1
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Zheng D, Wang J, Persyn L, Liu Y, Montoya FU, Cenik C, Agarwal V. Predicting the translation efficiency of messenger RNA in mammalian cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.11.607362. [PMID: 39149337 PMCID: PMC11326250 DOI: 10.1101/2024.08.11.607362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
The degree to which translational control is specified by mRNA sequence is poorly understood in mammalian cells. Here, we constructed and leveraged a compendium of 3,819 ribosomal profiling datasets, distilling them into a transcriptome-wide atlas of translation efficiency (TE) measurements encompassing >140 human and mouse cell types. We subsequently developed RiboNN, a multitask deep convolutional neural network, and classic machine learning models to predict TEs in hundreds of cell types from sequence-encoded mRNA features, achieving state-of-the-art performance (r=0.79 in human and r=0.78 in mouse for mean TE across cell types). While the majority of earlier models solely considered 5' UTR sequence, RiboNN integrates contributions from the full-length mRNA sequence, learning that the 5' UTR, CDS, and 3' UTR respectively possess ~67%, 31%, and 2% per-nucleotide information density in the specification of mammalian TEs. Interpretation of RiboNN revealed that the spatial positioning of low-level di- and tri-nucleotide features (i.e., including codons) largely explain model performance, capturing mechanistic principles such as how ribosomal processivity and tRNA abundance control translational output. RiboNN is predictive of the translational behavior of base-modified therapeutic RNA, and can explain evolutionary selection pressures in human 5' UTRs. Finally, it detects a common language governing mRNA regulatory control and highlights the interconnectedness of mRNA translation, stability, and localization in mammalian organisms.
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Affiliation(s)
- Dinghai Zheng
- mRNA Center of Excellence, Sanofi, Waltham, MA 02451, USA
| | - Jun Wang
- mRNA Center of Excellence, Sanofi, Waltham, MA 02451, USA
| | - Logan Persyn
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Yue Liu
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | | | - Can Cenik
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Vikram Agarwal
- mRNA Center of Excellence, Sanofi, Waltham, MA 02451, USA
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2
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Wang J, Gao G, Wang D. Developing AAV-delivered nonsense suppressor tRNAs for neurological disorders. Neurotherapeutics 2024; 21:e00391. [PMID: 38959711 PMCID: PMC11269797 DOI: 10.1016/j.neurot.2024.e00391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 05/29/2024] [Accepted: 06/19/2024] [Indexed: 07/05/2024] Open
Abstract
Adeno-associated virus (AAV)-based gene therapy is a clinical stage therapeutic modality for neurological disorders. A common genetic defect in myriad monogenic neurological disorders is nonsense mutations that account for about 11% of all human pathogenic mutations. Stop codon readthrough by suppressor transfer RNA (sup-tRNA) has long been sought as a potential gene therapy approach to target nonsense mutations, but hindered by inefficient in vivo delivery. The rapid advances in AAV delivery technology have not only powered gene therapy development but also enabled in vivo preclinical assessment of a range of nucleic acid therapeutics, such as sup-tRNA. Compared with conventional AAV gene therapy that delivers a transgene to produce therapeutic proteins, AAV-delivered sup-tRNA has several advantages, such as small gene sizes and operating within the endogenous gene expression regulation, which are important considerations for treating some neurological disorders. This review will first examine sup-tRNA designs and delivery by AAV vectors. We will then analyze how AAV-delivered sup-tRNA can potentially address some neurological disorders that are challenging to conventional gene therapy, followed by discussing available mouse models of neurological diseases for in vivo preclinical testing. Potential challenges for AAV-delivered sup-tRNA to achieve therapeutic efficacy and safety will also be discussed.
