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Chadwick BJ, Ristow LC, Xie X, Krysan DJ, Lin X. Discovery of CO 2 tolerance genes associated with virulence in the fungal pathogen Cryptococcus neoformans. Nat Microbiol 2024:10.1038/s41564-024-01792-w. [PMID: 39232204 DOI: 10.1038/s41564-024-01792-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 07/23/2024] [Indexed: 09/06/2024]
Abstract
Cryptococcus neoformans is a ubiquitous soil fungus and airborne pathogen that causes over 180,000 deaths each year. Cryptococcus must adapt to host CO2 levels to cause disease, but the genetic basis for this adaptation is unknown. We utilized quantitative trait loci mapping with 374 progeny from a cross between a CO2-tolerant clinical isolate and a CO2-sensitive environmental isolate to identify genetic regions regulating CO2 tolerance. To identify specific quantitative trait genes, we applied fine mapping through bulk segregant analysis of near-isogenic progeny with distinct tolerance levels to CO2. We found that virulence among near-isogenic strains in a murine model of cryptococcosis correlated with CO2 tolerance. Moreover, we discovered that sensitive strains may adapt in vivo to become more CO2 tolerant and more virulent. These findings highlight the underappreciated role of CO2 tolerance and its importance in the ability of an opportunistic environmental pathogen to cause disease.
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Affiliation(s)
| | - Laura C Ristow
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Xiaofeng Xie
- Department of Microbiology, University of Georgia, Athens, GA, USA
| | - Damian J Krysan
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Xiaorong Lin
- Department of Plant Biology, University of Georgia, Athens, GA, USA.
- Department of Microbiology, University of Georgia, Athens, GA, USA.
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2
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Leikina E, Whitlock JM, Melikov K, Zhang W, Bachmann MP, Chernomordik LV. FORMATION OF MULTINUCLEATED OSTEOCLASTS DEPENDS ON AN OXIDIZED SPECIES OF CELL SURFACE ASSOCIATED LA PROTEIN. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.02.592254. [PMID: 38903088 PMCID: PMC11188106 DOI: 10.1101/2024.05.02.592254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
The bone-resorbing activity of osteoclasts plays a critical role in the life-long remodeling of our bones that is perturbed in many bone loss diseases. Multinucleated osteoclasts are formed by the fusion of precursor cells, and larger cells - generated by an increased number of cell fusion events - have higher resorptive activity. We find that osteoclast fusion and bone-resorption are promoted by reactive oxygen species (ROS) signaling and by an unconventional low molecular weight species of La protein, located at the osteoclast surface. Here, we develop the hypothesis that La's unique regulatory role in osteoclast multinucleation and function is controlled by a ROS switch in La trafficking. Using antibodies that recognize reduced or oxidized species of La, we find that differentiating osteoclasts enrich an oxidized species of La at the cell surface, which is distinct from the reduced La species conventionally localized within cell nuclei. ROS signaling triggers the shift from reduced to oxidized La species, its dephosphorylation and delivery to the surface of osteoclasts, where La promotes multinucleation and resorptive activity. Moreover, intracellular ROS signaling in differentiating osteoclasts oxidizes critical cysteine residues in the C-terminal half of La, producing this unconventional La species that promotes osteoclast fusion. Our findings suggest that redox signaling induces changes in the location and function of La and may represent a promising target for novel skeletal therapies.
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Affiliation(s)
- Evgenia Leikina
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jarred M. Whitlock
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kamran Melikov
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wendy Zhang
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael P. Bachmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany
- University Cancer Center (UCC), Tumor Immunology, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany
| | - Leonid V. Chernomordik
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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3
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Suwakulsiri W, Xu R, Rai A, Chen M, Shafiq A, Greening DW, Simpson RJ. Transcriptomic analysis and fusion gene identifications of midbody remnants released from colorectal cancer cells reveals they are molecularly distinct from exosomes and microparticles. Proteomics 2024; 24:e2300058. [PMID: 38470197 DOI: 10.1002/pmic.202300058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 02/25/2024] [Accepted: 02/27/2024] [Indexed: 03/13/2024]
Abstract
Previously, we reported that human primary (SW480) and metastatic (SW620) colorectal (CRC) cells release three classes of membrane-encapsulated extracellular vesicles (EVs); midbody remnants (MBRs), exosomes (Exos), and microparticles (MPs). We reported that MBRs were molecularly distinct at the protein level. To gain further biochemical insights into MBRs, Exos, and MPs and their emerging role in CRC, we performed, and report here, for the first time, a comprehensive transcriptome and long noncoding RNA sequencing analysis and fusion gene identification of these three EV classes using the next-generation RNA sequencing technique. Differential transcript expression analysis revealed that MBRs have a distinct transcriptomic profile compared to Exos and MPs with a high enrichment of mitochondrial transcripts lncRNA/pseudogene transcripts that are predicted to bind to ribonucleoprotein complexes, spliceosome, and RNA/stress granule proteins. A salient finding from this study is a high enrichment of several fusion genes in MBRs compared to Exos, MPs, and cell lysates from their parental cells such as MSH2 (gene encoded DNA mismatch repair protein MSH2). This suggests potential EV-liquid biopsy targets for cancer detection. Importantly, the expression of cancer progression-related transcripts found in EV classes derived from SW480 (EGFR) and SW620 (MET and MACCA1) cell lines reflects their parental cell types. Our study is the report of RNA and fusion gene compositions within MBRs (including Exos and MPs) that could have an impact on EV functionality in cancer progression and detection using EV-based RNA/ fusion gene candidates for cancer biomarkers.
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Affiliation(s)
- Wittaya Suwakulsiri
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science (LIMS), School of Agriculture, Biomedicine and Environment, La Trobe University, Melbourne, Victoria, Australia
- School of Biomedical Engineering, Faculty of Engineering, The University of Sydney, Darlington, New South Wales, Australia
| | - Rong Xu
- Nanobiotechnology Laboratory, Australia Centre for Blood Diseases, Centre Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Alin Rai
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Baker Department of Cardiovascular Research, Translation and Implementation, La Trobe University, Melbourne, Victoria, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Maoshan Chen
- Laboratory of Radiation Biology, Department of Blood Transfusion, Laboratory Medicine Centre, The Second Affiliated Hospital, Army Medical University, Chongqing, China
| | - Adnan Shafiq
- Department of Cell & Developmental Biology, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - David W Greening
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Baker Department of Cardiovascular Research, Translation and Implementation, La Trobe University, Melbourne, Victoria, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Richard J Simpson
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science (LIMS), School of Agriculture, Biomedicine and Environment, La Trobe University, Melbourne, Victoria, Australia
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4
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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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5
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Xiang X, Deng Q, Zheng Y, He Y, Ji D, Vejlupkova Z, Fowler JE, Zhou L. Genome-wide investigation of the LARP gene family: focus on functional identification and transcriptome profiling of ZmLARP6c1 in maize pollen. BMC PLANT BIOLOGY 2024; 24:348. [PMID: 38684961 PMCID: PMC11057080 DOI: 10.1186/s12870-024-05054-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 04/19/2024] [Indexed: 05/02/2024]
Abstract
BACKGROUND The La-related proteins (LARPs) are a superfamily of RNA-binding proteins associated with regulation of gene expression. Evidence points to an important role for post-transcriptional control of gene expression in germinating pollen tubes, which could be aided by RNA-binding proteins. RESULTS In this study, a genome-wide investigation of the LARP proteins in eight plant species was performed. The LARP proteins were classified into three families based on a phylogenetic analysis. The gene structure, conserved motifs, cis-acting elements in the promoter, and gene expression profiles were investigated to provide a comprehensive overview of the evolutionary history and potential functions of ZmLARP genes in maize. Moreover, ZmLARP6c1 was specifically expressed in pollen and ZmLARP6c1 was localized to the nucleus and cytoplasm in maize protoplasts. Overexpression of ZmLARP6c1 enhanced the percentage pollen germination compared with that of wild-type pollen. In addition, transcriptome profiling analysis revealed that differentially expressed genes included PABP homologous genes and genes involved in jasmonic acid and abscisic acid biosynthesis, metabolism, signaling pathways and response in a Zmlarp6c1::Ds mutant and ZmLARP6c1-overexpression line compared with the corresponding wild type. CONCLUSIONS The findings provide a basis for further evolutionary and functional analyses, and provide insight into the critical regulatory function of ZmLARP6c1 in maize pollen germination.
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Affiliation(s)
- Xiaoqin Xiang
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China
| | - Qianxia Deng
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China
| | - Yi Zheng
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China
| | - Yi He
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China
| | - Dongpu Ji
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China
| | - Zuzana Vejlupkova
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA
| | - John E Fowler
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA
| | - Lian Zhou
- College of Agronomy and Biotechnology, Maize Research Institute, Southwest University, Beibei, Chongqing, 400715, China.
- Engineering Research Center of South Upland Agriculture, Ministry of Education, Chongqing, 400715, China.
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6
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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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7
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Lewis BM, Cho CY, Her HL, Mizrahi O, Hunter T, Yeo GW. LARP4 is an RNA-binding protein that binds nuclear-encoded mitochondrial mRNAs to promote mitochondrial function. RNA (NEW YORK, N.Y.) 2024; 30:223-239. [PMID: 38164626 PMCID: PMC10870378 DOI: 10.1261/rna.079799.123] [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: 08/11/2023] [Accepted: 11/25/2023] [Indexed: 01/03/2024]
Abstract
Mitochondria-associated RNA-binding proteins (RBPs) have emerged as key contributors to mitochondrial biogenesis and homeostasis. With few examples known, we set out to identify RBPs that regulate nuclear-encoded mitochondrial mRNAs (NEMmRNAs). Our systematic analysis of RNA targets of 150 RBPs identified RBPs with a preference for binding NEMmRNAs, including LARP4, a La RBP family member. We show that LARP4's targets are particularly enriched in mRNAs that encode respiratory chain complex proteins (RCCPs) and mitochondrial ribosome proteins (MRPs) across multiple human cell lines. Through quantitative proteomics, we demonstrate that depletion of LARP4 leads to a significant reduction in RCCP and MRP protein levels. Furthermore, we show that LARP4 depletion reduces mitochondrial function, and that LARP4 re-expression rescues this phenotype. Our findings shed light on a novel function for LARP4 as an RBP that binds to and positively regulates NEMmRNAs to promote mitochondrial respiratory function.
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Affiliation(s)
- Benjamin M Lewis
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92037, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92037, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92037, USA
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Chae Yun Cho
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Hsuan-Lin Her
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92037, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92037, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92037, USA
- Bioinformatics and Systems Biology Graduate Program, University of California San Diego, La Jolla, California 92037, USA
| | - Orel Mizrahi
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92037, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92037, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92037, USA
| | - Tony Hunter
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92037, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92037, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92037, USA
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8
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Hochstoeger T, Chao JA. Towards a molecular understanding of the 5'TOP motif in regulating translation of ribosomal mRNAs. Semin Cell Dev Biol 2024; 154:99-104. [PMID: 37316417 DOI: 10.1016/j.semcdb.2023.06.001] [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: 05/20/2022] [Revised: 04/14/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
Vertebrate cells have evolved a simple, yet elegant, mechanism for coordinated regulation of ribosome biogenesis mediated by the 5' terminal oligopyrimidine motif (5'TOP). This motif allows cells to rapidly adapt to changes in the environment by specifically modulating translation rate of mRNAs encoding the translation machinery. Here, we provide an overview of the origin of this motif, its characterization, and progress in identifying the key regulatory factors involved. We highlight challenges in the field of 5'TOP research, and discuss future approaches that we think will be able to resolve outstanding questions.
