, Galveston, Texas 77555
| | - Andrey Ivanov
- Center for Sickle Cell Disease and Howard University, Washington, D. C. 20059
| | - Tatiana Ammosova
- Center for Sickle Cell Disease and Howard University, Washington, D. C. 20059; Departments of Medicine and Howard University, Washington, D. C. 20059
| | - Yuri Obukhov
- Center for Sickle Cell Disease and Howard University, Washington, D. C. 20059
| | - Tania Garron
- Departments of Pathology and University of Texas Medical Branch at Galveston, Galveston, Texas 77555; Galveston National Laboratory, Galveston, Texas 77555,; Departments of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, Texas 77555
| | - Namita Kumari
- Center for Sickle Cell Disease and Howard University, Washington, D. C. 20059
| | - Dmytro Kovalskyy
- Kiev National Taras Shevchenko University, Kiev 01601, Ukraine, and; Enamine Ltd., Kiev 01103, Ukraine
| | - Maxim O Platonov
- Kiev National Taras Shevchenko University, Kiev 01601, Ukraine, and; Enamine Ltd., Kiev 01103, Ukraine
| | - Vasiliy S Naumchik
- Kiev National Taras Shevchenko University, Kiev 01601, Ukraine, and; Enamine Ltd., Kiev 01103, Ukraine
| | - Alexander N Freiberg
- Departments of Pathology and University of Texas Medical Branch at Galveston, Galveston, Texas 77555; Galveston National Laboratory, Galveston, Texas 77555
| | - Sergei Nekhai
- Galveston National Laboratory, Galveston, Texas 77555,; Departments of Medicine and Howard University, Washington, D. C. 20059; Departments of Microbiology, Howard University, Washington, D. C. 20059,.
| | - Alexander Bukreyev
- Departments of Pathology and University of Texas Medical Branch at Galveston, Galveston, Texas 77555; Galveston National Laboratory, Galveston, Texas 77555,; Departments of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, Texas 77555,.
| |
Collapse
|
23
|
Ikeuchi Y, de la Torre-Ubieta L, Matsuda T, Steen H, Okazawa H, Bonni A. The XLID protein PQBP1 and the GTPase Dynamin 2 define a signaling link that orchestrates ciliary morphogenesis in postmitotic neurons. Cell Rep 2013; 4:879-89. [PMID: 23994472 DOI: 10.1016/j.celrep.2013.07.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 07/17/2013] [Accepted: 07/26/2013] [Indexed: 10/26/2022] Open
Abstract
Intellectual disability (ID) is a prevalent developmental disorder of cognition that remains incurable. Here, we report that knockdown of the X-linked ID (XLID) protein polyglutamine-binding protein 1 (PQBP1) in neurons profoundly impairs the morphogenesis of the primary cilium, including in the mouse cerebral cortex in vivo. PQBP1 is localized at the base of the neuronal cilium, and targeting its WW effector domain to the cilium stimulates ciliary morphogenesis. We also find that PQBP1 interacts with Dynamin 2 and thereby inhibits its GTPase activity. Accordingly, Dynamin 2 knockdown in neurons stimulates ciliogenesis and suppresses the PQBP1 knockdown-induced ciliary phenotype. Strikingly, a mutation of the PQBP1 WW domain that causes XLID disrupts its ability to interact with and inhibit Dynamin 2 and to induce neuronal ciliogenesis. These findings define PQBP1 and Dynamin 2 as components of a signaling pathway that orchestrates neuronal ciliary morphogenesis in the brain.
Collapse
Affiliation(s)
- Yoshiho Ikeuchi
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | |
Collapse
|
24
|
Mizuguchi M, Okazawa H. [Structural study of polyglutamine tract-binding protein 1]. YAKUGAKU ZASSHI 2013; 133:519-26. [PMID: 23649393 DOI: 10.1248/yakushi.13-00001-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Polyglutamine tract-binding protein 1 (PQBP1) is a nuclear protein that regulates transcription and pre-mRNA splicing. In addition, the mutations in the PQBP1 gene are known to cause hereditary mental retardation. This review summarizes current knowledge about the solution structure of PQBP1. PQBP1 is an intrinsically disordered protein: its polar-rich domain and C-terminal domain are disordered under physiological conditions. PQBP1 binds to its target molecule U5-15kD via a continuous 23-residue segment of the C-terminal domain. The function of PQBP1 in the pre-mRNA splicing is also discussed.
