1
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Diao F, Vasudevan D, Heckscher ES, White BH. Hox gene-specific cellular targeting using split intein Trojan exons. Proc Natl Acad Sci U S A 2024; 121:e2317083121. [PMID: 38602904 PMCID: PMC11047080 DOI: 10.1073/pnas.2317083121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 03/07/2024] [Indexed: 04/13/2024] Open
Abstract
The Trojan exon method, which makes use of intronically inserted T2A-Gal4 cassettes, has been widely used in Drosophila to create thousands of gene-specific Gal4 driver lines. These dual-purpose lines provide genetic access to specific cell types based on their expression of a native gene while simultaneously mutating one allele of the gene to enable loss-of-function analysis in homozygous animals. While this dual use is often an advantage, the truncation mutations produced by Trojan exons are sometimes deleterious in heterozygotes, perhaps by creating translation products with dominant negative effects. Such mutagenic effects can cause developmental lethality as has been observed with genes encoding essential transcription factors. Given the importance of transcription factors in specifying cell type, alternative techniques for generating specific Gal4 lines that target them are required. Here, we introduce a modified Trojan exon method that retains the targeting fidelity and plug-and-play modularity of the original method but mitigates its mutagenic effects by exploiting the self-splicing capabilities of split inteins. "Split Intein Trojan exons" (siTrojans) ensure that the two truncation products generated from the interrupted allele of the native gene are trans-spliced to create a full-length native protein. We demonstrate the efficacy of siTrojans by generating a comprehensive toolkit of Gal4 and Split Gal4 lines for the segmentally expressed Hox transcription factors and illustrate their use in neural circuit mapping by targeting neurons according to their position along the anterior-posterior axis. Both the method and the Hox gene-specific toolkit introduced here should be broadly useful.
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Affiliation(s)
- Fengqiu Diao
- Laboratory of Molecular Biology, Section on Neural Function, National Institute of Mental Health, NIH, Bethesda, MD20892
| | - Deeptha Vasudevan
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL60637
| | - Ellie S. Heckscher
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL60637
| | - Benjamin H. White
- Laboratory of Molecular Biology, Section on Neural Function, National Institute of Mental Health, NIH, Bethesda, MD20892
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2
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Son A, Smetana JS, Horowitz S, Lennon CW. An intein-based biosensor to measure protein stability in vivo. Protein Sci 2024; 33:e4925. [PMID: 38380775 PMCID: PMC10880411 DOI: 10.1002/pro.4925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/10/2024] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
Biosensors to measure protein stability in vivo are valuable tools for a variety of applications. Previous work has demonstrated that a tripartite design, whereby a protein of interest (POI) is inserted within a reporter, can link POI stability to reporter activity. Inteins are translated within other proteins and excised in a self-mediated protein splicing reaction. Here, we developed a novel folding biosensor where a POI is inserted within an intein, which is subsequently translated within an antibiotic resistance marker. We showed that protein splicing is required for antibiotic resistance and that housing a stable POI within the intein, compared to an unstable variant, results in a 100,000-fold difference in survival. Further, using a fluorescent protein that matures slowly as the POI, we developed a reporter with two simultaneous readouts for protein folding. Finally, we showed that co-expression of GroEL can significantly increase the activity of both reporters, further verifying that protein folding factors can act on the POI in the biosensor. As a whole, our work provides a new twist on the traditional tripartite approach to measuring protein stability in vivo.
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Affiliation(s)
- Ahyun Son
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy AgingUniversity of DenverDenverColoradoUSA
| | - John S. Smetana
- Department of Biological SciencesMurray State UniversityMurrayKentuckyUSA
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy AgingUniversity of DenverDenverColoradoUSA
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3
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Mariano A, Di Cristofano S, Raimondo D, Scotto d'Abusco A. Split Gp41-1 intein splicing as a model to evaluate the cellular location of the oncosuppressor Maspin in an in vitro model of osteosarcoma. Cell Biochem Funct 2024; 42:e3987. [PMID: 38509770 DOI: 10.1002/cbf.3987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/06/2024] [Accepted: 03/10/2024] [Indexed: 03/22/2024]
Abstract
Inteins are proteins involved in the protein splicing mechanism, an autoprocessing event, where sequences (exteins) separated by inteins become ligated each other after recombination. Two kinds of inteins have been described, contiguous inteins and split inteins. The former ones are transcribed and translated as a single peptide along with their exteins, while the latter are fragmented between two different genes and are transcribed and translated separately. The aim of this study is to establish a method to obtain a fluorescent eukaryotic protein to analyze its cellular localization, using the natural split gp41-1 inteins. We chose natural split inteins due to their distribution in all three domains of life. Two constructs were prepared, one containing the N-terminal split intein along with the N-moiety of the Red Fluorescent Protein (RFP) and a second construct containing the C-terminal of split intein, the C-moiety of RFP and the gene coding for Maspin, a tumor suppressor protein. The trans-splicing was verified by transfecting both N-terminal and C-terminal constructs into mammalian cells. The success of the recombination event was highlighted through the fluorescence produced by reconstituted RFP after recombination, along with the overlap of the red fluorescence produced by recombined RFP and the green fluorescence produced by the hybridization of the recombinant Maspin with a specific antibody. In conclusion, we opted to use this mechanism of recombination to obtain a fluorescent Maspin instead to express a large fusion protein, considering that it could interfere with Maspin's structure and function.
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Affiliation(s)
- Alessia Mariano
- Department. of Biochemical Sciences, Sapienza University of Roma, Rome, Italy
| | | | - Domenico Raimondo
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
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4
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Foo GW, Leichthammer CD, Saita IM, Lukas ND, Batko IZ, Heinrichs DE, Edgell DR. Intein-based thermoregulated meganucleases for containment of genetic material. Nucleic Acids Res 2024; 52:2066-2077. [PMID: 38180814 PMCID: PMC10899782 DOI: 10.1093/nar/gkad1247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 01/07/2024] Open
Abstract
Limiting the spread of synthetic genetic information outside of the intended use is essential for applications where biocontainment is critical. In particular, biocontainment of engineered probiotics and plasmids that are excreted from the mammalian gastrointestinal tract is needed to prevent escape and acquisition of genetic material that could confer a selective advantage to microbial communities. Here, we built a simple and lightweight biocontainment system that post-translationally activates a site-specific DNA endonuclease to degrade DNA at 18°C and not at higher temperatures. We constructed an orthogonal set of temperature-sensitive meganucleases (TSMs) by inserting the yeast VMA1 L212P temperature-sensitive intein into the coding regions of LAGLIDADG homing endonucleases. We showed that the TSMs eliminated plasmids carrying the cognate TSM target site from laboratory strains of Escherichia coli at the permissive 18°C but not at higher restrictive temperatures. Plasmid elimination is dependent on both TSM endonuclease activity and intein splicing. TSMs eliminated plasmids from E. coli Nissle 1917 after passage through the mouse gut when fecal resuspensions were incubated at 18°C but not at 37°C. Collectively, our data demonstrates the potential of thermoregulated meganucleases as a means of restricting engineered plasmids and probiotics to the mammalian gut.
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Affiliation(s)
- Gary W Foo
- Department of Biochemistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | | | - Ibrahim M Saita
- Department of Biochemistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - Nicholas D Lukas
- Department of Biochemistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - Izabela Z Batko
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - David E Heinrichs
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - David R Edgell
- Department of Biochemistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
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5
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Dhayalan B, Kent SBH, Fetter-Pruneda I. A Chemical Counterpart to the Resolution Step of Nature's Intein-Mediated Protein Splicing. ACS Chem Biol 2024; 19:9-14. [PMID: 38096499 PMCID: PMC10804359 DOI: 10.1021/acschembio.3c00590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/29/2023] [Accepted: 12/01/2023] [Indexed: 01/23/2024]
Abstract
In the course of an attempted total chemical synthesis of the ant insulin-like peptide-2 (ILP2) protein molecule, specific cleavage of a backbone peptide bond in a branched ester-linked polypeptide chain with concomitant peptide splicing was observed. The side reaction was investigated in model compounds. Here, we postulate a chemical mechanism for this novel polypeptide backbone cleavage reaction as a chemical counterpart to the resolution step of biochemical intein-mediated protein splicing.
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Affiliation(s)
- Balamurugan Dhayalan
- Department
of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - Stephen B. H. Kent
- Department
of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - Ingrid Fetter-Pruneda
- Laboratory
of Social Evolution and Behavior, The Rockefeller
University, 1230 York
Avenue, New York, New York 10065, United States
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6
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Karasev MM, Verkhusha VV, Shcherbakova DM. Near-Infrared Optogenetic Module for Conditional Protein Splicing. J Mol Biol 2023; 435:168360. [PMID: 37949312 PMCID: PMC10842711 DOI: 10.1016/j.jmb.2023.168360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 10/29/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
Optogenetics has emerged as a powerful tool for spatiotemporal control of biological processes. Near-infrared (NIR) light, with its low phototoxicity and deep tissue penetration, holds particular promise. However, the optogenetic control of polypeptide bond formation has not yet been developed. In this study, we introduce a NIR optogenetic module for conditional protein splicing (CPS) based on the gp41-1 intein. We optimized the module to minimize background signals in the darkness and to maximize the contrast between light and dark conditions. Next, we engineered a NIR CPS gene expression system based on the protein ligation of a transcription factor. We applied the NIR CPS for light-triggered protein cleavage to activate gasdermin D, a pore-forming protein that induces pyroptotic cell death. Our NIR CPS optogenetic module represents a promising tool for controlling molecular processes through covalent protein linkage and cleavage.
