1
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Smith BC, Silvers R. 1H, 13C, and 15N resonance assignments of the La Motif of the human La-related protein 1. BIOMOLECULAR NMR ASSIGNMENTS 2024; 18:111-118. [PMID: 38691336 DOI: 10.1007/s12104-024-10176-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 04/22/2024] [Indexed: 05/03/2024]
Abstract
Human La-related protein 1 (HsLARP1) is involved in post-transcriptional regulation of certain 5' terminal oligopyrimidine (5'TOP) mRNAs as well as other mRNAs and binds to both the 5'TOP motif and the 3'-poly(A) tail of certain mRNAs. HsLARP1 is heavily involved in cell proliferation, cell cycle defects, and cancer, where HsLARP1 is significantly upregulated in malignant cells and tissues. Like all LARPs, HsLARP1 contains a folded RNA binding domain, the La motif (LaM). Our current understanding of post-transcriptional regulation that emanates from the intricate molecular framework of HsLARP1 is currently limited to small snapshots, obfuscating our understanding of the full picture on HsLARP1 functionality in post-transcriptional events. Here, we present the nearly complete resonance assignment of the LaM of HsLARP1, providing a significant platform for future NMR spectroscopic studies.
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Affiliation(s)
- Benjamin C Smith
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, 32306, USA
| | - Robert Silvers
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, FL, 32306, USA.
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, 32306, USA.
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2
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Coleman JC, Tattersall L, Yianni V, Knight L, Yu H, Hallett SR, Johnson P, Caetano AJ, Cosstick C, Ridley AJ, Gartland A, Conte MR, Grigoriadis AE. The RNA binding proteins LARP4A and LARP4B promote sarcoma and carcinoma growth and metastasis. iScience 2024; 27:109288. [PMID: 38532886 PMCID: PMC10963253 DOI: 10.1016/j.isci.2024.109288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 11/01/2023] [Accepted: 02/16/2024] [Indexed: 03/28/2024] Open
Abstract
RNA-binding proteins (RBPs) are emerging as important regulators of cancer pathogenesis. We reveal that the RBPs LARP4A and LARP4B are differentially overexpressed in osteosarcoma and osteosarcoma lung metastases, as well as in prostate cancer. Depletion of LARP4A and LARP4B reduced tumor growth and metastatic spread in xenografts, as well as inhibiting cell proliferation, motility, and migration. Transcriptomic profiling and high-content multiparametric analyses unveiled a central role for LARP4B, but not LARP4A, in regulating cell cycle progression in osteosarcoma and prostate cancer cells, potentially through modulating key cell cycle proteins such as Cyclins B1 and E2, Aurora B, and E2F1. This first systematic comparison between LARP4A and LARP4B assigns new pro-tumorigenic functions to LARP4A and LARP4B in bone and prostate cancer, highlighting their similarities while also indicating distinct functional differences. Uncovering clear biological roles for these paralogous proteins provides new avenues for identifying tissue-specific targets and potential druggable intervention.
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Affiliation(s)
- Jennifer C. Coleman
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, SE1 1UL UK
| | - Luke Tattersall
- The Mellanby Centre for Musculoskeletal Research, Department of Oncology and Metabolism, The University of Sheffield, Sheffield, S10 2RX UK
| | - Val Yianni
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Laura Knight
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Hongqiang Yu
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Sadie R. Hallett
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, SE1 1UL UK
| | - Philip Johnson
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Ana J. Caetano
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Charlie Cosstick
- Centre for Craniofacial & Regenerative Biology, King’s College London, London, SE1 9RT UK
| | - Anne J. Ridley
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD UK
| | - Alison Gartland
- The Mellanby Centre for Musculoskeletal Research, Department of Oncology and Metabolism, The University of Sheffield, Sheffield, S10 2RX UK
| | - Maria R. Conte
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, SE1 1UL UK
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3
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Coleman JC, Hallett SR, Grigoriadis AE, Conte MR. LARP4A and LARP4B in cancer: The new kids on the block. Int J Biochem Cell Biol 2023; 161:106441. [PMID: 37356415 DOI: 10.1016/j.biocel.2023.106441] [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: 05/03/2023] [Revised: 06/09/2023] [Accepted: 06/17/2023] [Indexed: 06/27/2023]
Abstract
Recent developments have mounted a stunning body of evidence underlying the importance of RNA binding proteins (RBPs) in cancer research. In this minireview we focus on LARP4A and LARP4B, two paralogs belonging to the superfamily of La-related proteins, and provide a critical overview of current research, including their roles in cancer pathogenesis and cell proliferation, migration, cell cycle and apoptosis. We highlight current controversies surrounding LARP4A and LARP4B and conclude that their complex roles in tumorigenesis are cell-, tissue- and context-dependent, warning that caution must be exercised before categorising either protein as an oncoprotein or tumour-suppressor. We also reveal that LARP4A and LARP4B have often been confused with one another, adding uncertainty in delineating their functions. We suggest that further functional and mechanistic studies of LARP4 proteins present significant challenges for future investigations to recognise the vital contributions of these RBPs in cancer research.
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Affiliation(s)
- Jennifer C Coleman
- Centre for Craniofacial & Regenerative Biology, King's College London, London SE1 9RT, UK
| | - Sadie R Hallett
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | | | - Maria R Conte
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK.
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4
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Smith BC, Silvers R. NMR Resonance Assignment of the LA Motif of Human LA-Related Protein 1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.09.539749. [PMID: 37214987 PMCID: PMC10197598 DOI: 10.1101/2023.05.09.539749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Human La-related protein 1 (HsLARP1) is involved in post-transcriptional regulation of certain 5' s terminal oligopyrimidine (5'TOP) mRNAs as well as other mRNAs and binds to both the 5'TOP motif and the 3'-poly(A) tail of certain mRNAs. HsLARP1 is heavily involved in cell proliferation, cell cycle defects, and cancer, where HsLARP1 is significantly upregulated in malignant cells and tissues. Like all LARPs, HsLARP1 contains a folded RNA binding domain, the La motif (LaM). Our current understanding of post-transcriptional regulation that emanates from the intricate molecular framework of HsLARP1 is currently limited to small snapshots, obfuscating our understanding of the full picture on HsLARP1 functionality in post-transcriptional events. Here, we present the nearly complete resonance assignment of the LaM of HsLARP1, providing a significant platform for future NMR spectroscopic studies.
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5
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Nonsense-Mediated mRNA Decay as a Mediator of Tumorigenesis. Genes (Basel) 2023; 14:genes14020357. [PMID: 36833284 PMCID: PMC9956241 DOI: 10.3390/genes14020357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/23/2023] [Accepted: 01/26/2023] [Indexed: 02/03/2023] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved and well-characterized biological mechanism that ensures the fidelity and regulation of gene expression. Initially, NMD was described as a cellular surveillance or quality control process to promote selective recognition and rapid degradation of erroneous transcripts harboring a premature translation-termination codon (PTC). As estimated, one-third of mutated and disease-causing mRNAs were reported to be targeted and degraded by NMD, suggesting the significance of this intricate mechanism in maintaining cellular integrity. It was later revealed that NMD also elicits down-regulation of many endogenous mRNAs without mutations (~10% of the human transcriptome). Therefore, NMD modulates gene expression to evade the generation of aberrant truncated proteins with detrimental functions, compromised activities, or dominant-negative effects, as well as by controlling the abundance of endogenous mRNAs. By regulating gene expression, NMD promotes diverse biological functions during development and differentiation, and facilitates cellular responses to adaptation, physiological changes, stresses, environmental insults, etc. Mutations or alterations (such as abnormal expression, degradation, post-translational modification, etc.) that impair the function or expression of proteins associated with the NMD pathway can be deleterious to cells and may cause pathological consequences, as implicated in developmental and intellectual disabilities, genetic defects, and cancer. Growing evidence in past decades has highlighted NMD as a critical driver of tumorigenesis. Advances in sequencing technologies provided the opportunity to identify many NMD substrate mRNAs in tumor samples compared to matched normal tissues. Interestingly, many of these changes are tumor-specific and are often fine-tuned in a tumor-specific manner, suggesting the complex regulation of NMD in cancer. Tumor cells differentially exploit NMD for survival benefits. Some tumors promote NMD to degrade a subset of mRNAs, such as those encoding tumor suppressors, stress response proteins, signaling proteins, RNA binding proteins, splicing factors, and immunogenic neoantigens. In contrast, some tumors suppress NMD to facilitate the expression of oncoproteins or other proteins beneficial for tumor growth and progression. In this review, we discuss how NMD is regulated as a critical mediator of oncogenesis to promote the development and progression of tumor cells. Understanding how NMD affects tumorigenesis differentially will pave the way for the development of more effective and less toxic, targeted therapeutic opportunities in the era of personalized medicine.
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6
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Identification and molecular evolution of the La and LARP genes in 16 plant species: A focus on the Gossypium hirsutum. Int J Biol Macromol 2022; 224:1101-1117. [DOI: 10.1016/j.ijbiomac.2022.10.195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/12/2022] [Accepted: 10/20/2022] [Indexed: 11/05/2022]
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7
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Tan K, Stupack DG, Wilkinson MF. Nonsense-mediated RNA decay: an emerging modulator of malignancy. Nat Rev Cancer 2022; 22:437-451. [PMID: 35624152 PMCID: PMC11009036 DOI: 10.1038/s41568-022-00481-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/19/2022] [Indexed: 12/11/2022]
Abstract
Nonsense-mediated RNA decay (NMD) is a highly conserved RNA turnover pathway that selectively degrades RNAs harbouring truncating mutations that prematurely terminate translation, including nonsense, frameshift and some splice-site mutations. Recent studies show that NMD shapes the mutational landscape of tumours by selecting for mutations that tend to downregulate the expression of tumour suppressor genes but not oncogenes. This suggests that NMD can benefit tumours, a notion further supported by the finding that mRNAs encoding immunogenic neoantigen peptides are typically targeted for decay by NMD. Together, this raises the possibility that NMD-inhibitory therapy could be of therapeutic benefit against many tumour types, including those with a high load of neoantigen-generating mutations. Complicating this scenario is the evidence that NMD can also be detrimental for many tumour types, and consequently tumours often have perturbed NMD. NMD may suppress tumour generation and progression by degrading subsets of specific normal mRNAs, including those encoding stress-response proteins, signalling factors and other proteins beneficial for tumours, as well as pro-tumour non-coding RNAs. Together, these findings suggest that NMD-modulatory therapy has the potential to provide widespread therapeutic benefit against diverse tumour types. However, whether NMD should be stimulated or repressed requires careful analysis of the tumour to be treated.
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Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Dwayne G Stupack
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA.
- UCSD Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA.
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA.
- Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA, USA.