Collapse
|
25
|
Bardoni B, Abekhoukh S, Zongaro S, Melko M. Intellectual disabilities, neuronal posttranscriptional RNA metabolism, and RNA-binding proteins: three actors for a complex scenario. PROGRESS IN BRAIN RESEARCH 2012; 197:29-51. [PMID: 22541287 DOI: 10.1016/b978-0-444-54299-1.00003-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Intellectual disability (ID) is the most frequent cause of serious handicap in children and young adults and interests 2-3% of worldwide population, representing a serious problem from the medical, social, and economic points of view. The causes are very heterogeneous. Genes involved in ID have various functions altering different pathways important in neuronal function. Regulation of mRNA metabolism is particularly important in neurons for synaptic structure and function. Here, we review ID due to alteration of mRNA metabolism. Functional absence of some RNA-binding proteins--namely, FMRP, FMR2P, PQBP1, UFP3B, VCX-A--causes different forms of ID. These proteins are involved in different steps of RNA metabolism and, even if a detailed analysis of their RNA targets has been performed so far only for FMRP, it appears clear that they modulate some aspects (translation, stability, transport, and sublocalization) of a subset of RNAs coding for proteins, whose function must be relevant for neurons. Two other proteins, DYRK1A and CDKL5, involved in Down syndrome and Rett syndrome, respectively, have been shown to have an impact on splicing efficiency of specific mRNAs. Both proteins are kinases and their effect is indirect. Interestingly, both are localized in nuclear speckles, the nuclear domains where splicing factors are assembled, stocked, and recycled and influence their biogenesis and/or their organization.
Collapse
Affiliation(s)
- Barbara Bardoni
- Institute of Molecular and Cellular Pharmacology, CNRS-UMR6097, Université de Nice Sophia-Antipolis,Valbonne, France.
| | | | | | | |
Collapse
|
26
|
Kunde SA, Musante L, Grimme A, Fischer U, Muller E, Wanker EE, Kalscheuer VM. The X-chromosome-linked intellectual disability protein PQBP1 is a component of neuronal RNA granules and regulates the appearance of stress granules. Hum Mol Genet 2011; 20:4916-31. [DOI: 10.1093/hmg/ddr430] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
27
|
Tapia VE, Nicolaescu E, McDonald CB, Musi V, Oka T, Inayoshi Y, Satteson AC, Mazack V, Humbert J, Gaffney CJ, Beullens M, Schwartz CE, Landgraf C, Volkmer R, Pastore A, Farooq A, Bollen M, Sudol M. Y65C missense mutation in the WW domain of the Golabi-Ito-Hall syndrome protein PQBP1 affects its binding activity and deregulates pre-mRNA splicing. J Biol Chem 2010; 285:19391-401. [PMID: 20410308 DOI: 10.1074/jbc.m109.084525] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The PQBP1 (polyglutamine tract-binding protein 1) gene encodes a nuclear protein that regulates pre-mRNA splicing and transcription. Mutations in the PQBP1 gene were reported in several X chromosome-linked mental retardation disorders including Golabi-Ito-Hall syndrome. The missense mutation that causes this syndrome is unique among other PQBP1 mutations reported to date because it maps within a functional domain of PQBP1, known as the WW domain. The mutation substitutes tyrosine 65 with cysteine and is located within the conserved core of aromatic amino acids of the domain. We show here that the binding property of the Y65C-mutated WW domain and the full-length mutant protein toward its cognate proline-rich ligands was diminished. Furthermore, in Golabi-Ito-Hall-derived lymphoblasts we showed that the complex between PQBP1-Y65C and WBP11 (WW domain-binding protein 11) splicing factor was compromised. In these cells a substantial decrease in pre-mRNA splicing efficiency was detected. Our study points to the critical role of the WW domain in the function of the PQBP1 protein and provides an insight into the molecular mechanism that underlies the X chromosome-linked mental retardation entities classified globally as Renpenning syndrome.