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Affiliation(s)
- Tobias Hochstoeger
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland; University of Basel, 4003 Basel, Switzerland
| | - Jeffrey A Chao
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland.
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9
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Mattijssen S, Kerkhofs K, Stephen J, Yang A, Han CG, Tadafumi Y, Iben JR, Mishra S, Sakhawala RM, Ranjan A, Gowda M, Gahl WA, Gu S, Malicdan MC, Maraia RJ. A POLR3B-variant reveals a Pol III transcriptome response dependent on La protein/SSB. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.577363. [PMID: 38410490 PMCID: PMC10896340 DOI: 10.1101/2024.02.05.577363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
RNA polymerase III (Pol III, POLR3) synthesizes tRNAs and other small non-coding RNAs. Human POLR3 pathogenic variants cause a range of developmental disorders, recapitulated in part by mouse models, yet some aspects of POLR3 deficiency have not been explored. We characterized a human POLR3B:c.1625A>G;p.(Asn542Ser) disease variant that was found to cause mis-splicing of POLR3B. Genome-edited POLR3B1625A>G HEK293 cells acquired the mis-splicing with decreases in multiple POLR3 subunits and TFIIIB, although display auto-upregulation of the Pol III termination-reinitiation subunit POLR3E. La protein was increased relative to its abundant pre-tRNA ligands which bind via their U(n)U-3'-termini. Assays for cellular transcription revealed greater deficiencies for tRNA genes bearing terminators comprised of 4Ts than of ≥5Ts. La-knockdown decreased Pol III ncRNA expression unlinked to RNA stability. Consistent with these effects, small-RNAseq showed that POLR3B1625A>G and patient fibroblasts express more tRNA fragments (tRFs) derived from pre-tRNA 3'-trailers (tRF-1) than from mature-tRFs, and higher levels of multiple miRNAs, relative to control cells. The data indicate that decreased levels of Pol III transcripts can lead to functional excess of La protein which reshapes small ncRNA profiles revealing new depth in the Pol III system. Finally, patient cell RNA analysis uncovered a strategy for tRF-1/tRF-3 as POLR3-deficiency biomarkers.
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Affiliation(s)
- Sandy Mattijssen
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Kyra Kerkhofs
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Joshi Stephen
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
| | - Acong Yang
- RNA Biology Laboratory, National Cancer Institute, Frederick, MD, 21702 USA
| | - Chen G. Han
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
| | - Yokoyama Tadafumi
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
| | - James R. Iben
- Molecular Genetics Core, NICHD, NIH, Bethesda, MD 20892, USA
| | - Saurabh Mishra
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Rima M. Sakhawala
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Amitabh Ranjan
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Mamatha Gowda
- Department of Obstetrics & Gynaecology, Jawaharlal Institute of Post-Graduate Medical Education and Research, Puducherry, India
| | - William A. Gahl
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
- NIH Undiagnosed Diseases Program, NIH, Bethesda, MD 20892, USA
| | - Shuo Gu
- RNA Biology Laboratory, National Cancer Institute, Frederick, MD, 21702 USA
| | - May C. Malicdan
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892, USA
- NIH Undiagnosed Diseases Program, NIH, Bethesda, MD 20892, USA
| | - Richard J. Maraia
- Section on Molecular and Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
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10
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Tao Y, Zhang Q, Wang H, Yang X, Mu H. Alternative splicing and related RNA binding proteins in human health and disease. Signal Transduct Target Ther 2024; 9:26. [PMID: 38302461 PMCID: PMC10835012 DOI: 10.1038/s41392-024-01734-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 12/18/2023] [Accepted: 12/27/2023] [Indexed: 02/03/2024] Open
Abstract
Alternative splicing (AS) serves as a pivotal mechanism in transcriptional regulation, engendering transcript diversity, and modifications in protein structure and functionality. Across varying tissues, developmental stages, or under specific conditions, AS gives rise to distinct splice isoforms. This implies that these isoforms possess unique temporal and spatial roles, thereby associating AS with standard biological activities and diseases. Among these, AS-related RNA-binding proteins (RBPs) play an instrumental role in regulating alternative splicing events. Under physiological conditions, the diversity of proteins mediated by AS influences the structure, function, interaction, and localization of proteins, thereby participating in the differentiation and development of an array of tissues and organs. Under pathological conditions, alterations in AS are linked with various diseases, particularly cancer. These changes can lead to modifications in gene splicing patterns, culminating in changes or loss of protein functionality. For instance, in cancer, abnormalities in AS and RBPs may result in aberrant expression of cancer-associated genes, thereby promoting the onset and progression of tumors. AS and RBPs are also associated with numerous neurodegenerative diseases and autoimmune diseases. Consequently, the study of AS across different tissues holds significant value. This review provides a detailed account of the recent advancements in the study of alternative splicing and AS-related RNA-binding proteins in tissue development and diseases, which aids in deepening the understanding of gene expression complexity and offers new insights and methodologies for precision medicine.
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Affiliation(s)
- Yining Tao
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Qi Zhang
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
| | - Haoyu Wang
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Xiyu Yang
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Haoran Mu
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China.
- Shanghai Bone Tumor Institution, 200000, Shanghai, China.
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11
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Podszywalow-Bartnicka P, Neugebauer KM. Multiple roles for AU-rich RNA binding proteins in the development of haematologic malignancies and their resistance to chemotherapy. RNA Biol 2024; 21:1-17. [PMID: 38798162 PMCID: PMC11135835 DOI: 10.1080/15476286.2024.2346688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2024] [Indexed: 05/29/2024] Open
Abstract
Post-transcriptional regulation by RNA binding proteins can determine gene expression levels and drive changes in cancer cell proteomes. Identifying mechanisms of protein-RNA binding, including preferred sequence motifs bound in vivo, provides insights into protein-RNA networks and how they impact mRNA structure, function, and stability. In this review, we will focus on proteins that bind to AU-rich elements (AREs) in nascent or mature mRNA where they play roles in response to stresses encountered by cancer cells. ARE-binding proteins (ARE-BPs) specifically impact alternative splicing, stability, decay and translation, and formation of RNA-rich biomolecular condensates like cytoplasmic stress granules (SGs). For example, recent findings highlight the role of ARE-BPs - like TIAR and HUR - in chemotherapy resistance and in translational regulation of mRNAs encoding pro-inflammatory cytokines. We will discuss emerging evidence that different modes of ARE-BP activity impact leukaemia and lymphoma development, progression, adaptation to microenvironment and chemotherapy resistance.
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Affiliation(s)
- Paulina Podszywalow-Bartnicka
- Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, New Haven, CT, USA
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Karla M. Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, New Haven, CT, USA
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12
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Kozlov G, Jiang J, Rutherford T, Noronha AM, Wilds CJ, Gehring K. Enhanced binding of guanylated poly(A) RNA by the LaM domain of LARP1. RNA Biol 2024; 21:7-16. [PMID: 39016322 PMCID: PMC11259064 DOI: 10.1080/15476286.2024.2379121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2024] [Indexed: 07/18/2024] Open
Abstract
La-related proteins (LARPs) are a family of RNA-binding proteins that share a conserved La motif (LaM) domain. LARP1 plays a role in regulating ribosomal protein synthesis and stabilizing mRNAs and has a unique structure without an RNA binding RRM domain adjoining the LaM domain. In this study, we investigated the physical basis for LARP1 specificity for poly(A) sequences and observed an unexpected bias for sequences with single guanines. Multiple guanine substitutions did not increase the affinity, demonstrating preferential recognition of singly guanylated sequences. We also observed that the cyclic di-nucleotides in the cCAS/STING pathway, cyclic-di-GMP and 3',3'-cGAMP, bound with sub-micromolar affinity. Isothermal titration measurements were complemented by high-resolution crystal structures of the LARP1 LaM with six different RNA ligands, including two stereoisomers of a phosphorothioate linkage. The selectivity for singly substituted poly(A) sequences suggests LARP1 may play a role in the stabilizing effect of poly(A) tail guanylation. [Figure: see text].
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Affiliation(s)
- Guennadi Kozlov
- Department of Biochemistry, McGill University, Montréal, Quebec, Canada
- Centre de recherche en biologie structurale, McGill University, Montréal, Quebec, Canada
| | - Jianning Jiang
- Department of Biochemistry, McGill University, Montréal, Quebec, Canada
- Centre de recherche en biologie structurale, McGill University, Montréal, Quebec, Canada
| | - Tyler Rutherford
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Quebec, Canada
| | - Anne M. Noronha
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Quebec, Canada
| | - Christopher J. Wilds
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Quebec, Canada
| | - Kalle Gehring
- Department of Biochemistry, McGill University, Montréal, Quebec, Canada
- Centre de recherche en biologie structurale, McGill University, Montréal, Quebec, Canada
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13
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Arrivé M, Bruggeman M, Skaltsogiannis V, Coudray L, Quan YF, Schelcher C, Cognat V, Hammann P, Chicher J, Wolff P, Gobert A, Giegé P. A tRNA-modifying enzyme facilitates RNase P activity in Arabidopsis nuclei. NATURE PLANTS 2023; 9:2031-2041. [PMID: 37945696 DOI: 10.1038/s41477-023-01564-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 10/09/2023] [Indexed: 11/12/2023]
Abstract
RNase P is the essential activity that performs the 5' maturation of transfer RNA (tRNA) precursors. Beyond the ancestral form of RNase P containing a ribozyme, protein-only RNase P enzymes termed PRORP were identified in eukaryotes. In human mitochondria, PRORP forms a complex with two protein partners to become functional. In plants, although PRORP enzymes are active alone, we investigate their interaction network to identify potential tRNA maturation complexes. Here we investigate functional interactions involving the Arabidopsis nuclear RNase P PRORP2. We show, using an immuno-affinity strategy, that PRORP2 occurs in a complex with the tRNA methyl transferases TRM1A and TRM1B in vivo. Beyond RNase P, these enzymes can also interact with RNase Z. We show that TRM1A/TRM1B localize in the nucleus and find that their double knockout mutation results in a severe macroscopic phenotype. Using a combination of immuno-detections, mass spectrometry and a transcriptome-wide tRNA sequencing approach, we observe that TRM1A/TRM1B are responsible for the m22G26 modification of 70% of cytosolic tRNAs in vivo. We use the transcriptome wide tRNAseq approach as well as RNA blot hybridizations to show that RNase P activity is impaired in TRM1A/TRM1B mutants for specific tRNAs, in particular, tRNAs containing a m22G modification at position 26 that are strongly downregulated in TRM1A/TRM1B mutants. Altogether, results indicate that the m22G-adding enzymes TRM1A/TRM1B functionally cooperate with nuclear RNase P in vivo for the early steps of cytosolic tRNA biogenesis.