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Affiliation(s)
- Jiaming Wang
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
| | - Dan Wang
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
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3
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Ward C, Beharry A, Tennakoon R, Rozik P, Wilhelm SDP, Heinemann IU, O’Donoghue P. Mechanisms and Delivery of tRNA Therapeutics. Chem Rev 2024; 124:7976-8008. [PMID: 38801719 PMCID: PMC11212642 DOI: 10.1021/acs.chemrev.4c00142] [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: 02/19/2024] [Revised: 04/11/2024] [Accepted: 04/26/2024] [Indexed: 05/29/2024]
Abstract
Transfer ribonucleic acid (tRNA) therapeutics will provide personalized and mutation specific medicines to treat human genetic diseases for which no cures currently exist. The tRNAs are a family of adaptor molecules that interpret the nucleic acid sequences in our genes into the amino acid sequences of proteins that dictate cell function. Humans encode more than 600 tRNA genes. Interestingly, even healthy individuals contain some mutant tRNAs that make mistakes. Missense suppressor tRNAs insert the wrong amino acid in proteins, and nonsense suppressor tRNAs read through premature stop signals to generate full length proteins. Mutations that underlie many human diseases, including neurodegenerative diseases, cancers, and diverse rare genetic disorders, result from missense or nonsense mutations. Thus, specific tRNA variants can be strategically deployed as therapeutic agents to correct genetic defects. We review the mechanisms of tRNA therapeutic activity, the nature of the therapeutic window for nonsense and missense suppression as well as wild-type tRNA supplementation. We discuss the challenges and promises of delivering tRNAs as synthetic RNAs or as gene therapies. Together, tRNA medicines will provide novel treatments for common and rare genetic diseases in humans.
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Affiliation(s)
- Cian Ward
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Aruun Beharry
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Rasangi Tennakoon
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Peter Rozik
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Sarah D. P. Wilhelm
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Ilka U. Heinemann
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Patrick O’Donoghue
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
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4
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Doura T, Matsuoka Y, Kiyonaka S. Hijacking endogenous mRNA for genetic code expansion. Nat Chem Biol 2024; 20:660-661. [PMID: 38454074 DOI: 10.1038/s41589-024-01574-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Affiliation(s)
- Tomohiro Doura
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
| | - Yuma Matsuoka
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
| | - Shigeki Kiyonaka
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan.
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Nagoya, Japan.
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5
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Hikmat H, Le Targa L, Boschi C, Py J, Bedotto M, Morand A, Cassir N, Aherfi S, La Scola B, Colson P. Sequencing and characterization of human bocavirus genomes from patients diagnosed in Southern France between 2017 and 2022. J Med Virol 2024; 96:e29706. [PMID: 38888111 DOI: 10.1002/jmv.29706] [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: 02/07/2024] [Revised: 05/03/2024] [Accepted: 05/13/2024] [Indexed: 06/20/2024]
Abstract
The diversity and evolution of the genomes of human bocavirus (HBoV), which causes respiratory diseases, have been scarcely studied. Here, we aimed to obtain and characterize HBoV genomes from patients's nasopharyngeal samples collected between 2017 and 2022 period (5 years and 7 months). Next-generation sequencing (NGS) used Illumina technology after having implemented using GEMI an in-house multiplex PCR amplification strategy. Genomes were assembled and analyzed with CLC Genomics, Mafft, BioEdit, MeV, Nextclade, MEGA, and iTol. A total of 213 genomes were obtained. Phylogeny classified them all as of Bocavirus 1 (HBoV1) species. Five HBoV1 genotypic clusters determined by hierarchical clustering analysis of 27 variable genome positions were scattered over the study period although with differences in yearly prevalence. A total of 167 amino acid substitutions were detected. Besides, coinfection was observed for 52% of the samples, rhinoviruses then adenoviruses (HAdVs) being the most common viruses. Principal component analysis showed that HBoV1 genotypic cluster α tended to be correlated with HAdV co-infection. Subsequent HAdV typing for HBoV1-positive samples and negative controls demonstrated that HAdVC species predominated but HAdVB was that significantly HBoV1-associated. Overall, we described here the first HBoV1 genomes sequenced for France. HBoV1 and HAdVB association deserves further investigation.