Collapse
Affiliation(s)
- Victor E Tapia
- Institut für Medizinische Immunologie, Charité-Universitätsmedizin Berlin, Berlin 10115, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Hayano T, Koiwai K, Ishii H, Maezawa S, Kouda K, Motoyama T, Kubota T, Koiwai O. TdT interacting factor 1 enhances TdT ubiquitylation through recruitment of BPOZ-2 into nucleus from cytoplasm. Genes Cells 2009; 14:1415-27. [PMID: 19930467 DOI: 10.1111/j.1365-2443.2009.01358.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Takahide Hayano
- Faculty of Science & Technology, Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Kofler M, Schuemann M, Merz C, Kosslick D, Schlundt A, Tannert A, Schaefer M, Lührmann R, Krause E, Freund C. Proline-rich sequence recognition: I. Marking GYF and WW domain assembly sites in early spliceosomal complexes. Mol Cell Proteomics 2009; 8:2461-73. [PMID: 19483244 DOI: 10.1074/mcp.m900191-mcp200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proline-rich sequences (PRS) and their recognition domains have emerged as transposable protein interaction modules during eukaryotic evolution. They are especially abundant in proteins associated with pre-mRNA splicing and likely assist in the formation of the spliceosome by binding to GYF and WW domains. Here we profile PRS-mediated interactions of the CD2BP2/52K GYF domain by a site-specific peptide inhibitor and stable isotope labeling/mass spectrometry analysis. Several PRS hubs with multiple proline-rich motifs exist that can recruit GYF and/or WW domains. Saturating the PRS sites by an isolated GYF domain inhibited splicing at the level of A complex formation. The interactions mediated by PRS are therefore important to the early phases of spliceosomal assembly.
Collapse
Affiliation(s)
- Michael Kofler
- Protein Engineering Group, Leibniz Institute for Molecular Pharmacology and Freie Universität Berlin, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Devogelaere B, Sammels E, De Smedt H. The IRBIT domain adds new functions to the AHCY family. Bioessays 2008; 30:642-52. [PMID: 18536033 DOI: 10.1002/bies.20772] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
During the past few years, the IRBIT domain has emerged as an important add-on of S-adenosyl-L-homocystein hydrolase (AHCY), thereby creating the new family of AHCY-like proteins. In this review, we discuss the currently available data on this new family of proteins. We describe the IRBIT domain as a unique part of these proteins and give an overview of its regulation via (de)phosphorylation and proteolysis. The second part of this review is focused on the potential functions of the AHCY-like proteins. We propose that the IRBIT domain serves as an anchor for targeting AHCY-like proteins towards cytoplasmic targets. This leads to regulation of (i) intracellular Ca2+ via the inositol 1,4,5-trisphosphate receptor (IP3R), (ii) intracellular pH via the Na+/HCO3 - cotransporters (NBCs); whereas inactivation of the IRBIT domain induces (iii) nuclear translocation and regulation of AHCY activity. Dysfunction of AHCY-like proteins will disturb these three important functions, with various biological implications.
Collapse
Affiliation(s)
- Benoit Devogelaere
- Laboratory of Molecular and Cellular Signalling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Belgium
| | | | | |
Collapse
|
31
|
Rodríguez-Muñoz R, Villarreal-Silva M, González-Ramírez R, García-Sierra F, Mondragón M, Mondragón R, Cerna J, Cisneros B. Neuronal differentiation modulates the dystrophin Dp71d binding to the nuclear matrix. Biochem Biophys Res Commun 2008; 375:303-7. [PMID: 18687308 DOI: 10.1016/j.bbrc.2008.07.135] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Accepted: 07/22/2008] [Indexed: 10/21/2022]
Abstract
The function of dystrophin Dp71 in neuronal cells remains unknown. To approach this issue, we have selected the PC12 neuronal cell line. These cells express both a Dp71f cytoplasmic variant and a Dp71d nuclear isoform. In this study, we demonstrated by electron and confocal microscopy analyses of in situ nuclear matrices and Western blotting evaluation of cell extracts that Dp71d associates with the nuclear matrix. Interestingly, this binding is modulated during NGF-induced neuronal differentiation of PC12 cells with a twofold increment in the differentiated cells, compared to control cells. Also, distribution of Dp71d along the periphery of the nuclear matrix observed in the undifferentiated cells is replaced by intense fluorescent foci localized in the center of the nucleoskeletal structure. In summary, we revealed that Dp71d is a dynamic component of nuclear matrix that might participate in the nuclear modeling occurring during neuronal differentiation.