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Affiliation(s)
- Mathilde Arrivé
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Mathieu Bruggeman
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Vasileios Skaltsogiannis
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Léna Coudray
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Yi-Fat Quan
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
- Department of Plant Molecular Biology, University of Lausanne, Lausanne, Switzerland
| | - Cédric Schelcher
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Valérie Cognat
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Philippe Hammann
- Plateforme protéomique Strasbourg Esplanade, FR1589 du CNRS, Strasbourg, France
| | - Johana Chicher
- Plateforme protéomique Strasbourg Esplanade, FR1589 du CNRS, Strasbourg, France
| | - Philippe Wolff
- Plateforme protéomique Strasbourg Esplanade, FR1589 du CNRS, Strasbourg, France
- Architecture et Réactivité de l'ARN, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, Strasbourg, France
| | - Anthony Gobert
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Philippe Giegé
- Institut de biologie moléculaire des plantes, UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
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14
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Goswami B, Nag S, Ray PS. Fates and functions of RNA-binding proteins under stress. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023:e1825. [PMID: 38014833 DOI: 10.1002/wrna.1825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 10/03/2023] [Accepted: 10/30/2023] [Indexed: 11/29/2023]
Abstract
Exposure to stress activates a well-orchestrated set of changes in gene expression programs that allow the cell to cope with and adapt to the stress, or undergo programmed cell death. RNA-protein interactions, mediating all aspects of post-transcriptional regulation of gene expression, play crucial roles in cellular stress responses. RNA-binding proteins (RBPs), which interact with sequence/structural elements in RNAs to control the steps of RNA metabolism, have therefore emerged as central regulators of post-transcriptional responses to stress. Following exposure to a variety of stresses, the dynamic alterations in the RNA-protein interactome enable cells to respond to intracellular or extracellular perturbations by causing changes in mRNA splicing, polyadenylation, stability, translation, and localization. As RBPs play a central role in determining the cellular proteome both qualitatively and quantitatively, it has become increasingly evident that their abundance, availability, and functions are also highly regulated in response to stress. Exposure to stress initiates a series of signaling cascades that converge on post-translational modifications (PTMs) of RBPs, resulting in changes in their subcellular localization, association with stress granules, extracellular export, proteasomal degradation, and RNA-binding activities. These alterations in the fate and function of RBPs directly impact their post-transcriptional regulatory roles in cells under stress. Adopting the ubiquitous RBP HuR as a prototype, three scenarios illustrating the changes in nuclear-cytoplasmic localization, RNA-binding activity, export and degradation of HuR in response to inflammation, genotoxic stress, and heat shock depict the complex and interlinked regulatory mechanisms that control the fate and functions of RBPs under stress. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Binita Goswami
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohanpur, West Bengal, India
| | - Sharanya Nag
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohanpur, West Bengal, India
| | - Partho Sarothi Ray
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohanpur, West Bengal, India
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15
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Mansouri-Noori F, Pircher A, Bilodeau D, Siniavskaia L, Grigull J, Rissland OS, Bayfield MA. The LARP1 homolog Slr1p controls the stability and expression of proto-5'TOP mRNAs in fission yeast. Cell Rep 2023; 42:113226. [PMID: 37851576 DOI: 10.1016/j.celrep.2023.113226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/09/2023] [Accepted: 09/22/2023] [Indexed: 10/20/2023] Open
Abstract
Messenger RNAs (mRNAs) in higher eukaryotes that encode proteins important for the assembly of the translational apparatus (e.g., ribosomal proteins) often harbor a pyrimidine-rich motif at the extreme 5' end known as a 5' terminal oligopyrimidine (5'TOP) sequence. Members of the La-related protein 1 (LARP1) family control 5'TOP expression through a conserved DM15 motif, but the mechanism is not well understood. 5'TOP motifs have not been described in many lower organisms, and fission yeast harbors a LARP1 homolog that also lacks a DM15 motif. In this work, we show that the fission yeast LARP1 homolog, Slr1p, controls the translation and stability of mRNAs encoding proteins analogous to 5'TOP mRNAs in higher eukaryotes, which we thus refer to as proto-5'TOPs. Our data suggest that the LARP1 DM15 motif and the mRNA 5'TOP motif may be features that were scaffolded over a more fundamental mechanism of LARP1-associated control of gene expression.
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Affiliation(s)
| | | | - Danielle Bilodeau
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
| | | | - Jörg Grigull
- Department of Mathematics and Statistics, York University, Toronto, Canada
| | - Olivia S Rissland
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
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16
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Weigert N, Schweiger AL, Gross J, Matthes M, Corbacioglu S, Sommer G, Heise T. Detection of a 7SL RNA-derived small non-coding RNA using Molecular Beacons in vitro and in cells. Biol Chem 2023; 404:1123-1136. [PMID: 37632732 DOI: 10.1515/hsz-2023-0185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 08/11/2023] [Indexed: 08/28/2023]
Abstract
Small non-coding RNAs (sncRNA) are involved in many steps of the gene expression cascade and regulate processing and expression of mRNAs by the formation of ribonucleoprotein complexes (RNP) such as the RNA-induced silencing complex (RISC). By analyzing small RNA Seq data sets, we identified a sncRNA annotated as piR-hsa-1254, which is likely derived from the 3'-end of 7SL RNA2 (RN7SL2), herein referred to as snc7SL RNA. The 7SL RNA is an abundant long non-coding RNA polymerase III transcript and serves as structural component of the cytoplasmic signal recognition particle (SRP). To evaluate a potential functional role of snc7SL RNA, we aimed to define its cellular localization by live cell imaging. Therefore, a Molecular Beacon (MB)-based method was established to compare the subcellular localization of snc7SL RNA with its precursor 7SL RNA. We designed and characterized several MBs in vitro and tested those by live cell fluorescence microscopy. Using a multiplex approach, we show that 7SL RNA localizes mainly to the endoplasmic reticulum (ER), as expected for the SRP, whereas snc7SL RNA predominately localizes to the nucleus. This finding suggests a fundamentally different function of 7SL RNA and its derivate snc7SL RNA.
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Affiliation(s)
- Nina Weigert
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Anna-Lena Schweiger
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Jonas Gross
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Marie Matthes
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Selim Corbacioglu
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Gunhild Sommer
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
| | - Tilman Heise
- Department for Pediatric Hematology, Oncology and Stem Cell Transplantation, University Hospital Regensburg, Franz-Josef-Strauß Allee 11, D-93053 Regensburg, Germany
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17
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Zhou S, Van Bortle K. The Pol III transcriptome: Basic features, recurrent patterns, and emerging roles in cancer. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1782. [PMID: 36754845 PMCID: PMC10498592 DOI: 10.1002/wrna.1782] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 02/10/2023]
Abstract
The RNA polymerase III (Pol III) transcriptome is universally comprised of short, highly structured noncoding RNA (ncRNA). Through RNA-protein interactions, the Pol III transcriptome actuates functional activities ranging from nuclear gene regulation (7SK), splicing (U6, U6atac), and RNA maturation and stability (RMRP, RPPH1, Y RNA), to cytoplasmic protein targeting (7SL) and translation (tRNA, 5S rRNA). In higher eukaryotes, the Pol III transcriptome has expanded to include additional, recently evolved ncRNA species that effectively broaden the footprint of Pol III transcription to additional cellular activities. Newly evolved ncRNAs function as riboregulators of autophagy (vault), immune signaling cascades (nc886), and translation (Alu, BC200, snaR). Notably, upregulation of Pol III transcription is frequently observed in cancer, and multiple ncRNA species are linked to both cancer progression and poor survival outcomes among cancer patients. In this review, we outline the basic features and functions of the Pol III transcriptome, and the evidence for dysregulation and dysfunction for each ncRNA in cancer. When taken together, recurrent patterns emerge, ranging from shared functional motifs that include molecular scaffolding and protein sequestration, overlapping protein interactions, and immunostimulatory activities, to the biogenesis of analogous small RNA fragments and noncanonical miRNAs, augmenting the function of the Pol III transcriptome and further broadening its role in cancer. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > Processing of Small RNAs RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Sihang Zhou
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Kevin Van Bortle
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Cancer Center at Illinois, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
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18
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Dhungel P, Brahim Belhaouari D, Yang Z. La-related protein 4 is enriched in vaccinia virus factories and is required for efficient viral replication in primary human fibroblasts. Microbiol Spectr 2023; 11:e0139023. [PMID: 37594266 PMCID: PMC10581054 DOI: 10.1128/spectrum.01390-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 07/06/2023] [Indexed: 08/19/2023] Open
Abstract
In addition to the 3'-poly(A) tail, vaccinia virus mRNAs synthesized after viral DNA replication (post-replicative mRNAs) possess a 5'-poly(A) leader that confers a translational advantage in virally infected cells. These mRNAs are synthesized in viral factories, the cytoplasmic compartment where vaccinia virus DNA replication, mRNA synthesis, and translation occur. However, a previous study indicates that the poly(A)-binding protein (PABPC1)-which has a well-established role in RNA stability and translation-is absent in the viral factories. This prompts the question of whether other poly(A)-binding proteins engage vaccinia virus post-replicative mRNA in viral factories. Here, in this study, we found that La-related protein 4 (LARP4), a poly(A) binding protein, was enriched in viral factories in multiple types of cells during vaccinia virus infection. Further studies showed that LARP4 enrichment in the viral factories required viral post-replicative gene expression and functional decapping enzymes encoded by vaccinia virus. We further showed that knockdown of LARP4 expression in human foreskin fibroblasts (HFFs) reduced vaccinia virus DNA replication, post-replicative protein levels, and viral production. Interestingly, the knockdown of LARP4 expression also reduced protein levels from transfected mRNA containing a 5'-poly(A) leader in vaccinia virus-infected and uninfected HFFs. Taken together, our results identified a poly(A)-binding protein, LARP4, being enriched in the vaccinia virus viral factories and facilitating viral replication in HFFs. IMPORTANCE Vaccinia virus, the prototype poxvirus, encodes over 200 open reading frames (ORFs). Over 90 of vaccinia virus ORFs are transcribed post-viral DNA replication. All these mRNAs contain a 5'-poly(A) leader, as well as a 3'-poly(A) tail. They are synthesized in viral factories, where vaccinia virus DNA replication, mRNA synthesis, and translation occur. However, surprisingly, the poly(A) binding protein, PABPC1, that is important for mRNA metabolism and translation is not present in the viral factories, suggesting other poly(A) binding protein(s) may be present in viral factories. Here, we found another poly(A)-binding protein, La-related protein 4 (LARP4), enriched in viral factories during vaccinia virus infection. We also showed that LARP4 enrichment in the viral factories depends on viral post-replicative gene expression and functional viral decapping enzymes. The knockdown of LARP4 expression in human foreskin fibroblasts reduced vaccinia virus DNA replication, post-replicative gene expression, and viral production.