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Affiliation(s)
- Maksim M Karasev
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
| | - Vladislav V Verkhusha
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland; Department of Genetics, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Daria M Shcherbakova
- Department of Genetics, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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7
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Gallot-Lavallée L, Jerlström-Hultqvist J, Zegarra-Vidarte P, Salas-Leiva DE, Stairs CW, Čepička I, Roger AJ, Archibald JM. Massive intein content in Anaeramoeba reveals aspects of intein mobility in eukaryotes. Proc Natl Acad Sci U S A 2023; 120:e2306381120. [PMID: 38019867 DOI: 10.1073/pnas.2306381120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023] Open
Abstract
Inteins are self-splicing protein elements found in viruses and all three domains of life. How the DNA encoding these selfish elements spreads within and between genomes is poorly understood, particularly in eukaryotes where inteins are scarce. Here, we show that the nuclear genomes of three strains of Anaeramoeba encode between 45 and 103 inteins, in stark contrast to four found in the most intein-rich eukaryotic genome described previously. The Anaeramoeba inteins reside in a wide range of proteins, only some of which correspond to intein-containing proteins in other eukaryotes, prokaryotes, and viruses. Our data also suggest that viruses have contributed to the spread of inteins in Anaeramoeba and the colonization of new alleles. The persistence of Anaeramoeba inteins might be partly explained by intragenomic movement of intein-encoding regions from gene to gene. Our intein dataset greatly expands the spectrum of intein-containing proteins and provides insights into the evolution of inteins in eukaryotes.
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Affiliation(s)
- Lucie Gallot-Lavallée
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Jon Jerlström-Hultqvist
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Microbiology and Immunology, Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Uppsala 751 24, Sweden
| | - Paula Zegarra-Vidarte
- Microbiology and Immunology, Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Uppsala 751 24, Sweden
| | - Dayana E Salas-Leiva
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Courtney W Stairs
- Microbiology Group, Department of Biology, Lund University, Lund 223 62, Sweden
| | - Ivan Čepička
- Department of Zoology, Charles University, Prague 128 00, Czech Republic
| | - Andrew J Roger
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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8
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Prabhala SV, Mayone SA, Moody NM, Kanu CB, Wood DW. A Convenient Self-Removing Affinity Tag Method for the Simple Purification of Tagless Recombinant Proteins. Curr Protoc 2023; 3:e901. [PMID: 37882966 PMCID: PMC10605964 DOI: 10.1002/cpz1.901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
In this work, we describe a novel self-cleaving affinity tag technology based on a highly modified split-intein cleaving element. In this system, which has recently been commercialized by Protein Capture Science, LLC under the name iCapTagTM , the N-terminal segment of an engineered split intein is covalently immobilized onto a capture resin, while the smaller C-terminal intein segment is fused to the N-terminus of the desired target protein. The tagged target can then be expressed in an appropriate expression system, without concern for premature intein cleaving. During the purification, strong binding between the intein segments effectively captures the tagged target onto the capture resin while simultaneously generating a cleaving-competent intein complex. After unwanted impurities are washed from the resin, cleavage of the target protein is initiated by a shift of the buffer pH from 8.5 to 6.2. As a result, the highly purified tagless target protein is released from the column in the elution step. Alternately, the resin beads can be added directly to cell culture broth or lysate, allowing capture, purification and cleavage of the tagless target protein using a column-free format. These methods result in highly pure tagless target protein in a single step, and can thereby accelerate characterization and functional studies. In this work we demonstrate the single step purification of streptokinase, a fibrinolytic agent, and an engineered recombinant human hemoglobin 1.1 (rHb1.1). © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Expression of high-titer protein tagged with the Nostoc punctiforme (Npu) DnaE split-intein on the N-terminus Basic Protocol 2: Purification of high-titer protein using the Nostoc punctiforme (Npu) DnaE split-intein purification platform Alternate Protocol 1: Expression of low-titer protein tagged with the Nostoc punctiforme (Npu) DnaE split-intein on the N-terminus Alternate Protocol 2: Purification of low-titer protein using the Nostoc punctiforme (Npu) DnaE split-intein purification platform.
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Affiliation(s)
- Sai Vivek Prabhala
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Sophia A Mayone
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Nathan M Moody
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Chidinma B Kanu
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - David W Wood
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
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Yamada R, Nakahara I, Kumagai I, Asano R, Nakanishi T, Makabe K. Construction of IgG-Fab 2 bispecific antibody via intein-mediated protein trans-splicing reaction. Sci Rep 2023; 13:15961. [PMID: 37749185 PMCID: PMC10520027 DOI: 10.1038/s41598-023-43110-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 09/20/2023] [Indexed: 09/27/2023] Open
Abstract
A bispecific antibody (bsAb) is a class of engineered antibody molecules that simultaneously binds to two different antigens by having two kinds of antigen-binding domains. One of the major obstacles for the bsAb production is the incorrect chain-pairing problem, wherein each heavy and light chain should form pairings with the correct counterpart's chains, but the structural similarity of the incorrect partners also forms the incorrect pairings. This study aimed to demonstrate a bsAb construction method using intein-mediated protein trans-splicing to create IgG-Fab2-type bsAbs, which is a modified antibody with a structure in which two additional Fabs are linked to the N-terminus of the heavy chain of an IgG molecule. The chain-paring problem between a heavy chain and a light chain is circumvented by separate expression and purification of the IgG part and the Fab part. We found that the deletion of a possible glycosylation residue improved the reaction yield and side-reaction cleavage in the protein ligation step. The resulting bsAb, IgG-Fab2 (Her2/CD3), demonstrated target binding activity and cytotoxicity mediated by activated T cells. These results indicate that the use of the protein ligation to produce the IgG-Fab2 type bsAb will expand the bsAb production method.
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Affiliation(s)
- Risa Yamada
- Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa, Yamagata, 992-8510, Japan
| | - Ishin Nakahara
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 183-8538, Japan
| | - Izumi Kumagai
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 183-8538, Japan
| | - Ryutaro Asano
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 183-8538, Japan
| | - Takeshi Nakanishi
- Division of Science and Engineering for Materials, Chemistry and Biology, Department of Chemistry and Bioengineering, Graduate School of Engineering, Osaka Metropolitan University, Sugimoto 3-3-138, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Koki Makabe
- Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa, Yamagata, 992-8510, Japan.
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10
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Zhang B, Zheng Y, Chu G, Deng X, Wang T, Shi W, Zhou Y, Tang S, Zheng JS, Liu L. Backbone-Installed Split Intein-Assisted Ligation for the Chemical Synthesis of Mirror-Image Proteins. Angew Chem Int Ed Engl 2023; 62:e202306270. [PMID: 37357888 DOI: 10.1002/anie.202306270] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/25/2023] [Accepted: 06/26/2023] [Indexed: 06/27/2023]
Abstract
Membrane-associated D-proteins are an important class of synthetic molecules needed for D-peptide drug discovery, but their chemical synthesis using canonical ligation methods such as native chemical ligation is often hampered by the poor solubility of their constituent peptide segments. Here, we describe a Backbone-Installed Split Intein-Assisted Ligation (BISIAL) method for the synthesis of these proteins, wherein the native L-forms of the N- and C-intein fragments of the unique consensus-fast (Cfa) (i.e. L-CfaN and L-CfaC ) are separately installed onto the two D-peptide segments to be ligated via a removable backbone modification. The ligation proceeds smoothly at micromolar (μM) concentrations under strongly chaotropic conditions (8.0 M urea), and the subsequent removal of the backbone modification groups affords the desired D-proteins without leaving any "ligation scar" on the products. The effectiveness and practicality of the BISIAL method are exemplified by the synthesis of the D-enantiomers of the extracellular domains of T cell immunoglobulin and ITIM domain (TIGIT) and tropomyosin receptor kinase C (TrkC). The BISIAL method further expands the chemical protein synthesis ligation toolkit and provides practical access to challenging D-protein targets.
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Affiliation(s)
- Baochang Zhang
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yupeng Zheng
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Guochao Chu
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Xiangyu Deng
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Tongyue Wang
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Weiwei Shi
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yongkang Zhou
- The First Affiliated Hospital of USTC, MOE Key Laboratory of Cellular Dynamics, and Division of Life Sciences and Medicine, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Shan Tang
- The First Affiliated Hospital of USTC, MOE Key Laboratory of Cellular Dynamics, and Division of Life Sciences and Medicine, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Ji-Shen Zheng
- The First Affiliated Hospital of USTC, MOE Key Laboratory of Cellular Dynamics, and Division of Life Sciences and Medicine, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230001, China
| | - Lei Liu
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Center for Synthetic and Systems Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
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11
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Zhan Q, Shi C, Jiang Y, Gao X, Lin Y. Efficient splicing of the CPE intein derived from directed evolution of the Cryptococcus neoformans PRP8 intein. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1310-1318. [PMID: 37489009 PMCID: PMC10448054 DOI: 10.3724/abbs.2023135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/19/2023] [Indexed: 07/26/2023] Open
Abstract
Intein-mediated protein splicing has been widely used in protein engineering; however, the splicing efficiency and extein specificity usually limit its further application. Thus, there is a demand for more general inteins that can overcome these limitations. Here, we study the trans-splicing of CPE intein obtained from the directed evolution of Cne PRP8, which shows that its splicing rate is ~29- fold higher than that of the wild-type. When the +1 residue of C-extein is changed to cysteine, CPE also shows high splicing activity. Faster association and higher affinity may contribute to the high splicing rate compared with wild-type intein. These findings have important implications for the future engineering of inteins and provide clues for fundamental studies of protein structure and folding.
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Affiliation(s)
- Qin Zhan
- College of Biological Science and Medical EngineeringDonghua UniversityShanghai201620China
| | - Changhua Shi
- College of Biological Science and Medical EngineeringDonghua UniversityShanghai201620China
| | - Yu Jiang
- College of Biological Science and Medical EngineeringDonghua UniversityShanghai201620China
| | - Xianling Gao
- Shandong Guoli Biotechnology Co.Ltd.Jinan250101China
| | - Ying Lin
- College of Biological Science and Medical EngineeringDonghua UniversityShanghai201620China
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12
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Wang Y, Shi Y, Hellinga HW, Beese LS. Thermally controlled intein splicing of engineered DNA polymerases provides a robust and generalizable solution for accurate and sensitive molecular diagnostics. Nucleic Acids Res 2023; 51:5883-5894. [PMID: 37166959 PMCID: PMC10287962 DOI: 10.1093/nar/gkad368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/18/2023] [Accepted: 05/09/2023] [Indexed: 05/12/2023] Open
Abstract
DNA polymerases are essential for nucleic acid synthesis, cloning, sequencing and molecular diagnostics technologies. Conditional intein splicing is a powerful tool for controlling enzyme reactions. We have engineered a thermal switch into thermostable DNA polymerases from two structurally distinct polymerase families by inserting a thermally activated intein domain into a surface loop that is integral to the polymerase active site, thereby blocking DNA or RNA template access. The fusion proteins are inactive, but retain their structures, such that the intein excises during a heat pulse delivered at 70-80°C to generate spliced, active polymerases. This straightforward thermal activation step provides a highly effective, one-component 'hot-start' control of PCR reactions that enables accurate target amplification by minimizing unwanted by-products generated by off-target reactions. In one engineered enzyme, derived from Thermus aquaticus DNA polymerase, both DNA polymerase and reverse transcriptase activities are controlled by the intein, enabling single-reagent amplification of DNA and RNA under hot-start conditions. This engineered polymerase provides high-sensitivity detection for molecular diagnostics applications, amplifying 5-6 copies of the tested DNA and RNA targets with >95% certainty. The design principles used to engineer the inteins can be readily applied to construct other conditionally activated nucleic acid processing enzymes.
