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Phillips-Rose LS, Yu CK, West NP, Fraser JA. A Chimeric ORF Fusion Phenotypic Reporter for Cryptococcus neoformans. J Fungi (Basel) 2024; 10:567. [PMID: 39194893 DOI: 10.3390/jof10080567] [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: 07/09/2024] [Revised: 08/05/2024] [Accepted: 08/07/2024] [Indexed: 08/29/2024] Open
Abstract
The plethora of genome sequences produced in the postgenomic age has not resolved many of our most pressing biological questions. Correlating gene expression with an interrogatable and easily observable characteristic such as the surrogate phenotype conferred by a reporter gene is a valuable approach to gaining insight into gene function. Many reporters including lacZ, amdS, and the fluorescent proteins mRuby3 and mNeonGreen have been used across all manners of organisms. Described here is an investigation into the creation of a robust, synthetic, fusion reporter system for Cryptococcus neoformans that combines some of the most useful fluorophores available in this system with the versatility of the counter-selectable nature of amdS. The reporters generated include multiple composition and orientation variants, all of which were investigated for differences in expression. Evaluation of known promoters from the TEF1 and GAL7 genes was undertaken, elucidating novel expression tendencies of these biologically relevant C. neoformans regulators of transcription. Smaller than lacZ but providing multiple useful surrogate phenotypes for interrogation, the fusion ORF serves as a superior whole-cell assay compared to traditional systems. Ultimately, the work described here bolsters the array of relevant genetic tools that may be employed in furthering manipulation and understanding of the WHO fungal priority group pathogen C. neoformans.
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Affiliation(s)
- Louis S Phillips-Rose
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Chendi K Yu
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Nicholas P West
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - James A Fraser
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
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2
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Akirtava C, May G, McManus CJ. Deciphering the cis-regulatory landscape of natural yeast Transcript Leaders. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.03.601937. [PMID: 39005336 PMCID: PMC11245039 DOI: 10.1101/2024.07.03.601937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Protein synthesis is a vital process that is highly regulated at the initiation step of translation. Eukaryotic 5' transcript leaders (TLs) contain a variety of cis-regulatory features that influence translation and mRNA stability. However, the relative influences of these features in natural TLs are poorly characterized. To address this, we used massively parallel reporter assays (MPRAs) to quantify RNA levels, ribosome loading, and protein levels from 11,027 natural yeast TLs in vivo and systematically compared the relative impacts of their sequence features on gene expression. We found that yeast TLs influence gene expression over two orders of magnitude. While a leaky scanning model using Kozak contexts and uAUGs explained half of the variance in expression across transcript leaders, the addition of other features explained ~70% of gene expression variation. Our analyses detected key cis-acting sequence features, quantified their effects in vivo, and compared their roles to motifs reported from an in vitro study of ribosome recruitment. In addition, our work quantitated the effects of alternative transcription start site usage on gene expression in yeast. Thus, our study provides new quantitative insights into the roles of TL cis-acting sequences in regulating gene expression.
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Affiliation(s)
- Christina Akirtava
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
- RNA Bioscience Initiative, University of Colorado - Anshutz, Aurora, CO, 80045, USA
| | - Gemma May
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - C Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
- Computational Biology Department, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
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3
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Dang TTV, Maufrais C, Colin J, Moyrand F, Mouyna I, Coppée JY, Onyishi CU, Lipecka J, Guerrera IC, May RC, Janbon G. Alternative TSS use is widespread in Cryptococcus fungi in response to environmental cues and regulated genome-wide by the transcription factor Tur1. PLoS Biol 2024; 22:e3002724. [PMID: 39052688 PMCID: PMC11302930 DOI: 10.1371/journal.pbio.3002724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/06/2024] [Accepted: 06/28/2024] [Indexed: 07/27/2024] Open
Abstract
Alternative transcription start site (TSS) usage regulation has been identified as a major means of gene expression regulation in metazoans. However, in fungi, its impact remains elusive as its study has thus far been restricted to model yeasts. Here, we first re-analyzed TSS-seq data to define genuine TSS clusters in 2 species of pathogenic Cryptococcus. We identified 2 types of TSS clusters associated with specific DNA sequence motifs. Our analysis also revealed that alternative TSS usage regulation in response to environmental cues is widespread in Cryptococcus, altering gene expression and protein targeting. Importantly, we performed a forward genetic screen to identify a unique transcription factor (TF) named Tur1, which regulates alternative TSS (altTSS) usage genome-wide when cells switch from exponential phase to stationary phase. ChiP-Seq and DamID-Seq analyses suggest that at some loci, the role of Tur1 might be direct. Tur1 has been previously shown to be essential for virulence in C. neoformans. We demonstrated here that a tur1Δ mutant strain is more sensitive to superoxide stress and phagocytosed more efficiently by macrophages than the wild-type (WT) strain.
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Affiliation(s)
- Thi Tuong Vi Dang
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
| | - Corinne Maufrais
- Université Paris Cité, Institut Pasteur, HUB Bioinformatique et Biostatistique, C3BI, USR 3756 IP CNRS, Paris, France
| | - Jessie Colin
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, Paris, France
| | - Frédérique Moyrand
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
| | - Isabelle Mouyna
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
| | - Jean-Yves Coppée
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
| | - Chinaemerem U. Onyishi
- Institute of Microbiology and Infection and School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Joanna Lipecka
- Université Paris Cité, SFR Necker INSERM US24/CNRS UAR3633, Proteomics Platform, Paris, France
| | - Ida Chiara Guerrera
- Université Paris Cité, SFR Necker INSERM US24/CNRS UAR3633, Proteomics Platform, Paris, France
| | - Robin C. May
- Institute of Microbiology and Infection and School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Guilhem Janbon
- Université Paris Cité, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Paris, France
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4
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Hughes ES, Tuck LR, He Z, Ballou ER, Wallace EWJ. A trade-off between proliferation and defense in the fungal pathogen Cryptococcus at alkaline pH is controlled by the transcription factor GAT201. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.14.543486. [PMID: 37398450 PMCID: PMC10312749 DOI: 10.1101/2023.06.14.543486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Cryptococcus is a fungal pathogen whose virulence relies on proliferation in and dissemination to host sites, and on synthesis of a defensive yet metabolically costly polysaccharide capsule. Regulatory pathways required for Cryptococcus virulence include a GATA-like transcription factor, Gat201, that regulates Cryptococcal virulence in both capsule-dependent and capsule-independent ways. Here we show that Gat201 is part of a negative regulatory pathway that limits fungal survival at alkaline pH. RNA-seq analysis found strong induction of GAT201 expression within minutes of transfer to RPMI media at alkaline pH. Microscopy, growth curves, and colony forming unit assays show that in RPMI at alkaline pH wild-type Cryptococcus neoformans yeast cells produce capsule but do not bud or maintain viability, while gat201Δ cells make buds and maintain viability, yet fail to produce capsule. GAT201 is required for transcriptional upregulation of a specific set of genes, the majority of which are direct Gat201 targets. Evolutionary analysis shows that Gat201 is in a subfamily of GATA-like transcription factors that is conserved within pathogenic fungi but absent in model yeasts. This work identifies the Gat201 pathway as controlling a trade-off between proliferation and production of defensive capsule. The assays established here will allow characterisation of the mechanisms of action of the Gat201 pathway. Together, our findings urge improved understanding of the regulation of proliferation as a driver of fungal pathogenesis.