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Affiliation(s)
- Pragyesh Dhungel
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Djamal Brahim Belhaouari
- Department of Veterinary Pathobiology, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Zhilong Yang
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
- Department of Veterinary Pathobiology, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas, USA
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19
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Wang Y, He Y, Wang Y, Yang Y, Singh M, Eichhorn CD, Cheng X, Jiang YX, Zhou ZH, Feigon J. Structure of LARP7 Protein p65-telomerase RNA Complex in Telomerase Revealed by Cryo-EM and NMR. J Mol Biol 2023; 435:168044. [PMID: 37330293 PMCID: PMC10988774 DOI: 10.1016/j.jmb.2023.168044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 06/19/2023]
Abstract
La-related protein 7 (LARP7) are a family of RNA chaperones that protect the 3'-end of RNA and are components of specific ribonucleoprotein complexes (RNP). In Tetrahymena thermophila telomerase, LARP7 protein p65 together with telomerase reverse transcriptase (TERT) and telomerase RNA (TER) form the core RNP. p65 has four known domains-N-terminal domain (NTD), La motif (LaM), RNA recognition motif 1 (RRM1), and C-terminal xRRM2. To date, only the xRRM2 and LaM and their interactions with TER have been structurally characterized. Conformational dynamics leading to low resolution in cryo-EM density maps have limited our understanding of how full-length p65 specifically recognizes and remodels TER for telomerase assembly. Here, we combined focused classification of Tetrahymena telomerase cryo-EM maps with NMR spectroscopy to determine the structure of p65-TER. Three previously unknown helices are identified, one in the otherwise intrinsically disordered NTD that binds the La module, one that extends RRM1, and another preceding xRRM2, that stabilize p65-TER interactions. The extended La module (αN, LaM and RRM1) interacts with the four 3' terminal U nucleotides, while LaM and αN additionally interact with TER pseudoknot, and LaM with stem 1 and 5' end. Our results reveal the extensive p65-TER interactions that promote TER 3'-end protection, TER folding, and core RNP assembly and stabilization. The structure of full-length p65 with TER also sheds light on the biological roles of genuine La and LARP7 proteins as RNA chaperones and core RNP components.
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Affiliation(s)
- Yaqiang Wang
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Yao He
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA; Department of Microbiology, Immunology, and Molecular Genetics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Yanjiao Wang
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Yuan Yang
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Mahavir Singh
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Catherine D Eichhorn
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Xinyi Cheng
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Yi Xiao Jiang
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA
| | - Z Hong Zhou
- Department of Microbiology, Immunology, and Molecular Genetics, University of California Los Angeles, Los Angeles, CA 90095, USA; California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095-1569, USA.
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20
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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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21
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Camara MB, Sobeh AM, Eichhorn CD. Progress in 7SK ribonucleoprotein structural biology. Front Mol Biosci 2023; 10:1154622. [PMID: 37051324 PMCID: PMC10083321 DOI: 10.3389/fmolb.2023.1154622] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 03/16/2023] [Indexed: 03/29/2023] Open
Abstract
The 7SK ribonucleoprotein (RNP) is a dynamic and multifunctional regulator of RNA Polymerase II (RNAPII) transcription in metazoa. Comprised of the non-coding 7SK RNA, core proteins, and numerous accessory proteins, the most well-known 7SK RNP function is the sequestration and inactivation of the positive transcription elongation factor b (P-TEFb). More recently, 7SK RNP has been shown to regulate RNAPII transcription through P-TEFb-independent pathways. Due to its fundamental role in cellular function, dysregulation has been linked with human diseases including cancers, heart disease, developmental disorders, and viral infection. Significant advances in 7SK RNP structural biology have improved our understanding of 7SK RNP assembly and function. Here, we review progress in understanding the structural basis of 7SK RNA folding, biogenesis, and RNP assembly.
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Affiliation(s)
- Momodou B. Camara
- Department of Chemistry, University of Nebraska, Lincoln, NE, United States
| | - Amr M. Sobeh
- Department of Chemistry, University of Nebraska, Lincoln, NE, United States
| | - Catherine D. Eichhorn
- Department of Chemistry, University of Nebraska, Lincoln, NE, United States
- Nebraska Center for Integrated Biomolecular Communication, Lincoln, NE, United States
- *Correspondence: Catherine D. Eichhorn,
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22
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Dhungel P, Brahim Belhaouari D, Yang Z. La-related protein 4 is enriched in vaccinia virus factories and is required for efficient viral replication in primary human fibroblasts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.10.532125. [PMID: 36945573 PMCID: PMC10029068 DOI: 10.1101/2023.03.10.532125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2023]
Abstract
In addition to the 3'-poly(A) tail, vaccinia virus mRNAs synthesized after viral DNA replication (post-replicative mRNAs) possess a 5'-poly(A) leader that confers a translational advantage in virally infected cells. These mRNAs are synthesized in viral factories, the cytoplasmic compartment where vaccinia virus DNA replication, mRNA synthesis, and translation occur. However, a previous study indicates that the poly(A)-binding protein (PABPC1)-which has a well-established role in RNA stability and translation-is not present in the viral factories. This prompts the question of whether another poly(A)-binding protein engages vaccinia virus post-replicative mRNA in viral factories. In this study, we found that La-related protein 4 (LARP4), a poly(A) binding protein, was enriched in viral factories in multiple types of cells during vaccinia virus infection. Further studies showed that LARP4 enrichment in the viral factories required viral post-replicative gene expression and functional decapping enzymes encoded by vaccinia virus. We further showed that knockdown of LARP4 expression in human foreskin fibroblasts (HFFs) significantly reduced vaccinia virus post-replicative gene expression and viral replication. Interestingly, the knockdown of LARP4 expression also reduced 5'-poly(A) leader-mediated mRNA translation in vaccinia virus-infected and uninfected HFFs. Together, our results identified a poly(A)-binding protein, LARP4, enriched in the vaccinia virus viral factories and facilitates viral replication and mRNA translation. Importance Poxviruses are a family of large DNA viruses comprising members infecting a broad range of hosts, including many animals and humans. Poxvirus infections can cause deadly diseases in humans and animals. Vaccinia virus, the prototype poxvirus, encodes over 200 open reading frames (ORFs). Over 90 of vaccinia virus ORFs are transcribed post-viral DNA replication. All these mRNAs contain a 5'-poly(A) leader, as well as a 3'-poly(A) tail. They are synthesized in viral factories, where vaccinia virus DNA replication, mRNA synthesis and translation occur. However, surprisingly, the poly(A) binding protein (PABPC1) that is important for mRNA metabolism and translation is not present in the viral factories, suggesting other poly(A) binding protein(s) may be present in viral factories. Here we found another poly(A)-binding protein, La-related protein 4 (LARP4), is enriched in viral factories during vaccinia virus infection. We also showed that LARP4 enrichment in the viral factories depends on viral post-replicative gene expression and functional viral decapping enzymes. The knockdown of LARP4 expression in human foreskin fibroblasts (HFFs) significantly reduced vaccinia virus post-replicative gene expression and viral replication. Overall, this study identified a poly(A)-binding protein that plays an important role in vaccinia virus replication.
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Affiliation(s)
- Pragyesh Dhungel
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Djamal Brahim Belhaouari
- Department of Veterinary Pathobiology, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Zhilong Yang
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
- Department of Veterinary Pathobiology, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
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23
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Goering R, Arora A, Pockalny MC, Taliaferro JM. RNA localization mechanisms transcend cell morphology. eLife 2023; 12:e80040. [PMID: 36867563 PMCID: PMC9984196 DOI: 10.7554/elife.80040] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 01/24/2023] [Indexed: 03/04/2023] Open
Abstract
RNA molecules are localized to specific subcellular regions through interactions between RNA regulatory elements and RNA binding proteins (RBPs). Generally, our knowledge of the mechanistic details behind the localization of a given RNA is restricted to a particular cell type. Here, we show that RNA/RBP interactions that regulate RNA localization in one cell type predictably regulate localization in other cell types with vastly different morphologies. To determine transcriptome-wide RNA spatial distributions across the apicobasal axis of human intestinal epithelial cells, we used our recently developed RNA proximity labeling technique, Halo-seq. We found that mRNAs encoding ribosomal proteins (RP mRNAs) were strongly localized to the basal pole of these cells. Using reporter transcripts and single-molecule RNA FISH, we found that pyrimidine-rich motifs in the 5' UTRs of RP mRNAs were sufficient to drive basal RNA localization. Interestingly, the same motifs were also sufficient to drive RNA localization to the neurites of mouse neuronal cells. In both cell types, the regulatory activity of this motif was dependent on it being in the 5' UTR of the transcript, was abolished upon perturbation of the RNA-binding protein LARP1, and was reduced upon inhibition of kinesin-1. To extend these findings, we compared subcellular RNAseq data from neuronal and epithelial cells. We found that the basal compartment of epithelial cells and the projections of neuronal cells were enriched for highly similar sets of RNAs, indicating that broadly similar mechanisms may be transporting RNAs to these morphologically distinct locations. These findings identify the first RNA element known to regulate RNA localization across the apicobasal axis of epithelial cells, establish LARP1 as an RNA localization regulator, and demonstrate that RNA localization mechanisms cut across cell morphologies.
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Affiliation(s)
- Raeann Goering
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical CampusAuroraUnited States
- RNA Bioscience Initiative, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Ankita Arora
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Megan C Pockalny
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - J Matthew Taliaferro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical CampusAuroraUnited States
- RNA Bioscience Initiative, University of Colorado Anschutz Medical CampusAuroraUnited States
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24
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Park J, Kim M, Yi H, Baeg K, Choi Y, Lee YS, Lim J, Kim VN. Short poly(A) tails are protected from deadenylation by the LARP1-PABP complex. Nat Struct Mol Biol 2023; 30:330-338. [PMID: 36849640 DOI: 10.1038/s41594-023-00930-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/10/2023] [Indexed: 03/01/2023]
Abstract
Deadenylation generally constitutes the first and pivotal step in eukaryotic messenger RNA decay. Despite its importance in posttranscriptional regulations, the kinetics of deadenylation and its regulation remain largely unexplored. Here we identify La ribonucleoprotein 1, translational regulator (LARP1) as a general decelerator of deadenylation, which acts mainly in the 30-60-nucleotide (nt) poly(A) length window. We measured the steady-state and pulse-chased distribution of poly(A)-tail length, and found that deadenylation slows down in the 30-60-nt range. LARP1 associates preferentially with short tails and its depletion results in accelerated deadenylation specifically in the 30-60-nt range. Consistently, LARP1 knockdown leads to a global reduction of messenger RNA abundance. LARP1 interferes with the CCR4-NOT-mediated deadenylation in vitro by forming a ternary complex with poly(A)-binding protein (PABP) and poly(A). Together, our work reveals a dynamic nature of deadenylation kinetics and a role of LARP1 as a poly(A) length-specific barricade that creates a threshold for deadenylation.
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Affiliation(s)
- Joha Park
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- School of Biological Sciences, Seoul National University, Seoul, Korea
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Myeonghwan Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Hyerim Yi
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- School of Biological Sciences, Seoul National University, Seoul, Korea
- Stanford University School of Medicine, Stanford, CA, USA
| | - Kyungmin Baeg
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
| | - Yongkuk Choi
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Young-Suk Lee
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Jaechul Lim
- Center for RNA Research, Institute for Basic Science, Seoul, Korea
- School of Biological Sciences, Seoul National University, Seoul, Korea
- Yale School of Medicine, New Haven, CT, USA
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Korea.