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Affiliation(s)
- Houmadi Hikmat
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
| | - Lorlane Le Targa
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Biosellal, Lyon, France
| | - Celine Boschi
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
| | - Justine Py
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
| | - Marielle Bedotto
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
| | - Aurélie Morand
- Service d'Accueil des Urgences Pédiatriques, Hôpital Nord, AP-HM, Marseille, France
- Service de Pédiatrie Générale, Hôpital Timone, AP-HM, Marseille, France
| | - Nadim Cassir
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
| | - Sarah Aherfi
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
| | - Bernard La Scola
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
| | - Philippe Colson
- Microbes Evolution Phylogeny and Infection (MEPHI), Aix-Marseille Universite, Marseille, France
- IHU Méditerranée Infection, Marseille, France
- Assistance Publique-Hôpitaux de Marseille (AP-HM), Marseille, France
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6
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Kozma E, Kele P. Bioorthogonal Reactions in Bioimaging. Top Curr Chem (Cham) 2024; 382:7. [PMID: 38400853 PMCID: PMC10894152 DOI: 10.1007/s41061-024-00452-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/22/2024] [Indexed: 02/26/2024]
Abstract
Visualization of biomolecules in their native environment or imaging-aided understanding of more complex biomolecular processes are one of the focus areas of chemical biology research, which requires selective, often site-specific labeling of targets. This challenging task is effectively addressed by bioorthogonal chemistry tools in combination with advanced synthetic biology methods. Today, the smart combination of the elements of the bioorthogonal toolbox allows selective installation of multiple markers to selected targets, enabling multicolor or multimodal imaging of biomolecules. Furthermore, recent developments in bioorthogonally applicable probe design that meet the growing demands of superresolution microscopy enable more complex questions to be addressed. These novel, advanced probes enable highly sensitive, low-background, single- or multiphoton imaging of biological species and events in live organisms at resolutions comparable to the size of the biomolecule of interest. Herein, the latest developments in bioorthogonal fluorescent probe design and labeling schemes will be discussed in the context of in cellulo/in vivo (multicolor and/or superresolved) imaging schemes. The second part focuses on the importance of genetically engineered minimal bioorthogonal tags, with a particular interest in site-specific protein tagging applications to answer biological questions.
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Affiliation(s)
- Eszter Kozma
- Chemical Biology Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, Magyar Tudósok Krt. 2, Budapest, 1117, Hungary
| | - Péter Kele
- Chemical Biology Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, Magyar Tudósok Krt. 2, Budapest, 1117, Hungary.
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7
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Müller MBD, Kasturi P, Jayaraj GG, Hartl FU. Mechanisms of readthrough mitigation reveal principles of GCN1-mediated translational quality control. Cell 2023:S0092-8674(23)00587-1. [PMID: 37339632 PMCID: PMC10364623 DOI: 10.1016/j.cell.2023.05.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 05/17/2023] [Accepted: 05/24/2023] [Indexed: 06/22/2023]
Abstract
Readthrough into the 3' untranslated region (3' UTR) of the mRNA results in the production of aberrant proteins. Metazoans efficiently clear readthrough proteins, but the underlying mechanisms remain unknown. Here, we show in Caenorhabditis elegans and mammalian cells that readthrough proteins are targeted by a coupled, two-level quality control pathway involving the BAG6 chaperone complex and the ribosome-collision-sensing protein GCN1. Readthrough proteins with hydrophobic C-terminal extensions (CTEs) are recognized by SGTA-BAG6 and ubiquitylated by RNF126 for proteasomal degradation. Additionally, cotranslational mRNA decay initiated by GCN1 and CCR4/NOT limits the accumulation of readthrough products. Unexpectedly, selective ribosome profiling uncovered a general role of GCN1 in regulating translation dynamics when ribosomes collide at nonoptimal codons, enriched in 3' UTRs, transmembrane proteins, and collagens. GCN1 dysfunction increasingly perturbs these protein classes during aging, resulting in mRNA and proteome imbalance. Our results define GCN1 as a key factor acting during translation in maintaining protein homeostasis.
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Affiliation(s)
- Martin B D Müller
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Prasad Kasturi
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Gopal G Jayaraj
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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8
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Kesner JS, Chen Z, Shi P, Aparicio AO, Murphy MR, Guo Y, Trehan A, Lipponen JE, Recinos Y, Myeku N, Wu X. Noncoding translation mitigation. Nature 2023; 617:395-402. [PMID: 37046090 PMCID: PMC10560126 DOI: 10.1038/s41586-023-05946-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 03/13/2023] [Indexed: 04/14/2023]
Abstract
Translation is pervasive outside of canonical coding regions, occurring in long noncoding RNAs, canonical untranslated regions and introns1-4, especially in ageing4-6, neurodegeneration5,7 and cancer8-10. Notably, the majority of tumour-specific antigens are results of noncoding translation11-13. Although the resulting polypeptides are often nonfunctional, translation of noncoding regions is nonetheless necessary for the birth of new coding sequences14,15. The mechanisms underlying the surveillance of translation in diverse noncoding regions and how escaped polypeptides evolve new functions remain unclear10,16-19. Functional polypeptides derived from annotated noncoding sequences often localize to membranes20,21. Here we integrate massively parallel analyses of more than 10,000 human genomic sequences and millions of random sequences with genome-wide CRISPR screens, accompanied by in-depth genetic and biochemical characterizations. Our results show that the intrinsic nucleotide bias in the noncoding genome and in the genetic code frequently results in polypeptides with a hydrophobic C-terminal tail, which is captured by the ribosome-associated BAG6 membrane protein triage complex for either proteasomal degradation or membrane targeting. By contrast, canonical proteins have evolved to deplete C-terminal hydrophobic residues. Our results reveal a fail-safe mechanism for the surveillance of unwanted translation from diverse noncoding regions and suggest a possible biochemical route for the preferential membrane localization of newly evolved proteins.
