1
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Chen Y, Chen Y, Li Q, Liu H, Han J, Zhang H, Cheng L, Lin G. Short C-terminal Musashi-1 proteins regulate pluripotency states in embryonic stem cells. Cell Rep 2023; 42:113308. [PMID: 37858462 DOI: 10.1016/j.celrep.2023.113308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/04/2023] [Accepted: 10/03/2023] [Indexed: 10/21/2023] Open
Abstract
The RNA-binding protein Musashi-1 (MSI1) regulates the proliferation and differentiation of adult stem cells. However, its role in embryonic stem cells (ESCs) and early embryonic development remains poorly understood. Here, we report the presence of short C-terminal MSI1 (MSI1-C) proteins in early mouse embryos and mouse ESCs, but not in human ESCs, under conventional culture conditions. In mouse embryos and mESCs, deletion of MSI1-C together with full-length MSI1 causes early embryonic developmental arrest and pluripotency dissolution. MSI1-C is induced upon naive induction and facilitates hESC naive pluripotency acquisition, elevating the pluripotency of primed hESCs toward a formative-like state. MSI1-C proteins are nuclear localized and bind to RNAs involved in DNA-damage repair (including MLH1, BRCA1, and MSH2), conferring on hESCs better survival in human-mouse interspecies cell competition and prolonged ability to form blastoids. This study identifies MSI1-C as an essential regulator in ESC pluripotency states and early embryonic development.
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Affiliation(s)
- Youwei Chen
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China; Clinical Center for Brain and Spinal Cord Research, Medical School, Tongji University, Shanghai, China
| | - Ying Chen
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Qianyan Li
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Huahua Liu
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jiazhen Han
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Hailin Zhang
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Liming Cheng
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China; Clinical Center for Brain and Spinal Cord Research, Medical School, Tongji University, Shanghai, China.
| | - Gufa Lin
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China; Clinical Center for Brain and Spinal Cord Research, Medical School, Tongji University, Shanghai, China.
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2
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Bertoldo JB, Müller S, Hüttelmaier S. RNA-binding proteins in cancer drug discovery. Drug Discov Today 2023; 28:103580. [PMID: 37031812 DOI: 10.1016/j.drudis.2023.103580] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/25/2023] [Accepted: 03/29/2023] [Indexed: 04/11/2023]
Abstract
RNA-binding proteins (RBPs) are crucial players in tumorigenesis and, hence, promising targets in cancer drug discovery. However, they are largely regarded as 'undruggable', because of the often noncatalytic and complex interactions between protein and RNA, which limit the discovery of specific inhibitors. Nonetheless, over the past 10 years, drug discovery efforts have uncovered RBP inhibitors with clinical relevance, highlighting the disruption of RNA-protein networks as a promising avenue for cancer therapeutics. In this review, we discuss the role of structurally distinct RBPs in cancer, and the mechanisms of RBP-directed small-molecule inhibitors (SMOIs) focusing on drug-protein interactions, binding surfaces, potency, and translational potential. Additionally, we underline the limitations of RBP-targeting drug discovery assays and comment on future trends in the field.
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Affiliation(s)
- Jean B Bertoldo
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW, Australia; School of Clinical Medicine, UNSW Sydney, Sydney, NSW, Australia
| | - Simon Müller
- Institute for Molecular Medicine, Faculty of Medicine, Martin-Luther University of Halle-Wittenberg, Halle (Saale), Germany; New York Genome Center, New York, NY, USA; Department of Biology, New York University, New York, NY, USA
| | - Stefan Hüttelmaier
- Institute for Molecular Medicine, Faculty of Medicine, Martin-Luther University of Halle-Wittenberg, Halle (Saale), Germany.
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3
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Nishikino T, Miyanoiri Y. Site-Specific Isotope Labeling of FliG for Studying Structural Dynamics Using Nuclear Magnetic Resonance Spectroscopy. Methods Mol Biol 2023; 2646:57-70. [PMID: 36842106 DOI: 10.1007/978-1-0716-3060-0_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
To understand flagella-driven motility of bacteria, it is important to understand the structure and dynamics of the flagellar motor machinery. We have conducted structural dynamics analyses using solution nuclear magnetic resonance (NMR) to elucidate the detailed functions of flagellar motor proteins. Here, we introduce the analysis of the FliG protein, which is a flagellar motor protein, focusing on the preparation method of the original stable isotope-labeled protein.
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Affiliation(s)
- Tatsuro Nishikino
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Yohei Miyanoiri
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan.