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Affiliation(s)
- Elizabeth S Hughes
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | - Laura R Tuck
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | - Zhenzhen He
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | | | - Edward W J Wallace
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
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5
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Oberegger S, Misslinger M, Faserl K, Sarg B, Farhan H, Haas H. The cytosolic form of dual localized BolA family protein Bol3 is important for adaptation to iron starvation in Aspergillus fumigatus. Open Biol 2024; 14:240033. [PMID: 38919062 DOI: 10.1098/rsob.240033] [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: 02/08/2024] [Accepted: 04/23/2024] [Indexed: 06/27/2024] Open
Abstract
Aspergillus fumigatus is the predominant mould pathogen for humans. Adaption to host-imposed iron limitation has previously been demonstrated to be essential for its virulence. [2Fe-2S] clusters are crucial as cofactors of several metabolic pathways and mediate cytosolic/nuclear iron sensing in fungi including A. fumigatus. [2Fe-2S] cluster trafficking has been shown to involve BolA family proteins in both mitochondria and the cytosol/nucleus. Interestingly, both A. fumigatus homologues, termed Bol1 and Bol3, possess mitochondrial targeting sequences, suggesting the lack of cytosolic/nuclear versions. Here, we show by the combination of mutational, proteomic and fluorescence microscopic analyses that expression of the Bol3 encoding gene leads to dual localization of gene products to mitochondria and the cytosol/nucleus via alternative translation initiation downstream of the mitochondrial targeting sequence, which appears to be highly conserved in various Aspergillus species. Lack of either mitochondrial Bol1 or Bol3 was phenotypically inconspicuous while lack of cytosolic/nuclear Bol3 impaired growth during iron limitation but not iron sensing which indicates a particular importance of [2Fe-2S] cluster trafficking during iron limitation. Remarkably, cytosolic/nuclear Bol3 differs from the mitochondrial version only by N-terminal acetylation, a finding that was only possible by mutational hypothesis testing.
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Affiliation(s)
- Simon Oberegger
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Matthias Misslinger
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Klaus Faserl
- Institute of Medical Biochemistry, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Bettina Sarg
- Institute of Medical Biochemistry, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Hesso Farhan
- Institute of Pathophysiology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Hubertus Haas
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
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6
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Hernández G, García A, Weingarten-Gabbay S, Mishra R, Hussain T, Amiri M, Moreno-Hagelsieb G, Montiel-Dávalos A, Lasko P, Sonenberg N. Functional analysis of the AUG initiator codon context reveals novel conserved sequences that disfavor mRNA translation in eukaryotes. Nucleic Acids Res 2024; 52:1064-1079. [PMID: 38038264 PMCID: PMC10853783 DOI: 10.1093/nar/gkad1152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 11/09/2023] [Accepted: 11/15/2023] [Indexed: 12/02/2023] Open
Abstract
mRNA translation is a fundamental process for life. Selection of the translation initiation site (TIS) is crucial, as it establishes the correct open reading frame for mRNA decoding. Studies in vertebrate mRNAs discovered that a purine at -3 and a G at +4 (where A of the AUG initiator codon is numbered + 1), promote TIS recognition. However, the TIS context in other eukaryotes has been poorly experimentally analyzed. We analyzed in vitro the influence of the -3, -2, -1 and + 4 positions of the TIS context in rabbit, Drosophila, wheat, and yeast. We observed that -3A conferred the best translational efficiency across these species. However, we found variability at the + 4 position for optimal translation. In addition, the Kozak motif that was defined from mammalian cells was only weakly predictive for wheat and essentially non-predictive for yeast. We discovered eight conserved sequences that significantly disfavored translation. Due to the big differences in translational efficiency observed among weak TIS context sequences, we define a novel category that we termed 'barren AUG context sequences (BACS)', which represent sequences disfavoring translation. Analysis of mRNA-ribosomal complexes structures provided insights into the function of BACS. The gene ontology of the BACS-containing mRNAs is presented.
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Affiliation(s)
- Greco Hernández
- mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (INCan), Mexico City 14080, Mexico
| | - Alejandra García
- mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (INCan), Mexico City 14080, Mexico
| | - Shira Weingarten-Gabbay
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY, USA
| | - Rishi Kumar Mishra
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru-560012, India
| | - Tanweer Hussain
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru-560012, India
| | - Mehdi Amiri
- Department of Biochemistry and Goodman Cancer Institute. McGill University., Montreal, QC H3A 1A3, Canada
| | - Gabriel Moreno-Hagelsieb
- Department of Biology, Wilfrid Laurier University. 75 University Ave. W, Waterloo, ON N2L 3C5, Canada
| | - Angélica Montiel-Dávalos
- mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (INCan), Mexico City 14080, Mexico
| | - Paul Lasko
- Department of Biology, McGill University. Montreal, QC H3G 0B1, Canada
| | - Nahum Sonenberg
- Department of Biochemistry and Goodman Cancer Institute. McGill University., Montreal, QC H3A 1A3, Canada
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7
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O'Meara MJ, Rapala JR, Nichols CB, Alexandre AC, Billmyre RB, Steenwyk JL, Alspaugh JA, O'Meara TR. CryptoCEN: A Co-Expression Network for Cryptococcus neoformans reveals novel proteins involved in DNA damage repair. PLoS Genet 2024; 20:e1011158. [PMID: 38359090 PMCID: PMC10901339 DOI: 10.1371/journal.pgen.1011158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/28/2024] [Accepted: 01/30/2024] [Indexed: 02/17/2024] Open
Abstract
Elucidating gene function is a major goal in biology, especially among non-model organisms. However, doing so is complicated by the fact that molecular conservation does not always mirror functional conservation, and that complex relationships among genes are responsible for encoding pathways and higher-order biological processes. Co-expression, a promising approach for predicting gene function, relies on the general principal that genes with similar expression patterns across multiple conditions will likely be involved in the same biological process. For Cryptococcus neoformans, a prevalent human fungal pathogen greatly diverged from model yeasts, approximately 60% of the predicted genes in the genome lack functional annotations. Here, we leveraged a large amount of publicly available transcriptomic data to generate a C. neoformans Co-Expression Network (CryptoCEN), successfully recapitulating known protein networks, predicting gene function, and enabling insights into the principles influencing co-expression. With 100% predictive accuracy, we used CryptoCEN to identify 13 new DNA damage response genes, underscoring the utility of guilt-by-association for determining gene function. Overall, co-expression is a powerful tool for uncovering gene function, and decreases the experimental tests needed to identify functions for currently under-annotated genes.