- School of Biological Sciences, Seoul National University, Seoul, Korea.
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25
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Cell surface-bound La protein regulates the cell fusion stage of osteoclastogenesis. Nat Commun 2023; 14:616. [PMID: 36739273 PMCID: PMC9899215 DOI: 10.1038/s41467-023-36168-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/16/2023] [Indexed: 02/06/2023] Open
Abstract
Multinucleated osteoclasts, essential for skeletal remodeling in health and disease, are formed by the fusion of osteoclast precursors, where each fusion event raises their bone-resorbing activity. Here we show that the nuclear RNA chaperone, La protein has an additional function as an osteoclast fusion regulator. Monocyte-to-osteoclast differentiation starts with a drastic decrease in La levels. As fusion begins, La reappears as a low molecular weight species at the osteoclast surface, where it promotes fusion. La's role in promoting osteoclast fusion is independent of canonical La-RNA interactions and involves direct interactions between La and Annexin A5, which anchors La to transiently exposed phosphatidylserine at the surface of fusing osteoclasts. Disappearance of cell-surface La, and the return of full length La to the nuclei of mature, multinucleated osteoclasts, acts as an off switch of their fusion activity. Targeting surface La in a novel explant model of fibrous dysplasia inhibits excessive osteoclast formation characteristic of this disease, highlighting La's potential as a therapeutic target.
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26
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Mao Z, Nakamura F. Interaction of LARP4 to filamin A mechanosensing domain regulates cell migrations. Front Cell Dev Biol 2023; 11:1152109. [PMID: 37169020 PMCID: PMC10164935 DOI: 10.3389/fcell.2023.1152109] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 04/14/2023] [Indexed: 05/13/2023] Open
Abstract
Filamin A (FLNA) is an actin cross-linking protein that mediates mechanotransduction. Force-dependent conformational changes of FLNA molecule expose cryptic binding site of FLNA, allowing interaction with partners such as integrin, smoothelin, and fimbacin. Here, we identified La-related protein 4 (LARP4) as a new FLNA mechanobinding partner. LARP4 specifically interacts with the cleft formed by C and D strands of immunoglobulin-like repeat 21 (R21) which is blocked by A strand of R20 without force. We validated the interaction between LARP4 and FLNA R21 both in vivo and in vitro. We also determined the critical amino acid that is responsible for the interaction and generated the non-FLNA-binding mutant LARP4 (F277A in human: F273A in mouse Larp4) that disrupts the interaction. Fluorescence recovery after photobleaching (FRAP) of GFP-labeled LARP4 in living cells demonstrated that mutant LARP4 diffuses faster than WT LARP4. Proximity ligation assay (PLA) also confirmed their interaction and disruption of actin polymerization diminishes the interaction. Data mining of RNAseq analysis of LARP4 knockdown (KD) HEK293T cells suggested that LARP4 is involved in morphogenesis and cell motility. Consistent with this prediction, we found that KD of LARP4 increases cell migration speed and expression of the F277A mutant LARP4 in LARP4-KD cells also leads to a higher cell migration speed compared to WT LARP4. These results demonstrated that the LARP4 interaction with FLNA regulates cell migration.
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27
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Mehta M, Raguraman R, Ramesh R, Munshi A. RNA binding proteins (RBPs) and their role in DNA damage and radiation response in cancer. Adv Drug Deliv Rev 2022; 191:114569. [PMID: 36252617 PMCID: PMC10411638 DOI: 10.1016/j.addr.2022.114569] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 01/24/2023]
Abstract
Traditionally majority of eukaryotic gene expression is influenced by transcriptional and post-transcriptional events. Alterations in the expression of proteins that act post-transcriptionally can affect cellular signaling and homeostasis. RNA binding proteins (RBPs) are a family of proteins that specifically bind to RNAs and are involved in post-transcriptional regulation of gene expression and important cellular processes such as cell differentiation and metabolism. Deregulation of RNA-RBP interactions and any changes in RBP expression or function can lead to various diseases including cancer. In cancer cells, RBPs play an important role in regulating the expression of tumor suppressors and oncoproteins involved in various cell-signaling pathways. Several RBPs such as HuR, AUF1, RBM38, LIN28, RBM24, tristetrapolin family and Musashi play critical roles in various types of cancers and their aberrant expression in cancer cells makes them an attractive therapeutic target for cancer treatment. In this review we provide an overview of i). RBPs involved in cancer progression and their mechanism of action ii). the role of RBPs, including HuR, in breast cancer progression and DNA damage response and iii). explore RBPs with emphasis on HuR as therapeutic target for breast cancer therapy.
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Affiliation(s)
- Meghna Mehta
- Department of Radiation Oncology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Rajeswari Raguraman
- Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Rajagopal Ramesh
- Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Anupama Munshi
- Department of Radiation Oncology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA.
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28
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Guo J, Xue H, Zhong H, Sun W, Zhao S, Meng J, Jiang P. Involvement of LARP7 in Activation of SIRT1 to Inhibit NF-κB Signaling Protects Microglia from Acrylamide-Induced Neuroinflammation. Neurotox Res 2022; 40:2016-2026. [PMID: 36550222 DOI: 10.1007/s12640-022-00624-1] [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: 05/23/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022]
Abstract
Acrylamide (AM) is a potent neurotoxin and carcinogen that is mainly formed by the Maillard reaction of asparagine with starch at high temperatures. However, the toxicity mechanism underlying AM has not been investigated from a proteomic perspective, and the regulation of protein expression by AM remains poorly understood. This research was the first to utilize proteomics to explore the mechanism of AM exposure-induced neuroinflammation. Target proteins were obtained by differential protein analysis, functional annotation, and enrichment analysis of proteomics. Then, molecular biology methods, including Western blot, qPCR, and immunofluorescence, were used to verify the results and explore possible mechanisms. We identified 100 key differential metabolites by proteomic analysis, which was involved in the occurrence of various biological functions. Among them, the KEGG pathway enrichment analysis showed that the differential proteins were enriched in the P53 pathway, sulfur metabolism pathway, and ferroptosis. Finally, the differential target protein we locked was LARP7. Molecular biological verification found that AM exposure inhibited the expression of LARP7 and induced the burst of inflammation, while SRT1720 agonist treatment showed no effect on LARP7, but significant changes in inflammatory factors and NF-κB. Taken together, these findings suggested that AM may activate NF-κB to induce neuroinflammation by inhibiting the LARP7-SIRT1 pathway. And our study provided a direction for AM-induced neurotoxicity through proteomics and multiple biological analysis methods.
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Affiliation(s)
- Jinxiu Guo
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China.,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China
| | - Hongjia Xue
- Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo, 315100, China
| | - Haitao Zhong
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China. .,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China.
| | - Wenxue Sun
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China.,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China.,Shandong University of Traditional Chinese Medicine, Jinan, Shandong, 250355, China
| | - Shiyuan Zhao
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China.,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China
| | - Junjun Meng
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China.,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China
| | - Pei Jiang
- Translational Pharmaceutical Laboratory, Jining First People's Hospital, Shandong First Medical University, Jining, 272000, China. .,Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, 272000, China.
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29
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mTOR- and LARP1-dependent regulation of TOP mRNA poly(A) tail and ribosome loading. Cell Rep 2022; 41:111548. [DOI: 10.1016/j.celrep.2022.111548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 08/30/2022] [Accepted: 09/30/2022] [Indexed: 11/20/2022] Open
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30
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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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31
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Kozlov G, Mattijssen S, Jiang J, Nyandwi S, Sprules T, Iben J, Coon S, Gaidamakov S, Noronha AM, Wilds C, Maraia R, Gehring K. Structural basis of 3'-end poly(A) RNA recognition by LARP1. Nucleic Acids Res 2022; 50:9534-9547. [PMID: 35979957 PMCID: PMC9458460 DOI: 10.1093/nar/gkac696] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/21/2022] [Accepted: 08/02/2022] [Indexed: 12/24/2022] Open
Abstract
La-related proteins (LARPs) comprise a family of RNA-binding proteins involved in a wide range of posttranscriptional regulatory activities. LARPs share a unique tandem of two RNA-binding domains, La motif (LaM) and RNA recognition motif (RRM), together referred to as a La-module, but vary in member-specific regions. Prior structural studies of La-modules reveal they are pliable platforms for RNA recognition in diverse contexts. Here, we characterize the La-module of LARP1, which plays an important role in regulating synthesis of ribosomal proteins in response to mTOR signaling and mRNA stabilization. LARP1 has been well characterized functionally but no structural information exists for its La-module. We show that unlike other LARPs, the La-module in LARP1 does not contain an RRM domain. The LaM alone is sufficient for binding poly(A) RNA with submicromolar affinity and specificity. Multiple high-resolution crystal structures of the LARP1 LaM domain in complex with poly(A) show that it is highly specific for the RNA 3'-end, and identify LaM residues Q333, Y336 and F348 as the most critical for binding. Use of a quantitative mRNA stabilization assay and poly(A) tail-sequencing demonstrate functional relevance of LARP1 RNA binding in cells and provide novel insight into its poly(A) 3' protection activity.
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Affiliation(s)
- Guennadi Kozlov
- Department of Biochemistry, McGill University, Montréal, Canada,Centre de recherche en biologie structurale, McGill University, Montréal, Canada
| | - Sandy Mattijssen
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Jianning Jiang
- Department of Biochemistry, McGill University, Montréal, Canada,Centre de recherche en biologie structurale, McGill University, Montréal, Canada
| | - Samuel Nyandwi
- Department of Biochemistry, McGill University, Montréal, Canada,Centre de recherche en biologie structurale, McGill University, Montréal, Canada
| | - Tara Sprules
- Centre de recherche en biologie structurale, McGill University, Montréal, Canada,Quebec/Eastern Canada NMR Centre, McGill University, Montréal, Canada
| | - James R Iben
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Steven L Coon
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Sergei Gaidamakov
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Anne M Noronha
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Canada
| | - Christopher J Wilds
- Department of Chemistry and Biochemistry, Concordia University, Montréal, 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
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32
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Yang Y, Liu S, Egloff S, Eichhorn CD, Hadjian T, Zhen J, Kiss T, Zhou ZH, Feigon J. Structural basis of RNA conformational switching in the transcriptional regulator 7SK RNP. Mol Cell 2022; 82:1724-1736.e7. [PMID: 35320752 PMCID: PMC9081187 DOI: 10.1016/j.molcel.2022.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 12/27/2021] [Accepted: 02/28/2022] [Indexed: 01/05/2023]
Abstract
7SK non-coding RNA (7SK) negatively regulates RNA polymerase II (RNA Pol II) elongation by inhibiting positive transcription elongation factor b (P-TEFb), and its ribonucleoprotein complex (RNP) is hijacked by HIV-1 for viral transcription and replication. Methylphosphate capping enzyme (MePCE) and La-related protein 7 (Larp7) constitutively associate with 7SK to form a core RNP, while P-TEFb and other proteins dynamically assemble to form different complexes. Here, we present the cryo-EM structures of 7SK core RNP formed with two 7SK conformations, circular and linear, and uncover a common RNA-dependent MePCE-Larp7 complex. Together with NMR, biochemical, and cellular data, these structures reveal the mechanism of MePCE catalytic inactivation in the core RNP, unexpected interactions between Larp7 and RNA that facilitate a role as an RNP chaperone, and that MePCE-7SK-Larp7 core RNP serves as a scaffold for switching between different 7SK conformations essential for RNP assembly and regulation of P-TEFb sequestration and release.