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8
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A genetically-encoded crosslinker screen identifies SERBP1 as a PKCε substrate influencing translation and cell division. Nat Commun 2021; 12:6934. [PMID: 34836941 PMCID: PMC8626422 DOI: 10.1038/s41467-021-27189-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 11/08/2021] [Indexed: 01/09/2023] Open
Abstract
The PKCε-regulated genome protective pathway provides transformed cells a failsafe to successfully complete mitosis. Despite the necessary role for Aurora B in this programme, it is unclear whether its requirement is sufficient or if other PKCε cell cycle targets are involved. To address this, we developed a trapping strategy using UV-photocrosslinkable amino acids encoded in the PKCε kinase domain. The validation of the mRNA binding protein SERBP1 as a PKCε substrate revealed a series of mitotic events controlled by the catalytic form of PKCε. PKCε represses protein translation, altering SERBP1 binding to the 40 S ribosomal subunit and promoting the assembly of ribonucleoprotein granules containing SERBP1, termed M-bodies. Independent of Aurora B, SERBP1 is shown to be necessary for chromosome segregation and successful cell division, correlating with M-body formation. This requirement for SERBP1 demonstrates that Aurora B acts in concert with translational regulation in the PKCε-controlled pathway exerting genome protection.
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9
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Mostovenko E, Dahm MM, Schubauer-Berigan MK, Eye T, Erdely A, Young TL, Campen MJ, Ottens AK. Serum peptidome: diagnostic window into pathogenic processes following occupational exposure to carbon nanomaterials. Part Fibre Toxicol 2021; 18:39. [PMID: 34711247 PMCID: PMC8555107 DOI: 10.1186/s12989-021-00431-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 10/08/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Growing industrial use of carbon nanotubes and nanofibers (CNT/F) warrants consideration of human health outcomes. CNT/F produces pulmonary, cardiovascular, and other toxic effects in animals along with a significant release of bioactive peptides into the circulation, the augmented serum peptidome. While epidemiology among CNT/F workers reports on few acute symptoms, there remains concern over sub-clinical CNT/F effects that may prime for chronic disease, necessitating sensitive health outcome diagnostic markers for longitudinal follow-up. METHODS Here, the serum peptidome was assessed for its biomarker potential in detecting sub-symptomatic pathobiology among CNT/F workers using label-free data-independent mass spectrometry. Studies employed a stratified design between High (> 0.5 µg/m3) and Low (< 0.1 µg/m3) inhalable CNT/F exposures in the industrial setting. Peptide biomarker model building and refinement employed linear regression and partial least squared discriminant analyses. Top-ranked peptides were then sequence identified and evaluated for pathological-relevance. RESULTS In total, 41 peptides were found to be highly discriminatory after model building with a strong linear correlation to personal CNT/F exposure. The top-five peptide model offered ideal prediction with high accuracy (Q2 = 0.99916). Unsupervised validation affirmed 43.5% of the serum peptidomic variance was attributable to CNT/F exposure. Peptide sequence identification reveals a predominant association with vascular pathology. ARHGAP21, ADAM15 and PLPP3 peptides suggest heightened cardiovasculature permeability and F13A1, FBN1 and VWDE peptides infer a pro-thrombotic state among High CNT/F workers. CONCLUSIONS The serum peptidome affords a diagnostic window into sub-symptomatic pathology among CNT/F exposed workers for longitudinal monitoring of systemic health risks.
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Affiliation(s)
- Ekaterina Mostovenko
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, PO Box 980709, Richmond, VA, 23298, USA
| | - Matthew M Dahm
- Division of Field Studies and Engineering, National Institute for Occupational Safety and Health, 1090 Tusculum Avenue, MS-R12, Cincinnati, OH, 45226, USA
| | - Mary K Schubauer-Berigan
- Division of Field Studies and Engineering, National Institute for Occupational Safety and Health, 1090 Tusculum Avenue, MS-R12, Cincinnati, OH, 45226, USA
- Evidence Synthesis and Classification Section, International Agency for Research On Cancer, 150 Cours Albert Thomas, 69372, Lyon, CEDEX 08, France
| | - Tracy Eye
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, 1095 Willowdale Road, MS-2015, Morgantown, WV, 26505, USA
| | - Aaron Erdely
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, 1095 Willowdale Road, MS-2015, Morgantown, WV, 26505, USA
| | - Tamara L Young
- Department of Pharmaceutical Sciences, University of New Mexico, MSC09 53601, Albuquerque, NM, 87131, USA
| | - Matthew J Campen
- Department of Pharmaceutical Sciences, University of New Mexico, MSC09 53601, Albuquerque, NM, 87131, USA
| | - Andrew K Ottens
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, PO Box 980709, Richmond, VA, 23298, USA.
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10
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Liang X, Wu S, Geng Z, Liu L, Zhang S, Wang S, Zhang Y, Huang Y, Zhang B. LARP7 Suppresses Endothelial-to-Mesenchymal Transition by Coupling With TRIM28. Circ Res 2021; 129:843-856. [PMID: 34503347 DOI: 10.1161/circresaha.121.319590] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Xiaodong Liang
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
| | - Shuo Wu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
| | - Zilong Geng
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
| | - Li Liu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
| | - Shasha Zhang
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
| | - Shiyan Wang
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian, China (S. Wang)
| | - Yan Zhang
- Renji-Med Clinical Stem Cell Research Center, Renji Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, China (Y.Z.)
| | - Yu Huang
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, China (Y.H.).,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China (Y.H.)
| | - Bing Zhang
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, China (X.L., S. Wu, Z.G., L.L., S.Z., B.Z.)
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11
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Jia JJ, Lahr RM, Solgaard MT, Moraes BJ, Pointet R, Yang AD, Celucci G, Graber TE, Hoang HD, Niklaus M, Pena IA, Hollensen AK, Smith EM, Chaker-Margot M, Anton L, Dajadian C, Livingstone M, Hearnden J, Wang XD, Yu Y, Maier T, Damgaard CK, Berman AJ, Alain T, Fonseca BD. mTORC1 promotes TOP mRNA translation through site-specific phosphorylation of LARP1. Nucleic Acids Res 2021; 49:3461-3489. [PMID: 33398329 PMCID: PMC8034618 DOI: 10.1093/nar/gkaa1239] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 11/29/2020] [Accepted: 12/15/2020] [Indexed: 02/06/2023] Open
Abstract
LARP1 is a key repressor of TOP mRNA translation. It binds the m7Gppp cap moiety and the adjacent 5'TOP motif of TOP mRNAs, thus impeding the assembly of the eIF4F complex on these transcripts. mTORC1 controls TOP mRNA translation via LARP1, but the details of the mechanism are unclear. Herein we elucidate the mechanism by which mTORC1 controls LARP1's translation repression activity. We demonstrate that mTORC1 phosphorylates LARP1 in vitro and in vivo, activities that are efficiently inhibited by rapamycin and torin1. We uncover 26 rapamycin-sensitive phospho-serine and -threonine residues on LARP1 that are distributed in 7 clusters. Our data show that phosphorylation of a cluster of residues located proximally to the m7Gppp cap-binding DM15 region is particularly sensitive to rapamycin and regulates both the RNA-binding and the translation inhibitory activities of LARP1. Our results unravel a new model of translation control in which the La module (LaMod) and DM15 region of LARP1, both of which can directly interact with TOP mRNA, are differentially regulated: the LaMod remains constitutively bound to PABP (irrespective of the activation status of mTORC1), while the C-terminal DM15 'pendular hook' engages the TOP mRNA 5'-end to repress translation, but only in conditions of mTORC1 inhibition.
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Affiliation(s)
- Jian-Jun Jia
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael T Solgaard
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Bruno J Moraes
- GABBA PhD Program, Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal
- PrimerGen Ltd, Viseu, Portugal
| | - Roberta Pointet
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - An-Dao Yang
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Giovanna Celucci
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Tyson E Graber
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Huy-Dung Hoang
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Marius R Niklaus
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Izabella A Pena
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Anne K Hollensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Ewan M Smith
- Cancer Research UK Beatson Institute, Glasgow, UK
| | | | - Leonie Anton
- Biozentrum, University of Basel, Basel, Switzerland
| | - Christopher Dajadian
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Mark Livingstone
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Jaclyn Hearnden
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montréal, Canada
| | - Xu-Dong Wang
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yonghao Yu
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Timm Maier
- Biozentrum, University of Basel, Basel, Switzerland
| | - Christian K Damgaard
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tommy Alain
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Bruno D Fonseca
- Children's Hospital of Eastern Ontario (CHEO) Research Institute, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
- PrimerGen Ltd, Viseu, Portugal
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12
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Feng L, Yin YY, Liu CH, Xu KR, Li QR, Wu JR, Zeng R. Proteome-wide data analysis reveals tissue-specific network associated with SARS-CoV-2 infection. J Mol Cell Biol 2021; 12:946-957. [PMID: 32642770 PMCID: PMC7454804 DOI: 10.1093/jmcb/mjaa033] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/04/2020] [Accepted: 06/11/2020] [Indexed: 12/14/2022] Open
Abstract
For patients with COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the damages to multiple organs have been clinically observed. Since most of current investigations for virus–host interaction are based on cell level, there is an urgent demand to probe tissue-specific features associated with SARS-CoV-2 infection. Based on collected proteomic datasets from human lung, colon, kidney, liver, and heart, we constructed a virus-receptor network, a virus-interaction network, and a virus-perturbation network. In the tissue-specific networks associated with virus–host crosstalk, both common and different key hubs are revealed in diverse tissues. Ubiquitous hubs in multiple tissues such as BRD4 and RIPK1 would be promising drug targets to rescue multi-organ injury and deal with inflammation. Certain tissue-unique hubs such as REEP5 might mediate specific olfactory dysfunction. The present analysis implies that SARS-CoV-2 could affect multi-targets in diverse host tissues, and the treatment of COVID-19 would be a complex task.
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Affiliation(s)
- Li Feng
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan-Yuan Yin
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cong-Hui Liu
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ke-Ren Xu
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing-Run Li
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jia-Rui Wu
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.,CAS Key Laboratory of Systems Biology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China
| | - Rong Zeng
- CAS Key Laboratory of Systems Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Mollecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.,CAS Key Laboratory of Systems Biology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China
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13
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Bayfield MA, Vinayak J, Kerkhofs K, Mansouri-Noori F. La proteins couple use of sequence-specific and non-specific binding modes to engage RNA substrates. RNA Biol 2021; 18:168-177. [PMID: 30777481 PMCID: PMC7928037 DOI: 10.1080/15476286.2019.1582955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/05/2019] [Accepted: 02/05/2019] [Indexed: 12/31/2022] Open
Abstract
La shuttles between the nucleus and cytoplasm where it binds nascent RNA polymerase III (pol III) transcripts and mRNAs, respectively. La protects the 3' end of pol III transcribed RNA precursors, such as pre-tRNAs, through the use of a well-characterized UUU-3'OH binding mode. La proteins are also RNA chaperones, and La-dependent RNA chaperone activity is hypothesized to promote pre-tRNA maturation and translation at cellular and viral internal ribosome entry sites via binding sites distinct from those used for UUU-3'OH recognition. Since the publication of La-UUU-3'OH co-crystal structures, biochemical and genetic experiments have expanded our understanding of how La proteins use UUU-3'OH-independent binding modes to make sequence-independent contacts that can increase affinity for ligands and promote RNA remodeling. Other recent work has also expanded our understanding of how La binds mRNAs through contacts to the poly(A) tail. In this review, we focus on advances in the study of La protein-RNA complex surfaces beyond the description of the La-UUU-3'OH binding mode. We highlight recent advances in the functions of expected canonical nucleic acid interaction surfaces, a heightened appreciation of disordered C-terminal regions, and the nature of sequence-independent RNA determinants in La-RNA target binding. We further discuss how these RNA binding modes may have relevance to the function of the La-related proteins.