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Affiliation(s)
- Matthew J O'Meara
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jackson R Rapala
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Connie B Nichols
- Departments of Medicine and Molecular Genetics/Microbiology; and Cell Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - A Christina Alexandre
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - R Blake Billmyre
- Departments of Pharmaceutical and Biomedical Sciences/Infectious Disease, College of Pharmacy/College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America
| | - Jacob L Steenwyk
- Howard Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, United States of America
| | - J Andrew Alspaugh
- Departments of Medicine and Molecular Genetics/Microbiology; and Cell Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Teresa R O'Meara
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
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8
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Rizzo J, Trottier A, Moyrand F, Coppée JY, Maufrais C, Zimbres ACG, Dang TTV, Alanio A, Desnos-Ollivier M, Mouyna I, Péhau-Arnaude G, Commere PH, Novault S, Ene IV, Nimrichter L, Rodrigues ML, Janbon G. Coregulation of extracellular vesicle production and fluconazole susceptibility in Cryptococcus neoformans. mBio 2023; 14:e0087023. [PMID: 37310732 PMCID: PMC10470540 DOI: 10.1128/mbio.00870-23] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 04/17/2023] [Indexed: 06/14/2023] Open
Abstract
Resistance to fluconazole (FLC), the most widely used antifungal drug, is typically achieved by altering the azole drug target and/or drug efflux pumps. Recent reports have suggested a link between vesicular trafficking and antifungal resistance. Here, we identified novel Cryptococcus neoformans regulators of extracellular vesicle (EV) biogenesis that impact FLC resistance. In particular, the transcription factor Hap2 does not affect the expression of the drug target or efflux pumps, yet it impacts the cellular sterol profile. Subinhibitory FLC concentrations also downregulate EV production. Moreover, in vitro spontaneous FLC-resistant colonies showed altered EV production, and the acquisition of FLC resistance was associated with decreased EV production in clinical isolates. Finally, the reversion of FLC resistance was associated with increased EV production. These data suggest a model in which fungal cells can regulate EV production in place of regulating the drug target gene expression as a first line of defense against antifungal assault in this fungal pathogen. IMPORTANCE Extracellular vesicles (EVs) are membrane-enveloped particles that are released by cells into the extracellular space. Fungal EVs can mediate community interactions and biofilm formation, but their functions remain poorly understood. Here, we report the identification of the first regulators of EV production in the major fungal pathogen Cryptococcus neoformans. Surprisingly, we uncover a novel role of EVs in modulating antifungal drug resistance. Disruption of EV production was associated with altered lipid composition and changes in fluconazole susceptibility. Spontaneous azole-resistant mutants were deficient in EV production, while loss of resistance restored initial EV production levels. These findings were recapitulated in C. neoformans clinical isolates, indicating that azole resistance and EV production are coregulated in diverse strains. Our study reveals a new mechanism of drug resistance in which cells adapt to azole stress by modulating EV production.
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Affiliation(s)
- Juliana Rizzo
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adèle Trottier
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
| | - Frédérique Moyrand
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
| | - Jean-Yves Coppée
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
| | - Corinne Maufrais
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
- Institut Pasteur, Université Paris Cité, USR 3756 IP CNRS, HUB Bioinformatique et Biostatistique, Paris, France
| | - Ana Claudia G. Zimbres
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thi Tuong Vi Dang
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
| | - Alexandre Alanio
- Institut Pasteur, Université Paris Cité, Centre National de Référence Mycoses Invasives et Antifongiques, Groupe de recherche Mycologie Translationnelle, Département de Mycologie, Paris, France
- Laboratoire de parasitologie-mycologie, AP-HP, Hôpital Saint-Louis, Paris, France
| | - Marie Desnos-Ollivier
- Institut Pasteur, Université Paris Cité, Centre National de Référence Mycoses Invasives et Antifongiques, Groupe de recherche Mycologie Translationnelle, Département de Mycologie, Paris, France
| | - Isabelle Mouyna
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
| | - Gérard Péhau-Arnaude
- Institut Pasteur, Université Paris Cité, Plateforme de Bio-Imagerie Ultrastructurale, Paris, France
| | - Pierre-Henri Commere
- Institut Pasteur, Université Paris Cité, Cytometry and Biomarkers, Paris, France
| | - Sophie Novault
- Institut Pasteur, Université Paris Cité, Cytometry and Biomarkers, Paris, France
| | - Iuliana V. Ene
- Institut Pasteur, Université Paris Cité, Fungal Heterogeneity Group, Paris, France
| | - Leonardo Nimrichter
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcio L. Rodrigues
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (FIOCRUZ), Curitiba, Brazil
| | - Guilhem Janbon
- Institut Pasteur, Université Paris Cité, Unité Biologie des ARN des Pathogènes Fongiques, Paris, France
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9
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Knowles CM, Goich D, Bloom ALM, Kalem MC, Panepinto JC. Contributions of Ccr4 and Gcn2 to the Translational Response of C. neoformans to Host-Relevant Stressors and Integrated Stress Response Induction. mBio 2023; 14:e0019623. [PMID: 37017529 PMCID: PMC10127693 DOI: 10.1128/mbio.00196-23] [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: 01/27/2023] [Accepted: 03/06/2023] [Indexed: 04/06/2023] Open
Abstract
In response to the host environment, the human pathogen Cryptococcus neoformans must rapidly reprogram its translatome from one which promotes growth to one which is responsive to host stress. In this study, we investigate the two events which comprise translatome reprogramming: the removal of abundant, pro-growth mRNAs from the translating pool, and the regulated entry of stress-responsive mRNAs into the translating pool. Removal of pro-growth mRNAs from the translating pool is controlled primarily by two regulatory mechanisms, repression of translation initiation via Gcn2, and decay mediated by Ccr4. We determined that translatome reprogramming in response to oxidative stress requires both Gcn2 and Ccr4, whereas the response to temperature requires only Ccr4. Additionally, we assessed ribosome collision in response to host-relevant stress and found that collided ribosomes accumulated during temperature stress but not during oxidative stress. The phosphorylation of eIF2α that occurred as a result of translational stress led us to investigate the induction of the integrated stress response (ISR). We found that eIF2α phosphorylation varied in response to the type and magnitude of stress, yet all tested conditions induced translation of the ISR transcription factor Gcn4. However, Gcn4 translation did not necessarily result in canonical Gcn4-dependent transcription. Finally, we define the ISR regulon in response to oxidative stress. In conclusion, this study begins to reveal the translational regulation in response to host-relevant stressors in an environmental fungus which is capable of adapting to the environment inside the human host. IMPORTANCE Cryptococcus neoformans is a human pathogen capable of causing devastating infections. It must rapidly adapt to changing environments as it leaves its niche in the soil and enters the human lung. Previous work has demonstrated a need to reprogram gene expression at the level of translation to promote stress adaptation. In this work, we investigate the contributions and interplay of the major mechanisms that regulate entry of new mRNAs into the pool (translation initiation) and the clearance of unneeded mRNAs from the pool (mRNA decay). One result of this reprogramming is the induction of the integrated stress response (ISR) regulon. Surprisingly, all stresses tested led to the production of the ISR transcription factor Gcn4, but not necessarily to transcription of ISR target genes. Furthermore, stresses result in differential levels of ribosome collisions, but these are not necessarily predictive of initiation repression as has been suggested in the model yeast.