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Affiliation(s)
- You Wang
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Yuqian Shi
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Homme W Hellinga
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Lorena S Beese
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
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13
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Ewen-Campen B, Luan H, Xu J, Singh R, Joshi N, Thakkar T, Berger B, White BH, Perrimon N. split-intein Gal4 provides intersectional genetic labeling that is repressible by Gal80. Proc Natl Acad Sci U S A 2023; 120:e2304730120. [PMID: 37276389 PMCID: PMC10268248 DOI: 10.1073/pnas.2304730120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/10/2023] [Indexed: 06/07/2023] Open
Abstract
The split-Gal4 system allows for intersectional genetic labeling of highly specific cell types and tissues in Drosophila. However, the existing split-Gal4 system, unlike the standard Gal4 system, cannot be repressed by Gal80, and therefore cannot be controlled temporally. This lack of temporal control precludes split-Gal4 experiments in which a genetic manipulation must be restricted to specific timepoints. Here, we describe a split-Gal4 system based on a self-excising split-intein, which drives transgene expression as strongly as the current split-Gal4 system and Gal4 reagents, yet which is repressible by Gal80. We demonstrate the potent inducibility of "split-intein Gal4" in vivo using both fluorescent reporters and via reversible tumor induction in the gut. Further, we show that our split-intein Gal4 can be extended to the drug-inducible GeneSwitch system, providing an independent method for intersectional labeling with inducible control. We also show that the split-intein Gal4 system can be used to generate highly cell type-specific genetic drivers based on in silico predictions generated by single-cell RNAseq (scRNAseq) datasets, and we describe an algorithm ("Two Against Background" or TAB) to predict cluster-specific gene pairs across multiple tissue-specific scRNA datasets. We provide a plasmid toolkit to efficiently create split-intein Gal4 drivers based on either CRISPR knock-ins to target genes or using enhancer fragments. Altogether, the split-intein Gal4 system allows for the creation of highly specific intersectional genetic drivers that are inducible/repressible.
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Affiliation(s)
- Ben Ewen-Campen
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA02115
| | - Haojiang Luan
- Laboratory of Molecular Biology, National Institute of Mental Health, NIH, Bethesda, MD20892
| | - Jun Xu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA02115
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai200032, China
| | - Rohit Singh
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Neha Joshi
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA02115
| | - Tanuj Thakkar
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA02115
| | - Bonnie Berger
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA02139
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA02143
| | - Benjamin H. White
- Laboratory of Molecular Biology, National Institute of Mental Health, NIH, Bethesda, MD20892
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA02115
- HHMI, Boston, MA02115
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14
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Ray DM, Flood JR, David Y. Harnessing Split-Inteins as a Tool for the Selective Modification of Surface Receptors in Live Cells. Chembiochem 2023; 24:e202200487. [PMID: 36178424 PMCID: PMC9977608 DOI: 10.1002/cbic.202200487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/29/2022] [Indexed: 02/04/2023]
Abstract
Biochemical studies of integral membrane proteins are often hampered by low purification yields and technical limitations such as aggregation causing in vitro manipulations to be challenging. The ability of controlling proteins in live cells bypasses these limitations while broadening the scope of accessible questions owing to the proteins being in their native environment. Here we take advantage of the intein biorthogonality to mammalian systems, site specificity, fast kinetics, and auto-processing nature as an attractive option for modifying surface proteins. Using EGFR as a model, we demonstrate that the split-intein pair AvaN /NpuC can be used to efficiently and specifically modify target membrane proteins with a synthetic adduct for downstream live cell application.
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Affiliation(s)
- Devin M Ray
- Tri-Institutional PhD Program in Chemical Biology, New York, NY, 10065, USA
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Tri-Institutional MD-PhD Program, New York, NY 10065, USA
| | - Julia R Flood
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Yael David
- Tri-Institutional PhD Program in Chemical Biology, New York, NY, 10065, USA
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medical College, New York, NY, 10065, USA
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15
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Kim YE, Kim S, Kim IH. Neural circuit-specific gene manipulation in mouse brain in vivo using split-intein-mediated split-Cre system. STAR Protoc 2022; 3:101807. [PMID: 36386891 PMCID: PMC9641071 DOI: 10.1016/j.xpro.2022.101807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neural network studies require efficient genetic tools to analyze individual neural circuit functions in vivo. Thus, we developed an advanced circuit-selective gene manipulating tool utilizing anterograde and retrograde adeno-associated viruses (AAVs) encoding split-intein-mediated split-Cre. This strategy can be applied to visualize a specific neural circuit as well as manipulate multiple genes in the circuit neurons. Here, we describe the production and purification of the AAVs, viral injection to the mouse brain, and imaging analysis for a specific neural circuit. For complete details on the use and execution of this protocol, please refer to Kim et al. (2022). In vivo application of the split-intein/split-Cre system using mouse models Split-Cre reconstitution system for neural circuit-specific gene manipulation Robust and highly specific unidirectional neural circuit-selective Cre expression Simultaneous manipulation of multiple genes in a specific unidirectional neural circuit
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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Affiliation(s)
- Yong-Eun Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| | - Sunwhi Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| | - Il Hwan Kim
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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16
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Sekar G, Stevens AJ, Mostafavi AZ, Sashi P, Muir TW, Cowburn D. A Conserved Histidine Residue Drives Extein Dependence in an Enhanced Atypically Split Intein. J Am Chem Soc 2022; 144:19196-19203. [PMID: 36194550 PMCID: PMC10241006 DOI: 10.1021/jacs.2c08985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Split intein-mediated protein trans-splicing (PTS) is widely applied in chemical biology and biotechnology to carry out traceless and specific protein ligation. However, the external residues immediately flanking the intein (exteins) can reduce the splicing rate, thereby limiting certain applications of PTS. Splicing by a recently developed intein with atypical split architecture ("Cat") exhibits a stark dependence on the sequence of its N-terminal extein residues. Here, we further developed Cat using error-prone polymerase chain reaction (PCR) and a cell-based selection assay to produce Cat*, which exhibits greatly enhanced PTS activity in the presence of unfavorable N-extein residues. We then applied solution nuclear magnetic resonance spectroscopy and molecular dynamics simulations to explore how the dynamics of a conserved B-block histidine residue (His78) contribute to this extein dependence. The enhanced extein tolerance of Cat* reported here should expand the applicability of atypically split inteins, and the mechanism highlights common principles that contribute to extein dependence.
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Affiliation(s)
- Giridhar Sekar
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | - Adam J. Stevens
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, USA
| | - Anahita Z. Mostafavi
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, USA
| | - Pulikallu Sashi
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | - Tom W. Muir
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, USA
| | - David Cowburn
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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17
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Heikkinen HA, Aranko AS, Iwaï H. The NMR structure of the engineered halophilic DnaE intein for segmental isotopic labeling using conditional protein splicing. J Magn Reson 2022; 338:107195. [PMID: 35398651 DOI: 10.1016/j.jmr.2022.107195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 03/02/2022] [Accepted: 03/13/2022] [Indexed: 06/14/2023]
Abstract
Protein trans-splicing catalyzed by split inteins has been used for segmental isotopic labeling of proteins for alleviating the complexity of NMR signals. Whereas inteins spontaneously trigger protein splicing upon protein folding, inteins from extremely halophilic organisms require a high salinity condition to induce protein splicing. We designed and created a salt-inducible intein from the widely used DnaE intein from Nostoc punctiforme by introducing 29 mutations, which required a lower salt concentration than naturally occurring halo-obligate inteins. We determined the NMR solution structure of the engineered salt-inducible DnaE intein in 2 M NaCl, showing the essentially identical three-dimensional structure to the original one, albeit it unfolds without salts. The NMR structure of a halo-obligate intein under high salinity suggests that the stabilization of the active folded conformation is not a mere result of various intramolecular interactions but the subtle energy balance from the complex interactions, including the solvation energy, which involve waters, ions, co-solutes, and protein polypeptide chains.
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Affiliation(s)
- Harri A Heikkinen
- Institute of Biotechnology, University of Helsinki, PO Box 65, Helsinki, FIN-00014, Finland
| | - A Sesilja Aranko
- Institute of Biotechnology, University of Helsinki, PO Box 65, Helsinki, FIN-00014, Finland.
| | - Hideo Iwaï
- Institute of Biotechnology, University of Helsinki, PO Box 65, Helsinki, FIN-00014, Finland.
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18
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Yalala VR, Lynch AK, Mills KV. Conditional Alternative Protein Splicing Promoted by Inteins from Haloquadratum walsbyi. Biochemistry 2022; 61:294-302. [PMID: 35073064 PMCID: PMC8847336 DOI: 10.1021/acs.biochem.1c00788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Protein splicing is a post-translational process by which an intervening protein, or an intein, catalyzes its own excision from flanking polypeptides, or exteins, coupled to extein ligation. Four inteins interrupt the MCM helicase of the halophile Haloquadratum walsbyi, two of which are mini-inteins that lack a homing endonuclease. Both inteins can be overexpressed in Escherichia coli and purified as unspliced precursors; splicing can be induced in vitro by incubation with salt. However, one intein can splice in 0.5 M NaCl in vitro, whereas the other splices efficiently only in buffer containing over 2 M NaCl; the organism also requires high salt to grow, with the standard growth media containing over 3 M NaCl and about 0.75 M magnesium salts. Consistent with this difference in salt-dependent activity, an intein-containing precursor protein with both inteins promotes conditional alternative protein splicing (CAPS) to yield different spliced products dependent on the salt concentration. Native Trp fluorescence of the inteins suggests that the difference in activity may be due to partial unfolding of the inteins at lower salt concentrations. This differential salt sensitivity of intein activity may provide a useful mechanism for halophiles to respond to environmental changes.