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Affiliation(s)
- Mark A. Bayfield
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Jyotsna Vinayak
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Kyra Kerkhofs
- Department of Biology, York University, Toronto, Ontario, Canada
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14
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Mattijssen S, Kozlov G, Fonseca BD, Gehring K, Maraia RJ. LARP1 and LARP4: up close with PABP for mRNA 3' poly(A) protection and stabilization. RNA Biol 2021; 18:259-274. [PMID: 33522422 PMCID: PMC7928012 DOI: 10.1080/15476286.2020.1868753] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 12/06/2020] [Accepted: 12/17/2020] [Indexed: 02/06/2023] Open
Abstract
La-related proteins (LARPs) share a La motif (LaM) followed by an RNA recognition motif (RRM). Together these are termed the La-module that, in the prototypical nuclear La protein and LARP7, mediates binding to the UUU-3'OH termination motif of nascent RNA polymerase III transcripts. We briefly review La and LARP7 activities for RNA 3' end binding and protection from exonucleases before moving to the more recently uncovered poly(A)-related activities of LARP1 and LARP4. Two features shared by LARP1 and LARP4 are direct binding to poly(A) and to the cytoplasmic poly(A)-binding protein (PABP, also known as PABPC1). LARP1, LARP4 and other proteins involved in mRNA translation, deadenylation, and decay, contain PAM2 motifs with variable affinities for the MLLE domain of PABP. We discuss a model in which these PABP-interacting activities contribute to poly(A) pruning of active mRNPs. Evidence that the SARS-CoV-2 RNA virus targets PABP, LARP1, LARP 4 and LARP 4B to control mRNP activity is also briefly reviewed. Recent data suggests that LARP4 opposes deadenylation by stabilizing PABP on mRNA poly(A) tails. Other data suggest that LARP1 can protect mRNA from deadenylation. This is dependent on a PAM2 motif with unique characteristics present in its La-module. Thus, while nuclear La and LARP7 stabilize small RNAs with 3' oligo(U) from decay, LARP1 and LARP4 bind and protect mRNA 3' poly(A) tails from deadenylases through close contact with PABP.Abbreviations: 5'TOP: 5' terminal oligopyrimidine, LaM: La motif, LARP: La-related protein, LARP1: La-related protein 1, MLLE: mademoiselle, NTR: N-terminal region, PABP: cytoplasmic poly(A)-binding protein (PABPC1), Pol III: RNA polymerase III, PAM2: PABP-interacting motif 2, PB: processing body, RRM: RNA recognition motif, SG: stress granule.
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Affiliation(s)
- Sandy Mattijssen
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Guennadi Kozlov
- Department of Biochemistry & Centre for Structural Biology, McGill University, Montreal, Canada
| | | | - Kalle Gehring
- Department of Biochemistry & Centre for Structural Biology, McGill University, Montreal, Canada
| | - Richard J. Maraia
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
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15
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Al-Ashtal HA, Rubottom CM, Leeper TC, Berman AJ. The LARP1 La-Module recognizes both ends of TOP mRNAs. RNA Biol 2021; 18:248-258. [PMID: 31601159 PMCID: PMC7927982 DOI: 10.1080/15476286.2019.1669404] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/22/2019] [Accepted: 09/12/2019] [Indexed: 12/11/2022] Open
Abstract
La-Related Protein 1 (LARP1) is an RNA-binding protein that regulates the stability and translation of mRNAs encoding the translation machinery, including ribosomal proteins and translation factors. These mRNAs are characterized by a 5'-terminal oligopyrimidine (TOP) motif that coordinates their temporal and stoichiometric expression. While LARP1 represses TOP mRNA translation via the C-terminal DM15 region, the role of the N-terminal La-Module in the recognition and translational regulation of TOP mRNAs remains elusive. Herein we show that the LARP1 La-Module also binds TOP motifs, although in a cap-independent manner. We also demonstrate that it recognizes poly(A) RNA. Further, our data reveal that the LARP1 La-Module can simultaneously engage TOP motifs and poly(A) RNA. These results evoke an intriguing molecular mechanism whereby LARP1 could regulate translation and stabilization of TOP transcripts.
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Affiliation(s)
- Hiba A. Al-Ashtal
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Courtney M. Rubottom
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Thomas C. Leeper
- Department of Chemistry & Biochemistry, Kennesaw State University, Kennesaw, GA, USA
| | - Andrea J. Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
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16
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Mattijssen S, Kozlov G, Gaidamakov S, Ranjan A, Fonseca BD, Gehring K, Maraia RJ. The isolated La-module of LARP1 mediates 3' poly(A) protection and mRNA stabilization, dependent on its intrinsic PAM2 binding to PABPC1. RNA Biol 2021; 18:275-289. [PMID: 33292040 PMCID: PMC7928023 DOI: 10.1080/15476286.2020.1860376] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 11/25/2020] [Accepted: 12/01/2020] [Indexed: 12/18/2022] Open
Abstract
The protein domain arrangement known as the La-module, comprised of a La motif (LaM) followed by a linker and RNA recognition motif (RRM), is found in seven La-related proteins: LARP1, LARP1B, LARP3 (La protein), LARP4, LARP4B, LARP6, and LARP7 in humans. Several LARPs have been characterized for their distinct activity in a specific aspect of RNA metabolism. The La-modules vary among the LARPs in linker length and RRM subtype. The La-modules of La protein and LARP7 bind and protect nuclear RNAs with UUU-3' tails from degradation by 3' exonucleases. LARP4 is an mRNA poly(A) stabilization factor that binds poly(A) and the cytoplasmic poly(A)-binding protein PABPC1 (also known as PABP). LARP1 exhibits poly(A) length protection and mRNA stabilization similar to LARP4. Here, we show that these LARP1 activities are mediated by its La-module and dependent on a PAM2 motif that binds PABP. The isolated La-module of LARP1 is sufficient for PABP-dependent poly(A) length protection and mRNA stabilization in HEK293 cells. A point mutation in the PAM2 motif in the La-module impairs mRNA stabilization and PABP binding in vivo but does not impair oligo(A) RNA binding by the purified recombinant La-module in vitro. We characterize the unusual PAM2 sequence of LARP1 and show it may differentially affect stable and unstable mRNAs. The unique LARP1 La-module can function as an autonomous factor to confer poly(A) protection and stabilization to heterologous mRNAs.
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Affiliation(s)
- Sandy Mattijssen
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Guennadi Kozlov
- Department of Biochemistry & Centre for Structural Biology, McGill University, Montreal, Canada
| | - Sergei Gaidamakov
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Amitabh Ranjan
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | | | - Kalle Gehring
- Department of Biochemistry & Centre for Structural Biology, McGill University, Montreal, Canada
| | - Richard J. Maraia
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
- Commissioned Corps, U.S. Public Health Service, Rockville, MD, USA
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17
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Vandelli A, Monti M, Milanetti E, Armaos A, Rupert J, Zacco E, Bechara E, Delli Ponti R, Tartaglia GG. Structural analysis of SARS-CoV-2 genome and predictions of the human interactome. Nucleic Acids Res 2020. [PMID: 33068416 DOI: 10.1101/2020.03.28.013789] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
Specific elements of viral genomes regulate interactions within host cells. Here, we calculated the secondary structure content of >2000 coronaviruses and computed >100 000 human protein interactions with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The genomic regions display different degrees of conservation. SARS-CoV-2 domain encompassing nucleotides 22 500-23 000 is conserved both at the sequence and structural level. The regions upstream and downstream, however, vary significantly. This part of the viral sequence codes for the Spike S protein that interacts with the human receptor angiotensin-converting enzyme 2 (ACE2). Thus, variability of Spike S is connected to different levels of viral entry in human cells within the population. Our predictions indicate that the 5' end of SARS-CoV-2 is highly structured and interacts with several human proteins. The binding proteins are involved in viral RNA processing, include double-stranded RNA specific editases and ATP-dependent RNA-helicases and have strong propensity to form stress granules and phase-separated assemblies. We propose that these proteins, also implicated in viral infections such as HIV, are selectively recruited by SARS-CoV-2 genome to alter transcriptional and post-transcriptional regulation of host cells and to promote viral replication.
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Affiliation(s)
- Andrea Vandelli
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Systems Biology of Infection Lab, Department of Biochemistry and Molecular Biology, Biosciences Faculty, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain
| | - Michele Monti
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Edoardo Milanetti
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy
| | - Alexandros Armaos
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Jakob Rupert
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
- Department of Biology 'Charles Darwin', Sapienza University of Rome, P.le A. Moro 5, Rome 00185, Italy
| | - Elsa Zacco
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Elias Bechara
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Riccardo Delli Ponti
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Gian Gaetano Tartaglia
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
- Department of Biology 'Charles Darwin', Sapienza University of Rome, P.le A. Moro 5, Rome 00185, Italy
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), 23 Passeig Lluis Companys, 08010 Barcelona, Spain
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18
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Vandelli A, Monti M, Milanetti E, Armaos A, Rupert J, Zacco E, Bechara E, Delli Ponti R, Tartaglia G. Structural analysis of SARS-CoV-2 genome and predictions of the human interactome. Nucleic Acids Res 2020; 48:11270-11283. [PMID: 33068416 PMCID: PMC7672441 DOI: 10.1093/nar/gkaa864] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/15/2020] [Accepted: 09/25/2020] [Indexed: 12/17/2022] Open
Abstract
Specific elements of viral genomes regulate interactions within host cells. Here, we calculated the secondary structure content of >2000 coronaviruses and computed >100 000 human protein interactions with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The genomic regions display different degrees of conservation. SARS-CoV-2 domain encompassing nucleotides 22 500-23 000 is conserved both at the sequence and structural level. The regions upstream and downstream, however, vary significantly. This part of the viral sequence codes for the Spike S protein that interacts with the human receptor angiotensin-converting enzyme 2 (ACE2). Thus, variability of Spike S is connected to different levels of viral entry in human cells within the population. Our predictions indicate that the 5' end of SARS-CoV-2 is highly structured and interacts with several human proteins. The binding proteins are involved in viral RNA processing, include double-stranded RNA specific editases and ATP-dependent RNA-helicases and have strong propensity to form stress granules and phase-separated assemblies. We propose that these proteins, also implicated in viral infections such as HIV, are selectively recruited by SARS-CoV-2 genome to alter transcriptional and post-transcriptional regulation of host cells and to promote viral replication.