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Affiliation(s)
- Corey M. Knowles
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - David Goich
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Amanda L. M. Bloom
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Murat C. Kalem
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - John C. Panepinto
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
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10
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Guo R, Yu X, Gregory BD. The identification of conserved sequence features of co-translationally decayed mRNAs and upstream open reading frames in angiosperm transcriptomes. PLANT DIRECT 2023; 7:e479. [PMID: 36643787 PMCID: PMC9831718 DOI: 10.1002/pld3.479] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
RNA turnover is essential in maintaining messenger RNA (mRNA) homeostasis during various developmental stages and stress responses. Co-translational mRNA decay (CTRD), a process in which mRNAs are degraded while still associated with translating ribosomes, has recently been discovered to function in yeast and three angiosperm transcriptomes. However, it is still unclear how prevalent CTRD across the plant lineage. Moreover, the sequence features of co-translationally decayed mRNAs have not been well-studied. Here, utilizing a collection of publicly available degradome sequencing datasets for another seven angiosperm transcriptomes, we have confirmed that CTRD is functioning in at least 10 angiosperms and likely throughout the plant lineage. Additionally, we have identified sequence features shared by the co-translationally decayed mRNAs in these species, implying a possible conserved triggering mechanism for this pathway. Given that degradome sequencing datasets can also be used to identify actively translating upstream open reading frames (uORFs), which are quite understudied in plants, we have identified numerous actively translating uORFs in the same 10 angiosperms. These findings reveal that actively translating uORFs are prevalent in plant transcriptomes, some of which are conserved across this lineage. We have also observed conserved sequence features in the regions flanking these uORFs' stop codons that might contribute to ribosome stalling at these sequences. Finally, we discovered that there were very few overlaps between the mRNAs harboring actively translating uORFs and those sorted into the co-translational decay pathway in the majority of the studied angiosperms, suggesting that these two processes might be nearly mutually exclusive in those species. In total, our findings provide the identification of CTRD and actively translating uORFs across a broad collection of plants and provide novel insights into the important sequence features associated with these collections of mRNAs and regulatory elements, respectively.
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Affiliation(s)
- Rong Guo
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Xiang Yu
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Present address:
School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Brian D. Gregory
- Department of BiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
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11
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Dang TTV, Colin J, Janbon G. Alternative Transcription Start Site Usage and Functional Implications in Pathogenic Fungi. J Fungi (Basel) 2022; 8:1044. [PMID: 36294609 PMCID: PMC9604717 DOI: 10.3390/jof8101044] [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: 09/08/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/20/2022] Open
Abstract
Pathogenic fungi require delicate gene regulation mechanisms to adapt to diverse living environments and escape host immune systems. Recent advances in sequencing technology have exposed the complexity of the fungal genome, thus allowing the gradual disentanglement of multiple layers of gene expression control. Alternative transcription start site (aTSS) usage, previously reported to be prominent in mammals and to play important roles in physiopathology, is also present in fungi to fine-tune gene expression. Depending on the alteration in their sequences, RNA isoforms arising from aTSSs acquire different characteristics that significantly alter their stability and translational capacity as well as the properties and biologic functions of the resulting proteins. Disrupted control of aTSS usage has been reported to severely impair growth, virulence, and the infectious capacity of pathogenic fungi. Here, we discuss principle concepts, mechanisms, and the functional implication of aTSS usage in fungi.
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Affiliation(s)
- Thi Tuong Vi Dang
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, Université de Paris Cité, F-75015 Paris, France
| | - Jessie Colin
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, Université de Paris Cité, F-75015 Paris, France
- Ecole Pratique des Hautes Etudes, PSL Research University, F-75014 Paris, France
| | - Guilhem Janbon
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, Université de Paris Cité, F-75015 Paris, France
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12
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Bottorff TA, Park H, Geballe AP, Subramaniam AR. Translational buffering by ribosome stalling in upstream open reading frames. PLoS Genet 2022; 18:e1010460. [PMID: 36315596 PMCID: PMC9648851 DOI: 10.1371/journal.pgen.1010460] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/10/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022] Open
Abstract
Upstream open reading frames (uORFs) are present in over half of all human mRNAs. uORFs can potently regulate the translation of downstream open reading frames through several mechanisms: siphoning away scanning ribosomes, regulating re-initiation, and allowing interactions between scanning and elongating ribosomes. However, the consequences of these different mechanisms for the regulation of protein expression remain incompletely understood. Here, we performed systematic measurements on the uORF-containing 5' UTR of the cytomegaloviral UL4 mRNA to test alternative models of uORF-mediated regulation in human cells. We find that a terminal diproline-dependent elongating ribosome stall in the UL4 uORF prevents decreases in main ORF protein expression when ribosome loading onto the mRNA is reduced. This uORF-mediated buffering is insensitive to the location of the ribosome stall along the uORF. Computational kinetic modeling based on our measurements suggests that scanning ribosomes dissociate rather than queue when they collide with stalled elongating ribosomes within the UL4 uORF. We identify several human uORFs that repress main ORF protein expression via a similar terminal diproline motif. We propose that ribosome stalls in uORFs provide a general mechanism for buffering against reductions in main ORF translation during stress and developmental transitions.
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Affiliation(s)
- Ty A. Bottorff
- Basic Sciences Division and Computational Biology Program of the Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Biological Physics, Structure and Design Graduate Program, University of Washington, Seattle, Washington, United States of America
| | - Heungwon Park
- Basic Sciences Division and Computational Biology Program of the Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Adam P. Geballe
- Human Biology and Clinical Research Divisions, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Arvind Rasi Subramaniam
- Basic Sciences Division and Computational Biology Program of the Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Biological Physics, Structure and Design Graduate Program, University of Washington, Seattle, Washington, United States of America
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13
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Identification and characterisation of sPEPs in Cryptococcus neoformans. Fungal Genet Biol 2022; 160:103688. [PMID: 35339703 DOI: 10.1016/j.fgb.2022.103688] [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: 01/04/2022] [Revised: 03/02/2022] [Accepted: 03/21/2022] [Indexed: 11/24/2022]
Abstract
Short open reading frame (sORF)-encoded peptides (sPEPs) have been found across a wide range of genomic locations in a variety of species. To date, their identification, validation, and characterisation in the human fungal pathogen Cryptococcus neoformans has been limited due to a lack of standardised protocols. We have developed an enrichment process that enables sPEP detection within a protein sample from this polysaccharide-encapsulated yeast, and implemented proteogenomics to provide insights into the validity of predicted and hypothetical sORFs annotated in the C. neoformans genome. Novel sORFs were discovered within the 5' and 3' UTRs of known transcripts as well as in "non-coding" RNAs. One novel candidate, dubbed NPB1, that resided in an RNA annotated as "non-coding", was chosen for characterisation. Through the creation of both specific point mutations and a full deletion allele, the function of the new sPEP, Npb1, was shown to resemble that of the bacterial trans-translation protein SmpB.