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Affiliation(s)
- Vaishnavi R Yalala
- Department of Chemistry, College of the Holy Cross, 1 College Street, Worcester, Massachusetts 01610, United States
| | - Abigeal K Lynch
- Department of Chemistry, College of the Holy Cross, 1 College Street, Worcester, Massachusetts 01610, United States
| | - Kenneth V Mills
- Department of Chemistry, College of the Holy Cross, 1 College Street, Worcester, Massachusetts 01610, United States
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19
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Lan Y, Zhang K, He T, Wang H, Jiang C, Yan H, Xiang Y. Systematic analysis of the Serine/Arginine-Rich Protein Splicing Factors (SRs) and focus on salt tolerance of PtSC27 in Populus trichocarpa. Plant Physiol Biochem 2022; 173:97-109. [PMID: 35121529 DOI: 10.1016/j.plaphy.2022.01.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 01/09/2022] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Serine/Arginine-Rich Protein Splicing Factors (SRs) are indispensable splicing factors, which play significant roles in spliceosome assembly, splicing regulation and regulation of plant stress. However, a comprehensive analysis and function research of SRs in the woody plant is still lacking. In this report, we conducted the identification and comprehensive analysis of the 71 SRs in poplar and three other dicots, including basic characterization, phylogenetic, conserved motifs, gene duplication, promoter and splice isoform of these genes. Based on the publicly available transcriptome data, expression pattern of SRs in poplar under low temperature, high temperature, drought and salt stress were further analyzed. Subsequently, a key candidate gene PtSC27 that responded to salt stress was screened. More importantly, overexpression of PtSC27 increased plant survival rate under salt stress, and enhanced salt tolerance by regulating malondialdehyde (MDA) content, peroxidase (POD) and catalase (CAT) enzyme activities in transgenic plants. Meanwhile, overexpression of PtSC27 made transgenic plants insensitive to exogenous ABA and improved the expression of some ABA signal-related genes under salt stress. Overall, our studies lay a foundation for understanding the structure and function of SRs in the poplar and provide useful gene resources for breeding through genetic engineering.
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Affiliation(s)
- Yangang Lan
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China
| | - Kaimei Zhang
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China
| | - Ting He
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China
| | - Hao Wang
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China
| | - Chengzhi Jiang
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China
| | - Hanwei Yan
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China.
| | - Yan Xiang
- Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China.
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20
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Bryson JW, Auxillos JY, Rosser SJ. Multiplexed activation in mammalian cells using a split-intein CRISPR/Cas12a based synthetic transcription factor. Nucleic Acids Res 2022; 50:549-560. [PMID: 34908140 PMCID: PMC8754635 DOI: 10.1093/nar/gkab1191] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/15/2021] [Accepted: 11/26/2021] [Indexed: 01/09/2023] Open
Abstract
The adoption of CRISPR systems for the generation of synthetic transcription factors has greatly simplified the process for upregulating endogenous gene expression, with a plethora of applications in cell biology, bioproduction and cell reprogramming. The recently discovered CRISPR/Cas12a (Cas12a) systems offer extended potential, as Cas12a is capable of processing its own crRNA array, to provide multiple individual crRNAs for subsequent targeting from a single transcript. Here we show the application of dFnCas12a-VPR in mammalian cells, with the Francisella novicida Cas12a (FnCas12a) possessing a shorter PAM sequence than Acidaminococcus sp. (As) or Lachnospiraceae bacterium (Lb) variants, enabling denser targeting of genomic loci, while performing just as well or even better than the other variants. We observe that synergistic activation and multiplexing can be achieved using crRNA arrays but also show that crRNAs expressed towards the 5' of 6-crRNA arrays show evidence of enhanced activity. This not only represents a more flexible tool for transcriptional modulation but further expands our understanding of the design capabilities and limitations when considering longer crRNA arrays for multiplexed targeting.
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Affiliation(s)
- James W Bryson
- Department of Quantitative Biology, Biochemistry and Biotechnology, University of Edinburgh, Edinburgh, UK
- Centre for Synthetic and Systems Biology and UK Centre for Mammalian Synthetic Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Jamie Y Auxillos
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Susan J Rosser
- Department of Quantitative Biology, Biochemistry and Biotechnology, University of Edinburgh, Edinburgh, UK
- Centre for Synthetic and Systems Biology and UK Centre for Mammalian Synthetic Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
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21
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Morrison MS, Wang T, Raguram A, Hemez C, Liu DR. Disulfide-compatible phage-assisted continuous evolution in the periplasmic space. Nat Commun 2021; 12:5959. [PMID: 34645844 PMCID: PMC8514426 DOI: 10.1038/s41467-021-26279-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/27/2021] [Indexed: 11/18/2022] Open
Abstract
The directed evolution of antibodies has yielded important research tools and human therapeutics. The dependence of many antibodies on disulfide bonds for stability has limited the application of continuous evolution technologies to antibodies and other disulfide-containing proteins. Here we describe periplasmic phage-assisted continuous evolution (pPACE), a system for continuous evolution of protein-protein interactions in the disulfide-compatible environment of the E. coli periplasm. We first apply pPACE to rapidly evolve novel noncovalent and covalent interactions between subunits of homodimeric YibK protein and to correct a binding-defective mutant of the anti-GCN4 Ω-graft antibody. We develop an intein-mediated system to select for soluble periplasmic expression in pPACE, leading to an eight-fold increase in soluble expression of the Ω-graft antibody. Finally, we evolve disulfide-containing trastuzumab antibody variants with improved binding to a Her2-like peptide and improved soluble expression. Together, these results demonstrate that pPACE can rapidly optimize proteins containing disulfide bonds, broadening the applicability of continuous evolution.
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Affiliation(s)
- Mary S Morrison
- Merkin Institute of Transformative Technologies in Health Care, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, 02138, USA
| | - Tina Wang
- Merkin Institute of Transformative Technologies in Health Care, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, 02138, USA
| | - Aditya Raguram
- Merkin Institute of Transformative Technologies in Health Care, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, 02138, USA
| | - Colin Hemez
- Merkin Institute of Transformative Technologies in Health Care, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, 02138, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Health Care, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA.
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, 02138, USA.
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22
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Abstract
Proteins possess unique molecular recognition capabilities and enzymatic activities, features that are usually tied to a particular tertiary structure. To make use of proteins for biotechnological and biomedical purposes, it is often required to enforce their tertiary structure in order to ensure sufficient stability under the conditions inherent to the application of interest. The introduction of intramolecular crosslinks has proven efficient in stabilizing native protein folds. Herein, we give an overview of methods that allow the macrocyclization of expressed proteins, discussing involved reaction mechanisms and structural implications.
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Affiliation(s)
- Anissa Haim
- Department of Chemistry and Pharmaceutical SciencesVU University AmsterdamAmsterdamThe Netherlands
| | - Saskia Neubacher
- Department of Chemistry and Pharmaceutical SciencesVU University AmsterdamAmsterdamThe Netherlands
- Incircular B.V.De Boelelaan 11081081 HZAmsterdamThe Netherlands
| | - Tom N. Grossmann
- Department of Chemistry and Pharmaceutical SciencesVU University AmsterdamAmsterdamThe Netherlands
- Amsterdam Institute of Molecular and Life SciencesVU University AmsterdamAmsterdamThe Netherlands
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23
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Abstract
The claims that a large fraction of the immunopeptidome is composed of spliced major histocompatibility complex (MHC) peptides have stirred significant excitement and raised controversy. Here, I suggest that there are likely no spliced peptides in the immunopeptidome, and if they exist at all, they are extremely rare. I base this claim on both biochemical and bioinformatics considerations. First, as a reactant in normal proteolytic reactions, water will compete with transpeptidation, which has been suggested as the mechanism of peptide splicing. The high mobility and abundance of water in aqueous solutions renders transpeptidation very inefficient and therefore unlikely to occur. Second, new studies have refuted the bioinformatics assignments to spliced peptides of most of the immunopeptidome MS data, suggesting that the correct assignments are likely other canonical, noncanonical, and post-translationally modified peptides. Therefore, I call for rigorous experimental methodology using heavy stable isotope peptides spiking into the immunoaffinity-purified mixtures of natural MHC peptides and analysis by the highly reliable targeted MS, to claim that MHC peptides are indeed spliced. Peptide splicing was suggested to contribute to the immunopeptidome. I suggest that this idea should be reconsidered based on new evidences. Both biochemical and bioinformatics considerations argue against peptide splicing.
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Affiliation(s)
- Arie Admon
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
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24
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Chen X, Zhang S, Du K, Zheng N, Liu Y, Chen H, Xie G, Ma Y, Zhou Y, Zheng Y, Zeng L, Yang J, Shen L. Gastric cancer-secreted exosomal X26nt increases angiogenesis and vascular permeability by targeting VE-cadherin. Cancer Sci 2021; 112:1839-1852. [PMID: 33205567 PMCID: PMC8088954 DOI: 10.1111/cas.14740] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/12/2020] [Accepted: 11/14/2020] [Indexed: 12/21/2022] Open
Abstract
Angiogenesis is closely associated with tumorigenesis, invasion, and metastasis by providing oxygen and nutrients. Recently, increasing evidence indicates that cancer-derived exosomes which contain proteins, coding, and noncoding RNAs (ncRNAs) were shown to have proangiogenic function in cancer. A 26-nt-long ncRNA (X26nt) is generated in the process of inositol-requiring enzyme 1 alpha (IRE1α)-induced unspliced XBP1 splicing. However, the role of X26nt in the angiogenesis of gastric cancer (GC) remains largely unknown. In the present study, we found that X26nt was significantly elevated in GC and GC exosomes. Then, we verified that X26nt could be delivered into human umbilical vein endothelial cells (HUVECs) via GC cell exosomes and promote the proliferation, migration, and tube formation of HUVECs. We revealed that exosomal X26nt decreased vascular endothelial cadherin (VE-cadherin) by directly combining the 3'UTR of VE-cadherin mRNA in HUVECs, thereby increasing vascular permeability. We further demonstrated that X26nt accelerates the tumor growth and angiogenesis in a mouse subcutaneous tumor model. Our findings investigate a unique intercellular communication mediated by cancer-derived exosomes and reveal a novel mechanism of exosomal X26nt in the regulation of tumor vasculature.