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4
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Hosoe Y, Miyanoiri Y, Re S, Ochi S, Asahina Y, Kawakami T, Kuroda M, Mizuguchi K, Oda M. Structural dynamics of the N‐terminal
SH2
domain of
PI3K
in its free and
CD28
‐bound states. FEBS J 2022; 290:2366-2378. [PMID: 36282120 DOI: 10.1111/febs.16666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/29/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
Protein conformational changes with fluctuations are fundamental aspects of protein-protein interactions (PPIs); understanding these motions is required for the rational design of PPI-regulating compounds. Src homology 2 (SH2) domains are commonly found in adapter proteins involved in signal transduction and specifically bind to consensus motifs of proteins containing phosphorylated tyrosine (pY). Here, we analysed the interaction between the N-terminal SH2 domain (nSH2) of the regulatory subunit in phosphoinositide 3-kinase (PI3K) and the cytoplasmic region of the T-cell co-receptor, CD28, using NMR and molecular dynamics (MD) simulations. First, we assigned the backbone signals of nSH2 on 1 H-15 N heteronuclear single quantum coherence spectra in the absence or presence of the CD28 phosphopeptide, SDpYMNMTPRRPG. Chemical shift perturbation experiments revealed allosteric changes at the BC loop and the C-terminal region of nSH2 upon CD28 binding. NMR relaxation experiments showed a conformational exchange associated with CD28 binding in these regions. The conformational stabilisation of the C-terminal region correlated with the regulation of PI3K catalytic function. Further, using 19 F- and 31 P-labelled CD28 phosphopeptide, we analysed the structural dynamics of CD28 and demonstrated that the aromatic ring of the pY residue fluctuated between multiple conformations upon nSH2 binding. Our MD simulations largely explained the NMR results and the structural dynamics of nSH2 and CD28 in both bound and unbound states. Notably, in addition to its major conformation, we detected a minor conformation of nSH2 in the CD28 bound state that may explain the allosteric conformational change in the BC loop.
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Affiliation(s)
- Yuhi Hosoe
- Graduate School of Life and Environmental Sciences Kyoto Prefectural University Japan
| | | | - Suyong Re
- Artificial Intelligence Center for Health and Biomedical Research National Institutes of Biomedical Innovation, Health, and Nutrition Osaka Japan
| | - Saki Ochi
- Graduate School of Life and Environmental Sciences Kyoto Prefectural University Japan
| | - Yuya Asahina
- Institute for Protein Research Osaka University Japan
| | - Toru Kawakami
- Institute for Protein Research Osaka University Japan
| | - Masataka Kuroda
- Artificial Intelligence Center for Health and Biomedical Research National Institutes of Biomedical Innovation, Health, and Nutrition Osaka Japan
- Discovery Technology Laboratories Mitsubishi Tanabe Pharma Corporation Yokohama Japan
| | - Kenji Mizuguchi
- Institute for Protein Research Osaka University Japan
- Artificial Intelligence Center for Health and Biomedical Research National Institutes of Biomedical Innovation, Health, and Nutrition Osaka Japan
| | - Masayuki Oda
- Graduate School of Life and Environmental Sciences Kyoto Prefectural University Japan
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5
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Darai N, Mahalapbutr P, Wolschann P, Lee VS, Wolfinger MT, Rungrotmongkol T. Theoretical studies on RNA recognition by Musashi 1 RNA-binding protein. Sci Rep 2022; 12:12137. [PMID: 35840700 PMCID: PMC9287312 DOI: 10.1038/s41598-022-16252-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 07/07/2022] [Indexed: 01/12/2023] Open
Abstract
The Musashi (MSI) family of RNA-binding proteins, comprising the two homologs Musashi-1 (MSI1) and Musashi-2 (MSI2), typically regulates translation and is involved in cell proliferation and tumorigenesis. MSI proteins contain two ribonucleoprotein-like RNA-binding domains, RBD1 and RBD2, that bind single-stranded RNA motifs with a central UAG trinucleotide with high affinity and specificity. The finding that MSI also promotes the replication of Zika virus, a neurotropic Flavivirus, has triggered further investigations of the biochemical principles behind MSI–RNA interactions. However, a detailed molecular understanding of the specificity of MSI RBD1/2 interaction with RNA is still missing. Here, we performed computational studies of MSI1–RNA association complexes, investigating different RNA pentamer motifs using molecular dynamics simulations with binding free energy calculations based on the solvated interaction energy method. Simulations with Alphafold2 suggest that predicted MSI protein structures are highly similar to experimentally determined structures. The binding free energies show that two out of four RNA pentamers exhibit a considerably higher binding affinity to MSI1 RBD1 and RBD2, respectively. The obtained structural information on MSI1 RBD1 and RBD2 will be useful for a detailed functional and mechanistic understanding of this type of RNA–protein interactions.
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Affiliation(s)
- Nitchakan Darai
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Panupong Mahalapbutr
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Peter Wolschann
- Department of Theoretical Chemistry, University of Vienna, Währinger Strasse 17, 1090, Vienna, Austria
| | - Vannajan Sanghiran Lee
- Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Michael T Wolfinger
- Department of Theoretical Chemistry, University of Vienna, Währinger Strasse 17, 1090, Vienna, Austria. .,Research Group Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Währinger Strasse 29, 1090, Vienna, Austria.