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Affiliation(s)
- Andrea Vandelli
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Systems Biology of Infection Lab, Department of Biochemistry and Molecular Biology, Biosciences Faculty, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain
| | - Michele Monti
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Edoardo Milanetti
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy
| | - Alexandros Armaos
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Jakob Rupert
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
- Department of Biology ‘Charles Darwin’, Sapienza University of Rome, P.le A. Moro 5, Rome 00185, Italy
| | - Elsa Zacco
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Elias Bechara
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
| | - Riccardo Delli Ponti
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Gian Gaetano Tartaglia
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain and Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Center for Human Technologies, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genoa, Italy
- Department of Biology ‘Charles Darwin’, Sapienza University of Rome, P.le A. Moro 5, Rome 00185, Italy
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), 23 Passeig Lluis Companys, 08010 Barcelona, Spain
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19
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Wang Y, Qi Y, Ji T, Tang B, Li X, Zheng P, Bai S. Circ_LARP4 regulates high glucose-induced cell proliferation, apoptosis, and fibrosis in mouse mesangial cells. Gene 2020; 765:145114. [PMID: 32891769 DOI: 10.1016/j.gene.2020.145114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/12/2020] [Accepted: 08/28/2020] [Indexed: 10/23/2022]
Abstract
The current study aimed to investigate the role and underlying mechanisms of circ_LARP4 in diabetic nephropathy (DN). Here, mouse mesangial cells (SV40-MES13) were cultured with 30 mM glucose to establish a DN cellular model. The qRT-PCR results indicated that circ_LARP4 expression was downregulated in the DN cellular model compared to that in the control cells. As determined by an MTT assay, circ_LARP4 overexpression via the circ_LARP4 overexpression (OE) plasmids inhibited the cell proliferation rate. As determined by an Annexin V/PI kit and flow cytometry, circ_LARP4 overexpression increased the cell apoptosis rate. As measured by Western blot, circ_LARP4 overexpression enhanced BAX expression but reduced Bcl-2 expression, also suggesting an enhancement of cell apoptosis. Moreover, regarding cell fibrosis, circ_LARP4 overexpression reduced the mRNA levels of fibrosis markers, including fibronectin, collagen I and collagen IV. Interestingly, miR-424 was found to be reduced in the DN cellular model after transfection with the circ_LARP4 OE plasmids. In addition, restoration of miR-424 expression with the miR-424 mimics reversed the negative effects of circ_LARP4 overexpression on cell proliferation and fibrosis. In conclusion, circ_LARP4 was lower in the DN cellular model than in normal cells, and circ_LARP4 overexpression resulted in decreased cell proliferation and cell fibrosis but increased cell apoptosis in the DN cellular model by sponging miR-424.
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Affiliation(s)
- Yakun Wang
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China
| | - Yinghui Qi
- Department of Nephrology, Shanghai Punan Hospital of Pudong New District. 279 Linyi Road, Pudong New District, Shanghai 200125, PR China
| | - Tingting Ji
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China
| | - Bo Tang
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China
| | - Xiaoying Li
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China
| | - Pengxi Zheng
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China
| | - Shoujun Bai
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University. 1158 Gongyuan East Road, Qingpu District, Shanghai 201700, PR China.
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20
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Crystal Structure of a Variant PAM2 Motif of LARP4B Bound to the MLLE Domain of PABPC1. Biomolecules 2020; 10:biom10060872. [PMID: 32517187 PMCID: PMC7356810 DOI: 10.3390/biom10060872] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/31/2020] [Accepted: 06/04/2020] [Indexed: 12/15/2022] Open
Abstract
Eukaryotic cells determine the protein output of their genetic program by regulating mRNA transcription, localization, translation and turnover rates. This regulation is accomplished by an ensemble of RNA-binding proteins (RBPs) that bind to any given mRNA, thus forming mRNPs. Poly(A) binding proteins (PABPs) are prominent members of virtually all mRNPs that possess poly(A) tails. They serve as multifunctional scaffolds, allowing the recruitment of diverse factors containing a poly(A)-interacting motif (PAM) into mRNPs. We present the crystal structure of the variant PAM motif (termed PAM2w) in the N-terminal part of the positive translation factor LARP4B, which binds to the MLLE domain of the poly(A) binding protein C1 cytoplasmic 1 (PABPC1). The structural analysis, along with mutational studies in vitro and in vivo, uncovered a new mode of interaction between PAM2 motifs and MLLE domains.
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21
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Wu X, Zhao W, Cui Q, Zhou Y. Computational screening of potential regulators for mRNA-protein expression level discrepancy. Biochem Biophys Res Commun 2020; 523:196-201. [DOI: 10.1016/j.bbrc.2019.12.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 12/10/2019] [Indexed: 01/05/2023]
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22
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Dock-Bregeon AC, Lewis KA, Conte MR. The La-related proteins: structures and interactions of a versatile superfamily of RNA-binding proteins. RNA Biol 2019; 18:178-193. [PMID: 31752575 DOI: 10.1080/15476286.2019.1695712] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The La-related proteins (LaRPs) are an ancient superfamily of RNA-binding proteins orchestrating the major fates of RNA, from processing and maturation to regulation of mRNA translation. LaRPs are instrumental in modulating complex assemblies where the RNA is bound, folded, processed, escorted and presented to the functional effectors often through recruitment of protein partners. This intricate web of protein-RNA and protein-protein interactions is enabled by the modular nature of the LaRPs, comprising several structured domains connected by flexible linkers, and other sequences lacking recognizable folded motifs. Recent structures, together with biochemical and biophysical studies, have provided insights into how each LaRP family has evolved unique mechanisms of RNA recognition, not only through the conserved RNA-binding unit, the La-module, but also mediated by other family-specific motifs. Furthermore, in a series of unexpected twists and turns, they have revealed that the dynamic and conformational interplay of multi-structured domains and disordered regions operate in unison to achieve RNA substrate discrimination. This review proposes a perspective of our current knowledge of the structure-function relationship of the LaRP superfamily.
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Affiliation(s)
| | - Karen A Lewis
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX, USA
| | - Maria R Conte
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
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23
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Mallam AL, Sae-Lee W, Schaub JM, Tu F, Battenhouse A, Jang YJ, Kim J, Wallingford JB, Finkelstein IJ, Marcotte EM, Drew K. Systematic Discovery of Endogenous Human Ribonucleoprotein Complexes. Cell Rep 2019; 29:1351-1368.e5. [PMID: 31665645 PMCID: PMC6873818 DOI: 10.1016/j.celrep.2019.09.060] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 08/30/2019] [Accepted: 09/18/2019] [Indexed: 12/16/2022] Open
Abstract
RNA-binding proteins (RBPs) play essential roles in biology and are frequently associated with human disease. Although recent studies have systematically identified individual RNA-binding proteins, their higher-order assembly into ribonucleoprotein (RNP) complexes has not been systematically investigated. Here, we describe a proteomics method for systematic identification of RNP complexes in human cells. We identify 1,428 protein complexes that associate with RNA, indicating that more than 20% of known human protein complexes contain RNA. To explore the role of RNA in the assembly of each complex, we identify complexes that dissociate, change composition, or form stable protein-only complexes in the absence of RNA. We use our method to systematically identify cell-type-specific RNA-associated proteins in mouse embryonic stem cells and finally, distribute our resource, rna.MAP, in an easy-to-use online interface (rna.proteincomplexes.org). Our system thus provides a methodology for explorations across human tissues, disease states, and throughout all domains of life.
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Affiliation(s)
- Anna L Mallam
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
| | - Wisath Sae-Lee
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Jeffrey M Schaub
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Fan Tu
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Anna Battenhouse
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Yu Jin Jang
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Jonghwan Kim
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - John B Wallingford
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Ilya J Finkelstein
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Edward M Marcotte
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
| | - Kevin Drew
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
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24
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Vinayak J, Marrella SA, Hussain RH, Rozenfeld L, Solomon K, Bayfield MA. Human La binds mRNAs through contacts to the poly(A) tail. Nucleic Acids Res 2019; 46:4228-4240. [PMID: 29447394 PMCID: PMC5934636 DOI: 10.1093/nar/gky090] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 01/31/2018] [Indexed: 12/31/2022] Open
Abstract
In addition to a role in the processing of nascent RNA polymerase III transcripts, La proteins are also associated with promoting cap-independent translation from the internal ribosome entry sites of numerous cellular and viral coding RNAs. La binding to RNA polymerase III transcripts via their common UUU-3’OH motif is well characterized, but the mechanism of La binding to coding RNAs is poorly understood. Using electromobility shift assays and cross-linking immunoprecipitation, we show that in addition to a sequence specific UUU-3’OH binding mode, human La exhibits a sequence specific and length dependent poly(A) binding mode. We demonstrate that this poly(A) binding mode uses the canonical nucleic acid interaction winged helix face of the eponymous La motif, previously shown to be vacant during uridylate binding. We also show that cytoplasmic, but not nuclear La, engages poly(A) RNA in human cells, that La entry into polysomes utilizes the poly(A) binding mode, and that La promotion of translation from the cyclin D1 internal ribosome entry site occurs in competition with cytoplasmic poly(A) binding protein (PABP). Our data are consistent with human La functioning in translation through contacts to the poly(A) tail.
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Affiliation(s)
- Jyotsna Vinayak
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
| | - Stefano A Marrella
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
| | - Rawaa H Hussain
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
| | - Leonid Rozenfeld
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
| | - Karine Solomon
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
| | - Mark A Bayfield
- Department of Biology, York University, 4700 Keele St., Life Science Building #327E, Toronto, ON M3J 1P3, Canada
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25
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Cruz-Gallardo I, Martino L, Kelly G, Atkinson R, Trotta R, De Tito S, Coleman P, Ahdash Z, Gu Y, Bui TTT, Conte MR. LARP4A recognizes polyA RNA via a novel binding mechanism mediated by disordered regions and involving the PAM2w motif, revealing interplay between PABP, LARP4A and mRNA. Nucleic Acids Res 2019; 47:4272-4291. [PMID: 30820564 PMCID: PMC6486636 DOI: 10.1093/nar/gkz144] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/15/2019] [Accepted: 02/19/2019] [Indexed: 11/22/2022] Open
Abstract
LARP4A belongs to the ancient RNA-binding protein superfamily of La-related proteins (LARPs). In humans, it acts mainly by stabilizing mRNAs, enhancing translation and controlling polyA lengths of heterologous mRNAs. These activities are known to implicate its association with mRNA, protein partners and translating ribosomes, albeit molecular details are missing. Here, we characterize the direct interaction between LARP4A, oligoA RNA and the MLLE domain of the PolyA-binding protein (PABP). Our study shows that LARP4A-oligoA association entails novel RNA recognition features involving the N-terminal region of the protein that exists in a semi-disordered state and lacks any recognizable RNA-binding motif. Against expectations, we show that the La module, the conserved RNA-binding unit across LARPs, is not the principal determinant for oligoA interaction, only contributing to binding to a limited degree. Furthermore, the variant PABP-interacting motif 2 (PAM2w) featured in the N-terminal region of LARP4A was found to be important for both RNA and PABP recognition, revealing a new role for this protein-protein binding motif. Our analysis demonstrates the mutual exclusive nature of the PAM2w-mediated interactions, thereby unveiling a tantalizing interplay between LARP4A, polyA and PABP.