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Affiliation(s)
- Yuan Yang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Shiheng Liu
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sylvain Egloff
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Catherine D Eichhorn
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tanya Hadjian
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - James Zhen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA; California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tamás Kiss
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France; Biological Research Centre, Szeged, Temesvári krt. 62, 6726, Hungary
| | - Z Hong Zhou
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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33
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Structural insights into nuclear transcription by eukaryotic DNA-dependent RNA polymerases. Nat Rev Mol Cell Biol 2022; 23:603-622. [PMID: 35505252 DOI: 10.1038/s41580-022-00476-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2022] [Indexed: 02/07/2023]
Abstract
The eukaryotic transcription apparatus synthesizes a staggering diversity of RNA molecules. The labour of nuclear gene transcription is, therefore, divided among multiple DNA-dependent RNA polymerases. RNA polymerase I (Pol I) transcribes ribosomal RNA, Pol II synthesizes messenger RNAs and various non-coding RNAs (including long non-coding RNAs, microRNAs and small nuclear RNAs) and Pol III produces transfer RNAs and other short RNA molecules. Pol I, Pol II and Pol III are large, multisubunit protein complexes that associate with a multitude of additional factors to synthesize transcripts that largely differ in size, structure and abundance. The three transcription machineries share common characteristics, but differ widely in various aspects, such as numbers of RNA polymerase subunits, regulatory elements and accessory factors, which allows them to specialize in transcribing their specific RNAs. Common to the three RNA polymerases is that the transcription process consists of three major steps: transcription initiation, transcript elongation and transcription termination. In this Review, we outline the common principles and differences between the Pol I, Pol II and Pol III transcription machineries and discuss key structural and functional insights obtained into the three stages of their transcription processes.
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34
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Páez-Moscoso DJ, Ho DV, Pan L, Hildebrand K, Jensen KL, Levy MJ, Florens L, Baumann P. A putative cap binding protein and the methyl phosphate capping enzyme Bin3/MePCE function in telomerase biogenesis. Nat Commun 2022; 13:1067. [PMID: 35217638 PMCID: PMC8881624 DOI: 10.1038/s41467-022-28545-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 01/13/2022] [Indexed: 01/29/2023] Open
Abstract
Telomerase reverse transcriptase (TERT) and the noncoding telomerase RNA (TR) subunit constitute the core of telomerase. Additional subunits are required for ribonucleoprotein complex assembly and in some cases remain stably associated with the active holoenzyme. Pof8, a member of the LARP7 protein family is such a constitutive component of telomerase in fission yeast. Using affinity purification of Pof8, we have identified two previously uncharacterized proteins that form a complex with Pof8 and participate in telomerase biogenesis. Both proteins participate in ribonucleoprotein complex assembly and are required for wildtype telomerase activity and telomere length maintenance. One factor we named Thc1 (Telomerase Holoenzyme Component 1) shares structural similarity with the nuclear cap binding complex and the poly-adenosine ribonuclease (PARN), the other is the ortholog of the methyl phosphate capping enzyme (Bin3/MePCE) in metazoans and was named Bmc1 (Bin3/MePCE 1) to reflect its evolutionary roots. Thc1 and Bmc1 function together with Pof8 in recognizing correctly folded telomerase RNA and promoting the recruitment of the Lsm2-8 complex and the catalytic subunit to assemble functional telomerase.
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Affiliation(s)
- Diego J Páez-Moscoso
- Faculty of Biology, Johannes Gutenberg University, 55099, Mainz, Germany
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- Institute of Molecular Biology, Ackermannweg, 4 55128, Mainz, Germany
| | - David V Ho
- Faculty of Biology, Johannes Gutenberg University, 55099, Mainz, Germany
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Lili Pan
- Faculty of Biology, Johannes Gutenberg University, 55099, Mainz, Germany
| | - Katie Hildebrand
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- Transgenic and Gene-Targeting Institutional Facility, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA
| | - Kristi L Jensen
- Faculty of Biology, Johannes Gutenberg University, 55099, Mainz, Germany
| | - Michaella J Levy
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- KCAS, 12400 Shawnee Mission Parkway, Shawnee, KS, 66216, USA
| | - Laurence Florens
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Peter Baumann
- Faculty of Biology, Johannes Gutenberg University, 55099, Mainz, Germany.
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA.
- Institute of Molecular Biology, Ackermannweg 4, 55128, Mainz, Germany.
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35
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Mishra S, Maraia RJ. Evolution of the RNA Cleavage Subunit C11/RPC10, and Recycling by RNA Polymerase III. JOURNAL OF CELLULAR IMMUNOLOGY 2022; 4:65-71. [PMID: 35813003 PMCID: PMC9262308 DOI: 10.33696/immunology.4.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Nuclear RNA polymerase (Pol) III synthesizes large amounts of tRNAs and other short non-coding (nc)RNAs by a unique process that involves a termination-associated reinitiation-recycling mechanism. In addition to its two largest of 17 subunits, which contribute to active center RNA-DNA binding and catalytic site, a smaller subunit of ~110 aa (yeast C11, human RPC10) monitors this site, can modify its activity, and is essential for reinitiation-recycling. Distinct, but relevant to human immunity is cytoplasmic (cyto-)Pol III that is a direct sensor of AT-rich viral DNA from which it synthesizes 5'-ppp-RNA signaling molecules that activate interferon (IFN) production. Mutations in genes encoding Pol III subunits cause severe anti-viral immunodeficiency although the mechanisms responsible for cyto-Pol III initiation on this AT-rich DNA are unknown. Cyto-Pol III has also been implicated in inducing IFN in response to cytosolic mitochondrial DNA in autoimmune dysfunction. A focus of this commentary is recent biochemical and genetics research that examined the roles of the individual domains of C11 in the Pol III termination-associated reinitiation-recycling process as well as more recent cryo-EM structural and accompanying analyses, that are considered in evolutionary and other biological contexts. The N-terminal domain (NTD) of C11/RPC10 anchors at the periphery of Pol III from which a highly conserved linker extends to the mobile C-terminal RNA cleavage domain that can reach into the active center and rescue arrested complexes. Biochemical data indicate separable activities for the NTD and CTD in the transcription cycle, whereas the NTD-Linker can confer the evolutionary unique Pol III termination-reinitiation-recycling activity. A model produced from single particle cryo-EM conformations indicates that the C11-Linker-CTD swings in and out of the active center coordinated with allosteric movements of the DNA-binding clamp by the largest subunit, coupling termination to reinitiation-recycling. These may be relevant to DNA loading by cyto-Pol III during immune signaling.
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Affiliation(s)
- Saurabh Mishra
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Richard J. Maraia
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD USA
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Yamazaki W, Badescu D, Tan SL, Ragoussis J, Taketo T. Effects of the Sex Chromosome Complement, XX, XO, or XY, on the Transcriptome and Development of Mouse Oocytes During Follicular Growth. Front Genet 2021; 12:792604. [PMID: 34987552 PMCID: PMC8721172 DOI: 10.3389/fgene.2021.792604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/26/2021] [Indexed: 12/26/2022] Open
Abstract
The sex chromosome complement, XX or XY, determines sexual differentiation of the gonadal primordium into a testis or an ovary, which in turn directs differentiation of the germ cells into sperm and oocytes, respectively, in eutherian mammals. When the X monosomy or XY sex reversal occurs, XO and XY females exhibit subfertility and infertility in the mouse on the C57BL/6J genetic background, suggesting that functional germ cell differentiation requires the proper sex chromosome complement. Using these mouse models, we asked how the sex chromosome complement affects gene transcription in the oocytes during follicular growth. An oocyte accumulates cytoplasmic components such as mRNAs and proteins during follicular growth to support subsequent meiotic progression, fertilization, and early embryonic development without de novo transcription. However, how gene transcription is regulated during oocyte growth is not well understood. Our results revealed that XY oocytes became abnormal in chromatin configuration, mitochondria distribution, and de novo transcription compared to XX or XO oocytes near the end of growth phase. Therefore, we compared transcriptomes by RNA-sequencing among the XX, XO, and XY oocytes of 50–60 µm in diameter, which were still morphologically comparable. The results showed that the X chromosome dosage limited the X-linked and autosomal gene transcript levels in XO oocytes whereas many genes were transcribed from the Y chromosome and made the transcriptome in XY oocytes closer to that in XX oocytes. We then compared the transcript levels of 3 X-linked, 3 Y-linked and 2 autosomal genes in the XX, XO, and XY oocytes during the entire growth phase as well as at the end of growth phase using quantitative RT-PCR. The results indicated that the transcript levels of most genes increased with oocyte growth while largely maintaining the X chromosome dosage dependence. Near the end of growth phase, however, transcript levels of some X-linked genes did not increase in XY oocytes as much as XX or XO oocytes, rendering their levels much lower than those in XX oocytes. Thus, XY oocytes established a distinct transcriptome at the end of growth phase, which may be associated with abnormal chromatin configuration and mitochondria distribution.
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Affiliation(s)
- Wataru Yamazaki
- Department of Surgery, McGill University, Montreal, QC, Canada
- Research Institute of McGill University Health Centre, Montreal, QC, Canada
| | - Dunarel Badescu
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- McGill University Genome Centre, Montreal, QC, Canada
| | - Seang Lin Tan
- Research Institute of McGill University Health Centre, Montreal, QC, Canada
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
- OriginElle Fertility Clinic and Women’s Health Centre, Montreal, QC, Canada
| | - Jiannis Ragoussis
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- McGill University Genome Centre, Montreal, QC, Canada
| | - Teruko Taketo
- Department of Surgery, McGill University, Montreal, QC, Canada
- Research Institute of McGill University Health Centre, Montreal, QC, Canada
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
- Department of Biology, McGill University, Montreal, QC, Canada
- *Correspondence: Teruko Taketo,
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Kessler AC, Maraia RJ. The nuclear and cytoplasmic activities of RNA polymerase III, and an evolving transcriptome for surveillance. Nucleic Acids Res 2021; 49:12017-12034. [PMID: 34850129 PMCID: PMC8643620 DOI: 10.1093/nar/gkab1145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/26/2021] [Accepted: 11/02/2021] [Indexed: 12/23/2022] Open
Abstract
A 1969 report that described biochemical and activity properties of the three eukaryotic RNA polymerases revealed Pol III as highly distinguishable, even before its transcripts were identified. Now known to be the most complex, Pol III contains several stably-associated subunits referred to as built-in transcription factors (BITFs) that enable highly efficient RNA synthesis by a unique termination-associated recycling process. In vertebrates, subunit RPC7(α/β) can be of two forms, encoded by POLR3G or POLR3GL, with differential activity. Here we review promoter-dependent transcription by Pol III as an evolutionary perspective of eukaryotic tRNA expression. Pol III also provides nonconventional functions reportedly by promoter-independent transcription, one of which is RNA synthesis from DNA 3'-ends during repair. Another is synthesis of 5'ppp-RNA signaling molecules from cytoplasmic viral DNA in a pathway of interferon activation that is dysfunctional in immunocompromised patients with mutations in Pol III subunits. These unconventional functions are also reviewed, including evidence that link them to the BITF subunits. We also review data on a fraction of the human Pol III transcriptome that evolved to include vault RNAs and snaRs with activities related to differentiation, and in innate immune and tumor surveillance. The Pol III of higher eukaryotes does considerably more than housekeeping.