| | - Thanyada Rungrotmongkol
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, 10330, Thailand. .,Center of Excellence in Biocatalyst and Sustainable Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
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6
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Wang J, Lan L, Wu X, Xu L, Miao Y. Mechanism of RNA recognition by a Musashi RNA-binding protein. Curr Res Struct Biol 2021; 4:10-20. [PMID: 34988468 PMCID: PMC8695263 DOI: 10.1016/j.crstbi.2021.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/31/2021] [Accepted: 12/07/2021] [Indexed: 12/21/2022] Open
Abstract
The Musashi RNA-binding proteins (RBPs) regulate translation of target mRNAs and maintenance of cell stemness and tumorigenesis. Musashi-1 (MSI1), long considered as an intestinal and neural stem cell marker, has been more recently found to be over expressed in many cancers. It has served as an important drug target for treating acute myeloid leukemia and solid tumors such as ovarian, colorectal and bladder cancer. One of the reported binding targets of MSI1 is Numb, a negative regulator of the Notch signaling. However, the dynamic mechanism of Numb RNA binding to MSI1 remains unknown, largely hindering effective drug design targeting this critical interaction. Here, we have performed extensive all-atom microsecond-timescale simulations using a robust Gaussian accelerated molecular dynamics (GaMD) method, which successfully captured multiple times of spontaneous and highly accurate binding of the Numb RNA from bulk solvent to the MSI1 protein target site. GaMD simulations revealed that Numb RNA binding to MSI1 involved largely induced fit in both the RNA and protein. The simulations also identified important low-energy intermediate conformational states during RNA binding, in which Numb interacted mainly with the β2-β3 loop and C terminus of MSI1. The mechanistic understanding of RNA binding obtained from our GaMD simulations is expected to facilitate rational structure-based drug design targeting MSI1 and other RBPs.
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Affiliation(s)
- Jinan Wang
- Center for Computational Biology, University of Kansas, Lawrence, KS, 66047, USA
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Lan Lan
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Xiaoqing Wu
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Liang Xu
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
- Department of Radiation Oncology, The University of Kansas Cancer Center, Kansas City, KS, 66160, USA
| | - Yinglong Miao
- Center for Computational Biology, University of Kansas, Lawrence, KS, 66047, USA
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
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7
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Human oncoprotein Musashi-2 N-terminal RNA recognition motif backbone assignment and identification of RNA-binding pocket. Oncotarget 2017; 8:106587-106597. [PMID: 29290973 PMCID: PMC5739758 DOI: 10.18632/oncotarget.22540] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/30/2017] [Indexed: 12/13/2022] Open
Abstract
RNA-binding protein Musashi-2 (MSI2) is a key regulator in stem cells, it is over-expressed in a variety of cancers and its higher expression is associated with poor prognosis. Like Musashi-1, it contains two N-terminal RRMs (RNA-recognition Motifs, also called RBDs (RNA-binding Domains)), RRM1 and RRM2, which mediate the binding to their target mRNAs. Previous studies have obtained the three-dimensional structures of the RBDs of Musashi-1 and the RBD1:RNA complex. Here we show the binding of MSI2-RRM1 to a 15nt Numb RNA in Fluorescence Polarization assay and time resolved Fluorescence Resonance Energy Transfer assay. Using nuclear magnetic resonance (NMR) spectroscopy we assigned the backbone resonances of MSI2-RRM1, and characterized the direct interaction of RRM1 to Numb RNA r(GUAGU). Our NMR titration and structure modeling studies showed that MSI2-RRM1 and MSI1-RBD1 have similar RNA binding events and binding pockets. This work adds significant information to MSI2-RRM1 structure and RNA binding pocket, and contributes to the development of MSI2 specific and MSI1/MSI2 dual inhibitors.
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8
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Iwaoka R, Nagata T, Tsuda K, Imai T, Okano H, Kobayashi N, Katahira M. Backbone and side chain assignments of the second RNA-binding domain of Musashi-1 in its free form and in complex with 5-mer RNA. BIOMOLECULAR NMR ASSIGNMENTS 2017; 11:265-268. [PMID: 28808919 DOI: 10.1007/s12104-017-9760-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
Musashi1 (Msi1) is an RNA-binding protein that is involved in cell fate determination. Here, we report the 1H, 15N, and 13C resonance assignments of Msi1 second RNA-binding domain in free form and in complex with RNA. The assignments can be utilized for NMR structure and dynamics analyses of the Msi1:RNA complex, and moreover, for chemical shift perturbation analyses to evaluate the binding of potential small molecule inhibitors against Msi1:RNA interaction.
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Affiliation(s)
- Ryo Iwaoka
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
- Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Takashi Nagata
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
- Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
| | - Kengo Tsuda
- RIKEN Center for Life Science Technologies, 1-7-22 Suehirocho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Takao Imai
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Naohiro Kobayashi
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Masato Katahira
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
- Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
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9
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Structural Insight into the Recognition of r(UAG) by Musashi-1 RBD2, and Construction of a Model of Musashi-1 RBD1-2 Bound to the Minimum Target RNA. Molecules 2017; 22:molecules22071207. [PMID: 28753936 PMCID: PMC6152312 DOI: 10.3390/molecules22071207] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/14/2017] [Accepted: 07/14/2017] [Indexed: 12/23/2022] Open
Abstract
Musashi-1 (Msi1) controls the maintenance of stem cells and tumorigenesis through binding to its target mRNAs and subsequent translational regulation. Msi1 has two RNA-binding domains (RBDs), RBD1 and RBD2, which recognize r(GUAG) and r(UAG), respectively. These minimal recognition sequences are connected by variable linkers in the Msi1 target mRNAs, however, the molecular mechanism by which Msi1 recognizes its targets is not yet understood. We previously determined the solution structure of the Msi1 RBD1:r(GUAGU) complex. Here, we determined the first structure of the RBD2:r(GUAGU) complex. The structure revealed that the central trinucleotide, r(UAG), is specifically recognized by the intermolecular hydrogen-bonding and aromatic stacking interactions. Importantly, the C-terminal region, which is disordered in the free form, took a certain conformation, resembling a helix. The observation of chemical shift perturbation and intermolecular NOEs, together with increases in the heteronuclear steady-state {1H}-15N NOE values on complex formation, indicated the involvement of the C-terminal region in RNA binding. On the basis of the two complex structures, we built a structural model of consecutive RBDs with r(UAGGUAG) containing both minimal recognition sequences, which resulted in no steric hindrance. The model suggests recognition of variable lengths (n) of the linker up to n = 50 may be possible.