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Affiliation(s)
- Isabel Cruz-Gallardo
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Luigi Martino
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Geoff Kelly
- MRC Biomedical NMR Centre, The Francis Crick Institute, London NW1 1AT, UK
| | - R Andrew Atkinson
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
- Centre for Biomolecular Spectroscopy, King’s College London, London SE1 1UL, UK
| | - Roberta Trotta
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Stefano De Tito
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Pierre Coleman
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Zainab Ahdash
- Department of Chemistry, King’s College London, London SE1 1DB, UK
| | - Yifei Gu
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
| | - Tam T T Bui
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
- Centre for Biomolecular Spectroscopy, King’s College London, London SE1 1UL, UK
| | - Maria R Conte
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 1UL, UK
- Centre for Biomolecular Spectroscopy, King’s College London, London SE1 1UL, UK
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26
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Crawford RA, Pavitt GD. Translational regulation in response to stress in Saccharomyces cerevisiae. Yeast 2018; 36:5-21. [PMID: 30019452 PMCID: PMC6492140 DOI: 10.1002/yea.3349] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/08/2018] [Accepted: 06/25/2018] [Indexed: 12/19/2022] Open
Abstract
The budding yeast Saccharomyces cerevisiae must dynamically alter the composition of its proteome in order to respond to diverse stresses. The reprogramming of gene expression during stress typically involves initial global repression of protein synthesis, accompanied by the activation of stress‐responsive mRNAs through both translational and transcriptional responses. The ability of specific mRNAs to counter the global translational repression is therefore crucial to the overall response to stress. Here we summarize the major repressive mechanisms and discuss mechanisms of translational activation in response to different stresses in S. cerevisiae. Taken together, a wide range of studies indicate that multiple elements act in concert to bring about appropriate translational responses. These include regulatory elements within mRNAs, altered mRNA interactions with RNA‐binding proteins and the specialization of ribosomes that each contribute towards regulating protein expression to suit the changing environmental conditions.
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Affiliation(s)
- Robert A Crawford
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Michael Smith Building, Dover Street, Manchester, M13 9PT, UK
| | - Graham D Pavitt
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Michael Smith Building, Dover Street, Manchester, M13 9PT, UK
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27
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Yoshikawa H, Larance M, Harney DJ, Sundaramoorthy R, Ly T, Owen-Hughes T, Lamond AI. Efficient analysis of mammalian polysomes in cells and tissues using Ribo Mega-SEC. eLife 2018; 7:36530. [PMID: 30095066 PMCID: PMC6086667 DOI: 10.7554/elife.36530] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/28/2018] [Indexed: 12/14/2022] Open
Abstract
We describe Ribo Mega-SEC, a powerful approach for the separation and biochemical analysis of mammalian polysomes and ribosomal subunits using Size Exclusion Chromatography and uHPLC. Using extracts from either cells, or tissues, polysomes can be separated within 15 min from sample injection to fraction collection. Ribo Mega-SEC shows translating ribosomes exist predominantly in polysome complexes in human cell lines and mouse liver tissue. Changes in polysomes are easily quantified between treatments, such as the cellular response to amino acid starvation. Ribo Mega-SEC is shown to provide an efficient, convenient and highly reproducible method for studying functional translation complexes. We show that Ribo Mega-SEC is readily combined with high-throughput MS-based proteomics to characterize proteins associated with polysomes and ribosomal subunits. It also facilitates isolation of complexes for electron microscopy and structural studies.
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Affiliation(s)
- Harunori Yoshikawa
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Mark Larance
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom.,Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Dylan J Harney
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | | | - Tony Ly
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom.,Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Tom Owen-Hughes
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Angus I Lamond
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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28
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Funakoshi M, Tsuda M, Muramatsu K, Hatsuda H, Morishita S, Aigaki T. Overexpression of Larp4B downregulates dMyc and reduces cell and organ sizes in Drosophila. Biochem Biophys Res Commun 2018; 497:762-768. [PMID: 29462618 DOI: 10.1016/j.bbrc.2018.02.148] [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: 02/13/2018] [Accepted: 02/17/2018] [Indexed: 11/27/2022]
Abstract
Regulation of cell and organ sizes is fundamental for all organisms, but its molecular basis is not fully understood. Here we performed a gain-of-function screen and identified larp4B whose overexpression reduces cell and organ sizes in Drosophila melanogaster. Larp4B is a member of La-related proteins (LARPs) containing an LA motif and an adjacent RNA recognition motif (RRM), and play diverse roles in RNA metabolism. However, the function of Larp4B has remained poorly characterized. We generated transgenic flies overexpressing wild-type Larp4B or a deletion variant lacking the LA and RRM domains, and demonstrated that the RNA-binding domains are essential for Larp4B to reduce cell and organ sizes. We found that the larp4B-induced phenotype was suppressed by dMyc overexpression, which promotes cell growth and survival. Furthermore, overexpression of larp4B decreased dMyc protein levels, whereas its loss-of-function mutation had an opposite effect. Our results suggest that Larp4B is a negative regulator of dMyc.
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Affiliation(s)
- Masabumi Funakoshi
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji-shi, Tokyo 192-0397, Japan
| | - Manabu Tsuda
- Department of Liberal Arts and Human Development, Kanagawa University of Human Services, 1-10-1, Heiseicho, Yokosuka-shi, Kanagawa 238-8522, Japan
| | - Keigo Muramatsu
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji-shi, Tokyo 192-0397, Japan
| | - Hiroshi Hatsuda
- Department of Computational Biology, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa 277-0882, Japan
| | - Shinichi Morishita
- Department of Computational Biology, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa 277-0882, Japan
| | - Toshiro Aigaki
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji-shi, Tokyo 192-0397, Japan.
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29
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Hasan M, Mustafa G, Iqbal J, Ashfaq M, Mahmood N. Quantitative proteomic analysis of HeLa cells in response to biocompatible Fe 2C@C nanoparticles: 16O/ 18O-labelling & HPLC-ESI-orbit-trap profiling approach. Toxicol Res (Camb) 2018; 7:84-92. [PMID: 30090565 PMCID: PMC6060731 DOI: 10.1039/c7tx00248c] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/07/2017] [Indexed: 11/21/2022] Open
Abstract
The effective detection of molecular biomarkers, such as proteins, lipids, carbohydrates, and pathogens, in a living body is a huge challenge in the field of nanomedicine. Here, we have investigated the comparative quantitative proteomics analysis of the molecular response of HeLa cells to biocompatible Fe2C@C nanoparticles (NPs) using 16O/18O isotopic labelling of the cell culture. The relative binding efficiency of proteins to Fe2C@C NPs was calculated. HPLC-ESI-orbit-trap analysis found 51 differentially expressed proteins, out of which 23 were over-expressed and 28 down-regulated. This study showed that Fe2C@C NPs alter the expression of the proteins involved in endocytosis, cell-cycle regulation, and cell membrane protrusion. Further, the quantification and validation of the mass spectrometry (MS) results was successfully confirmed by western blot analysis of cytochrome C. The change in the expression of proteins can be useful for early stage disease diagnoses and the development of tailored therapeutic strategies. This study is the first large-scale characterization of low abundance proteins on Fe2C@C NPs, providing the biochemical basis for the assessment of the suitability of magnetic NPs as biomedical markers and emerging functional probes.
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Affiliation(s)
- Murtaza Hasan
- Department of Biochemistry and Biotechnology , The Islamia University of Bahawalpur , Pakistan
- Department of Materials Science and Engineering , College of Engineering , Peking University , Beijing , 178001 , China
| | - Ghazala Mustafa
- Department of Plant Sciences , Quaid-i-Azam University , Islamabad 45320 , Pakistan
| | - Javed Iqbal
- College of Life Sciences , Shenzhen University , Shenzhen 10590 , China
| | - Muhammad Ashfaq
- Department of Biochemistry and Biotechnology , The Islamia University of Bahawalpur , Pakistan
| | - Nasir Mahmood
- School of Engineering , RMIT University , 124 La Trobe Street , 3001 Melbourne , Victoria , Australia . ; ; Tel: +61423669339
- Center of Micro-Nano Functional Materials and Devices , School of Energy Science and Engineering , State key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 611731 , China
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30
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Maraia RJ, Mattijssen S, Cruz-Gallardo I, Conte MR. The La and related RNA-binding proteins (LARPs): structures, functions, and evolving perspectives. WILEY INTERDISCIPLINARY REVIEWS. RNA 2017; 8:10.1002/wrna.1430. [PMID: 28782243 PMCID: PMC5647580 DOI: 10.1002/wrna.1430] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/12/2017] [Accepted: 05/15/2017] [Indexed: 01/02/2023]
Abstract
La was first identified as a polypeptide component of ribonucleic protein complexes targeted by antibodies in autoimmune patients and is now known to be a eukaryote cell-ubiquitous protein. Structure and function studies have shown that La binds to a common terminal motif, UUU-3'-OH, of nascent RNA polymerase III (RNAP III) transcripts and protects them from exonucleolytic decay. For precursor-tRNAs, the most diverse and abundant of these transcripts, La also functions as an RNA chaperone that helps to prevent their misfolding. Related to this, we review evidence that suggests that La and its link to RNAP III were significant in the great expansions of the tRNAomes that occurred in eukaryotes. Four families of La-related proteins (LARPs) emerged during eukaryotic evolution with specialized functions. We provide an overview of the high-resolution structural biology of La and LARPs. LARP7 family members most closely resemble La but function with a single RNAP III nuclear transcript, 7SK, or telomerase RNA. A cytoplasmic isoform of La protein as well as LARPs 6, 4, and 1 function in mRNA metabolism and translation in distinct but similar ways, sometimes with the poly(A)-binding protein, and in some cases by direct binding to poly(A)-RNA. New structures of LARP domains, some complexed with RNA, provide novel insights into the functional versatility of these proteins. We also consider LARPs in relation to ancestral La protein and potential retention of links to specific RNA-related pathways. One such link may be tRNA surveillance and codon usage by LARP-associated mRNAs. WIREs RNA 2017, 8:e1430. doi: 10.1002/wrna.1430 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Richard J. Maraia
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD USA
- Commissioned Corps, U.S. Public Health Service, Rockville, MD USA
| | - Sandy Mattijssen
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD USA
| | - Isabel Cruz-Gallardo
- Randall Division of Cell and Molecular Biophysics, King's College London, Guy's Campus, London, UK
| | - Maria R. Conte
- Randall Division of Cell and Molecular Biophysics, King's College London, Guy's Campus, London, UK
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31
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Mattijssen S, Arimbasseri AG, Iben JR, Gaidamakov S, Lee J, Hafner M, Maraia RJ. LARP4 mRNA codon-tRNA match contributes to LARP4 activity for ribosomal protein mRNA poly(A) tail length protection. eLife 2017; 6:e28889. [PMID: 28895529 PMCID: PMC5626478 DOI: 10.7554/elife.28889] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/05/2017] [Indexed: 12/12/2022] Open
Abstract
Messenger RNA function is controlled by the 3' poly(A) tail (PAT) and poly(A)-binding protein (PABP). La-related protein-4 (LARP4) binds poly(A) and PABP. LARP4 mRNA contains a translation-dependent, coding region determinant (CRD) of instability that limits its expression. Although the CRD comprises <10% of LARP4 codons, the mRNA levels vary >20 fold with synonymous CRD substitutions that accommodate tRNA dynamics. Separately, overexpression of the most limiting tRNA increases LARP4 levels and reveals its functional activity, net lengthening of the PATs of heterologous mRNAs with concomitant stabilization, including ribosomal protein (RP) mRNAs. Genetic deletion of cellular LARP4 decreases PAT length and RPmRNA stability. This LARP4 activity requires its PABP-interaction domain and the RNA-binding module which we show is sensitive to poly(A) 3'-termini, consistent with protection from deadenylation. The results indicate that LARP4 is a posttranscriptional regulator of ribosomal protein production in mammalian cells and suggest that this activity can be controlled by tRNA levels.