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Affiliation(s)
- Jordan S Kesner
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Ziheng Chen
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Peiguo Shi
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Alexis O Aparicio
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Michael R Murphy
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Yang Guo
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Aditi Trehan
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Jessica E Lipponen
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Yocelyn Recinos
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Natura Myeku
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Xuebing Wu
- Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA.
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY, USA.
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9
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Wagner RN, Wießner M, Friedrich A, Zandanell J, Breitenbach-Koller H, Bauer JW. Emerging Personalized Opportunities for Enhancing Translational Readthrough in Rare Genetic Diseases and Beyond. Int J Mol Sci 2023; 24:6101. [PMID: 37047074 PMCID: PMC10093890 DOI: 10.3390/ijms24076101] [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: 02/16/2023] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 04/14/2023] Open
Abstract
Nonsense mutations trigger premature translation termination and often give rise to prevalent and rare genetic diseases. Consequently, the pharmacological suppression of an unscheduled stop codon represents an attractive treatment option and is of high clinical relevance. At the molecular level, the ability of the ribosome to continue translation past a stop codon is designated stop codon readthrough (SCR). SCR of disease-causing premature termination codons (PTCs) is minimal but small molecule interventions, such as treatment with aminoglycoside antibiotics, can enhance its frequency. In this review, we summarize the current understanding of translation termination (both at PTCs and at cognate stop codons) and highlight recently discovered pathways that influence its fidelity. We describe the mechanisms involved in the recognition and readthrough of PTCs and report on SCR-inducing compounds currently explored in preclinical research and clinical trials. We conclude by reviewing the ongoing attempts of personalized nonsense suppression therapy in different disease contexts, including the genetic skin condition epidermolysis bullosa.
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Affiliation(s)
- Roland N. Wagner
- Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria
| | - Michael Wießner
- Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria
| | - Andreas Friedrich
- Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria
| | - Johanna Zandanell
- Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria
| | | | - Johann W. Bauer
- Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria
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10
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Manjunath LE, Singh A, Som S, Eswarappa SM. Mammalian proteome expansion by stop codon readthrough. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1739. [PMID: 35570338 DOI: 10.1002/wrna.1739] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 04/11/2022] [Accepted: 04/16/2022] [Indexed: 12/20/2022]
Abstract
Recognition of a stop codon by translation machinery as a sense codon results in translational readthrough instead of termination. This recoding process, termed stop codon readthrough (SCR) or translational readthrough, is found in all domains of life including mammals. The context of the stop codon, local mRNA topology, and molecules that interact with the mRNA region downstream of the stop codon determine SCR. The products of SCR can have localization, stability, and function different from those of the canonical isoforms. In this review, we discuss how recent technological and computational advances have increased our understanding of the SCR process in the mammalian system. Based on the known molecular events that occur during SCR of multiple mRNAs, we propose transient molecular roadblocks on an mRNA downstream of the stop codon as a possible mechanism for the induction of SCR. We argue, with examples, that the insights gained from the natural SCR events can guide us to develop novel strategies for the treatment of diseases caused by premature stop codons. This article is categorized under: Translation > Regulation.