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14
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Kalem MC, Panepinto JC. Long Non-Coding RNAs in Cryptococcus neoformans: Insights Into Fungal Pathogenesis. Front Cell Infect Microbiol 2022; 12:858317. [PMID: 35372111 PMCID: PMC8968117 DOI: 10.3389/fcimb.2022.858317] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/18/2022] [Indexed: 12/18/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) are highly expressed and can modulate multiple cellular processes including transcription, splicing, translation, and many diverse signaling events. LncRNAs can act as sponges for miRNAs, RNA and DNA binding proteins, functioning as competitive endogenous RNAs. The contribution of lncRNAs to microbial pathogenesis is largely neglected in eukaryotic pathogens despite the abundance of RNA sequencing datasets encompassing conditions of stress, gene deletions and conditions that mimic the host environment. The human fungal pathogen Cryptococcus neoformans encodes 6975 (84%) protein-coding and 1359 (16%) non-protein-coding RNAs, of which 1182 (14.2%) are lncRNAs defined by a threshold of greater than 200 nucleotides in length. Here, we discuss the current state of knowledge in C. neoformans lncRNA biology. Utilizing existing RNA seq datasets, we examine trends in lncRNA expression and discuss potential implications for pathogenesis.
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Affiliation(s)
- Murat C. Kalem
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, State University of New York (SUNY), University at Buffalo, Buffalo, NY, United States
| | - John C. Panepinto
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, State University of New York (SUNY), University at Buffalo, Buffalo, NY, United States
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15
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Telzrow CL, Zwack PJ, Esher Righi S, Dietrich FS, Chan C, Owzar K, Alspaugh JA, Granek JA. Comparative analysis of RNA enrichment methods for preparation of Cryptococcus neoformans RNA sequencing libraries. G3 (BETHESDA, MD.) 2021; 11:jkab301. [PMID: 34518880 PMCID: PMC8527493 DOI: 10.1093/g3journal/jkab301] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 08/19/2021] [Indexed: 11/13/2022]
Abstract
RNA sequencing (RNA-Seq) experiments focused on gene expression involve removal of ribosomal RNA (rRNA) because it is the major RNA constituent of cells. This process, called RNA enrichment, is done primarily to reduce cost: without rRNA removal, deeper sequencing must be performed to compensate for the sequencing reads wasted on rRNA. The ideal RNA enrichment method removes all rRNA without affecting other RNA in the sample. We tested the performance of three RNA enrichment methods on RNA isolated from Cryptococcus neoformans, a fungal pathogen of humans. We find that the RNase H depletion method is more efficient in depleting rRNA and more specific in recapitulating non-rRNA levels present in unenriched controls than the commonly-used Poly(A) isolation method. The RNase H depletion method is also more effective than the Ribo-Zero depletion method as measured by rRNA depletion efficiency and recapitulation of protein-coding RNA levels present in unenriched controls, while the Ribo-Zero depletion method more closely recapitulates annotated non-coding RNA (ncRNA) levels. Finally, we leverage these data to accurately map the C. neoformans mitochondrial rRNA genes, and also demonstrate that RNA-Seq data generated with the RNase H and Ribo-Zero depletion methods can be used to explore novel C. neoformans long non-coding RNA genes.
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Affiliation(s)
- Calla L Telzrow
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Paul J Zwack
- Department of Biology, Duke University, Durham, NC 27710, USA
| | - Shannon Esher Righi
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Fred S Dietrich
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Cliburn Chan
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - Kouros Owzar
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
- Duke Cancer Institute, Duke University, Durham, NC 27710, USA
| | - J Andrew Alspaugh
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Joshua A Granek
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
- Duke Cancer Institute, Duke University, Durham, NC 27710, USA
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16
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Rana A, Gupta N, Thakur A. Post-transcriptional and translational control of the morphology and virulence in human fungal pathogens. Mol Aspects Med 2021; 81:101017. [PMID: 34497025 DOI: 10.1016/j.mam.2021.101017] [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: 02/11/2021] [Revised: 08/13/2021] [Accepted: 08/20/2021] [Indexed: 11/17/2022]
Abstract
Host-pathogen interactions at the molecular level are the key to fungal pathogenesis. Fungal pathogens utilize several mechanisms such as adhesion, invasion, phenotype switching and metabolic adaptations, to survive in the host environment and respond. Post-transcriptional and translational regulations have emerged as key regulatory mechanisms ensuring the virulence and survival of fungal pathogens. Through these regulations, fungal pathogens effectively alter their protein pool, respond to various stress, and undergo morphogenesis, leading to efficient and comprehensive changes in fungal physiology. The regulation of virulence through post-transcriptional and translational regulatory mechanisms is mediated through mRNA elements (cis factors) or effector molecules (trans factors). The untranslated regions upstream and downstream of the mRNA, as well as various RNA-binding proteins involved in translation initiation or circularization of the mRNA, play pivotal roles in the regulation of morphology and virulence by influencing protein synthesis, protein isoforms, and mRNA stability. Therefore, post-transcriptional and translational mechanisms regulating the morphology, virulence and drug-resistance processes in fungal pathogens can be the target for new therapeutics. With improved "omics" technologies, these regulatory mechanisms are increasingly coming to the forefront of basic biology and drug discovery. This review aims to discuss various modes of post-transcriptional and translation regulations, and how these mechanisms exert influence in the virulence and morphogenesis of fungal pathogens.
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Affiliation(s)
- Aishwarya Rana
- Regional Centre for Biotechnology, 3rd Milestone Gurgaon-Faridabad Expressway, Faridabad 121001, India
| | - Nidhi Gupta
- Regional Centre for Biotechnology, 3rd Milestone Gurgaon-Faridabad Expressway, Faridabad 121001, India
| | - Anil Thakur
- Regional Centre for Biotechnology, 3rd Milestone Gurgaon-Faridabad Expressway, Faridabad 121001, India.
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17
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Rizzo J, Wong SSW, Gazi AD, Moyrand F, Chaze T, Commere P, Novault S, Matondo M, Péhau‐Arnaudet G, Reis FCG, Vos M, Alves LR, May RC, Nimrichter L, Rodrigues ML, Aimanianda V, Janbon G. Cryptococcus extracellular vesicles properties and their use as vaccine platforms. J Extracell Vesicles 2021; 10:e12129. [PMID: 34377375 PMCID: PMC8329992 DOI: 10.1002/jev2.12129] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 07/02/2021] [Accepted: 07/09/2021] [Indexed: 12/12/2022] Open
Abstract
Whereas extracellular vesicle (EV) research has become commonplace in different biomedical fields, this field of research is still in its infancy in mycology. Here we provide a robust set of data regarding the structural and compositional aspects of EVs isolated from the fungal pathogenic species Cryptococcus neoformans, C. deneoformans and C. deuterogattii. Using cutting-edge methodological approaches including cryogenic electron microscopy and cryogenic electron tomography, proteomics, and flow cytometry, we revisited cryptococcal EV features and suggest a new EV structural model, in which the vesicular lipid bilayer is covered by mannoprotein-based fibrillar decoration, bearing the capsule polysaccharide as its outer layer. About 10% of the EV population is devoid of fibrillar decoration, adding another aspect to EV diversity. By analysing EV protein cargo from the three species, we characterized the typical Cryptococcus EV proteome. It contains several membrane-bound protein families, including some Tsh proteins bearing a SUR7/PalI motif. The presence of known protective antigens on the surface of Cryptococcus EVs, resembling the morphology of encapsulated virus structures, suggested their potential as a vaccine. Indeed, mice immunized with EVs obtained from an acapsular C. neoformans mutant strain rendered a strong antibody response in mice and significantly prolonged their survival upon C. neoformans infection.