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10
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Kudinov AE, Karanicolas J, Golemis EA, Boumber Y. Musashi RNA-Binding Proteins as Cancer Drivers and Novel Therapeutic Targets. Clin Cancer Res 2017; 23:2143-2153. [PMID: 28143872 DOI: 10.1158/1078-0432.ccr-16-2728] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 12/12/2022]
Abstract
Aberrant gene expression that drives human cancer can arise from epigenetic dysregulation. Although much attention has focused on altered activity of transcription factors and chromatin-modulating proteins, proteins that act posttranscriptionally can potently affect expression of oncogenic signaling proteins. The RNA-binding proteins (RBP) Musashi-1 (MSI1) and Musashi-2 (MSI2) are emerging as regulators of multiple critical biological processes relevant to cancer initiation, progression, and drug resistance. Following identification of Musashi as a regulator of progenitor cell identity in Drosophila, the human Musashi proteins were initially linked to control of maintenance of hematopoietic stem cells, then stem cell compartments for additional cell types. More recently, the Musashi proteins were found to be overexpressed and prognostic of outcome in numerous cancer types, including colorectal, lung, and pancreatic cancers; glioblastoma; and several leukemias. MSI1 and MSI2 bind and regulate the mRNA stability and translation of proteins operating in essential oncogenic signaling pathways, including NUMB/Notch, PTEN/mTOR, TGFβ/SMAD3, MYC, cMET, and others. On the basis of these activities, MSI proteins maintain cancer stem cell populations and regulate cancer invasion, metastasis, and development of more aggressive cancer phenotypes, including drug resistance. Although RBPs are viewed as difficult therapeutic targets, initial efforts to develop MSI-specific inhibitors are promising, and RNA interference-based approaches to inhibiting these proteins have had promising outcomes in preclinical studies. In the interim, understanding the function of these translational regulators may yield insight into the relationship between mRNA expression and protein expression in tumors, guiding tumor-profiling analysis. This review provides a current overview of Musashi as a cancer driver and novel therapeutic target. Clin Cancer Res; 23(9); 2143-53. ©2017 AACR.
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Affiliation(s)
- Alexander E Kudinov
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | - John Karanicolas
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | - Erica A Golemis
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | - Yanis Boumber
- Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania. .,Department of Hematology/Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania
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11
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Fox RG, Park FD, Koechlein CS, Kritzik M, Reya T. Musashi Signaling in Stem Cells and Cancer. Annu Rev Cell Dev Biol 2015; 31:249-67. [DOI: 10.1146/annurev-cellbio-100814-125446] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Raymond G. Fox
- Department of Pharmacology,
- Moores Cancer Center, and
- Sanford Consortium for Regenerative Medicine, La Jolla, California 92037
| | - Frederick D. Park
- Department of Pharmacology,
- Moores Cancer Center, and
- Division of Gastroenterology, University of California San Diego School of Medicine, La Jolla, California 92093;
- Sanford Consortium for Regenerative Medicine, La Jolla, California 92037
| | - Claire S. Koechlein
- Department of Pharmacology,
- Moores Cancer Center, and
- Sanford Consortium for Regenerative Medicine, La Jolla, California 92037
| | - Marcie Kritzik
- Department of Pharmacology,
- Moores Cancer Center, and
- Sanford Consortium for Regenerative Medicine, La Jolla, California 92037
| | - Tannishtha Reya
- Department of Pharmacology,
- Moores Cancer Center, and
- Sanford Consortium for Regenerative Medicine, La Jolla, California 92037
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12
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Moroz LL, Kohn AB. Unbiased View of Synaptic and Neuronal Gene Complement in Ctenophores: Are There Pan-neuronal and Pan-synaptic Genes across Metazoa? Integr Comp Biol 2015; 55:1028-49. [PMID: 26454853 DOI: 10.1093/icb/icv104] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Hypotheses of origins and evolution of neurons and synapses are controversial, mostly due to limited comparative data. Here, we investigated the genome-wide distribution of the bilaterian "synaptic" and "neuronal" protein-coding genes in non-bilaterian basal metazoans (Ctenophora, Porifera, Placozoa, and Cnidaria). First, there are no recognized genes uniquely expressed in neurons across all metazoan lineages. None of the so-called pan-neuronal genes such as embryonic lethal abnormal vision (ELAV), Musashi, or Neuroglobin are expressed exclusively in neurons of the ctenophore Pleurobrachia. Second, our comparative analysis of about 200 genes encoding canonical presynaptic and postsynaptic proteins in bilaterians suggests that there are no true "pan-synaptic" genes or genes uniquely and specifically attributed to all classes of synapses. The majority of these genes encode receptive and secretory complexes in a broad spectrum of eukaryotes. Trichoplax (Placozoa) an organism without neurons and synapses has more orthologs of bilaterian synapse-related/neuron-related genes than do ctenophores-the group with well-developed neuronal and synaptic organization. Third, the majority of genes encoding ion channels and ionotropic receptors are broadly expressed in unicellular eukaryotes and non-neuronal tissues in metazoans. Therefore, they cannot be viewed as neuronal markers. Nevertheless, the co-expression of multiple types of ion channels and receptors does correlate with the presence of neural and synaptic organization. As an illustrative example, the ctenophore genomes encode a greater diversity of ion channels and ionotropic receptors compared with the genomes of the placozoan Trichoplax and the demosponge Amphimedon. Surprisingly, both placozoans and sponges have a similar number of orthologs of "synaptic" proteins as we identified in the genomes of two ctenophores. Ctenophores have a distinct synaptic organization compared with other animals. Our analysis of transcriptomes from 10 different ctenophores did not detect recognized orthologs of synthetic enzymes encoding several classical, low-molecular-weight (neuro)transmitters; glutamate signaling machinery is one of the few exceptions. Novel peptidergic signaling molecules were predicted for ctenophores, together with the diversity of putative receptors including SCNN1/amiloride-sensitive sodium channel-like channels, many of which could be examples of a lineage-specific expansion within this group. In summary, our analysis supports the hypothesis of independent evolution of neurons and, as corollary, a parallel evolution of synapses. We suggest that the formation of synaptic machinery might occur more than once over 600 million years of animal evolution.
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Affiliation(s)
- Leonid L Moroz
- *The Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Blvd, St Augustine, FL 32080, USA; Department of Neuroscience, McKnight Brain Institute and Whitney Laboratory for Marine Biosciences, University of Florida, Gainesville, FL 32611, USA
| | - Andrea B Kohn
- *The Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Blvd, St Augustine, FL 32080, USA
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13
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Lan L, Appelman C, Smith AR, Yu J, Larsen S, Marquez RT, Liu H, Wu X, Gao P, Roy A, Anbanandam A, Gowthaman R, Karanicolas J, De Guzman RN, Rogers S, Aubé J, Ji M, Cohen RS, Neufeld KL, Xu L. Natural product (-)-gossypol inhibits colon cancer cell growth by targeting RNA-binding protein Musashi-1. Mol Oncol 2015; 9:1406-20. [PMID: 25933687 DOI: 10.1016/j.molonc.2015.03.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 03/09/2015] [Accepted: 03/27/2015] [Indexed: 02/07/2023] Open
Abstract
Musashi-1 (MSI1) is an RNA-binding protein that acts as a translation activator or repressor of target mRNAs. The best-characterized MSI1 target is Numb mRNA, whose encoded protein negatively regulates Notch signaling. Additional MSI1 targets include the mRNAs for the tumor suppressor protein APC that regulates Wnt signaling and the cyclin-dependent kinase inhibitor P21(WAF-1). We hypothesized that increased expression of NUMB, P21 and APC, through inhibition of MSI1 RNA-binding activity might be an effective way to simultaneously downregulate Wnt and Notch signaling, thus blocking the growth of a broad range of cancer cells. We used a fluorescence polarization assay to screen for small molecules that disrupt the binding of MSI1 to its consensus RNA binding site. One of the top hits was (-)-gossypol (Ki = 476 ± 273 nM), a natural product from cottonseed, known to have potent anti-tumor activity and which has recently completed Phase IIb clinical trials for prostate cancer. Surface plasmon resonance and nuclear magnetic resonance studies demonstrate a direct interaction of (-)-gossypol with the RNA binding pocket of MSI1. We further showed that (-)-gossypol reduces Notch/Wnt signaling in several colon cancer cell lines having high levels of MSI1, with reduced SURVIVIN expression and increased apoptosis/autophagy. Finally, we showed that orally administered (-)-gossypol inhibits colon cancer growth in a mouse xenograft model. Our study identifies (-)-gossypol as a potential small molecule inhibitor of MSI1-RNA interaction, and suggests that inhibition of MSI1's RNA binding activity may be an effective anti-cancer strategy.