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Affiliation(s)
- Lekha E Manjunath
- Department of Biochemistry, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Anumeha Singh
- Department of Biochemistry, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Saubhik Som
- Department of Biochemistry, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Sandeep M Eswarappa
- Department of Biochemistry, Indian Institute of Science, Bengaluru, Karnataka, India
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11
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Lightfoot HL, Smith GF. Targeting RNA with small molecules-A safety perspective. Br J Pharmacol 2023. [PMID: 36631428 DOI: 10.1111/bph.16027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 06/30/2022] [Accepted: 12/20/2022] [Indexed: 01/13/2023] Open
Abstract
RNA is a major player in cellular function, and consequently can drive a number of disease pathologies. Over the past several years, small molecule-RNA targeting (smRNA targeting) has developed into a promising drug discovery approach. Numerous techniques, tools, and assays have been developed to support this field, and significant investments have been made by pharmaceutical and biotechnology companies. To date, the focus has been on identifying disease validated primary targets for smRNA drug development, yet RNA as a secondary (off) target for all small molecule drug programs largely has been unexplored. In this perspective, we discuss structure, target, and mechanism-driven safety aspects of smRNAs and highlight how these parameters can be evaluated in drug discovery programs to produce potentially safer drugs.
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Affiliation(s)
- Helen L Lightfoot
- Safety and Mechanistic Pharmacology, Clinical Pharmacology and Safety Sciences, R&D, AstraZeneca, Cambridge, UK
| | - Graham F Smith
- Data Science and AI, Clinical Pharmacology and Safety Sciences, R&D, AstraZeneca, Cambridge, UK
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12
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Autophagy in Hematological Malignancies. Cancers (Basel) 2022; 14:cancers14205072. [PMID: 36291856 PMCID: PMC9600546 DOI: 10.3390/cancers14205072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 10/10/2022] [Accepted: 10/13/2022] [Indexed: 11/29/2022] Open
Abstract
Simple Summary Autophagy is a dynamic and tightly regulated process that seems to have dual effects in cancer. In some contexts, it can induce carcinogenesis and promote cancer cell survival, whereas in others, it acts preventing tumor cell growth and tumor progression. Thus, autophagy functions seem to strictly depend on cancer ontogenesis, progression, and type. Here, we will dive into the current knowledge of autophagy in hematological malignancies and will highlight the main genetic components involved in each cancer type. Abstract Autophagy is a highly conserved metabolic pathway via which unwanted intracellular materials, such as unfolded proteins or damaged organelles, are digested. It is activated in response to conditions of oxidative stress or starvation, and is essential for the maintenance of cellular homeostasis and other vital functions, such as differentiation, cell death, and the cell cycle. Therefore, autophagy plays an important role in the initiation and progression of tumors, including hematological malignancies, where damaged autophagy during hematopoiesis can cause malignant transformation and increase cell proliferation. Over the last decade, the importance of autophagy in response to standard pharmacological treatment of hematological tumors has been observed, revealing completely opposite roles depending on the tumor type and stage. Thus, autophagy can promote tumor survival by attenuating the cellular damage caused by drugs and/or stabilizing oncogenic proteins, but can also have an antitumoral effect due to autophagic cell death. Therefore, autophagy-based strategies must depend on the context to create specific and safe combination therapies that could contribute to improved clinical outcomes. In this review, we describe the process of autophagy and its role on hematopoiesis, and we highlight recent research investigating its role as a potential therapeutic target in hematological malignancies. The findings suggest that genetic variants within autophagy-related genes modulate the risk of developing hemopathies, as well as patient survival.
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13
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AAV-delivered suppressor tRNA overcomes a nonsense mutation in mice. Nature 2022; 604:343-348. [PMID: 35322228 PMCID: PMC9446716 DOI: 10.1038/s41586-022-04533-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/05/2022] [Indexed: 12/19/2022]
Abstract
Gene therapy is a potentially curative medicine for many currently untreatable diseases, and recombinant adeno-associated virus (rAAV) is the most successful gene delivery vehicle for in vivo applications1-3. However, rAAV-based gene therapy suffers from several limitations, such as constrained DNA cargo size and toxicities caused by non-physiological expression of a transgene4-6. Here we show that rAAV delivery of a suppressor tRNA (rAAV.sup-tRNA) safely and efficiently rescued a genetic disease in a mouse model carrying a nonsense mutation, and effects lasted for more than 6 months after a single treatment. Mechanistically, this was achieved through a synergistic effect of premature stop codon readthrough and inhibition of nonsense-mediated mRNA decay. rAAV.sup-tRNA had a limited effect on global readthrough at normal stop codons and did not perturb endogenous tRNA homeostasis, as determined by ribosome profiling and tRNA sequencing, respectively. By optimizing the AAV capsid and the route of administration, therapeutic efficacy in various target tissues was achieved, including liver, heart, skeletal muscle and brain. This study demonstrates the feasibility of developing a toolbox of AAV-delivered nonsense suppressor tRNAs operating on premature termination codons (AAV-NoSTOP) to rescue pathogenic nonsense mutations and restore gene function under endogenous regulation. As nonsense mutations account for 11% of pathogenic mutations, AAV-NoSTOP can benefit a large number of patients. AAV-NoSTOP obviates the need to deliver a full-length protein-coding gene that may exceed the rAAV packaging limit, elicit adverse immune responses or cause transgene-related toxicities. It therefore represents a valuable addition to gene therapeutics.