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Affiliation(s)
- Juliana Rizzo
- Unité Biologie des ARN des Pathogènes FongiquesDépartement de Mycologie, Institut Pasteur, F‐75015ParisFrance
| | - Sarah Sze Wah Wong
- Unité Mycologie Moléculaire, CNRS UMR2000Département de Mycologie, Institut Pasteur, F‐75015ParisFrance
| | - Anastasia D. Gazi
- Ultrastructural Bio‐Imaging, UTechS UBI, CNRS UMR 3528Département de Biologie cellulaire et infection, Institut Pasteur, F‐75015ParisFrance
| | - Frédérique Moyrand
- Unité Biologie des ARN des Pathogènes FongiquesDépartement de Mycologie, Institut Pasteur, F‐75015ParisFrance
| | - Thibault Chaze
- Plateforme Protéomique, Unité de Spectrométrie de Masse pour la Biologie (MSBio), CNRS UMR 2000Centre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, F‐75015ParisFrance
| | - Pierre‐Henri Commere
- Cytometry and BiomarkersCentre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, F‐75015ParisFrance
| | - Sophie Novault
- Cytometry and BiomarkersCentre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, F‐75015ParisFrance
| | - Mariette Matondo
- Plateforme Protéomique, Unité de Spectrométrie de Masse pour la Biologie (MSBio), CNRS UMR 2000Centre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, F‐75015ParisFrance
| | - Gérard Péhau‐Arnaudet
- Ultrastructural Bio‐Imaging, UTechS UBI, CNRS UMR 3528Département de Biologie cellulaire et infection, Institut Pasteur, F‐75015ParisFrance
| | - Flavia C. G. Reis
- Instituto Carlos ChagasFundação Oswaldo Cruz (FIOCRUZ)CuritibaBrazil
- Centro de Desenvolvimento Tecnologico em Saude (CDTS‐Fiocruz)São PauloBrazil
| | - Matthijn Vos
- NanoImaging Core FacilityCentre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, F‐75015ParisFrance
| | | | - Robin C. May
- Institute of Microbiology and Infection and School of BiosciencesUniversity of BirminghamBirminghamB15 2TTUK
| | - Leonardo Nimrichter
- Instituto de Microbiologia Paulo de Góes (IMPG)Universidade Federal do Rio de JaneiroRio de JaneiroBrazil
| | - Marcio L. Rodrigues
- Instituto Carlos ChagasFundação Oswaldo Cruz (FIOCRUZ)CuritibaBrazil
- Instituto de Microbiologia Paulo de Góes (IMPG)Universidade Federal do Rio de JaneiroRio de JaneiroBrazil
| | - Vishukumar Aimanianda
- Unité Mycologie Moléculaire, CNRS UMR2000Département de Mycologie, Institut Pasteur, F‐75015ParisFrance
| | - Guilhem Janbon
- Unité Biologie des ARN des Pathogènes FongiquesDépartement de Mycologie, Institut Pasteur, F‐75015ParisFrance
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18
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Xu L, Liu P, Dai Z, Fan F, Zhang X. Fine-tuning the expression of pathway gene in yeast using a regulatory library formed by fusing a synthetic minimal promoter with different Kozak variants. Microb Cell Fact 2021; 20:148. [PMID: 34320991 PMCID: PMC8317321 DOI: 10.1186/s12934-021-01641-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/21/2021] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Tailoring gene expression to balance metabolic fluxes is critical for the overproduction of metabolites in yeast hosts, and its implementation requires coordinated regulation at both transcriptional and translational levels. Although synthetic minimal yeast promoters have shown many advantages compared to natural promoters, their transcriptional strength is still limited, which restricts their applications in pathway engineering. RESULTS In this work, we sought to expand the application scope of synthetic minimal yeast promoters by enhancing the corresponding translation levels using specific Kozak sequence variants. Firstly, we chose the reported UASF-E-C-Core1 minimal promoter as a library template and determined its Kozak motif (K0). Next, we randomly mutated the K0 to generate a chimeric promoter library, which was able to drive green fluorescent protein (GFP) expression with translational strengths spanning a 500-fold range. A total of 14 chimeric promoters showed at least two-fold differences in GFP expression strength compared to the K0 control. The best one named K528 even showed 8.5- and 3.3-fold increases in fluorescence intensity compared with UASF-E-C-Core1 and the strong native constitutive promoter PTDH3, respectively. Subsequently, we chose three representative strong chimeric promoters (K540, K536, and K528) from this library to regulate pathway gene expression. In conjunction with the tHMG1 gene for squalene production, the K528 variant produced the best squalene titer of 32.1 mg/L in shake flasks, which represents a more than 10-fold increase compared to the parental K0 control (3.1 mg/L). CONCLUSIONS All these results demonstrate that this chimeric promoter library developed in this study is an effective tool for pathway engineering in yeast.
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Affiliation(s)
- Liping Xu
- School of Life Science, University of Science and Technology of China, No. 96, JinZhai Road, Baohe District, Hefei, Anhui, 230026, People's Republic of China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Pingping Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.,National Innovation Center for Synthetic Biotechnology, Tianjin, 300308, People's Republic of China
| | - Zhubo Dai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.,National Innovation Center for Synthetic Biotechnology, Tianjin, 300308, People's Republic of China
| | - Feiyu Fan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China. .,National Innovation Center for Synthetic Biotechnology, Tianjin, 300308, People's Republic of China.
| | - Xueli Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China. .,National Innovation Center for Synthetic Biotechnology, Tianjin, 300308, People's Republic of China.