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Affiliation(s)
- Alan C Kessler
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892 USA
| | - Richard J Maraia
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892 USA
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Ha N, Ding N, Hong R, Liu R, Roca X, Luo Y, Duan X, Wang X, Ni P, Wu H, Zhang LF, Chen L. The lupus autoantigen La/Ssb is an Xist-binding protein involved in Xist folding and cloud formation. Nucleic Acids Res 2021; 49:11596-11613. [PMID: 34723322 PMCID: PMC8599922 DOI: 10.1093/nar/gkab1003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 08/25/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
Using the programmable RNA-sequence binding domain of the Pumilio protein, we FLAG-tagged Xist (inactivated X chromosome specific transcript) in live mouse cells. Affinity pulldown coupled to mass spectrometry was employed to identify a list of 138 candidate Xist-binding proteins, from which, Ssb (also known as the lupus autoantigen La) was validated as a protein functionally critical for X chromosome inactivation (XCI). Extensive XCI defects were detected in Ssb knockdown cells, including chromatin compaction, death of female mouse embryonic stem cells during in vitro differentiation and chromosome-wide monoallelic gene expression pattern. Live-cell imaging of Xist RNA reveals the defining XCI defect: Xist cloud formation. Ssb is a ubiquitous and versatile RNA-binding protein with RNA chaperone and RNA helicase activities. Functional dissection of Ssb shows that the RNA chaperone domain plays critical roles in XCI. In Ssb knockdown cells, Xist transcripts are unstable and misfolded. These results show that Ssb is critically involved in XCI, possibly as a protein regulating the in-cell structure of Xist.
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Affiliation(s)
- Norbert Ha
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Nan Ding
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Ru Hong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Rubing Liu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Xavier Roca
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Yingyuan Luo
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xiaowei Duan
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xiao Wang
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Peiling Ni
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Haiyang Wu
- TCRCure Biological Technology Co Ltd., Guangdong, China
| | - Li-Feng Zhang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
- TCRCure Biological Technology Co Ltd., Guangdong, China
| | - Lingyi Chen
- Institute of Translational Medicine, Tianjin Union Medical Center, State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center for Biotherapy, Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Protein Sciences, National Demonstration Center for Experimental Biology Education and College of Life Sciences, Nankai University, Tianjin 300071, China
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Bousquet-Antonelli C. LARP6 proteins in plants. Biochem Soc Trans 2021; 49:1975-1983. [PMID: 34709399 DOI: 10.1042/bst20200715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 11/17/2022]
Abstract
RNA binding proteins, through control of mRNA fate and expression, are key players of organism development. The LARP family of RBPs sharing the La motif, are largely present in eukaryotes. They classify into five subfamilies which members acquired specific additional domains, including the RRM1 moiety which teams up with the La motif to form a versatile RNA binding unit. The LARP6 subfamily has had a peculiar history during plant evolution. While containing a single LARP6 in algae and non-vascular plants, they expanded and neofunctionalized into three subclusters in vascular plants. Studies from Arabidopsis thaliana, support that they acquired specific RNA binding properties and physiological roles. In particular LARP6C participates, through spatiotemporal control of translation, to male fertilization, a role seemingly conserved in maize. Interestingly, human LARP6 also acts in translation control and mRNA transport and similarly to LARP6C which is required for pollen tube guided elongation, is necessary to cell migration, through protrusion extension. This opens the possibility that some cellular and molecular functions of LARP6 were retained across eukaryote evolution. With their peculiar evolutionary history, plants provide a unique opportunity to uncover how La-module RNA binding properties evolved and identify species specific and basal roles of the LARP6 function. Deciphering of how LARP6, in particular LARP6C, acts at the molecular level, will foster novel knowledge on translation regulation and dynamics in changing cellular contexts. Considering the seemingly conserved function of LARP6C in male reproduction, it should fuel studies aimed at deriving crop species with improved seed yields.
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Affiliation(s)
- Cécile Bousquet-Antonelli
- CNRS LGDP-UMR5096, 58 Av. Paul Alduy, 66860 Perpignan, France
- Université de Perpignan Via Domitia, LGDP-UMR5096, 58 Av. Paul Alduy, 66860 Perpignan, France
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40
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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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41
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Berndt N, Bippes CC, Michalk I, Bartsch T, Arndt C, Puentes-Cala E, Soto JA, Loureiro LR, Kegler A, Bachmann D, Gross JK, Gross T, Kurien BT, Scofield RH, Farris AD, James JA, Bergmann R, Schmitz M, Feldmann A, Bachmann MP. And Yet It Moves: Oxidation of the Nuclear Autoantigen La/SS-B Is the Driving Force for Nucleo-Cytoplasmic Shuttling. Int J Mol Sci 2021; 22:9699. [PMID: 34575862 PMCID: PMC8470643 DOI: 10.3390/ijms22189699] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 01/10/2023] Open
Abstract
Decades ago, we and many other groups showed a nucleo-cytoplasmic translocation of La protein in cultured cells. This shuttling of La protein was seen after UV irradiation, virus infections, hydrogen peroxide exposure and the Fenton reaction based on iron or copper ions. All of these conditions are somehow related to oxidative stress. Unfortunately, these harsh conditions could also cause an artificial release of La protein. Even until today, the shuttling and the cytoplasmic function of La/SS-B is controversially discussed. Moreover, the driving mechanism for the shuttling of La protein remains unclear. Recently, we showed that La protein undergoes redox-dependent conformational changes. Moreover, we developed anti-La monoclonal antibodies (anti-La mAbs), which are specific for either the reduced form of La protein or the oxidized form. Using these tools, here we show that redox-dependent conformational changes are the driving force for the shuttling of La protein. Moreover, we show that translocation of La protein to the cytoplasm can be triggered in a ligand/receptor-dependent manner under physiological conditions. We show that ligands of toll-like receptors lead to a redox-dependent shuttling of La protein. The shuttling of La protein depends on the redox status of the respective cell type. Endothelial cells are usually resistant to the shuttling of La protein, while dendritic cells are highly sensitive. However, the deprivation of intracellular reducing agents in endothelial cells makes endothelial cells sensitive to a redox-dependent shuttling of La protein.
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Affiliation(s)
- Nicole Berndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Claudia C. Bippes
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technische Universität Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
| | - Irene Michalk
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technische Universität Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
| | - Tabea Bartsch
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Claudia Arndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Edinson Puentes-Cala
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
- Corporación para la Investigación de la Corrosión (CIC), Piedecuesta 681011, Colombia
| | - Javier Andrés Soto
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
- Instituto de Investigación Masira, Facultad de Ciencias Médicas y de la Salud, Universidad de Santander, Cúcuta 540001, Colombia
| | - Liliana R. Loureiro
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Alexandra Kegler
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Dominik Bachmann
- Tumor Immunology, University Cancer Center (UCC), University Hospital Carl Gustav Carus Technische Universität Dresden, 01307 Dresden, Germany;
| | - Joanne K. Gross
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Tim Gross
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Biji T. Kurien
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - R. Hal Scofield
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - A. Darise Farris
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Judith A. James
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Ralf Bergmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
- Department of Biophysics and Radiobiology, Semmelweis University, 1094 Budapest, Hungary
| | - Marc Schmitz
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technische Universität Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
- National Center for Tumor Diseases (NCT), 03128 Dresden, Germany
| | - Anja Feldmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
| | - Michael P. Bachmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (T.B.); (C.A.); (E.P.-C.); (J.A.S.); (L.R.L.); (A.K.); (R.B.); (A.F.)
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technische Universität Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
- National Center for Tumor Diseases (NCT), 03128 Dresden, Germany
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Billey E, Hafidh S, Cruz-Gallardo I, Litholdo CG, Jean V, Carpentier MC, Picart C, Kumar V, Kulichova K, Maréchal E, Honys D, Conte MR, Deragon JM, Bousquet-Antonelli C. LARP6C orchestrates posttranscriptional reprogramming of gene expression during hydration to promote pollen tube guidance. THE PLANT CELL 2021; 33:2637-2661. [PMID: 34124761 PMCID: PMC8408461 DOI: 10.1093/plcell/koab131] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 05/06/2021] [Indexed: 05/15/2023]
Abstract
Increasing evidence suggests that posttranscriptional regulation is a key player in the transition between mature pollen and the progamic phase (from pollination to fertilization). Nonetheless, the actors in this messenger RNA (mRNA)-based gene expression reprogramming are poorly understood. We demonstrate that the evolutionarily conserved RNA-binding protein LARP6C is necessary for the transition from dry pollen to pollen tubes and the guided growth of pollen tubes towards the ovule in Arabidopsis thaliana. In dry pollen, LARP6C binds to transcripts encoding proteins that function in lipid synthesis and homeostasis, vesicular trafficking, and polarized cell growth. LARP6C also forms cytoplasmic granules that contain the poly(A) binding protein and possibly represent storage sites for translationally silent mRNAs. In pollen tubes, the loss of LARP6C negatively affects the quantities and distribution of storage lipids, as well as vesicular trafficking. In Nicotiana benthamiana leaf cells and in planta, analysis of reporter mRNAs designed from the LARP6C target MGD2 provided evidence that LARP6C can shift from a repressor to an activator of translation when the pollen grain enters the progamic phase. We propose that LARP6C orchestrates the timely posttranscriptional regulation of a subset of mRNAs in pollen during the transition from the quiescent to active state and along the progamic phase to promote male fertilization in plants.
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Affiliation(s)
- Elodie Billey
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Said Hafidh
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Isabel Cruz-Gallardo
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Celso G. Litholdo
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Viviane Jean
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Marie-Christine Carpentier
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Claire Picart
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Vinod Kumar
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Katarina Kulichova
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168 CNRS, CEA, INRAE, Université Grenoble Alpes, IRIG, CEA Grenoble, 38054 Grenoble, France
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Maria R. Conte
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Jean-Marc Deragon
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
- Institut Universitaire de France, 75231 Paris Cedex 5, France
| | - Cécile Bousquet-Antonelli
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
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Billey E, Hafidh S, Cruz-Gallardo I, Litholdo CG, Jean V, Carpentier MC, Picart C, Kumar V, Kulichova K, Maréchal E, Honys D, Conte MR, Deragon JM, Bousquet-Antonelli C. LARP6C orchestrates posttranscriptional reprogramming of gene expression during hydration to promote pollen tube guidance. THE PLANT CELL 2021; 33:2637-2661. [PMID: 34124761 DOI: 10.1101/2020.11.27.401307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 05/06/2021] [Indexed: 05/19/2023]
Abstract
Increasing evidence suggests that posttranscriptional regulation is a key player in the transition between mature pollen and the progamic phase (from pollination to fertilization). Nonetheless, the actors in this messenger RNA (mRNA)-based gene expression reprogramming are poorly understood. We demonstrate that the evolutionarily conserved RNA-binding protein LARP6C is necessary for the transition from dry pollen to pollen tubes and the guided growth of pollen tubes towards the ovule in Arabidopsis thaliana. In dry pollen, LARP6C binds to transcripts encoding proteins that function in lipid synthesis and homeostasis, vesicular trafficking, and polarized cell growth. LARP6C also forms cytoplasmic granules that contain the poly(A) binding protein and possibly represent storage sites for translationally silent mRNAs. In pollen tubes, the loss of LARP6C negatively affects the quantities and distribution of storage lipids, as well as vesicular trafficking. In Nicotiana benthamiana leaf cells and in planta, analysis of reporter mRNAs designed from the LARP6C target MGD2 provided evidence that LARP6C can shift from a repressor to an activator of translation when the pollen grain enters the progamic phase. We propose that LARP6C orchestrates the timely posttranscriptional regulation of a subset of mRNAs in pollen during the transition from the quiescent to active state and along the progamic phase to promote male fertilization in plants.