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Affiliation(s)
- Xiaocui Chen
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Shuqiong Zhang
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Kun Du
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Naisheng Zheng
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yi Liu
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Hui Chen
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Guohua Xie
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yanhui Ma
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yunlan Zhou
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yingxia Zheng
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Lingfang Zeng
- School of Cardiovascular Medicine and SciencesKing's College – London British Heart Foundation Centre of ExcellenceFaculty of Life Science and MedicineKing's College LondonLondonUK
| | - Junyao Yang
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Lisong Shen
- Department of Clinical LaboratoryXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Faculty of Medical Laboratory SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
- Xin Hua Children's HospitalShanghaiChina
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25
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Ryu J, Lee E, Kang C, Lee M, Kim S, Park S, Lee D, Kwon Y. Rapid Screening of Glucocorticoid Receptor (GR) Effectors Using Cortisol-Detecting Sensor Cells. Int J Mol Sci 2021; 22:4747. [PMID: 33947115 PMCID: PMC8124850 DOI: 10.3390/ijms22094747] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/22/2021] [Accepted: 04/28/2021] [Indexed: 01/02/2023] Open
Abstract
Cortisol, a stress hormone, plays key roles in mediating stress and anti-inflammatory responses. As abnormal cortisol levels can induce various adverse effects, screening cortisol and cortisol analogues is important for monitoring stress levels and for identifying drug candidates. A novel cell-based sensing system was adopted for rapid screening of cortisol and its functional analogues under complex cellular regulation. We used glucocorticoid receptor (GR) fused to a split intein which reconstituted with the counterpart to trigger conditional protein splicing (CPS) in the presence of targets. CPS generates functional signal peptides which promptly translocate the fluorescent cargo. The sensor cells exhibited exceptional performance in discriminating between the functional and structural analogues of cortisol with improved sensitivity. Essential oil extracts with stress relief activity were screened using the sensor cells to identify GR effectors. The sensor cells responded to peppermint oil, and L-limonene and L-menthol were identified as potential GR effectors from the major components of peppermint oil. Further analysis indicated L-limonene as a selective GR agonist (SEGRA) which is a potential anti-inflammatory agent as it attenuates proinflammatory responses without causing notable adverse effects of GR agonists.
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Affiliation(s)
| | | | | | | | | | | | | | - Youngeun Kwon
- Department of Biomedical Engineering, Dongguk University, Seoul 04620, Korea; (J.R.); (E.L.); (C.K.); (M.L.); (S.K.); (S.P.); (D.L.)
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26
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Mansurkhodzhaev A, Barbosa CRR, Mishto M, Liepe J. Proteasome-Generated cis-Spliced Peptides and Their Potential Role in CD8 + T Cell Tolerance. Front Immunol 2021; 12:614276. [PMID: 33717099 PMCID: PMC7943738 DOI: 10.3389/fimmu.2021.614276] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/28/2021] [Indexed: 01/09/2023] Open
Abstract
The human immune system relies on the capability of CD8+ T cells to patrol body cells, spot infected cells and eliminate them. This cytotoxic response is supposed to be limited to infected cells to avoid killing of healthy cells. To enable this, CD8+ T cells have T Cell Receptors (TCRs) which should discriminate between self and non-self through the recognition of antigenic peptides bound to Human Leukocyte Antigen class I (HLA-I) complexes-i.e., HLA-I immunopeptidomes-of patrolled cells. The majority of these antigenic peptides are produced by proteasomes through either peptide hydrolysis or peptide splicing. Proteasome-generated cis-spliced peptides derive from a given antigen, are immunogenic and frequently presented by HLA-I complexes. Theoretically, they also have a very large sequence variability, which might impinge upon our model of self/non-self discrimination and central and peripheral CD8+ T cell tolerance. Indeed, a large variety of cis-spliced epitopes might enlarge the pool of viral-human zwitter epitopes, i.e., peptides that may be generated with the exact same sequence from both self (human) and non-self (viral) antigens. Antigenic viral-human zwitter peptides may be recognized by CD8+ thymocytes and T cells, induce clonal deletion or other tolerance processes, thereby restraining CD8+ T cell response against viruses. To test this hypothesis, we computed in silico the theoretical frequency of zwitter non-spliced and cis-spliced epitope candidates derived from human proteome (self) and from the proteomes of a large pool of viruses (non-self). We considered their binding affinity to the representative HLA-A*02:01 complex, self-antigen expression in Medullary Thymic Epithelial cells (mTECs) and the relative frequency of non-spliced and cis-spliced peptides in HLA-I immunopeptidomes. Based on the present knowledge of proteasome-catalyzed peptide splicing and neglecting CD8+ TCR degeneracy, our study suggests that, despite their frequency, the portion of the cis-spliced peptides we investigated could only marginally impinge upon the variety of functional CD8+ cytotoxic T cells (CTLs) involved in anti-viral response.
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Affiliation(s)
- Artem Mansurkhodzhaev
- Quantitative and Systems Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
| | - Camila R. R. Barbosa
- Centre for Inflammation Biology and Cancer Immunology (CIBCI) and Peter Gorer Department of Immunobiology, King's College London, London, United Kingdom
| | - Michele Mishto
- Centre for Inflammation Biology and Cancer Immunology (CIBCI) and Peter Gorer Department of Immunobiology, King's College London, London, United Kingdom
- Francis Crick Institute, London, United Kingdom
| | - Juliane Liepe
- Quantitative and Systems Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
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27
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Bhagawati M, Hoffmann S, Höffgen KS, Piehler J, Busch KB, Mootz HD. In Cellulo Protein Semi-Synthesis from Endogenous and Exogenous Fragments Using the Ultra-Fast Split Gp41-1 Intein. Angew Chem Int Ed Engl 2020; 59:21007-21015. [PMID: 32777124 PMCID: PMC7693240 DOI: 10.1002/anie.202006822] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/15/2020] [Indexed: 12/19/2022]
Abstract
Protein semi-synthesis inside live cells from exogenous and endogenous parts offers unique possibilities for studying proteins in their native context. Split-intein-mediated protein trans-splicing is predestined for such endeavors and has seen some successes, but a much larger variety of established split inteins and associated protocols is urgently needed. We characterized the association and splicing parameters of the Gp41-1 split intein, which favorably revealed a nanomolar affinity between the intein fragments combined with the exceptionally fast splicing rate. Following bead-loading of a chemically modified intein fragment precursor into live mammalian cells, we fluorescently labeled target proteins on their N- and C-termini with short peptide tags, thus ensuring minimal perturbation of their structure and function. In combination with a nuclear-entrapment strategy to minimize cytosolic fluorescence background, we applied our technique for super-resolution imaging and single-particle tracking of the outer mitochondrial protein Tom20 in HeLa cells.
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Affiliation(s)
- Maniraj Bhagawati
- Department of Chemistry and PharmacyInstitute of Biochemistry, University of MünsterCorrensstrasse 3648149MünsterGermany
| | - Simon Hoffmann
- Department of Chemistry and PharmacyInstitute of Biochemistry, University of MünsterCorrensstrasse 3648149MünsterGermany
| | - Katharina S. Höffgen
- Department of Chemistry and PharmacyInstitute of Biochemistry, University of MünsterCorrensstrasse 3648149MünsterGermany
| | - Jacob Piehler
- Department of Biology and Center for Cellular NanoanalyticsUniversity of OsnabrückBarbarastrasse 1149076OsnabrückGermany
| | - Karin B. Busch
- Institute of Molecular Cell BiologyUniversity of MünsterSchlossplatz 548149MünsterGermany
| | - Henning D. Mootz
- Department of Chemistry and PharmacyInstitute of Biochemistry, University of MünsterCorrensstrasse 3648149MünsterGermany
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28
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Khoo KK, Galleano I, Gasparri F, Wieneke R, Harms H, Poulsen MH, Chua HC, Wulf M, Tampé R, Pless SA. Chemical modification of proteins by insertion of synthetic peptides using tandem protein trans-splicing. Nat Commun 2020; 11:2284. [PMID: 32385250 PMCID: PMC7210297 DOI: 10.1038/s41467-020-16208-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/20/2020] [Indexed: 12/20/2022] Open
Abstract
Manipulation of proteins by chemical modification is a powerful way to decipher their function. However, most ribosome-dependent and semi-synthetic methods have limitations in the number and type of modifications that can be introduced, especially in live cells. Here, we present an approach to incorporate single or multiple post-translational modifications or non-canonical amino acids into proteins expressed in eukaryotic cells. We insert synthetic peptides into GFP, NaV1.5 and P2X2 receptors via tandem protein trans-splicing using two orthogonal split intein pairs and validate our approach by investigating protein function. We anticipate the approach will overcome some drawbacks of existing protein enigineering methods.
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Affiliation(s)
- K K Khoo
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - I Galleano
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - F Gasparri
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - R Wieneke
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue Strasse 9, 60438, Frankfurt/Main, Germany
| | - H Harms
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - M H Poulsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - H C Chua
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - M Wulf
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - R Tampé
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue Strasse 9, 60438, Frankfurt/Main, Germany
| | - S A Pless
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark.
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29
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Abstract
Inteins are protein segments capable of joining adjacent residues via a peptide bond. In this process known as protein splicing, the intein itself is not present in the final sequence, thus achieving scarless peptide ligation. Here, we assess the splicing activity of 34 inteins (both uncharacterized and known) using a rapid split fluorescent reporter characterization platform, and establish a library of 15 mutually orthogonal split inteins for in vivo applications, 10 of which can be simultaneously used in vitro. We show that orthogonal split inteins can be coupled to multiple split transcription factors to implement complex logic circuits in living organisms, and that they can also be used for the in vitro seamless assembly of large repetitive proteins with biotechnological relevance. Our work demonstrates the versatility and vast potential of an expanded library of orthogonal split inteins for their use in the fields of synthetic biology and protein engineering.