Collapse
Affiliation(s)
- Rafael Rodríguez-Muñoz
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Avenida Instituto Politécnico Nacional 2508, Apartado Postal 14-740, C.P. 07360, México D.F., Mexico
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Genoud T, Schweizer F, Tscheuschler A, Debrieux D, Casal JJ, Schäfer E, Hiltbrunner A, Fankhauser C. FHY1 mediates nuclear import of the light-activated phytochrome A photoreceptor. PLoS Genet 2008; 4:e1000143. [PMID: 18670649 PMCID: PMC2483295 DOI: 10.1371/journal.pgen.1000143] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Accepted: 06/25/2008] [Indexed: 01/30/2023] Open
Abstract
The phytochrome (phy) family of photoreceptors is of crucial importance throughout the life cycle of higher plants. Light-induced nuclear import is required for most phytochrome responses. Nuclear accumulation of phyA is dependent on two related proteins called FHY1 (Far-red elongated HYpocotyl 1) and FHL (FHY1 Like), with FHY1 playing the predominant function. The transcription of FHY1 and FHL are controlled by FHY3 (Far-red elongated HYpocotyl 3) and FAR1 (FAr-red impaired Response 1), a related pair of transcription factors, which thus indirectly control phyA nuclear accumulation. FHY1 and FHL preferentially interact with the light-activated form of phyA, but the mechanism by which they enable photoreceptor accumulation in the nucleus remains unsolved. Sequence comparison of numerous FHY1-related proteins indicates that only the NLS located at the N-terminus and the phyA-interaction domain located at the C-terminus are conserved. We demonstrate that these two parts of FHY1 are sufficient for FHY1 function. phyA nuclear accumulation is inhibited in the presence of high levels of FHY1 variants unable to enter the nucleus. Furthermore, nuclear accumulation of phyA becomes light- and FHY1-independent when an NLS sequence is fused to phyA, strongly suggesting that FHY1 mediates nuclear import of light-activated phyA. In accordance with this idea, FHY1 and FHY3 become functionally dispensable in seedlings expressing a constitutively nuclear version of phyA. Our data suggest that the mechanism uncovered in Arabidopsis is conserved in higher plants. Moreover, this mechanism allows us to propose a model explaining why phyA needs a specific nuclear import pathway.
Collapse
Affiliation(s)
- Thierry Genoud
- Centre for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Fabian Schweizer
- Centre for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Anke Tscheuschler
- Institut für Biologie II/Botanik, Albert Ludwigs Universität, Freiburg, Germany
| | - Dimitry Debrieux
- Centre for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Jorge J. Casal
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Eberhard Schäfer
- Institut für Biologie II/Botanik, Albert Ludwigs Universität, Freiburg, Germany
- BIOSS, Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Andreas Hiltbrunner
- Institut für Biologie II/Botanik, Albert Ludwigs Universität, Freiburg, Germany
- BIOSS, Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | | |
Collapse
|
33
|
Nicolaescu E, Beullens M, Lesage B, Keppens S, Himpens B, Bollen M. Nature of the nuclear inclusions formed by PQBP1, a protein linked to neurodegenerative polyglutamine diseases. Eur J Cell Biol 2008; 87:817-29. [PMID: 18599155 DOI: 10.1016/j.ejcb.2008.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 05/15/2008] [Accepted: 05/19/2008] [Indexed: 11/29/2022] Open
Abstract
PQBP1, for polyglutamine tract-binding protein-1, has been linked to progressive neurodegenerative diseases, such as spinocerebellar ataxia, that are caused by the expansion of a polyglutamine repeat in a key regulatory protein. The overexpression of PQBP1 results in the formation of nuclear inclusions, reminiscent of the protein aggregates that are detected in polyglutamine diseases. We show here that the occurrence of PQBP1-induced nuclear inclusions is dramatically increased by the co-expression of the pre-mRNA splicing factor SIPP1, a protein ligand of PQBP1. These nuclear inclusions did not co-localise with nuclear structures such as nucleoli, coiled bodies, PML bodies, speckles and stress bodies, and were not associated with (in)active chromatin or with nucleic acids. Site-directed mutagenesis showed that the facilitation in the formation of the nuclear inclusions required multiple independent interaction sites between SIPP1 and PQBP1. Moreover, the nuclear inclusions were highly dynamic and their formation did not require energy. Our data suggest that the SIPP1-PQBP1-induced nuclear inclusions are distinct from the protein aggregates that are associated with polyglutamine diseases and represent dynamic nucleoplasmic heteropolymers of SIPP1 and PQBP1.