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14
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Arsić A, Hagemann C, Stajković N, Schubert T, Nikić-Spiegel I. Minimal genetically encoded tags for fluorescent protein labeling in living neurons. Nat Commun 2022; 13:314. [PMID: 35031604 PMCID: PMC8760255 DOI: 10.1038/s41467-022-27956-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 12/22/2021] [Indexed: 12/25/2022] Open
Abstract
Modern light microscopy, including super-resolution techniques, has brought about a demand for small labeling tags that bring the fluorophore closer to the target. This challenge can be addressed by labeling unnatural amino acids (UAAs) with bioorthogonal click chemistry. The minimal size of the UAA and the possibility to couple the fluorophores directly to the protein of interest with single-residue precision in living cells make click labeling unique. Here, we establish click labeling in living primary neurons and use it for fixed-cell, live-cell, dual-color pulse-chase, and super-resolution microscopy of neurofilament light chain (NFL). We also show that click labeling can be combined with CRISPR/Cas9 genome engineering for tagging endogenous NFL. Due to its versatile nature and compatibility with advanced multicolor microscopy techniques, we anticipate that click labeling will contribute to novel discoveries in the neurobiology field.
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Affiliation(s)
- Aleksandra Arsić
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Cathleen Hagemann
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Nevena Stajković
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Timm Schubert
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany
| | - Ivana Nikić-Spiegel
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany.
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15
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Aphicho K, Kittipanukul N, Uttamapinant C. Visualizing the complexity of proteins in living cells with genetic code expansion. Curr Opin Chem Biol 2022; 66:102108. [PMID: 35026612 DOI: 10.1016/j.cbpa.2021.102108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/30/2021] [Accepted: 12/07/2021] [Indexed: 12/28/2022]
Abstract
Genetic code expansion has emerged as an enabling tool to provide insight into functions of understudied proteinogenic species, such as small proteins and peptides, and to probe protein biophysics in the cellular context. Here, we discuss recent technical advances and applications of genetic code expansion in cellular imaging of complex mammalian protein species, along with considerations and challenges on using the method.
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Affiliation(s)
- Kanokpol Aphicho
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand
| | - Narongyot Kittipanukul
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand
| | - Chayasith Uttamapinant
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand.
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16
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Bartoschek MD, Ugur E, Nguyen TA, Rodschinka G, Wierer M, Lang K, Bultmann S. Identification of permissive amber suppression sites for efficient non-canonical amino acid incorporation in mammalian cells. Nucleic Acids Res 2021; 49:e62. [PMID: 33684219 PMCID: PMC8216290 DOI: 10.1093/nar/gkab132] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 12/20/2022] Open
Abstract
The genetic code of mammalian cells can be expanded to allow the incorporation of non-canonical amino acids (ncAAs) by suppressing in-frame amber stop codons (UAG) with an orthogonal pyrrolysyl-tRNA synthetase (PylRS)/tRNAPylCUA (PylT) pair. However, the feasibility of this approach is substantially hampered by unpredictable variations in incorporation efficiencies at different stop codon positions within target proteins. Here, we apply a proteomics-based approach to quantify ncAA incorporation rates at hundreds of endogenous amber stop codons in mammalian cells. With these data, we compute iPASS (Identification of Permissive Amber Sites for Suppression; available at www.bultmannlab.eu/tools/iPASS), a linear regression model to predict relative ncAA incorporation efficiencies depending on the surrounding sequence context. To verify iPASS, we develop a dual-fluorescence reporter for high-throughput flow-cytometry analysis that reproducibly yields context-specific ncAA incorporation efficiencies. We show that nucleotides up- and downstream of UAG synergistically influence ncAA incorporation efficiency independent of cell line and ncAA identity. Additionally, we demonstrate iPASS-guided optimization of ncAA incorporation rates by synonymous exchange of codons flanking the amber stop codon. This combination of in silico analysis followed by validation in living mammalian cells substantially simplifies identification as well as adaptation of sites within a target protein to confer high ncAA incorporation rates.