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Affiliation(s)
- Sandy Mattijssen
- Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUnited States
| | | | - James R Iben
- Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUnited States
| | - Sergei Gaidamakov
- Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUnited States
| | - Joowon Lee
- Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUnited States
| | - Markus Hafner
- National Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institutes of HealthBethesdaUnited States
| | - Richard J Maraia
- Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUnited States
- Commissioned CorpsUS Public Health ServiceBethesdaUnited Staes
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32
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Poluha A, Bernaciak J, Jaszczuk I, Kędzior M, Nowakowska BA. Molecular and clinical characterization of new patient with 1,08 Mb deletion in 10p15.3 region. Mol Cytogenet 2017; 10:34. [PMID: 28912834 PMCID: PMC5588601 DOI: 10.1186/s13039-017-0336-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 08/29/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Three distinct contiguous gene deletion syndromes are located at 10p chromosomal region. The deletion, involving 10p15.3 region, has been characterized by (DeScipio et al., Am J Med Genet A 158A:2152-61, 2012). However, because of the variation in size of the described deletions and lack of knowledge about the involved genes, the correlation between genotypes and patients' phenotypes remains unknown. CASE PRESENTATION We describe female patient with de novo 1,08 Mb deletion in 10p15.3 region, similar to the patient nr seven reported by (DeScipio et al., Am J Med Genet A 158A:2152-61, 2012) but with more severe clinical features. Our patient demonstrated speech and motor delay, dysmorphic features, brain abnormalities and Tetralogy of Fallot with pulmonary atresia. CONCLUSIONS This case shows the importance of collection of more patients with deletion in order to obtain a more precise physical map of 10p region.
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Affiliation(s)
- Anna Poluha
- Department of Pediatric Hematology, Oncology and Transplantation Children's University Hospital, Lublin, Poland
| | - Joanna Bernaciak
- Department of Medical Genetics, Cytogenetics, Institute of Mother and Child, Kasprzaka 17, A 01-211 Warsaw, Poland
| | - Ilona Jaszczuk
- Department of Pediatric Hematology, Oncology and Transplantation Children's University Hospital, Lublin, Poland
| | - Marta Kędzior
- Department of Medical Genetics, Cytogenetics, Institute of Mother and Child, Kasprzaka 17, A 01-211 Warsaw, Poland
| | - Beata Anna Nowakowska
- Department of Medical Genetics, Cytogenetics, Institute of Mother and Child, Kasprzaka 17, A 01-211 Warsaw, Poland
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33
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Seetharaman S, Flemyng E, Shen J, Conte MR, Ridley AJ. The RNA-binding protein LARP4 regulates cancer cell migration and invasion. Cytoskeleton (Hoboken) 2016; 73:680-690. [PMID: 27615744 PMCID: PMC5111583 DOI: 10.1002/cm.21336] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 01/07/2023]
Abstract
LARP4 is a La-related RNA-binding protein implicated in regulating mRNA translation, which interacts with poly(A)-binding protein (PABP). We previously identified LARP4 in an RNAi screen as one of several genes that regulate the shape of PC3 prostate cancer cells. Here we show that LARP4 depletion induces cell elongation in PC3 cells and MDA-MB-231 breast cancer cells. LARP4 depletion increases cell migration and invasion, as well as inducing invasive cell protrusions in 3D Matrigel. Conversely, LARP4 over-expression reduces cell elongation and increases cell circularity. LARP4 mutations are found in a variety of cancers. Introduction of some of these cancer-associated mutations, including a truncation mutant, into LARP4 enhances its effects on cell morphology. The truncation mutant shows enhanced interaction with PABP. We propose that LARP4 inhibits migration and invasion of cancer cells, and that some cancer-associated mutations stimulate these effects of LARP4. © 2016 The Authors. Cytoskeleton Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Shailaja Seetharaman
- Randall Division of Cell and Molecular BiophysicsKing's College LondonNew Hunt's House, Guy's CampusLondonSE1 1ULUnited Kingdom
| | - Ella Flemyng
- Randall Division of Cell and Molecular BiophysicsKing's College LondonNew Hunt's House, Guy's CampusLondonSE1 1ULUnited Kingdom
| | - Jiazhen Shen
- Randall Division of Cell and Molecular BiophysicsKing's College LondonNew Hunt's House, Guy's CampusLondonSE1 1ULUnited Kingdom
| | - Maria R. Conte
- Randall Division of Cell and Molecular BiophysicsKing's College LondonNew Hunt's House, Guy's CampusLondonSE1 1ULUnited Kingdom
| | - Anne J. Ridley
- Randall Division of Cell and Molecular BiophysicsKing's College LondonNew Hunt's House, Guy's CampusLondonSE1 1ULUnited Kingdom
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34
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Koso H, Yi H, Sheridan P, Miyano S, Ino Y, Todo T, Watanabe S. Identification of RNA-Binding Protein LARP4B as a Tumor Suppressor in Glioma. Cancer Res 2016; 76:2254-64. [PMID: 26933087 DOI: 10.1158/0008-5472.can-15-2308] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 02/17/2016] [Indexed: 11/16/2022]
Abstract
Transposon-based insertional mutagenesis is a valuable method for conducting unbiased forward genetic screens to identify cancer genes in mice. We used this system to elucidate factors involved in the malignant transformation of neural stem cells into glioma-initiating cells. We identified an RNA-binding protein, La-related protein 4b (LARP4B), as a candidate tumor-suppressor gene in glioma. LARP4B expression was consistently decreased in human glioma stem cells and cell lines compared with normal neural stem cells. Moreover, heterozygous deletion of LARP4B was detected in nearly 80% of glioblastomas in The Cancer Genome Atlas database. LARP4B loss was also associated with low expression and poor patient survival. Overexpression of LARP4B in glioma cell lines strongly inhibited proliferation by inducing mitotic arrest and apoptosis in four of six lines as well as in two patient-derived glioma stem cell populations. The expression levels of CDKN1A and BAX were also upregulated upon LARP4B overexpression, and the growth-inhibitory effects were partially dependent on p53 (TP53) activity in cells expressing wild-type, but not mutant, p53. We further found that the La module, which is responsible for the RNA chaperone activity of LARP4B, was important for the growth-suppressive effect and was associated with BAX mRNA. Finally, LARP4B depletion in p53 and Nf1-deficient mouse primary astrocytes promoted cell proliferation and led to increased tumor size and invasiveness in xenograft and orthotopic models. These data provide strong evidence that LARP4B serves as a tumor-suppressor gene in glioma, encouraging further exploration of the RNA targets potentially involved in LARP4B-mediatd growth inhibition. Cancer Res; 76(8); 2254-64. ©2016 AACR.
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Affiliation(s)
- Hideto Koso
- Division of Molecular and Developmental Biology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Hungtsung Yi
- Division of Molecular and Developmental Biology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Paul Sheridan
- Laboratory of DNA Information Analysis, Human Genome Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Satoru Miyano
- Laboratory of DNA Information Analysis, Human Genome Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yasushi Ino
- Division of Innovative Cancer Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Tomoki Todo
- Division of Innovative Cancer Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Sumiko Watanabe
- Division of Molecular and Developmental Biology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
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Mattijssen S, Maraia RJ. LARP4 Is Regulated by Tumor Necrosis Factor Alpha in a Tristetraprolin-Dependent Manner. Mol Cell Biol 2016; 36:574-84. [PMID: 26644407 PMCID: PMC4751689 DOI: 10.1128/mcb.00804-15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 09/14/2015] [Accepted: 11/20/2015] [Indexed: 01/09/2023] Open
Abstract
LARP4 is a protein with unknown function that independently binds to poly(A) RNA, RACK1, and the poly(A)-binding protein (PABPC1). Here, we report on its regulation. We found a conserved AU-rich element (ARE) in the human LARP4 mRNA 3' untranslated region (UTR). This ARE, but not its antisense version or a point-mutated version, significantly decreased the stability of β-globin reporter mRNA. We found that overexpression of tristetraprolin (TTP), but not its RNA binding mutant or the other ARE-binding proteins tested, decreased cellular LARP4 levels. RNA coimmunoprecipitation showed that TTP specifically associated with LARP4 mRNA in vivo. Consistent with this, mouse LARP4 accumulated to higher levels in TTP gene knockout (KO) cells than in control cells. Stimulation of WT cells with tumor necrosis factor alpha (TNF-α), which rapidly induces TTP, robustly decreased LARP4 with a coincident time course but had no such effect on LARP4B or La protein or on LARP4 in the TTP KO cells. The TNF-α-induced TTP pulse was followed by a transient decrease in LARP4 mRNA that was quickly followed by a subsequent transient decrease in LARP4 protein. Involvement of LARP4 as a target of TNF-α-TTP regulation provides a clue as to how its functional activity may be used in a physiologic pathway.