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Affiliation(s)
- Lan Lan
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Carl Appelman
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Amber R Smith
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Jia Yu
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA; School of Chemistry and Chemical Engineering, Southeast University, Nanjing, China
| | - Sarah Larsen
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Rebecca T Marquez
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Hao Liu
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Xiaoqing Wu
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Philip Gao
- COBRE Protein Production Group, The University of Kansas, Lawrence, KS, USA
| | - Anuradha Roy
- High Throughput Screening Laboratory, The University of Kansas, Lawrence, KS, USA
| | | | - Ragul Gowthaman
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA; Center for Bioinformatics, The University of Kansas, Lawrence, KS, USA
| | - John Karanicolas
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA; Center for Bioinformatics, The University of Kansas, Lawrence, KS, USA
| | - Roberto N De Guzman
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Steven Rogers
- Center of Biomedical Research Excellence, Center for Cancer Experimental Therapeutics, The University of Kansas, Lawrence, KS, USA
| | - Jeffrey Aubé
- Center of Biomedical Research Excellence, Center for Cancer Experimental Therapeutics, The University of Kansas, Lawrence, KS, USA; Specialized Chemistry Center, The University of Kansas, Lawrence, KS, USA; Center for Chemical Methodologies and Library Development, The University of Kansas, Lawrence, KS, USA; Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS, USA
| | - Min Ji
- School of Chemistry and Chemical Engineering, Southeast University, Nanjing, China
| | - Robert S Cohen
- Department of Biological Sciences, Clemson University, Clemson, SC, USA
| | - Kristi L Neufeld
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA
| | - Liang Xu
- Department of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA; Department of Radiation Oncology, The University of Kansas Cancer Center, Kansas City, KS, USA.
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14
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Zearfoss NR, Deveau LM, Clingman CC, Schmidt E, Johnson ES, Massi F, Ryder SP. A conserved three-nucleotide core motif defines Musashi RNA binding specificity. J Biol Chem 2014; 289:35530-41. [PMID: 25368328 DOI: 10.1074/jbc.m114.597112] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Musashi (MSI) family proteins control cell proliferation and differentiation in many biological systems. They are overexpressed in tumors of several origins, and their expression level correlates with poor prognosis. MSI proteins control gene expression by binding RNA and regulating its translation. They contain two RNA recognition motif (RRM) domains, which recognize a defined sequence element. The relative contribution of each nucleotide to the binding affinity and specificity is unknown. We analyzed the binding specificity of three MSI family RRM domains using a quantitative fluorescence anisotropy assay. We found that the core element driving recognition is the sequence UAG. Nucleotides outside of this motif have a limited contribution to binding free energy. For mouse MSI1, recognition is determined by the first of the two RRM domains. The second RRM adds affinity but does not contribute to binding specificity. In contrast, the recognition element for Drosophila MSI is more extensive than the mouse homolog, suggesting functional divergence. The short nature of the binding determinant suggests that protein-RNA affinity alone is insufficient to drive target selection by MSI family proteins.
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Affiliation(s)
- N Ruth Zearfoss
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Laura M Deveau
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Carina C Clingman
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Eric Schmidt
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Emily S Johnson
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Francesca Massi
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Sean P Ryder
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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15
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Clingman CC, Deveau LM, Hay SA, Genga RM, Shandilya SMD, Massi F, Ryder SP. Allosteric inhibition of a stem cell RNA-binding protein by an intermediary metabolite. eLife 2014; 3. [PMID: 24935936 PMCID: PMC4094780 DOI: 10.7554/elife.02848] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 06/15/2014] [Indexed: 01/22/2023] Open
Abstract
Gene expression and metabolism are coupled at numerous levels. Cells must sense and respond to nutrients in their environment, and specialized cells must synthesize metabolic products required for their function. Pluripotent stem cells have the ability to differentiate into a wide variety of specialized cells. How metabolic state contributes to stem cell differentiation is not understood. In this study, we show that RNA-binding by the stem cell translation regulator Musashi-1 (MSI1) is allosterically inhibited by 18-22 carbon ω-9 monounsaturated fatty acids. The fatty acid binds to the N-terminal RNA Recognition Motif (RRM) and induces a conformational change that prevents RNA association. Musashi proteins are critical for development of the brain, blood, and epithelium. We identify stearoyl-CoA desaturase-1 as a MSI1 target, revealing a feedback loop between ω-9 fatty acid biosynthesis and MSI1 activity. We propose that other RRM proteins could act as metabolite sensors to couple gene expression changes to physiological state.
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Affiliation(s)
- Carina C Clingman
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Laura M Deveau
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Samantha A Hay
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Ryan M Genga
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Shivender M D Shandilya
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Francesca Massi
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Sean P Ryder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
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16
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Hadziselimovic N, Vukojevic V, Peter F, Milnik A, Fastenrath M, Fenyves B, Hieber P, Demougin P, Vogler C, de Quervain DF, Papassotiropoulos A, Stetak A. Forgetting Is Regulated via Musashi-Mediated Translational Control of the Arp2/3 Complex. Cell 2014; 156:1153-1166. [DOI: 10.1016/j.cell.2014.01.054] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 11/27/2013] [Accepted: 01/17/2014] [Indexed: 01/21/2023]
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17
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Plateroti M, de Araujo PR, da Silva AE, Penalva LOF. The RNA-Binding Protein Musashi1: A Major Player in Intestinal Epithelium Renewal and Colon Cancer Development. CURRENT COLORECTAL CANCER REPORTS 2012; 8:290-297. [PMID: 23914149 DOI: 10.1007/s11888-012-0141-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Aberrant gene expression is the cause and the consequence of tumorigenesis. A major component of gene expression is translation regulation; a process whose main players are RNA-binding-proteins (RBPs). More than 800 RBPs have been identified in the human genome and several of them have been shown to control gene networks associated with relevant cancer processes. A more systematic characterization of RBPs starts to reveal that similar to transcription factors, they can function as tumor suppressors or oncogenes. A relevant example is Musashi1 (Msi1), which is emerging as a critical regulator of tumorigenesis in multiple cancer types, including colon cancer. Msi1 is a stem marker in several tissues and is critical in maintaining the balance between self-renewal and differentiation. However, a boost in Msi1 expression can most likely lead cells towards an oncogenic pathway. In this article, we discuss the parallels between Msi1 function in normal renewal of intestinal epithelium and in colon cancer.