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Affiliation(s)
- Michael D Bartoschek
- Department of Biology II and Center for Molecular Biosystems (BioSysM), Human Biology and BioImaging, Ludwig-Maximilians-Universität München, Munich 81377, Germany
| | - Enes Ugur
- Department of Biology II and Center for Molecular Biosystems (BioSysM), Human Biology and BioImaging, Ludwig-Maximilians-Universität München, Munich 81377, Germany.,Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Tuan-Anh Nguyen
- Department of Chemistry, Synthetic Biochemistry, Technical University of Munich, Garching 85748, Germany
| | - Geraldine Rodschinka
- Department of Biology II and Center for Molecular Biosystems (BioSysM), Human Biology and BioImaging, Ludwig-Maximilians-Universität München, Munich 81377, Germany
| | - Michael Wierer
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Kathrin Lang
- Department of Chemistry, Synthetic Biochemistry, Technical University of Munich, Garching 85748, Germany
| | - Sebastian Bultmann
- Department of Biology II and Center for Molecular Biosystems (BioSysM), Human Biology and BioImaging, Ludwig-Maximilians-Universität München, Munich 81377, Germany
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17
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Porter JJ, Heil CS, Lueck JD. Therapeutic promise of engineered nonsense suppressor tRNAs. WILEY INTERDISCIPLINARY REVIEWS. RNA 2021; 12:e1641. [PMID: 33567469 PMCID: PMC8244042 DOI: 10.1002/wrna.1641] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 12/11/2022]
Abstract
Nonsense mutations change an amino acid codon to a premature termination codon (PTC) generally through a single-nucleotide substitution. The generation of a PTC results in a defective truncated protein and often in severe forms of disease. Because of the exceedingly high prevalence of nonsense-associated diseases and a unifying mechanism, there has been a concerted effort to identify PTC therapeutics. Most clinical trials for PTC therapeutics have been conducted with small molecules that promote PTC read through and incorporation of a near-cognate amino acid. However, there is a need for PTC suppression agents that recode PTCs with the correct amino acid while being applicable to PTC mutations in many different genomic landscapes. With these characteristics, a single therapeutic will be able to treat several disease-causing PTCs. In this review, we will focus on the use of nonsense suppression technologies, in particular, suppressor tRNAs (sup-tRNAs), as possible therapeutics for correcting PTCs. Sup-tRNAs have many attractive qualities as possible therapeutic agents although there are knowledge gaps on their function in mammalian cells and technical hurdles that need to be overcome before their promise is realized. This article is categorized under: RNA Processing > tRNA Processing Translation > Translation Regulation.
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Affiliation(s)
- Joseph J. Porter
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
| | - Christina S. Heil
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
| | - John D. Lueck
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
- Department of NeurologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
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18
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Baradaran-Heravi A, Balgi AD, Hosseini-Farahabadi S, Choi K, Has C, Roberge M. Effect of small molecule eRF3 degraders on premature termination codon readthrough. Nucleic Acids Res 2021; 49:3692-3708. [PMID: 33764477 PMCID: PMC8053119 DOI: 10.1093/nar/gkab194] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 12/16/2022] Open
Abstract
Premature termination codon (PTC) readthrough is considered a potential treatment for genetic diseases caused by nonsense mutations. High concentrations of aminoglycosides induce low levels of PTC readthrough but also elicit severe toxicity. Identifying compounds that enhance PTC readthrough by aminoglycosides or reduce their toxicity is a continuing challenge. In humans, a binary complex of eukaryotic release factors 1 (eRF1) and 3 (eRF3a or eRF3b) mediates translation termination. They also participate in the SURF (SMG1-UPF1-eRF1-eRF3) complex assembly involved in nonsense-mediated mRNA decay (NMD). We show that PTC readthrough by aminoglycoside G418 is considerably enhanced by eRF3a and eRF3b siRNAs and cereblon E3 ligase modulators CC-885 and CC-90009, which induce proteasomal degradation of eRF3a and eRF3b. eRF3 degradation also reduces eRF1 levels and upregulates UPF1 and selectively stabilizes TP53 transcripts bearing a nonsense mutation over WT, indicating NMD suppression. CC-90009 is considerably less toxic than CC-885 and it enhances PTC readthrough in combination with aminoglycosides in mucopolysaccharidosis type I-Hurler, late infantile neuronal ceroid lipofuscinosis, Duchenne muscular dystrophy and junctional epidermolysis bullosa patient-derived cells with nonsense mutations in the IDUA, TPP1, DMD and COL17A1 genes, respectively. Combination of CC-90009 with aminoglycosides such as gentamicin or ELX-02 may have potential for PTC readthrough therapy.