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Affiliation(s)
- Sandy Mattijssen
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Richard J Maraia
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA Commissioned Corps, U.S. Public Health Service, Washington, DC, USA
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Stavraka C, Blagden S. The La-Related Proteins, a Family with Connections to Cancer. Biomolecules 2015; 5:2701-22. [PMID: 26501340 PMCID: PMC4693254 DOI: 10.3390/biom5042701] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/21/2015] [Accepted: 10/07/2015] [Indexed: 01/09/2023] Open
Abstract
The evolutionarily-conserved La-related protein (LARP) family currently comprises Genuine La, LARP1, LARP1b, LARP4, LARP4b, LARP6 and LARP7. Emerging evidence suggests each LARP has a distinct role in transcription and/or mRNA translation that is attributable to subtle sequence variations within their La modules and specific C-terminal domains. As emerging research uncovers the function of each LARP, it is evident that La, LARP1, LARP6, LARP7 and possibly LARP4a and 4b are dysregulated in cancer. Of these, LARP1 is the first to be demonstrated to drive oncogenesis. Here, we review the role of each LARP and the evidence linking it to malignancy. We discuss a future strategy of targeting members of this protein family as cancer therapy.
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Affiliation(s)
- Chara Stavraka
- Ovarian Cancer Research Centre, Institute for Reproductive and Developmental Biology, Imperial College, Du Cane Road, London W12 0HS, UK.
| | - Sarah Blagden
- Ovarian Cancer Research Centre, Institute for Reproductive and Developmental Biology, Imperial College, Du Cane Road, London W12 0HS, UK.
- Department of Oncology, University of Oxford, Churchill Hospital, Old Road, Oxford OX3 7LE, UK.
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Küspert M, Murakawa Y, Schäffler K, Vanselow JT, Wolf E, Juranek S, Schlosser A, Landthaler M, Fischer U. LARP4B is an AU-rich sequence associated factor that promotes mRNA accumulation and translation. RNA (NEW YORK, N.Y.) 2015; 21:1294-305. [PMID: 26001795 PMCID: PMC4478348 DOI: 10.1261/rna.051441.115] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 04/02/2015] [Indexed: 05/23/2023]
Abstract
mRNAs are key molecules in gene expression and subject to diverse regulatory events. Regulation is accomplished by distinct sets of trans-acting factors that interact with mRNAs and form defined mRNA-protein complexes (mRNPs). The resulting "mRNP code" determines the fate of any given mRNA and thus controlling gene expression at the post-transcriptional level. The La-related protein 4B (LARP4B) belongs to an evolutionarily conserved family of RNA-binding proteins characterized by the presence of a La-module implicated in direct RNA binding. Biochemical experiments have shown previously direct interactions of LARP4B with factors of the translation machinery. This finding along with the observation of an association with actively translating ribosomes suggested that LARP4B is a factor contributing to the mRNP code. To gain insight into the function of LARP4B in vivo we tested its mRNA association at the transcriptome level and its impact on the proteome. PAR-CLIP analyses allowed us to identify the in vivo RNA targets of LARP4B. We show that LARP4B binds to a distinct set of cellular mRNAs by contacting their 3' UTRs. Biocomputational analysis combined with in vitro binding assays identified the LARP4B-binding motif on mRNA targets. The reduction of cellular LARP4B levels leads to a marked destabilization of its mRNA targets and consequently their reduced translation. Our data identify LARP4B as a component of the mRNP code that influences the expression of its mRNA targets by affecting their stability.
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Affiliation(s)
- Maritta Küspert
- Biozentrum Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | | | - Katrin Schäffler
- Biozentrum Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Jens T Vanselow
- Rudolf-Virchow-Zentrum für Experimentelle Biomedizin, Universität Würzburg, D-97080 Würzburg, Germany
| | - Elmar Wolf
- Biozentrum Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Stefan Juranek
- Biozentrum Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Andreas Schlosser
- Rudolf-Virchow-Zentrum für Experimentelle Biomedizin, Universität Würzburg, D-97080 Würzburg, Germany
| | | | - Utz Fischer
- Biozentrum Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany Rudolf-Virchow-Zentrum für Experimentelle Biomedizin, Universität Würzburg, D-97080 Würzburg, Germany Department of Radiation Medicine and Applied Sciences, University of California at San Diego, San Diego, California 92037, USA
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Zhang Y, Peng L, Hu T, Wan Y, Ren Y, Zhang J, Wang X, Zhou Y, Yuan W, Wang Q, Cheng T, Zhu X. La-related protein 4B maintains murine MLL-AF9 leukemia stem cell self-renewal by regulating cell cycle progression. Exp Hematol 2015; 43:309-18.e2. [PMID: 25534202 DOI: 10.1016/j.exphem.2014.12.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 12/08/2014] [Accepted: 12/10/2014] [Indexed: 12/19/2022]
Abstract
Our recent study identified a nonsense mutation of La-related protein 4B (LARP4B) from whole genome sequencing of a 3-year-old female monozygotic twin pair discordant for MLL-associated acute myeloid leukemia (AML). To study the role of LARP4B in AML, we established a LARP4B-knockdown MLL-AF9 AML mouse model. Using this mouse model, we found that LARP4B knockdown significantly decreased leukemia cells in the peripheral blood, spleen, and bone marrow and prolonged the survival of AML recipient mice. Additional studies showed that LARP4B knockdown reduced leukemia stem cells (LSCs) and impaired the self-renew capacity of LSCs. Cell cycle analysis revealed that LARP4B knockdown arrested more LSCs in the G0 phase. The transcription of the cell cycle inhibitors p16, p19, and p21 and of the lineage-specific transcription factor CCAAT-enhancer-binding protein α was increased in the LARP4B-knockdown LSCs. Thus, our results demonstrate that LARP4B plays an important role in the maintenance of LSCs and suggest that LARP4B may regulate the cell cycle of LSCs via suppressing the expression of the cell cycle inhibitors p16, p19, and p21 and the myeloid specific transcription factor CCAAT-enhancer-binding protein α.
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Affiliation(s)
- Yingchi Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Luyun Peng
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Tianyuan Hu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yang Wan
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuanyuan Ren
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Jingliao Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaojuan Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuan Zhou
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Weiping Yuan
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Qianfei Wang
- Laboratory of Genome Variations and Precision Bio-Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Tao Cheng
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaofan Zhu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing, China.
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Antonacci S, Forand D, Wolf M, Tyus C, Barney J, Kellogg L, Simon MA, Kerr G, Wells KL, Younes S, Mortimer NT, Olesnicky EC, Killian DJ. Conserved RNA-binding proteins required for dendrite morphogenesis in Caenorhabditis elegans sensory neurons. G3 (BETHESDA, MD.) 2015; 5:639-53. [PMID: 25673135 PMCID: PMC4390579 DOI: 10.1534/g3.115.017327] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/09/2015] [Indexed: 01/22/2023]
Abstract
The regulation of dendritic branching is critical for sensory reception, cell-cell communication within the nervous system, learning, memory, and behavior. Defects in dendrite morphology are associated with several neurologic disorders; thus, an understanding of the molecular mechanisms that govern dendrite morphogenesis is important. Recent investigations of dendrite morphogenesis have highlighted the importance of gene regulation at the posttranscriptional level. Because RNA-binding proteins mediate many posttranscriptional mechanisms, we decided to investigate the extent to which conserved RNA-binding proteins contribute to dendrite morphogenesis across phyla. Here we identify a core set of RNA-binding proteins that are important for dendrite morphogenesis in the PVD multidendritic sensory neuron in Caenorhabditis elegans. Homologs of each of these genes were previously identified as important in the Drosophila melanogaster dendritic arborization sensory neurons. Our results suggest that RNA processing, mRNA localization, mRNA stability, and translational control are all important mechanisms that contribute to dendrite morphogenesis, and we present a conserved set of RNA-binding proteins that regulate these processes in diverse animal species. Furthermore, homologs of these genes are expressed in the human brain, suggesting that these RNA-binding proteins are candidate regulators of dendrite development in humans.
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Affiliation(s)
- Simona Antonacci
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Daniel Forand
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Margaret Wolf
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Courtney Tyus
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Julia Barney
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Leah Kellogg
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Margo A Simon
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Genevieve Kerr
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Kristen L Wells
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Serena Younes
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Nathan T Mortimer
- Department of Biological Sciences, University of Denver, Denver, Colorado 80208
| | - Eugenia C Olesnicky
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Darrell J Killian
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
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40
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The yeast La related protein Slf1p is a key activator of translation during the oxidative stress response. PLoS Genet 2015; 11:e1004903. [PMID: 25569619 PMCID: PMC4287443 DOI: 10.1371/journal.pgen.1004903] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 11/19/2014] [Indexed: 12/22/2022] Open
Abstract
The mechanisms by which RNA-binding proteins control the translation of subsets of mRNAs are not yet clear. Slf1p and Sro9p are atypical-La motif containing proteins which are members of a superfamily of RNA-binding proteins conserved in eukaryotes. RIP-Seq analysis of these two yeast proteins identified overlapping and distinct sets of mRNA targets, including highly translated mRNAs such as those encoding ribosomal proteins. In paralell, transcriptome analysis of slf1Δ and sro9Δ mutant strains indicated altered gene expression in similar functional classes of mRNAs following loss of each factor. The loss of SLF1 had a greater impact on the transcriptome, and in particular, revealed changes in genes involved in the oxidative stress response. slf1Δ cells are more sensitive to oxidants and RIP-Seq analysis of oxidatively stressed cells enriched Slf1p targets encoding antioxidants and other proteins required for oxidant tolerance. To quantify these effects at the protein level, we used label-free mass spectrometry to compare the proteomes of wild-type and slf1Δ strains following oxidative stress. This analysis identified several proteins which are normally induced in response to hydrogen peroxide, but where this increase is attenuated in the slf1Δ mutant. Importantly, a significant number of the mRNAs encoding these targets were also identified as Slf1p-mRNA targets. We show that Slf1p remains associated with the few translating ribosomes following hydrogen peroxide stress and that Slf1p co-immunoprecipitates ribosomes and members of the eIF4E/eIF4G/Pab1p ‘closed loop’ complex suggesting that Slf1p interacts with actively translated mRNAs following stress. Finally, mutational analysis of SLF1 revealed a novel ribosome interacting domain in Slf1p, independent of its RNA binding La-motif. Together, our results indicate that Slf1p mediates a translational response to oxidative stress via mRNA-specific translational control. All organisms must respond to changes in their external environment such as exposure to different stresses. The availability of genome sequences and post-genomic technologies has enabled the analysis of these adaptive responses at the molecular level in terms of altered gene expression profiles. However, relatively few studies have focused on how cells regulate the translation of mRNA into protein in response to stress, despite its fundamental role in gene expression pathways. In this study, we show that a previously identified RNA-binding protein called Slf1p plays a major role in mRNA-specific regulation of translation during oxidative stress conditions and is necessary to promote the translation of stress-responsive mRNAs. This protein is a member of the so-called “La-related” family of proteins that have not been well characterized, although they are conserved throughout evolution. Exposure to oxidants is known to cause a general down-regulation of protein synthesis, although many stress response proteins are able to overcome this inhibition and increase their protein levels following stress by as yet unknown mechanisms. Our experiments offer one possible explanation, as they show that Slf1p plays a critical role in enhancing translation of many of these proteins, including many that are necessary for the cellular stress response.