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Affiliation(s)
- Filipe Pinto
- School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Ella Lucille Thornton
- School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Baojun Wang
- School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FF, UK.
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3FF, UK.
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30
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Abstract
Protein semisynthesis is a powerful tool for studying proteins and has contributed to a better understanding of protein structure and function and also driven innovations in protein science. Expressed protein ligation (EPL) is a widely used method to generate chemically modified proteins. However, EPL has some limitations, particularly relevant to modify challenging proteins such as antibodies. The method termed streamlined expressed protein ligation (SEPL) overcomes some of the problems of EPL, and other methods of protein semisynthesis, to generate challenging modified proteins such as antibody-drug conjugates (ADCs). ADCs targeting highly cytotoxic molecules to cancer cells, offer an attractive strategy to selectively eliminate tumor cells with improved therapeutic index than the antibodies or cytotoxic molecules themselves. Despite the potential of ADCs, the development of such complex molecules is challenging. We provide here protocols to prepare site-specifically modified ADCs by streamlined expressed protein ligation (SEPL), which does not require the incorporation of unnatural modifications into the antibody. Therefore, fully native antibodies, with only the desired cytotoxic molecules attached, can be generated.
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31
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Abstract
Expressed protein ligation is a method of protein semisynthesis and typically involves the reaction of recombinant protein C-terminal thioesters with N-cysteine containing synthetic peptides in a chemoselective ligation. The recombinant protein C-terminal thioesters are produced by exploiting the action of nature's inteins which are protein modules that catalyze protein splicing. This chapter discusses the basic principles of expressed protein ligation and recent advances and applications in this protein semisynthesis field. Comparative strengths and weaknesses of the method and future challenges are highlighted.
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Affiliation(s)
- Zhipeng A Wang
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.
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32
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Abstract
Expressed protein ligation is a simple and powerful method in protein engineering to introduce sequences of unnatural amino acids, posttranslational modifications, and biophysical probes into proteins of any size. This methodology has been developed based on the knowledge obtained from protein splicing. Protein splicing is a multistep biochemical reaction that includes the concomitant cleavage and formation of peptide bonds carried out by self-processing domains named inteins. The natural substrates of protein splicing are essential proteins found in intein-containing organisms; inteins are also functional in nonnative frameworks and can be used to alter nearly any protein's primary amino acid sequence. Accordingly, different reactivity features of inteins have been largely exploited to manipulate proteins in countless methods encompassing fields from biochemical research to the development of biotechnological applications including the study of disease progression and validation of potential drug candidates. Here, we review almost three decades of research to uncover the chemical and biochemical enigmas of protein splicing and the development of inteins as potent protein engineering tools.
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Affiliation(s)
- Alejandro Romero-Casañas
- Laboratori d'Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Girona, Spain
| | - Verónica Gordo
- Laboratori d'Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Girona, Spain
| | - Jessica Castro
- Laboratori d'Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Girona, Spain
| | - Marc Ribó
- Laboratori d'Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Girona, Spain.
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33
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Liepe J, Sidney J, Lorenz FKM, Sette A, Mishto M. Mapping the MHC Class I-Spliced Immunopeptidome of Cancer Cells. Cancer Immunol Res 2019; 7:62-76. [PMID: 30425108 DOI: 10.1158/2326-6066.cir-18-0424] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/12/2018] [Accepted: 11/08/2018] [Indexed: 11/16/2022]
Abstract
Anticancer immunotherapies demand optimal epitope targets, which could include proteasome-generated spliced peptides if tumor cells were to present them. Here, we show that spliced peptides are widely presented by MHC class I molecules of colon and breast carcinoma cell lines. The peptides derive from hot spots within antigens and enlarge the antigen coverage. Spliced peptides also represent a large number of antigens that would otherwise be neglected by patrolling T cells. These antigens tend to be long, hydrophobic, and basic. Thus, spliced peptides can be a key to identifying targets in an enlarged pool of antigens associated with cancer.
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Affiliation(s)
- Juliane Liepe
- Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
| | - John Sidney
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Felix K M Lorenz
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Alessandro Sette
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Michele Mishto
- Centre for Inflammation Biology and Cancer Immunology (CIBCI) and Peter Gorer Department of Immunobiology, King's College London, London, United Kingdom.
- Charité- Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institut für Biochemie, Berlin, Germany
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34
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Abstract
We report the development of soluble expression phage-assisted continuous evolution (SE-PACE), a system for rapidly evolving proteins with increased soluble expression. Through use of a PACE-compatible AND gate that uses a split-intein pIII, SE-PACE enables two simultaneous positive selections to evolve proteins with improved expression while maintaining their desired activities. In as little as three days, SE-PACE evolved several antibody fragments with >5-fold improvement in expression yield while retaining binding activity. We also developed an activity-independent form of SE-PACE to correct folding-defective variants of maltose-binding protein (MBP) and to evolve variants of the eukaryotic cytidine deaminase APOBEC1 with improved expression properties. These evolved APOBEC1 variants were found to improve the expression and apparent activity of Cas9-derived base editors when used in place of the wild-type cytidine deaminase. Together, these results suggest that SE-PACE can be applied to a wide variety of proteins to rapidly improve their soluble expression.
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Affiliation(s)
- Tina Wang
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Ahmed H Badran
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Tony P Huang
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA, USA.
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
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35
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Abstract
Split inteins associate to trigger protein splicing in trans, a post-translational modification in which protein sequences fused to the intein pair are ligated together in a traceless manner. Recently, a family of naturally split inteins has been identified that is split at a noncanonical location in the primary sequence. These atypically split inteins show considerable promise in protein engineering applications; however, the mechanism by which they associate is unclear and must be different from that of previously characterized canonically split inteins due to unique topological restrictions. Here, we use a consensus design strategy to generate an atypical split intein pair (Cat) that has greatly improved activity and is amenable to detailed biochemical and biophysical analysis. Guided by the solution structure of Cat, we show that the association of the fragments involves a disorder-to-order structural transition driven by hydrophobic interactions. This molecular recognition mechanism satisfies the topological constraints of the intein fold and, importantly, ensures that premature chemistry does not occur prior to fragment complementation. Our data lead a common blueprint for split intein complementation in which localized structural rearrangements are used to drive folding and regulate protein-splicing activity.
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Affiliation(s)
- Adam J. Stevens
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, United States
| | - Giridhar Sekar
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Josef A. Gramespacher
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, United States
| | - David Cowburn
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Tom W. Muir
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, United States
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36
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Jeon H, Lee E, Kim D, Lee M, Ryu J, Kang C, Kim S, Kwon Y. Cell-Based Biosensors Based on Intein-Mediated Protein Engineering for Detection of Biologically Active Signaling Molecules. Anal Chem 2018; 90:9779-9786. [PMID: 30028129 DOI: 10.1021/acs.analchem.8b01481] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Live-cell-based biosensors have emerged as a useful tool for biotechnology and chemical biology. Genetically encoded sensor cells often use bimolecular fluorescence complementation or fluorescence resonance energy transfer to build a reporter unit that suffers from nonspecific signal activation at high concentrations. Here, we designed genetically encoded sensor cells that can report the presence of biologically active molecules via fluorescence-translocation based on split intein-mediated conditional protein trans-splicing (PTS) and conditional protein trans-cleavage (PTC) reactions. In this work, the target molecules or the external stimuli activated intein-mediated reactions, which resulted in activation of the fluorophore-conjugated signal peptide. This approach fully valued the bond-making and bond-breaking features of intein-mediated reactions in sensor construction and thus eliminated the interference of false-positive signals resulting from the mere binding of fragmented reporters. We could also avoid the necessity of designing split reporters to refold into active structures upon reconstitution. These live-cell-based sensors were able to detect biologically active signaling molecules, such as Ca2+ and cortisol, as well as relevant biological stimuli, such as histamine-induced Ca2+ stimuli and the glucocorticoid receptor agonist, dexamethasone. These live-cell-based sensing systems hold large potential for applications such as drug screening and toxicology studies, which require functional information about targets.
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Affiliation(s)
- Hyunjin Jeon
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Euiyeon Lee
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Dahee Kim
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Minhyung Lee
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Jeahee Ryu
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Chungwon Kang
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Soyoun Kim
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
| | - Youngeun Kwon
- Department of Biomedical Engineering (BK21 plus) , Dongguk University , Seoul 04620 , Korea
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37
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Pirzer T, Becher KS, Rieker M, Meckel T, Mootz HD, Kolmar H. Generation of Potent Anti-HER1/2 Immunotoxins by Protein Ligation Using Split Inteins. ACS Chem Biol 2018; 13:2058-2066. [PMID: 29920062 DOI: 10.1021/acschembio.8b00222] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cell targeting protein toxins have gained increasing interest for cancer therapy aimed at increasing the therapeutic window and reducing systemic toxicity. Because recombinant expression of immunotoxins consisting of a receptor-binding and a cell-killing moiety is hampered by their high toxicity in a eukaryotic production host, most applications rely on recombinant production of fusion proteins consisting of an antibody fragment and a protein toxin in bacterial hosts such as Escherichia coli ( E. coli). These fusions often lack beneficial properties of whole antibodies like extended serum half-life or efficient endocytic uptake via receptor clustering. Here, we describe the production of full-length antibody immunotoxins using self-splicing split inteins. To this end, the short (11 amino acids) N-terminal intein part of the artificially designed split intein M86, a derivative of the Ssp DnaB intein, was recombinantly fused to the heavy chain of trastuzumab, a human epidermal growth factor receptor 2 (HER2) receptor targeting antibody and to a nanobody-Fc fusion targeting the HER1 receptor, respectively. Both antibodies were produced in Expi293F cells. The longer C-terminal counterpart of the intein was genetically fused to the protein toxins gelonin or Pseudomonas Exotoxin A, respectively, and expressed in E. coli via fusion to maltose binding protein. Using optimized in vitro splicing conditions, we were able to generate a set of specific and potent immunotoxins with IC50 values in the mid- to subpicomolar range.