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Affiliation(s)
- Alireza Baradaran-Heravi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Aruna D Balgi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Sara Hosseini-Farahabadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Kunho Choi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Cristina Has
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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19
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Belinky F, Ganguly I, Poliakov E, Yurchenko V, Rogozin IB. Analysis of Stop Codons within Prokaryotic Protein-Coding Genes Suggests Frequent Readthrough Events. Int J Mol Sci 2021; 22:ijms22041876. [PMID: 33672790 PMCID: PMC7918605 DOI: 10.3390/ijms22041876] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/05/2021] [Accepted: 02/09/2021] [Indexed: 02/07/2023] Open
Abstract
Nonsense mutations turn a coding (sense) codon into an in-frame stop codon that is assumed to result in a truncated protein product. Thus, nonsense substitutions are the hallmark of pseudogenes and are used to identify them. Here we show that in-frame stop codons within bacterial protein-coding genes are widespread. Their evolutionary conservation suggests that many of them are not pseudogenes, since they maintain dN/dS values (ratios of substitution rates at non-synonymous and synonymous sites) significantly lower than 1 (this is a signature of purifying selection in protein-coding regions). We also found that double substitutions in codons—where an intermediate step is a nonsense substitution—show a higher rate of evolution compared to null models, indicating that a stop codon was introduced and then changed back to sense via positive selection. This further supports the notion that nonsense substitutions in bacteria are relatively common and do not necessarily cause pseudogenization. In-frame stop codons may be an important mechanism of regulation: Such codons are likely to cause a substantial decrease of protein expression levels.
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Affiliation(s)
- Frida Belinky
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA; (F.B.); (I.G.)
| | - Ishan Ganguly
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA; (F.B.); (I.G.)
| | - Eugenia Poliakov
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, 710 00 Ostrava, Czech Republic
- Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, 119435 Moscow, Russia
- Correspondence: (V.Y.); (I.B.R.)
| | - Igor B. Rogozin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA; (F.B.); (I.G.)
- Correspondence: (V.Y.); (I.B.R.)
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20
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Elia N. Using unnatural amino acids to selectively label proteins for cellular imaging: a cell biologist viewpoint. FEBS J 2020; 288:1107-1117. [PMID: 32640070 PMCID: PMC7983921 DOI: 10.1111/febs.15477] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/16/2020] [Accepted: 07/03/2020] [Indexed: 12/12/2022]
Abstract
Twenty-five years ago, GFP revolutionized the field of cell biology by enabling scientists to visualize, for the first time, proteins in living cells. However, when it comes to current, state-of-the-art imaging technologies, fluorescent proteins (such as GFP) have several limitations that result from their size and photophysics. Over the past decade, an elegant, alternative approach, which is based on the direct labeling of proteins with fluorescent dyes and is compatible with live-cell and super-resolution imaging applications, has been introduced. In this approach, an unnatural amino acid that can covalently bind a fluorescent dye is incorporated into the coding sequence of a protein. The protein of interest is thereby site-specifically fluorescently labeled inside the cell, eliminating the need for protein- or peptide-labeling tags. Whether this labeling approach will change cell biology research is currently unclear, but it clearly has the potential to do so. In this short review, a general overview of this approach is provided, focusing on the imaging of site-specifically labeled proteins in mammalian tissue culture cells, and highlighting its advantages and limitations for cellular imaging.
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Affiliation(s)
- Natalie Elia
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.,National Institute for Biotechnology in the Negev (NIBN), Ben-Gurion University of the Negev, Beer Sheva, Israel
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