Collapse
Affiliation(s)
- Emilia Nicolaescu
- Laboratory of Biosignaling and Therapeutics, Department of Molecular Cell Biology, University of Leuven, Campus Gasthuisberg, O&N1/Box901, Herestraat 49, B-3000 Leuven, Belgium
| | | | | | | | | | | |
Collapse
|
34
|
Sangiambut S, Keelapang P, Aaskov J, Puttikhunt C, Kasinrerk W, Malasit P, Sittisombut N. Multiple regions in dengue virus capsid protein contribute to nuclear localization during virus infection. J Gen Virol 2008; 89:1254-1264. [PMID: 18420804 DOI: 10.1099/vir.0.83264-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
During infection, the capsid (C) protein of many flaviviruses localizes to the nuclei and nucleoli of several infected cell lines; the underlying basis and significance of C protein nuclear localization remain poorly understood. In this study, double alanine-substitution mutations were introduced into three previously proposed nuclear-localization signals (at positions 6-9, 73-76 and 85-100) of dengue virus C protein, and four viable mutants, c(K6A,K7A), c(K73A,K74A), c(R85A,K86A) and c(R97A,R98A), were generated in a mosquito cell line in which C protein nuclear localization was rarely observed. Indirect immunofluorescence analysis revealed that, whilst C protein was present in the nuclei of PS and Vero cells throughout infection with a dengue serotype 2 parent virus, the substitution mutations in c(K73A,K74A) and c(R85A,K86A) resulted in an elimination of nuclear localization in PS cells and marked reduction in Vero cells. Mutants c(K6A,K7A) and c(R97A,R98A) exhibited reduced nuclear localization at the late period of infection in PS cells only. All four mutants displayed reduced replication in PS, Vero and C6/36 cells, but there was a lack of correlation between nuclear localization and viral growth properties. Distinct dibasic residues within dengue virus C protein, many of which were located on the solvent-exposed side of the C protein homodimer, contribute to its ability to localize to nuclei during virus infection.
Collapse
Affiliation(s)
- Sutha Sangiambut
- Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand
| | - Poonsook Keelapang
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - John Aaskov
- School of Life Sciences, Queensland University of Technology, 2 George Street, Brisbane 4001, Australia
| | - Chunya Puttikhunt
- Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand
| | - Watchara Kasinrerk
- Department of Clinical Immunology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.,Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand
| | - Prida Malasit
- Medical Molecular Biology Unit, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.,Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand
| | - Nopporn Sittisombut
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok 10700, Thailand
| |
Collapse
|
35
|
Krol HA, Krawczyk PM, Bosch KS, Aten JA, Hol EM, Reits EA. Polyglutamine expansion accelerates the dynamics of ataxin-1 and does not result in aggregate formation. PLoS One 2008; 3:e1503. [PMID: 18231590 PMCID: PMC2200796 DOI: 10.1371/journal.pone.0001503] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Accepted: 12/26/2007] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Polyglutamine expansion disorders are caused by an expansion of the polyglutamine (polyQ) tract in the disease related protein, leading to severe neurodegeneration. All polyQ disorders are hallmarked by the presence of intracellular aggregates containing the expanded protein in affected neurons. The polyQ disorder SpinoCerebellar Ataxia 1 (SCA1) is caused by a polyQ-expansion in the ataxin-1 protein, which is thought to lead to nuclear aggregates. METHODOLOGY/PRINCIPAL FINDINGS Using advanced live cell fluorescence microscopy and a filter retardation assay we show that nuclear accumulations formed by polyQ-expanded ataxin-1 do not resemble aggregates of other polyQ-expanded proteins. Instead of being static, insoluble aggregates, nuclear accumulations formed by the polyQ-expanded ataxin-1 showed enhanced intracellular kinetics as compared to wild-type ataxin-1. During mitosis, ataxin-1 accumulations redistributed equally among daughter cells, in contrast to polyQ aggregates. Interestingly, polyQ expansion did not affect the nuclear-cytoplasmic shuttling of ataxin-1 as proposed before. CONCLUSIONS/SIGNIFICANCE These results indicate that polyQ expansion does not necessarily lead to aggregate formation, and that the enhanced kinetics may affect the nuclear function of ataxin-1. The unexpected findings for a polyQ-expanded protein and their consequences for ongoing SCA1 research are discussed.