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Affiliation(s)
- Thomas Pirzer
- Institute for Organic Chemistry and Biochemistry , Technische Universität Darmstadt , Alarich-Weiss-Strasse 4 , D-64287 Darmstadt , Germany
| | - Kira-Sophie Becher
- Institute of Biochemistry , University of Münster , Wilhelm-Klemm-Straße 2 , D-48149 Münster , Germany
| | - Marcel Rieker
- Antibody Drug Conjugates and Targeted NBE Therapeutics , Merck KGaA , Frankfurter Straße 250 , D-64293 Darmstadt , Germany
- Protein Engineering and Antibody Technologies , Merck KGaA , Frankfurter Straße 250 , D-64293 Darmstadt , Germany
| | - Tobias Meckel
- Macromolecular Chemistry & Paper Chemistry, Department of Chemistry , Technische Universität Darmstadt , Alarich-Weiss-Straße 8 , D-64287 Darmstadt , Germany
| | - Henning D Mootz
- Institute of Biochemistry , University of Münster , Wilhelm-Klemm-Straße 2 , D-48149 Münster , Germany
| | - Harald Kolmar
- Institute for Organic Chemistry and Biochemistry , Technische Universität Darmstadt , Alarich-Weiss-Strasse 4 , D-64287 Darmstadt , Germany
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38
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Gramespacher JA, Stevens AJ, Thompson RE, Muir TW. Improved protein splicing using embedded split inteins. Protein Sci 2018; 27:614-619. [PMID: 29226478 PMCID: PMC5818749 DOI: 10.1002/pro.3357] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 12/01/2017] [Indexed: 01/24/2023]
Abstract
Naturally split inteins mediate a traceless protein ligation process known as protein trans-splicing (PTS). Although frequently used in protein engineering applications, the efficiency of PTS can be reduced by the tendency of some split intein fusion constructs to aggregate; a consequence of the fragmented nature of the split intein itself or the polypeptide to which it is fused (the extein). Here, we report a strategy to help address this liability. This involves embedding the split intein within a protein sequence designed to stabilize either the intein fragment itself or the appended extein. We expect this approach to increase the scope of PTS-based protein engineering efforts.
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Affiliation(s)
| | - Adam J. Stevens
- Department of ChemistryPrinceton University, Frick Laboratory, PrincetonNew Jersey
| | - Robert E. Thompson
- Department of ChemistryPrinceton University, Frick Laboratory, PrincetonNew Jersey
| | - Tom W. Muir
- Department of ChemistryPrinceton University, Frick Laboratory, PrincetonNew Jersey
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39
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Han Z, Su WW. Intein-mediated assembly of tunable scaffoldins for facile synthesis of designer cellulosomes. Appl Microbiol Biotechnol 2018; 102:1331-1342. [PMID: 29275429 DOI: 10.1007/s00253-017-8701-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 11/05/2017] [Accepted: 12/04/2017] [Indexed: 01/26/2023]
Abstract
In this study, extended artificial scaffoldins possessing multiple cohesin modules were created in vivo by employing split-intein-mediated protein ligation. Artificial scaffoldins having one Clostridium thermocellum cohesin (Coht), one carbohydrate binding module (CBM) from Clostridium cellulolyticum scaffolding protein CipC, and one to five cohesins (Cohc) derived from CipC, were assembled. These scaffoldins were used to assemble cellulosomal enzyme complexes for investigating the interplay among endoglucanase, exoglucanase, and scaffoldin-borne CBM, on the hydrolysis of a model microcrystalline cellulose substrate, Avicel. The cellulosomal complexes were assembled in vitro by incubating recombinant C. thermocellum endoglucanase (At) and C. cellulolyticum exoglucanase (Ec), with the various artificial scaffoldins. Under a fixed total cellulase concentration, improved hydrolysis is noted by recruiting both Ec and At on the same scaffoldin, for all scaffoldins tested, compared with free cellulases. The improvement is more profound with scaffoldins having a higher Cohc/Coht ratio (i.e., increased Ec/At ratio). Furthermore, among scaffoldins having the same Cohc/Coht ratio, highest rates of Avicel hydrolysis are noted when Coht, and hence an endoglucanase, is situated next to the CBM and not flanked by Cohc. These results point to the importance of using scaffoldins with sufficiently high numbers of cohesin units to achieve an optimal exo-/endo-glucanase ratio to create efficient designer cellulosomes. Furthermore, intein-trans-splicing is proven here to be an effective method for assembling complex scaffoldins and more intricate cellulosomes.
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Affiliation(s)
- Zhenlin Han
- Department of Molecular Biosciences and Bioengineering, University of Hawaii, Honolulu, HI, 96822, USA
| | - Wei Wen Su
- Department of Molecular Biosciences and Bioengineering, University of Hawaii, Honolulu, HI, 96822, USA.
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Iwaï H, Mikula KM, Oeemig JS, Zhou D, Li M, Wlodawer A. Structural Basis for the Persistence of Homing Endonucleases in Transcription Factor IIB Inteins. J Mol Biol 2017; 429:3942-3956. [PMID: 29055778 PMCID: PMC6309676 DOI: 10.1016/j.jmb.2017.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/29/2017] [Accepted: 10/12/2017] [Indexed: 11/19/2022]
Abstract
Inteins are mobile genetic elements that are spliced out of proteins after translation. Some inteins contain a homing endonuclease (HEN) responsible for their propagation. Hedgehog/INTein (HINT) domains catalyzing protein splicing and their nested HEN domains are thought to be functionally independent because of the existence of functional mini-inteins without HEN domains. Despite the lack of obvious mutualism between HEN and HINT domains, HEN domains are persistently found at one specific site in inteins, indicating their potential functional role in protein splicing. Here we report crystal structures of inactive and active mini-inteins derived from inteins residing in the transcription factor IIB of Methanococcus jannaschii and Methanocaldococcus vulcanius, revealing a novel modified HINT fold that might provide new insights into the mutualism between the HEN and HINT domains. We propose an evolutionary model of inteins and a functional role of HEN domains in inteins.
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Affiliation(s)
- Hideo Iwaï
- Research Program in Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P.O. Box 65, Helsinki FIN-00014, Finland.
| | - Kornelia M Mikula
- Research Program in Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P.O. Box 65, Helsinki FIN-00014, Finland
| | - Jesper S Oeemig
- Research Program in Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P.O. Box 65, Helsinki FIN-00014, Finland
| | - Dongwen Zhou
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Mi Li
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA; Basic Science Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Alexander Wlodawer
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA.
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Neugebauer M, Böcker JK, Matern JCJ, Pietrokovski S, Mootz HD. Development of a screening system for inteins active in protein splicing based on intein insertion into the LacZα-peptide. Biol Chem 2017; 398:57-67. [PMID: 27632429 DOI: 10.1515/hsz-2016-0229] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/23/2016] [Indexed: 11/15/2022]
Abstract
Protein splicing by inteins has found diverse applications in biotechnology, protein chemistry and chemical biology. Inteins display a wide range of efficiencies and rates unpredictable from their amino acid sequences. Here, we identified positions T22S and S35 in the LacZα peptide as intein insertion sites that strictly require protein splicing, in contrast to cleavage side-reactions, to allow for complementation of β-galactosidase activity. Both the cis-variant of the M86 mutant of the Ssp DnaB intein and a split form undergoing protein trans-splicing gave rise to formation of blue colonies in the β-galactosidase read-out. Furthermore, we report the two novel, naturally split VidaL T4Lh-1 and VidaL UvsX-2 inteins whose N-terminal fragments consist of only 15 and 16 amino acids, respectively. Initial biochemical characterization with the LacZα host system of these inteins further underlines its utility. Finally, we used the LacZα host system to rapidly identify amino acid substitutions from a small randomized library at the structurally conserved intein position 2 next to the catalytic center, that are tolerated for protein splicing activity of the M86 intein. These findings demonstrate the potential of the system for initial testing and directed evolution of inteins.
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Abstract
An emerging body of evidence indicates that post-transcriptional gene regulation relies not only on the sequence of mRNAs but also on their folding into intricate secondary structures and on the chemical modifications of the RNA bases. These features, which are highly dynamic and interdependent, exert direct control over the transcriptome and thereby influence many aspects of cell function. Here, we consider how the coupling of RNA modifications and structures shapes RNA-protein interactions at different steps of the gene expression process.
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Affiliation(s)
| | - Tao Pan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60637, USA
| | - Auinash Kalsotra
- Department of Biochemistry, University of Illinois
- Institute of Genomic Biology, University of Illinois, Urbana-Champaign, Illinois 61801, USA
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Abstract
Split inteins have emerged as a powerful tool in protein engineering. We describe a reliable in silico method to predict viable split sites for the design of new split inteins. A computational circular permutation (CP) prediction method facilitates the search for internal permissive sites to create artificial circular permutants. In this procedure, the original amino- and carboxyl-termini are connected and new termini are created. The identified new terminal sites are promising candidates for the generation of new split sites with the backbone opening being tolerated by the structural scaffold. Here we show how to integrate the online usage of the CP predictor, CPred, in the search of new split intein sites.
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Affiliation(s)
- Yi-Zong Lee
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, 30013, Hsinchu, Taiwan
| | - Wei-Cheng Lo
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.
- Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
| | - Shih-Che Sue
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, 30013, Hsinchu, Taiwan.
- Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan.
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Sonntag T. A Cassette Approach for the Identification of Intein Insertion Sites. Methods Mol Biol 2017; 1495:239-258. [PMID: 27714621 DOI: 10.1007/978-1-4939-6451-2_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Over the past decade split inteins have established themselves as powerful tools for protein engineering, protein semisynthesis, and protein functional control approaches. Their key advantage lies in the protein trans-splicing (PTS) reaction that enables posttranslational protein assembly from two independent, even synthetic, peptide precursors. However, since most split intein applications deal with fragmentation and modification of proteins, various issues can arise, ranging from reduced stability to impairment of protein folding. In this chapter I address how the usage of DNA encoded intein cassettes can streamline and speed up the identification of functional split intein insertion sites in novel proteins of interest (POI).
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Affiliation(s)
- Tim Sonntag
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute for Biological Studies, La Jolla, California, 92037, USA.