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19
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Mundodi V, Choudhary S, Smith AD, Kadosh D. Global translational landscape of the Candida albicans morphological transition. G3-GENES GENOMES GENETICS 2021; 11:6046988. [PMID: 33585865 PMCID: PMC7849906 DOI: 10.1093/g3journal/jkaa043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/01/2020] [Indexed: 12/14/2022]
Abstract
Candida albicans, a major human fungal pathogen associated with high mortality and/or morbidity rates in a wide variety of immunocompromised individuals, undergoes a reversible morphological transition from yeast to filamentous cells that is required for virulence. While previous studies have identified and characterized global transcriptional mechanisms important for driving this transition, as well as other virulence properties, in C. albicans and other pathogens, considerably little is known about the role of genome-wide translational mechanisms. Using ribosome profiling, we report the first global translational profile associated with C. albicans morphogenesis. Strikingly, many genes involved in pathogenesis, filamentation, and the response to stress show reduced translational efficiency (TE). Several of these genes are known to be strongly induced at the transcriptional level, suggesting that a translational fine-tuning mechanism is in place. We also identify potential upstream open reading frames (uORFs), associated with genes involved in pathogenesis, and novel ORFs, several of which show altered TE during filamentation. Using a novel bioinformatics method for global analysis of ribosome pausing that will be applicable to a wide variety of genetic systems, we demonstrate an enrichment of ribosome pausing sites in C. albicans genes associated with protein synthesis and cell wall functions. Altogether, our results suggest that the C. albicans morphological transition, and most likely additional virulence processes in fungal pathogens, is associated with widespread global alterations in TE that do not simply reflect changes in transcript levels. These alterations affect the expression of many genes associated with processes essential for virulence and pathogenesis.
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Affiliation(s)
- Vasanthakrishna Mundodi
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Saket Choudhary
- Department of Computational Biology and Bioinformatics, University of Southern California, Los Angeles, CA 90089, USA
| | - Andrew D Smith
- Department of Computational Biology and Bioinformatics, University of Southern California, Los Angeles, CA 90089, USA
| | - David Kadosh
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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20
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Gröhs Ferrareze PA, Maufrais C, Silva Araujo Streit R, Priest SJ, Cuomo CA, Heitman J, Staats CC, Janbon G. Application of an optimized annotation pipeline to the Cryptococcus deuterogattii genome reveals dynamic primary metabolic gene clusters and genomic impact of RNAi loss. G3-GENES GENOMES GENETICS 2021; 11:6080769. [PMID: 33585873 PMCID: PMC8022950 DOI: 10.1093/g3journal/jkaa070] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/24/2020] [Indexed: 12/15/2022]
Abstract
Evaluating the quality of a de novo annotation of a complex fungal genome based on RNA-seq data remains a challenge. In this study, we sequentially optimized a Cufflinks-CodingQuary-based bioinformatics pipeline fed with RNA-seq data using the manually annotated model pathogenic yeasts Cryptococcus neoformans and Cryptococcus deneoformans as test cases. Our results show that the quality of the annotation is sensitive to the quantity of RNA-seq data used and that the best quality is obtained with 5–10 million reads per RNA-seq replicate. We also showed that the number of introns predicted is an excellent a priori indicator of the quality of the final de novo annotation. We then used this pipeline to annotate the genome of the RNAi-deficient species Cryptococcus deuterogattii strain R265 using RNA-seq data. Dynamic transcriptome analysis revealed that intron retention is more prominent in C. deuterogattii than in the other RNAi-proficient species C. neoformans and C. deneoformans. In contrast, we observed that antisense transcription was not higher in C. deuterogattii than in the two other Cryptococcus species. Comparative gene content analysis identified 21 clusters enriched in transcription factors and transporters that have been lost. Interestingly, analysis of the subtelomeric regions in these three annotated species identified a similar gene enrichment, reminiscent of the structure of primary metabolic clusters. Our data suggest that there is active exchange between subtelomeric regions, and that other chromosomal regions might participate in adaptive diversification of Cryptococcus metabolite assimilation potential.
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Affiliation(s)
- Patrícia Aline Gröhs Ferrareze
- Département de Mycologie, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, F-75015 Paris, France.,Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 15005, Brazil
| | - Corinne Maufrais
- Département de Mycologie, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, F-75015 Paris, France.,Département Biologie Computationnelle, Institut Pasteur, HUB Bioinformatique et Biostatistique, C3BI, USR 3756 IP CNRS, F-75015 Paris, France
| | - Rodrigo Silva Araujo Streit
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 15005, Brazil
| | - Shelby J Priest
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Christina A Cuomo
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Charley Christian Staats
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 15005, Brazil
| | - Guilhem Janbon
- Département de Mycologie, Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, F-75015 Paris, France
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21
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Stovall AK, Knowles CM, Kalem MC, Panepinto JC. A Conserved Gcn2-Gcn4 Axis Links Methionine Utilization and the Oxidative Stress Response in Cryptococcus neoformans. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:640678. [PMID: 34622246 PMCID: PMC8494424 DOI: 10.3389/ffunb.2021.640678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 03/01/2021] [Indexed: 11/13/2022]
Abstract
The fungal pathogen Cryptococcus neoformans relies on post-transcriptional mechanisms of gene regulation to adapt to stressors it encounters in the human host, such as oxidative stress and nutrient limitation. The kinase Gcn2 regulates translation in response to stress by phosphorylating the initiation factor eIF2, and it is a crucial factor in withstanding oxidative stress in C. neoformans, and amino acid limitation in many fungal species. However, little is known about the role of Gcn2 in nitrogen limitation in C. neoformans. In this study, we demonstrate that Gcn2 is required for C. neoformans to utilize methionine as a source of nitrogen, and that the presence of methionine as a sole nitrogen source induces eIF2 phosphorylation. The stress imposed by methionine leads to an oxidative stress response at both the levels of transcription and translation, as seen through polysome profiling as well as increased abundance of select oxidative stress response transcripts. The transcription factor Gcn4 is also required for methionine utilization and oxidative stress resistance, and RT-qPCR data suggests that it regulates expression of certain transcripts in response to oxidative stress. The results of this study suggest a connection between nitrogen metabolism and oxidative stress in C. neoformans that is mediated by Gcn4, possibly indicating the presence of a compound stress response in this clinically important fungal pathogen.
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Affiliation(s)
| | | | | | - John C. Panepinto
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York (SUNY), Buffalo, NY, United States
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22
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Knowles CM, McIntyre KM, Panepinto JC. Tools for Assessing Translation in Cryptococcus neoformans. J Fungi (Basel) 2021; 7:jof7030159. [PMID: 33668175 PMCID: PMC7995980 DOI: 10.3390/jof7030159] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/17/2021] [Accepted: 02/20/2021] [Indexed: 12/16/2022] Open
Abstract
Cryptococcus neoformans is a ubiquitous environmental fungus capable of establishing an infection in a human host. Rapid changes in environments and exposure to the host immune system results in a significant amount of cellular stress, which is effectively combated at the level of translatome reprogramming. Repression of translation following stress allows for the specific reallocation of limited resources. Understanding the mechanisms involved in regulating translation in C. neoformans during host infection is critical in the development of new antifungal drugs. In this review, we discuss the main tools available for assessing changes in translation state and translational output during cellular stress.