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Affiliation(s)
- Michelina Plateroti
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Université Claude Bernard Lyon 1, France. 16 Rue Raphael Dubois, 69622 Villeurbanne, Cedex France
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18
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Ohyama T, Nagata T, Tsuda K, Kobayashi N, Imai T, Okano H, Yamazaki T, Katahira M. Structure of Musashi1 in a complex with target RNA: the role of aromatic stacking interactions. Nucleic Acids Res 2011; 40:3218-31. [PMID: 22140116 PMCID: PMC3326303 DOI: 10.1093/nar/gkr1139] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Mammalian Musashi1 (Msi1) is an RNA-binding protein that regulates the translation of target mRNAs, and participates in the maintenance of cell ‘stemness’ and tumorigenesis. Msi1 reportedly binds to the 3′-untranslated region of mRNA of Numb, which encodes Notch inhibitor, and impedes initiation of its translation by competing with eIF4G for PABP binding, resulting in triggering of Notch signaling. Here, the mechanism by which Msi1 recognizes the target RNA sequence using its Ribonucleoprotein (RNP)-type RNA-binding domains (RBDs), RBD1 and RBD2 has been revealed on identification of the minimal binding RNA for each RBD and determination of the three-dimensional structure of the RBD1:RNA complex. Unique interactions were found for the recognition of the target sequence by Msi1 RBD1: adenine is sandwiched by two phenylalanines and guanine is stacked on the tryptophan in the loop between β1 and α1. The minimal recognition sequences that we have defined for Msi1 RBD1 and RBD2 have actually been found in many Msi1 target mRNAs reported to date. The present study provides molecular clues for understanding the biology involving Musashi family proteins.
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Affiliation(s)
- Takako Ohyama
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
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19
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Spears E, Neufeld KL. Novel double-negative feedback loop between adenomatous polyposis coli and Musashi1 in colon epithelia. J Biol Chem 2011; 286:4946-50. [PMID: 21199875 DOI: 10.1074/jbc.c110.205922] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Loss of tumor suppressor adenomatous polyposis coli (APC) is thought to initiate the majority of all colorectal cancers. The predominant theory of colorectal carcinogenesis implicates stem cells as the initiating cells. However, relatively little is known about the function of APC in governing the homeostasis of normal intestinal stem cells. Here, we identify a novel double-negative feedback loop between APC and a translation inhibitor protein, Musashi1 (MSI1), in cultured human colonocytes. We show APC as a key factor in MSI1 regulation through Wnt signaling and identify APC mRNA as a novel target of translational inhibition by MSI1. We propose that APC/MSI1 interactions maintain homeostatic balance in the intestinal epithelium.
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Affiliation(s)
- Erick Spears
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045, USA
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20
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MacNicol MC, Cragle CE, MacNicol AM. Context-dependent regulation of Musashi-mediated mRNA translation and cell cycle regulation. Cell Cycle 2011; 10:39-44. [PMID: 21191181 DOI: 10.4161/cc.10.1.14388] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Musashi-mediated mRNA translational control has been implicated in the promotion of physiological and pathological stem cell proliferation. During self-renewal of mammalian stem cells, Musashi has been proposed to act to repress the translation of mRNAs encoding inhibitors of cell cycle progression. By contrast, in maturing Xenopus oocytes Musashi activates translation of target mRNAs that encode proteins promoting cell cycle progression. The mechanisms directing Musashi to differentially control mRNA translation in mammalian stem cells and Xenopus oocytes is unknown. In this study, we demonstrate that the mechanisms defining Musashi function lie within the cellular context. Specifically, we show that murine Musashi acts as an activator of translation in maturing Xenopus oocytes while Xenopus Musashi functions as a repressor of target mRNA translation in mammalian cells. We further demonstrate that within the context of a primary mammalian neural stem/progenitor cell, Musashi can be converted from a repressor of mRNA translation to an activator of translation in response to extracellular stimuli. We present current models of Musashi-mediated mRNA translational control and discuss possible mechanisms for regulating Musashi function. An understanding of these mechanisms presents exciting possibilities for development of therapeutic targets to control physiological and pathological stem cell proliferation.