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Wang S, Chen B, Wang Y, Feng L, Xia H. [Application of inteins in building protein affinity purification system]. Sheng Wu Gong Cheng Xue Bao 2016; 32:1175-1184. [PMID: 29022318 DOI: 10.13345/j.cjb.150543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Intein is a part of polypeptide in the premature protein with the capability of self-splicing, which is widely applied in protein purification, protein conjuction, cyclopeptide preparation, protein labeling and biosensor. In this review, we summarized the development of intein used in protein purification, discussed intein-mediated chromatographic and non-chromatographic purification systems, and summarized the researches in manipulating intein cleavage reaction. This work is to provide clues for improvement of intein-mediated protein purification.
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Affiliation(s)
- Shujing Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Bingyou Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Yujun Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Lili Feng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Haifeng Xia
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
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Liu S, Sehgal SK, Lin M, Li J, Trick HN, Gill BS, Bai G. Independent mis-splicing mutations in TaPHS1 causing loss of preharvest sprouting (PHS) resistance during wheat domestication. New Phytol 2015; 208:928-35. [PMID: 26255630 DOI: 10.1111/nph.13489] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 04/30/2015] [Indexed: 05/19/2023]
Abstract
Preharvest sprouting (PHS) is one of the major constraints of wheat production in areas where prolonged rainfall occurs during harvest. TaPHS1 is a gene that regulates PHS resistance on chromosome 3A of wheat, and two causal mutations in the positions +646 and +666 of the TaPHS1 coding region result in wheat PHS susceptibility. Three competitive allele-specific PCR (KASP) markers were developed based on the two mutations in the coding region and one in the promoter region and validated in 82 wheat cultivars with known genotypes. These markers can be used to transfer TaPHS1 in breeding through marker-assisted selection. Screening of 327 accessions of wheat A genome progenitors using the three KASP markers identified different haplotypes in both diploid and tetraploid wheats. Only one Triticum monococcum accession, however, carries both causal mutations in the TaPHS1 coding region and shows PHS susceptibility. Five of 249 common wheat landraces collected from the Fertile Crescent and surrounding areas carried the mutation (C) in the promoter (-222), and one landrace carries both the causal mutations in the TaPHS1 coding region, indicating that the mis-splicing (+646) mutation occurred during common wheat domestication. PHS assay of wheat progenitor accessions demonstrated that the wild-types were highly PHS-resistant, whereas the domesticated type showed increased PHS susceptibility. The mis-splicing TaPHS1 mutation for PHS susceptibility was involved in wheat domestication and might arise independently between T. monococcum and Triticum aestivum.
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Affiliation(s)
- Shubing Liu
- State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, 271018, China
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Sunish K Sehgal
- Department of Plant Science, South Dakota State University, Brookings, SD, 57006, USA
- Department of Plant Pathology, Kansas State University, Manhattan, KS, 66506, USA
| | - Meng Lin
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Jiarui Li
- Department of Plant Pathology, Kansas State University, Manhattan, KS, 66506, USA
| | - Harold N Trick
- Department of Plant Pathology, Kansas State University, Manhattan, KS, 66506, USA
| | - Bikram S Gill
- Department of Plant Pathology, Kansas State University, Manhattan, KS, 66506, USA
| | - Guihua Bai
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
- Hard Winter Wheat Genetic Research Unit, USDA-ARS, Manhattan, KS, 66506, USA
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Berkers CR, de Jong A, Schuurman KG, Linnemann C, Geenevasen JAJ, Schumacher TNM, Rodenko B, Ovaa H. Peptide Splicing in the Proteasome Creates a Novel Type of Antigen with an Isopeptide Linkage. J Immunol 2015; 195:4075-84. [PMID: 26401000 PMCID: PMC4642838 DOI: 10.4049/jimmunol.1402454] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 06/23/2015] [Indexed: 11/19/2022]
Abstract
The proteasome is able to create spliced Ags, in which two distant parts of a protein are excised and ligated together to form a novel peptide, for presentation by MHC class I molecules. These noncontiguous epitopes are generated via a transpeptidation reaction catalyzed by the proteasomal active sites. Transpeptidation reactions in the proteasome follow explicit rules and occur particularly efficiently when the C-terminal ligation partner contains a lysine or arginine residue at the site of ligation. Lysine contains two amino groups that theoretically may both participate in ligation reactions, implying that potentially not only peptide but also isopeptide linkages could be formed. Using nuclear magnetic resonance spectroscopy, we demonstrate in the present study that the proteasome can use the ε-amino group of an N-terminal lysine residue in transpeptidation reactions to create a novel type of posttranslationally modified epitopes. We show that the overall efficiency of ε ligation is only 10-fold lower as compared with α ligation, suggesting that the proteasome can produce sufficient isopeptide Ag to evoke a T cell response. Additionally, we show that isopeptides are more stable toward further proteasomal processing than are normal peptides, and we demonstrate that isopeptides can bind to HLA-A2.1 and HLA-A3 with high affinity. These properties likely increase the fraction of ε-ligated peptides presented on the cell surface for CD8(+) T cell surveillance. Finally, we show that isopeptide Ags are immunogenic in vivo. We postulate that ε ligation is a genuine posttranslational modification, suggesting that the proteasome can create a novel type of Ag that is likely to play a role in immunity.
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Affiliation(s)
- Celia R Berkers
- Division of Cell Biology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Annemieke de Jong
- Division of Cell Biology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Karianne G Schuurman
- Division of Cell Biology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Carsten Linnemann
- Division of Immunology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands; and
| | - Jan A J Geenevasen
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, 1098 XH Amsterdam, the Netherlands
| | - Ton N M Schumacher
- Division of Immunology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands; and
| | - Boris Rodenko
- Division of Cell Biology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands;
| | - Huib Ovaa
- Division of Cell Biology, Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands;
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Abstract
Protein splicing is mediated by inteins that auto-catalytically join two separated protein fragments with a peptide bond. Here we engineered a genetically encoded synthetic photoactivatable intein (named LOVInC), by using the light-sensitive LOV2 domain from Avena sativa as a switch to modulate the splicing activity of the split DnaE intein from Nostoc punctiforme. Periodic blue light illumination of LOVInC induced protein splicing activity in mammalian cells. To demonstrate the broad applicability of LOVInC, synthetic protein systems were engineered for the light-induced reassembly of several target proteins such as fluorescent protein markers, a dominant positive mutant of RhoA, caspase-7, and the genetically encoded Ca2+ indicator GCaMP2. Spatial precision of LOVInC was demonstrated by targeting activity to specific mammalian cells. Thus, LOVInC can serve as a general platform for engineering light-based control for modulating the activity of many different proteins.
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Affiliation(s)
- Stanley Wong
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario, M5S 3G9, Canada
| | - Abdullah A. Mosabbir
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario, M5S 3G9, Canada
| | - Kevin Truong
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario, M5S 3G9, Canada
- Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King’s College Circle, Toronto, Ontario, M5S 3G4, Canada
- * E-mail:
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Abstract
INTRODUCTION Metastatic prostate cancer is an incurable disease that is treated with a variety of hormonal therapies targeting various nodes of the androgen receptor (AR) pathway. Invariably patients develop resistance and become castration resistant. Common treatments for castration-resistant disease include novel hormonal therapies, such as abiraterone and enzalutamide, chemotherapy, immunotherapy and radiopharmaceuticals. As this disease generally remains incurable, understanding the molecular underpinnings of resistance pathways is critical in designing therapeutic strategies to delay or overcome such resistance. AREAS COVERED This review will explore the resistance mechanisms relevant to hormonal agents, such as AR-V7 expression and others, as well as discussing new approaches being developed to treat patients with castration-resistant prostate cancer that take advantage of these new insights. A literature search was performed to identify all published clinical trials related to androgen therapy mechanisms of drug resistance in metastatic castration-resistant prostate cancer. EXPERT OPINION Androgen therapy resistance mechanisms are varied, and include modification of all nodes in the androgen signaling pathway. The optimal treatment for men with relapsed metastatic castration-resistant prostate cancer is uncertain at this time. The authors recommend using available clinical data to guide treatment decision making until more specific biomarkers are clinically available.
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Affiliation(s)
- Benjamin L Maughan
- Medical Oncology Fellow, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, 1650 Orleans St. CRB1 186, Baltimore, MD USA
| | - Emmanuel S Antonarakis
- Assistant Professor of Oncology, Assistant Professor of Urology, Johns Hopkins Sidney Kimmel, Comprehensive, Cancer Center, 1650 Orleans St. CRB1 186, Baltimore, MD, USA, Tel: + 410 502 7528; Fax: + 410 614 8397
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Zhang B, Rapolu M, Liang Z, Han Z, Williams PG, Su WW. A dual-intein autoprocessing domain that directs synchronized protein co-expression in both prokaryotes and eukaryotes. Sci Rep 2015; 5:8541. [PMID: 25712612 PMCID: PMC4339811 DOI: 10.1038/srep08541] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 01/23/2015] [Indexed: 12/21/2022] Open
Abstract
Being able to coordinate co-expression of multiple proteins is necessary for a variety of important applications such as assembly of protein complexes, trait stacking, and metabolic engineering. Currently only few options are available for multiple recombinant protein co-expression, and most of them are not applicable to both prokaryotic and eukaryotic hosts. Here, we report a new polyprotein vector system that is based on a pair of self-excising mini-inteins fused in tandem, termed the dual-intein (DI) domain, to achieve synchronized co-expression of multiple proteins. The DI domain comprises an Ssp DnaE mini-intein N159A mutant and an Ssp DnaB mini-intein C1A mutant connected in tandem by a peptide linker to mediate efficient release of the flanking proteins via autocatalytic cleavage. Essentially complete release of constituent proteins, GFP and RFP (mCherry), from a polyprotein precursor, in bacterial, mammalian, and plant hosts was demonstrated. In addition, successful co-expression of GFP with chloramphenicol acetyltransferase, and thioredoxin with RFP, respectively, further substantiates the general applicability of the DI polyprotein system. Collectively, our results demonstrate the DI-based polyprotein technology as a highly valuable addition to the molecular toolbox for multi-protein co-expression which finds vast applications in biotechnology, biosciences, and biomedicine.
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Affiliation(s)
- Bei Zhang
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
| | - Madhusudhan Rapolu
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
| | - Zhibin Liang
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
| | - Zhenlin Han
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
| | - Philip G. Williams
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
| | - Wei Wen Su
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
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