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23
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Smith AD, Garcia-Santamarina S, Ralle M, Loiselle DR, Haystead TA, Thiele DJ. Transcription factor-driven alternative localization of Cryptococcus neoformans superoxide dismutase. J Biol Chem 2021; 296:100391. [PMID: 33567338 PMCID: PMC7961099 DOI: 10.1016/j.jbc.2021.100391] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/29/2021] [Accepted: 02/04/2021] [Indexed: 12/16/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen whose pathogenic lifestyle is linked to its ability to cope with fluctuating levels of copper (Cu), an essential metal involved in multiple virulence mechanisms, within distinct host niches. During lethal cryptococcal meningitis in the brain, C. neoformans senses a Cu-deficient environment and is highly dependent on its ability to scavenge trace levels of Cu from its host and adapt to Cu scarcity to successfully colonize this niche. In this study, we demonstrate for this critical adaptation, the Cu-sensing transcription factor Cuf1 differentially regulates the expression of the SOD1 and SOD2 superoxide dismutases in novel ways. Genetic and transcriptional analysis reveals Cuf1 specifies 5’-truncations of the SOD1 and SOD2 mRNAs through specific binding to Cu responsive elements within their respective promoter regions. This results in Cuf1-dependent repression of the highly abundant SOD1 and simultaneously induces expression of two isoforms of SOD2, the canonical mitochondrial targeted isoform and a novel alternative cytosolic isoform, from a single alternative transcript produced specifically under Cu limitation. The generation of cytosolic Sod2 during Cu limitation is required to maintain cellular antioxidant defense against superoxide stress both in vitro and in vivo. Further, decoupling Cuf1 regulation of Sod2 localization compromises the ability of C. neoformans to colonize organs in murine models of cryptococcosis. Our results provide a link between transcription factor–mediated alteration of protein localization and cell proliferation under stress, which could impact tissue colonization by a fungal pathogen.
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Affiliation(s)
- Aaron D Smith
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| | | | - Martina Ralle
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon, USA
| | - David R Loiselle
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| | - Timothy A Haystead
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| | - Dennis J Thiele
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA; Department of Biochemistry, Duke University, Durham, North Carolina, USA; Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA.
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24
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Trainor BM, Ghosh A, Pestov DG, Hellen CUT, Shcherbik N. A translation enhancer element from black beetle virus engages yeast eIF4G1 to drive cap-independent translation initiation. Sci Rep 2021; 11:2461. [PMID: 33510277 PMCID: PMC7844027 DOI: 10.1038/s41598-021-82025-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/14/2021] [Indexed: 01/13/2023] Open
Abstract
Cap-independent translation initiation plays crucial roles in fine-tuning gene expression under global translation shutdown conditions. Translation of uncapped or de-capped transcripts can be stimulated by Cap-independent translation enhancer (CITE) elements, but the mechanisms of CITE-mediated translation initiation remain understudied. Here, we characterized a short 5ʹ-UTR RNA sequence from black beetle virus, BBV-seq. Mutational analysis indicates that the entire BBV-seq is required for efficient translation initiation, but this sequence does not operate as an IRES-type module. In yeast cell-free translation extracts, BBV-seq promoted efficient initiation on cap-free mRNA using a scanning mechanism. Moreover, BBV-seq can increase translation efficiency resulting from conventional cap-dependent translation initiation. Using genetic approaches, we found that BBV-seq exploits RNA-binding properties of eIF4G1 to promote initiation. Thus, BBV-seq constitutes a previously uncharacterized short, linear CITE that influences eIF4G1 to initiate 5′ end-dependent, cap-independent translation. These findings bring new insights into CITE-mediated translational control of gene expression.
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Affiliation(s)
- Brandon M Trainor
- Department of Cell Biology and Neuroscience, School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, NJ, 08084, USA.,Graduate School of Biomedical Sciences, Rowan University, 42 E. Laurel Road, Suite 2200, Stratford, NJ, 08084, USA
| | - Arnab Ghosh
- Department of Cell Biology and Neuroscience, School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, NJ, 08084, USA.,Center for Gene Regulation in Health and Disease, Cleveland State University, 2121 Euclid Ave, Cleveland, OH, 44115, USA
| | - Dimitri G Pestov
- Department of Cell Biology and Neuroscience, School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, NJ, 08084, USA
| | - Christopher U T Hellen
- Department of Cell Biology, State University of New York Downstate Health Sciences University, 450 Clarkson Avenue MSC 44, Brooklyn, NY, 11203, USA
| | - Natalia Shcherbik
- Department of Cell Biology and Neuroscience, School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, NJ, 08084, USA.
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25
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Akirtava C, McManus CJ. Control of translation by eukaryotic mRNA transcript leaders-Insights from high-throughput assays and computational modeling. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1623. [PMID: 32869519 DOI: 10.1002/wrna.1623] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/23/2020] [Accepted: 07/30/2020] [Indexed: 12/21/2022]
Abstract
Eukaryotic gene expression is tightly regulated during translation of mRNA to protein. Mis-regulation of translation can lead to aberrant proteins which accumulate in cancers and cause neurodegenerative diseases. Foundational studies on model genes established fundamental roles for mRNA 5' transcript leader (TL) sequences in controlling ribosome recruitment, scanning, and initiation. TL cis-regulatory elements and their corresponding trans-acting factors control cap-dependent initiation under unstressed conditions. Under stress, cap-dependent initiation is suppressed, and specific mRNA structures and sequences promote translation of stress-responsive transcripts to remodel the proteome. In this review, we summarize current knowledge of TL functions in translation initiation. We focus on insights from high-throughput analyses of ribosome occupancy, mRNA structure, RNA Binding Protein occupancy, and massively parallel reporter assays. These data-driven approaches, coupled with computational analyses and modeling, have paved the way for a comprehensive understanding of TL functions. Finally, we will discuss areas of future research on the roles of mRNA sequences and structures in translation. This article is categorized under: Translation > Translation Mechanisms RNA Evolution and Genomics > Computational Analyses of RNA RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems.
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Affiliation(s)
- Christina Akirtava
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Charles Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.,Computational Biology Department, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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26
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Blanco N, Williams AJ, Tang D, Zhan D, Misaghi S, Kelley RF, Simmons LC. Tailoring translational strength using Kozak sequence variants improves bispecific antibody assembly and reduces product‐related impurities in CHO cells. Biotechnol Bioeng 2020; 117:1946-1960. [DOI: 10.1002/bit.27347] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/06/2020] [Accepted: 03/29/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Noelia Blanco
- Departments of Cell CultureGenentech, Inc., 1 DNA Way South San Francisco California
| | - Ambrose J. Williams
- Departments of Purification DevelopmentGenentech, Inc., 1 DNA Way South San Francisco California
| | - Danming Tang
- Departments of Cell CultureGenentech, Inc., 1 DNA Way South San Francisco California
| | - Dejin Zhan
- Departments of Cell CultureGenentech, Inc., 1 DNA Way South San Francisco California
| | - Shahram Misaghi
- Departments of Cell CultureGenentech, Inc., 1 DNA Way South San Francisco California
| | - Robert F. Kelley
- Departments of Drug DeliveryGenentech, Inc., 1 DNA Way South San Francisco California
| | - Laura C. Simmons
- Departments of Cell CultureGenentech, Inc., 1 DNA Way South San Francisco California
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