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Hussain RH, Zawawi M, Bayfield MA. Conservation of RNA chaperone activity of the human La-related proteins 4, 6 and 7. Nucleic Acids Res 2013; 41:8715-25. [PMID: 23887937 PMCID: PMC3794603 DOI: 10.1093/nar/gkt649] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 06/28/2013] [Accepted: 07/03/2013] [Indexed: 12/22/2022] Open
Abstract
The La module is a conserved tandem arrangement of a La motif and RNA recognition motif whose function has been best characterized in genuine La proteins. The best-characterized substrates of La proteins are pre-tRNAs, and previous work using tRNA mediated suppression in Schizosaccharomyces pombe has demonstrated that yeast and human La enhance the maturation of these using two distinguishable activities: UUU-3'OH-dependent trailer binding/protection and a UUU-3'OH independent activity related to RNA chaperone function. The La module has also been identified in several conserved families of La-related proteins (LARPs) that engage other RNAs, but their mode of RNA binding and function(s) are not well understood. We demonstrate that the La modules of the human LARPs 4, 6 and 7 are also active in tRNA-mediated suppression, even in the absence of stable UUU-3'OH trailer protection. Rather, the capacity of these to enhance pre-tRNA maturation is associated with RNA chaperone function, which we demonstrate to be a conserved activity for each hLARP in vitro. Our work reveals insight into the mechanisms by which La module containing proteins discriminate RNA targets and demonstrates that RNA chaperone activity is a conserved function across representative members of the La motif-containing superfamily.
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Affiliation(s)
| | | | - Mark A. Bayfield
- Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
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Merret R, Martino L, Bousquet-Antonelli C, Fneich S, Descombin J, Billey É, Conte MR, Deragon JM. The association of a La module with the PABP-interacting motif PAM2 is a recurrent evolutionary process that led to the neofunctionalization of La-related proteins. RNA (NEW YORK, N.Y.) 2013; 19:36-50. [PMID: 23148093 PMCID: PMC3527725 DOI: 10.1261/rna.035469.112] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 10/12/2012] [Indexed: 05/27/2023]
Abstract
La-related proteins (LARPs) are largely uncharacterized factors, well conserved throughout evolution. Recent reports on the function of human LARP4 and LARP6 suggest that these proteins fulfill key functions in mRNA metabolism and/or translation. We report here a detailed evolutionary history of the LARP4 and 6 families in eukaryotes. Genes coding for LARP4 and 6 were duplicated in the common ancestor of the vertebrate lineage, but one LARP6 gene was subsequently lost in the common ancestor of the eutherian lineage. The LARP6 gene was also independently duplicated several times in the vascular plant lineage. We observed that vertebrate LARP4 and plant LARP6 duplication events were correlated with the acquisition of a PABP-interacting motif 2 (PAM2) and with a significant reorganization of their RNA-binding modules. Using isothermal titration calorimetry (ITC) and immunoprecipitation methods, we show that the two plant PAM2-containing LARP6s (LARP6b and c) can, indeed, interact with the major plant poly(A)-binding protein (PAB2), while the third plant LARP6 (LARP6a) is unable to do so. We also analyzed the RNA-binding properties and the subcellular localizations of the two types of plant LARP6 proteins and found that they display nonredundant characteristics. As a whole, our results support a model in which the acquisition by LARP4 and LARP6 of a PAM2 allowed their targeting to mRNA 3' UTRs and led to their neofunctionalization.
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Affiliation(s)
- Rémy Merret
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
| | - Luigi Martino
- Randall Division of Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, United Kingdom
| | - Cécile Bousquet-Antonelli
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
| | - Sara Fneich
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
| | - Julie Descombin
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
| | - Élodie Billey
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
| | - Maria R. Conte
- Randall Division of Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, United Kingdom
| | - Jean-Marc Deragon
- Université de Perpignan Via Domitia, UMR5096 LGDP, 66860 Perpignan Cedex, France
- CNRS, UMR5096 LGDP, 66860 Perpignan Cedex, France
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Tang J, Huang ZM, Chen YY, Zhang ZH, Liu GL, Zhang J. A novel inhibitor of human La protein with anti-HBV activity discovered by structure-based virtual screening and in vitro evaluation. PLoS One 2012; 7:e36363. [PMID: 22558448 PMCID: PMC3338670 DOI: 10.1371/journal.pone.0036363] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 04/05/2012] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Over 350 million people worldwide are infected with hepatitis B virus (HBV), a major cause of liver failure and hepatocellular carcinoma. Current therapeutic agents are highly effective, but are also associated with development of viral resistance. Therefore, strategies for identifying other anti-HBV agents with specific, but distinctive mechanisms of action are needed. The human La (hLa) protein, which forms a stabilizing complex with HBV RNA ribonucleoprotein to promote HBV replication, is a promising target of molecular therapy. AIMS This study aimed to discover novel inhibitors of hLa that could inhibit HBV replication and expression. METHODS A multistage molecular docking approach was used to screen a Specs database and an in-house library against hLa binding sites. Sequential in vitro evaluations were performed to detect potential compounds with high scores in HepG2.2.15 cells. RESULTS Of the 26 potential compounds with high scores chosen for experimental verification, 12 had HBV DNA inhibition ratios of less than 50% with P<0.05. Six had significant inhibition of HBV e antigen (HBeAg) levels, and 13 had significant inhibition of HBV surface antigen (HBsAg) levels by in vitro assays. Compounds HBSC-11, HBSC-15 and HBSC-34 (HBSC is system prefix for active compounds screened by the library) were selected for evaluation. HBSC-11 was found to have an obvious inhibitory effect on hLa transcription and expression. CONCLUSIONS Our findings suggest that anti-HBV activity of HBSC-11 may be mediated by a reduction in hLa levels. In addition, our data suggest the potential clinical use of hLa inhibitors, such as HBSC-11, for treating HBV infection.
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Affiliation(s)
- Jing Tang
- Department of Pharmacy, First People's Hospital Affiliated with Shanghai JiaoTong University, Shanghai, China
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Schenk L, Meinel DM, Strässer K, Gerber AP. La-motif-dependent mRNA association with Slf1 promotes copper detoxification in yeast. RNA (NEW YORK, N.Y.) 2012; 18:449-61. [PMID: 22271760 PMCID: PMC3285933 DOI: 10.1261/rna.028506.111] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 11/25/2011] [Indexed: 05/31/2023]
Abstract
The La-motif (LAM) is an ancient and ubiquitous RNA-binding domain defining a superfamily of proteins, which comprises the genuine La proteins and La-related proteins (LARPs). In contrast to La, which binds and stabilizes pre-tRNAs and other RNA polymerase III transcripts, data on function and RNA targets of the LARPs have remained scarce. We have undertaken a global approach to elucidate the previously suggested role of the yeast LARP Slf1p in copper homeostasis. By applying RNA-binding protein immunopurification-microarray (RIP-Chip) analysis, we show that Slf1p and its paralog Sro9p copurify with overlapping sets of hundreds of functionally related mRNAs, including many transcripts coding for ribosomal proteins and histones. Interestingly, among these potential RNA targets were also mRNAs coding for proteins critical for protection of cells against elevated copper concentrations. Mutations introduced in the conserved aromatic patch of the LAM in Slf1p drastically impaired both association with its targets and Slf1-mediated protection of cells against toxic copper concentrations. Furthermore, we show that Slf1p stabilizes copper-related mRNA targets in a LAM-dependent manner. These results provide the first evidence for post-transcriptional regulation of factors/pathways implicated in copper homeostasis by a cytoplasmic RBP.
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Affiliation(s)
- Luca Schenk
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Dominik M. Meinel
- Department of Biochemistry, Gene Center and Center for Integrated Protein Science Munich (CIPSM), University of Munich, 81377 Munich, Germany
| | - Katja Strässer
- Department of Biochemistry, Gene Center and Center for Integrated Protein Science Munich (CIPSM), University of Munich, 81377 Munich, Germany
| | - André P. Gerber
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, 8093 Zurich, Switzerland
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Singh N, Morlock H, Hanes SD. The Bin3 RNA methyltransferase is required for repression of caudal translation in the Drosophila embryo. Dev Biol 2011; 352:104-15. [DOI: 10.1016/j.ydbio.2011.01.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2010] [Revised: 01/06/2011] [Accepted: 01/14/2011] [Indexed: 10/18/2022]
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Yang R, Gaidamakov SA, Xie J, Lee J, Martino L, Kozlov G, Crawford AK, Russo AN, Conte MR, Gehring K, Maraia RJ. La-related protein 4 binds poly(A), interacts with the poly(A)-binding protein MLLE domain via a variant PAM2w motif, and can promote mRNA stability. Mol Cell Biol 2011; 31:542-56. [PMID: 21098120 PMCID: PMC3028612 DOI: 10.1128/mcb.01162-10] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 11/05/2010] [Accepted: 11/12/2010] [Indexed: 12/19/2022] Open
Abstract
The conserved RNA binding protein La recognizes UUU-3'OH on its small nuclear RNA ligands and stabilizes them against 3'-end-mediated decay. We report that newly described La-related protein 4 (LARP4) is a factor that can bind poly(A) RNA and interact with poly(A) binding protein (PABP). Yeast two-hybrid analysis and reciprocal immunoprecipitations (IPs) from HeLa cells revealed that LARP4 interacts with RACK1, a 40S ribosome- and mRNA-associated protein. LARP4 cosediments with 40S ribosome subunits and polyribosomes, and its knockdown decreases translation. Mutagenesis of the RNA binding or PABP interaction motifs decrease LARP4 association with polysomes. Several translation and mRNA metabolism-related proteins use a PAM2 sequence containing a critical invariant phenylalanine to make direct contact with the MLLE domain of PABP, and their competition for the MLLE is thought to regulate mRNA homeostasis. Unlike all ∼150 previously analyzed PAM2 sequences, LARP4 contains a variant PAM2 (PAM2w) with tryptophan in place of the phenylalanine. Binding and nuclear magnetic resonance (NMR) studies have shown that a peptide representing LARP4 PAM2w interacts with the MLLE of PABP within the affinity range measured for other PAM2 motif peptides. A cocrystal of PABC bound to LARP4 PAM2w shows tryptophan in the pocket in PABC-MLLE otherwise occupied by phenylalanine. We present evidence that LARP4 expression stimulates luciferase reporter activity by promoting mRNA stability, as shown by mRNA decay analysis of luciferase and cellular mRNAs. We propose that LARP4 activity is integrated with other PAM2 protein activities by PABP as part of mRNA homeostasis.
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Affiliation(s)
- Ruiqing Yang
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Sergei A. Gaidamakov
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Jingwei Xie
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Joowon Lee
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Luigi Martino
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Guennadi Kozlov
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Amanda K. Crawford
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Amy N. Russo
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Maria R. Conte
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Kalle Gehring
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
| | - Richard J. Maraia
- Intramural Research Program on Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom, Department of Biochemistry, McGill University, Montreal, QC, Canada, Commissioned Corps, U.S. Public Health Service, Washington, DC
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