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Affiliation(s)
- Melanie C MacNicol
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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21
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Furukawa A, Nagata T, Matsugami A, Habu Y, Sugiyama R, Hayashi F, Kobayashi N, Yokoyama S, Takaku H, Katahira M. Structure, interaction and real-time monitoring of the enzymatic reaction of wild-type APOBEC3G. EMBO J 2009; 28:440-51. [PMID: 19153609 DOI: 10.1038/emboj.2008.290] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Indexed: 12/29/2022] Open
Abstract
Human APOBEC3G exhibits anti-human immunodeficiency virus-1 (HIV-1) activity by deaminating cytidines of the minus strand of HIV-1. Here, we report a solution structure of the C-terminal deaminase domain of wild-type APOBEC3G. The interaction with DNA was examined. Many differences in the interaction were found between the wild type and recently studied mutant APOBEC3Gs. The position of the substrate cytidine, together with that of a DNA chain, in the complex, was deduced. Interestingly, the deamination reaction of APOBEC3G was successfully monitored using NMR signals in real time. Real-time monitoring has revealed that the third cytidine of the d(CCCA) segment is deaminated at an early stage and that then the second one is deaminated at a late stage, the first one not being deaminated at all. This indicates that the deamination is carried out in a strict 3' --> 5' order. Virus infectivity factor (Vif) of HIV-1 counteracts the anti-HIV-1 activity of APOBEC3G. The structure of the N-terminal domain of APOBEC3G, with which Vif interacts, was constructed with homology modelling. The structure implies the mechanism of species-specific sensitivity of APOBEC3G to Vif action.
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Affiliation(s)
- Ayako Furukawa
- Supramolecular Biology, International Graduate School of Arts and Sciences, Yokohama City University, Yokohama, Japan
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22
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Ye F, Zhou C, Cheng Q, Shen J, Chen H. Stem-cell-abundant proteins Nanog, Nucleostemin and Musashi1 are highly expressed in malignant cervical epithelial cells. BMC Cancer 2008; 8:108. [PMID: 18419830 PMCID: PMC2387168 DOI: 10.1186/1471-2407-8-108] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Accepted: 04/18/2008] [Indexed: 12/15/2022] Open
Abstract
Background Nanog, nucleostemin (NS) and musashi1 (Msi1) are proteins that are highly expressed in undifferentiated embryonic stem (ES) cells and have been shown to be essential in maintaining the pluripotency and regulating the proliferation and asymmetric division of ES cells and several nervous system tumor cells. The roles of Nanog, NS and Msi1 in development and progression of cervical carcinoma have, until now, not been well documented. Methods In this study, expression of Nanog, NS and Msi1 was detected by immunohistochemistry analysis in 235 patients with various degrees of cervical epithelial lesions, including 49 with normal cervical epithelia, 31 with mild dysplasia (CIN I), 77 with moderate-severe dysplasia (CIN II-III) and 78 with squamous cervical carcinomas (SCCs). Associations with various clinical pathological prognostic variables were analyzed in 50 early-stage SCC patients. Results Nanog, NS and Msi1 expression levels were significantly higher in SCC patients compared with CIN patients, and were higher in CIN patients compared with those with normal cervical epithelia. Nanog expression levels showed significantly differences according to different tumor sizes (P < 0.05), whereas there were no differences in NS and Msi1 expression levels according to different clinical pathological parameters. Conclusion Our findings indicate that Nanog, NS and Msi1 may be involved in carcinogenesis of the cervix and progression of cervical carcinoma.
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Affiliation(s)
- Feng Ye
- Women's Reproductive Health Laboratory of Zhejiang Province, Women's Hospital, School of Medicine, Zhejiang University, Xueshi Rd #2, Hangzhou, 310006, China.
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23
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Jarymowycz VA, Stone MJ. Fast time scale dynamics of protein backbones: NMR relaxation methods, applications, and functional consequences. Chem Rev 2007; 106:1624-71. [PMID: 16683748 DOI: 10.1021/cr040421p] [Citation(s) in RCA: 317] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Virginia A Jarymowycz
- Department of Chemistry and Interdisciplinary Biochemistry Program, Indiana University, Bloomington, Indiana 47405-0001, USA
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24
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Enokizono Y, Konishi Y, Nagata K, Ouhashi K, Uesugi S, Ishikawa F, Katahira M. Structure of hnRNP D complexed with single-stranded telomere DNA and unfolding of the quadruplex by heterogeneous nuclear ribonucleoprotein D. J Biol Chem 2005; 280:18862-70. [PMID: 15734733 DOI: 10.1074/jbc.m411822200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heterogeneous nuclear ribonucleoprotein D, also known as AUF1, has two DNA/RNA-binding domains, each of which can specifically bind to single-stranded d(TTAGGG)n, the human telomeric repeat. Here, the structure of the C-terminal-binding domain (BD2) complexed with single-stranded d(TTAGGG) determined by NMR is presented. The structure has revealed that each residue of the d(TAG) segment is recognized by BD2 in a base-specific manner. The interactions deduced from the structure have been confirmed by gel retardation experiments with mutant BD2 and DNA. It is known that single-stranded DNA with the telomeric repeat tends to form a quadruplex and that the quadruplex has an inhibitory effect on telomere elongation by telomerase. This time it is revealed that BD2 unfolds the quadruplex of such DNA upon binding. Moreover, the effect of BD2 on the elongation by telomerase was examined in vitro. These results suggest the possible involvement of heterogeneous nuclear ribonucleoprotein D in maintenance of the telomere 3'-overhang either through protection of a single-stranded DNA or destabilization of the potentially deleterious quadruplex structure for the elongation by telomerase.
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Affiliation(s)
- Yoshiaki Enokizono
- Department of Environment and Natural Sciences, Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
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