Collapse
Affiliation(s)
- Hilde A. Krol
- Department of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Przemek M. Krawczyk
- Department of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Klazien S. Bosch
- Department of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Jacob A. Aten
- Department of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Elly M. Hol
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences Amsterdam, Amsterdam, The Netherlands
| | - Eric A. Reits
- Department of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
36
|
Guo F, Wang Y, Zhang YZ. Construction of two recombination yeast two-hybrid vectors by in vitro recombination. Mol Biotechnol 2007; 36:38-43. [PMID: 17827536 DOI: 10.1007/s12033-007-0018-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/29/2022]
Abstract
Recombination-based restrictionless, ligation-independent cloning has been proven to be advantageous over restriction digestion and ligation cloning. To utilize the recombination cloning and previously constructed two-hybrid cDNA libraries, a new Gateway yeast two-hybrid bait vector, pEZY202, and a new prey vector, pEZY45, were constructed. The two-hybrid vectors were generated by in vitro recombination using a protocol that can be easily adapted for the conversion of other existing vectors. The new vectors were used to assay the interaction between the WW domain of PQBP1 (PQBPww) and the WW domain binding protein WBP11. Both PQBPww and WBP11 were cloned into a Gateway donor vector by in vitro recombination. They were then subcloned into pEZY45 and pEZY202, respectively, by in vitro recombination. The binding between PQBPww and WBP11 was reported in a two-hybrid experiment using the new vectors. The results of testing the new vectors in combination with the original vectors indicated that the new bait vector could be used to screen cDNA libraries that are constructed using the original prey vectors.
Collapse
Affiliation(s)
- Feng Guo
- Department of Biology, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, USA
| | | | | |
Collapse
|
37
|
Lesage B, Beullens M, Pedelini L, Garcia-Gimeno MA, Waelkens E, Sanz P, Bollen M. A complex of catalytically inactive protein phosphatase-1 sandwiched between Sds22 and inhibitor-3. Biochemistry 2007; 46:8909-19. [PMID: 17630778 DOI: 10.1021/bi7003119] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Protein Ser/Thr phosphatase-1 (PP1) associates with a host of proteins to form substrate-specific holoenzymes. Sds22 and Inhibitor-3 (I3) are two independently described ancient interactors of PP1. We show here by various approaches that Sds22 and I3 form a heterotrimeric complex with PP1, both in cell lysates and after purification. The stability of the complex depended on functional PP1 interaction sites in Sds22 and I3, indicating that PP1 is sandwiched between Sds22 and I3. Intriguingly, I3 could not be replaced in this complex by another PP1 interactor with the same PP1 binding motif. In vitro, Sds22 and I3 were potent inhibitors of PP1, but with only some substrates. The inhibition by Sds22 could be reproduced with synthetic Sds22 fragments comprising leucine-rich repeats (LRR) 2 and 5. Sds22 and LRR5 also slowly converted PP1 into a conformation that was inactive with all tested substrates. Cell lysates that were prepared under conditions that prevented the Sds22-induced inactivation of PP1 contained a catalytically inactive complex of Sds22, PP1, and I3, indicating that this complex exists in vivo. Therefore, our studies show that a pool of PP1 is complexly controlled by both Sds22 and I3.
Collapse
Affiliation(s)
- Bart Lesage
- Laboratory of Biosignaling and Therapeutics, Department of Molecular Cell Biology, Faculty of Medicine, Catholic University of Leuven, B-3000 Leuven, Belgium
| | | | | | | | | | | | | |
Collapse
|
38
|
Abstract
GYF domains are small, versatile adaptor domains that recognize proline-rich sequences (PRS). They are present in most eukaryotic species sequenced so far, but in contrast to other PRS-recognition domains (PRD), GYF domains have not experienced the same amplification in metazoa during evolution. Mutational and structural analysis has shown the conserved signature W-X-Y-X(6-11)-GPF-X(4)-M-X(2)-W-X(3)-GYF to be the site of interaction with proline-rich peptides. In contrast, composition and length of the C-terminal half of GYF domains are not conserved. Similar to other PRD, GYF domains bind to many different PRS that converge on a minimal consensus sequence. All GYF domains analyzed so far selected for the core motif PPG, whereas amino-acid preferences adjacent to this motif vary. As a result of this analysis, two subfamilies have been identified: CD2BP2-type and SMY2-type GYF domains. The latter subfamily comprises most GYF domains and is characterized by a shorter beta(1)-beta(2) loop and an aspartate instead of the tryptophan found at position 8 in CD2BP2-type GYF domains. Recent analysis of binding specificities for GYF domains allowed identification of novel interaction partners. Thereby proteomics has contributed to a functional understanding of GYF domain-containing proteins and sets the stage for a more systematic investigation of their functions in vivo.
Collapse
Affiliation(s)
- Michael M Kofler
- Protein Engineering Group, Free University and FMP Berlin, Germany.
| | | |
Collapse
|