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Affiliation(s)
- Elodie Billey
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Said Hafidh
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Isabel Cruz-Gallardo
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Celso G Litholdo
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Viviane Jean
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Marie-Christine Carpentier
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Claire Picart
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Vinod Kumar
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Katarina Kulichova
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168 CNRS, CEA, INRAE, Université Grenoble Alpes, IRIG, CEA Grenoble, 38054 Grenoble, France
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Prague 6, Czech Republic
| | - Maria R Conte
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Jean-Marc Deragon
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
- Institut Universitaire de France, 75231 Paris Cedex 5, France
| | - Cécile Bousquet-Antonelli
- Laboratoire Génome et Développement des Plantes, UMR5096, CNRS, 66860 Perpignan, France
- Laboratoire Génome et Développement des Plantes, UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
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Nagano S, Araki T. Axonal Transport and Local Translation of mRNA in Neurodegenerative Diseases. Front Mol Neurosci 2021; 14:697973. [PMID: 34194300 PMCID: PMC8236635 DOI: 10.3389/fnmol.2021.697973] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/25/2021] [Indexed: 12/13/2022] Open
Abstract
Since neurons have long neurites including axons, it is crucial for the axons to transport many intracellular substances such as proteins and mitochondria in order to maintain their morphology and function. In addition, mRNAs have also been shown to be transported within axons. RNA-binding proteins form complexes with mRNAs, and regulate transport of the mRNAs to axons, as well as locally translate them into proteins. Local translation of mRNAs actively occurs during the development and damage of neurons, and plays an important role in axon elongation, regeneration, and synapse formation. In recent years, it has been reported that impaired axonal transport and local translation of mRNAs may be involved in the pathogenesis of some neurodegenerative diseases. In this review, we discuss the significance of mRNA axonal transport and their local translation in amyotrophic lateral sclerosis/frontotemporal dementia, spinal muscular atrophy, Alzheimer’s disease, and fragile X syndrome.
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Affiliation(s)
- Seiichi Nagano
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan.,Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Toshiyuki Araki
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
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46
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Structures of telomerase at several steps of telomere repeat synthesis. Nature 2021; 593:454-459. [PMID: 33981033 DOI: 10.1038/s41586-021-03529-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 04/09/2021] [Indexed: 12/14/2022]
Abstract
Telomerase is unique among the reverse transcriptases in containing a noncoding RNA (known as telomerase RNA (TER)) that includes a short template that is used for the processive synthesis of G-rich telomeric DNA repeats at the 3' ends of most eukaryotic chromosomes1. Telomerase maintains genomic integrity, and its activity or dysregulation are critical determinants of human longevity, stem cell renewal and cancer progression2,3. Previous cryo-electron microscopy structures have established the general architecture, protein components and stoichiometries of Tetrahymena and human telomerase, but our understandings of the details of DNA-protein and RNA-protein interactions and of the mechanisms and recruitment involved remain limited4-6. Here we report cryo-electron microscopy structures of active Tetrahymena telomerase with telomeric DNA at different steps of nucleotide addition. Interactions between telomerase reverse transcriptase (TERT), TER and DNA reveal the structural basis of the determination of the 5' and 3' template boundaries, handling of the template-DNA duplex and separation of the product strand during nucleotide addition. The structure and binding interface between TERT and telomerase protein p50 (a homologue of human TPP17,8) define conserved interactions that are required for telomerase activation and recruitment to telomeres. Telomerase La-related protein p65 remodels several regions of TER, bridging the 5' and 3' ends and the conserved pseudoknot to facilitate assembly of the TERT-TER catalytic core.
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Berndt N, Bippes CC, Michalk I, Bachmann D, Bachmann J, Puentes-Cala E, Bartsch T, Loureiro LR, Kegler A, Bergmann R, Gross JK, Gross T, Kurien BT, Scofield RH, Farris AD, James JA, Schmitz M, Fahmy K, Feldmann A, Arndt C, Bachmann MP. Two Be or Not Two Be: The Nuclear Autoantigen La/SS-B Is Able to Form Dimers and Oligomers in a Redox Dependent Manner. Int J Mol Sci 2021; 22:3377. [PMID: 33806091 PMCID: PMC8036718 DOI: 10.3390/ijms22073377] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/17/2021] [Accepted: 03/22/2021] [Indexed: 12/14/2022] Open
Abstract
According to the literature, the autoantigen La is involved in Cap-independent translation. It was proposed that one prerequisite for this function is the formation of a protein dimer. However, structural analyses argue against La protein dimers. Noteworthy to mention, these structural analyses were performed under reducing conditions. Here we describe that La protein can undergo redox-dependent structural changes. The oxidized form of La protein can form dimers, oligomers and even polymers stabilized by disulfide bridges. The primary sequence of La protein contains three cysteine residues. Only after mutation of all three cysteine residues to alanine La protein becomes insensitive to oxidation, indicating that all three cysteines are involved in redox-dependent structural changes. Biophysical analyses of the secondary structure of La protein support the redox-dependent conformational changes. Moreover, we identified monoclonal anti-La antibodies (anti-La mAbs) that react with either the reduced or oxidized form of La protein. Differential reactivities to the reduced and oxidized form of La protein were also found in anti-La sera of autoimmune patients.
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Affiliation(s)
- Nicole Berndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Claudia C. Bippes
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
| | - Irene Michalk
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
| | - Dominik Bachmann
- University Cancer Center (UCC), Tumor Immunology, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (D.B.); (J.B.)
| | - Jennifer Bachmann
- University Cancer Center (UCC), Tumor Immunology, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (D.B.); (J.B.)
| | - Edinson Puentes-Cala
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
- Corporación para la Investigación de la Corrosión (CIC), Piedecuesta 681011, Colombia
| | - Tabea Bartsch
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Liliana R. Loureiro
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Alexandra Kegler
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Ralf Bergmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
- Department of Biophysics and Radiobiology, Semmelweis University, 1094 Budapest, Hungary
| | - Joanne K. Gross
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Tim Gross
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Biji T. Kurien
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - R. Hal Scofield
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - A. Darise Farris
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Judith A. James
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.K.G.); (T.G.); (B.T.K.); (R.H.S.); (A.D.F.); (J.A.J.)
| | - Marc Schmitz
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
- National Center for Tumor Diseases (NCT), 01307 Dresden, Germany
| | - Karim Fahmy
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany;
| | - Anja Feldmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Claudia Arndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
| | - Michael P. Bachmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (N.B.); (E.P.-C.); (T.B.); (L.R.L.); (A.K.); (R.B.); (A.F.); (C.A.)
- Institute of Immunology, Medical Faculty Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (C.C.B.); (I.M.); (M.S.)
- University Cancer Center (UCC), Tumor Immunology, University Hospital Carl Gustav Carus Dresden, Technical University Dresden, 01307 Dresden, Germany; (D.B.); (J.B.)
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Zhou L, Vejlupkova Z, Warman C, Fowler JE. A Maize Male Gametophyte-Specific Gene Encodes ZmLARP6c1, a Potential RNA-Binding Protein Required for Competitive Pollen Tube Growth. FRONTIERS IN PLANT SCIENCE 2021; 12:635244. [PMID: 33719310 PMCID: PMC7947365 DOI: 10.3389/fpls.2021.635244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
Members of the La-related protein family (LARPs) contain a conserved La module, which has been associated with RNA-binding activity. Expression of the maize gene GRMZM2G323499/Zm00001d018613, a member of the LARP family, is highly specific to pollen, based on both transcriptomic and proteomic assays. This suggests a pollen-specific RNA regulatory function for the protein, designated ZmLARP6c1 based on sequence similarity to the LARP6 subfamily in Arabidopsis. To test this hypothesis, a Ds-GFP transposable element insertion in the ZmLarp6c1 gene (tdsgR82C05) was obtained from the Dooner/Du mutant collection. Sequencing confirmed that the Ds-GFP insertion is in an exon, and thus likely interferes with ZmLARP6c1 function. Tracking inheritance of the insertion via its endosperm-expressed GFP indicated that the mutation was associated with reduced transmission from a heterozygous plant when crossed as a male (ranging from 0.5 to 26.5% transmission), but not as a female. Furthermore, this transmission defect was significantly alleviated when less pollen was applied to the silk, reducing competition between mutant and wild-type pollen. Pollen grain diameter measurements and nuclei counts showed no significant differences between wild-type and mutant pollen. However, in vitro, mutant pollen tubes were significantly shorter than those from sibling wild-type plants, and also displayed altered germination dynamics. These results are consistent with the idea that ZmLARP6c1 provides an important regulatory function during the highly competitive progamic phase of male gametophyte development following arrival of the pollen grain on the silk. The conditional, competitive nature of the Zmlarp6c1::Ds male sterility phenotype (i.e., reduced ability to produce progeny seed) points toward new possibilities for genetic control of parentage in crop production.
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Affiliation(s)
- Lian Zhou
- Maize Research Institute, College of Agronomy and Biotechnology, Southwest University, Chongqing, China
| | - Zuzana Vejlupkova
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Cedar Warman
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - John E Fowler
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
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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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50
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Berman AJ, Thoreen CC, Dedeic Z, Chettle J, Roux PP, Blagden SP. Controversies around the function of LARP1. RNA Biol 2021; 18:207-217. [PMID: 32233986 PMCID: PMC7928164 DOI: 10.1080/15476286.2020.1733787] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/06/2020] [Accepted: 02/11/2020] [Indexed: 12/21/2022] Open
Abstract
The RNA-binding protein LARP1 has generated interest in recent years for its role in the mTOR signalling cascade and its regulation of terminal oligopyrimidine (TOP) mRNA translation. Paradoxically, some scientists have shown that LARP1 represses TOP translation while others that LARP1 activates it. Here, we present opinions from four leading scientists in the field to discuss these and other contradictory findings.
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Affiliation(s)
- Andrea J. Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, USA
| | - Carson C. Thoreen
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, USA
| | - Zinaida Dedeic
- Department of Oncology, University of Oxford, Oxford, UK
| | - James Chettle
- Department of Oncology, University of Oxford, Oxford, UK
| | - Philippe P. Roux
- Institute for Research in Immunology and Cancer (IRIC), Université De Montréal, Montreal, Quebec, Canada
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