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Tran DT, Juang YC, Tsai L. Contrary response of porcine articular cartilage below and over 1000 s -1. Clin Biomech (Bristol, Avon) 2021; 90:105506. [PMID: 34610506 DOI: 10.1016/j.clinbiomech.2021.105506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/31/2021] [Accepted: 09/27/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Knee joints experience excessive loads quite frequently during sports activities, and these shocks could accelerate progressive degeneration in articular cartilage. METHODS Quasi-static and dynamic response of porcine knee articular cartilages were investigated in this research. Split Hopkinson Pressure Bars (SHPB) were utilized to examine the articular cartilage properties at strain rates between 0.01-2000 s-1. FINDINGS The results showed that strain rate is an important factor for articular cartilages, distinctively divided into above and below 1000 s-1. The articular cartilages exhibit a strain hardening phenomenon when shock loaded at strain rates under 1000 s-1. When loaded at strain rates over 1000 s-1, their ultimate strength and elastic modulus decreased with increasing strain rates. INTERPRETATION The biphasic structure of the cartilage explained the change of modulus. At the lower strain rates, fibers realigned and solidified the structure, while at higher strain rates, there is not enough time for the tissue fluid to move inside the cartilage, leading to a reduction in the deformability of the specimen and raising of Young's modulus. The results can be utilized to provide some useful data for biomaterial and computational works in the future.
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Affiliation(s)
- D T Tran
- National Kaohsiung University of Science and Technology, Department of Mechanical Engineering, No. 415, Jiangong rd., Kaohsiung, Taiwan
| | - Y C Juang
- National Kaohsiung University of Science and Technology, Department of Mechanical Engineering, No. 415, Jiangong rd., Kaohsiung, Taiwan
| | - L Tsai
- National Kaohsiung University of Science and Technology, Department of Mechanical Engineering, No. 415, Jiangong rd., Kaohsiung, Taiwan.
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2
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Lim S, Khoo R, Juang YC, Gopal P, Zhang H, Yeo C, Peh KM, Teo J, Ng S, Henry B, Partridge AW. Exquisitely Specific anti-KRAS Biodegraders Inform on the Cellular Prevalence of Nucleotide-Loaded States. ACS Cent Sci 2021; 7:274-291. [PMID: 33655066 PMCID: PMC7908030 DOI: 10.1021/acscentsci.0c01337] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Indexed: 05/05/2023]
Abstract
Mutations to RAS proteins (H-, N-, and K-RAS) are among the most common oncogenic drivers, and tumors harboring these lesions are some of the most difficult to treat. Although covalent small molecules against KRASG12C have shown promising efficacy against lung cancers, traditional barriers remain for drugging the more prevalent KRASG12D and KRASG12V mutants. Targeted degradation has emerged as an attractive alternative approach, but for KRAS, identification of the required high-affinity ligands continues to be a challenge. Another significant hurdle is the discovery of a hybrid molecule that appends an E3 ligase-recruiting moiety in a manner that satisfies the precise geometries required for productive polyubiquitin transfer while maintaining favorable druglike properties. To gain insights into the advantages and feasibility of KRAS targeted degradation, we applied a protein-based degrader (biodegrader) approach. This workflow centers on the intracellular expression of a chimeric protein consisting of a high-affinity target-binding domain fused to an engineered E3 ligase adapter. A series of anti-RAS biodegraders spanning different RAS isoform/nucleotide-state specificities and leveraging different E3 ligases provided definitive evidence for RAS degradability. Further, these established that the functional consequences of KRAS degradation are context dependent. Of broader significance, using the exquisite degradation specificity that biodegraders can possess, we demonstrated how this technology can be applied to answer questions that other approaches cannot. Specifically, application of the GDP-state specific degrader uncovered the relative prevalence of the "off-state" of WT and various KRAS mutants in the cellular context. Finally, if delivery challenges can be addressed, anti-RAS biodegraders will be exciting candidates for clinical development.
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3
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Ng S, Juang YC, Chandramohan A, Kaan HYK, Sadruddin A, Yuen TY, Ferrer-Gago FJ, Lee XC, Liew X, Johannes CW, Brown CJ, Kannan S, Aronica PG, Berglund NA, Verma CS, Liu L, Stoeck A, Sawyer TK, Partridge AW, Lane DP. De-risking Drug Discovery of Intracellular Targeting Peptides: Screening Strategies to Eliminate False-Positive Hits. ACS Med Chem Lett 2020; 11:1993-2001. [PMID: 33062184 DOI: 10.1021/acsmedchemlett.0c00022] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/01/2020] [Indexed: 12/14/2022] Open
Abstract
Nonspecific promiscuous compounds can mislead researchers and waste significant resources. This phenomenon, though well-documented for small molecules, has not been widely explored for the peptide modality. Here we demonstrate that two purported peptide-based KRas inhibitors, SAH-SOS1 A and cyclorasin 9A5, exemplify false-positive molecules-in terms of both their binding affinities and cellular activities. Through multiple gold-standard biophysical techniques, we unambiguously show that both peptides lack specific binding to KRas and instead induce protein unfolding. Although these peptides inhibited cellular proliferation, the activities appeared to be off-target on the basis of a counterscreen with KRas-independent cell lines. We further demonstrate that their cellular activities are derived from membrane disruption. Accordingly, we propose that to de-risk false-positive molecules, orthogonal binding assays and cellular counterscreens are indispensable.
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Affiliation(s)
| | | | | | | | | | - Tsz Ying Yuen
- Institute of Chemical and Engineering Sciences, A*STAR, Singapore 138665
| | | | - Xue’Er Cheryl Lee
- Institute of Chemical and Engineering Sciences, A*STAR, Singapore 138665
| | - Xi Liew
- Institute of Chemical and Engineering Sciences, A*STAR, Singapore 138665
| | | | | | | | | | | | | | - Lijuan Liu
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | | | - Tomi K. Sawyer
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
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4
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Taylor CA, Cormier KW, Keenan SE, Earnest S, Stippec S, Wichaidit C, Juang YC, Wang J, Shvartsman SY, Goldsmith EJ, Cobb MH. Functional divergence caused by mutations in an energetic hotspot in ERK2. Proc Natl Acad Sci U S A 2019; 116:15514-15523. [PMID: 31296562 PMCID: PMC6681740 DOI: 10.1073/pnas.1905015116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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: 11/18/2022] Open
Abstract
The most frequent extracellular signal-regulated kinase 2 (ERK2) mutation occurring in cancers is E322K (E-K). ERK2 E-K reverses a buried charge in the ERK2 common docking (CD) site, a region that binds activators, inhibitors, and substrates. Little is known about the cellular consequences associated with this mutation, other than apparent increases in tumor resistance to pathway inhibitors. ERK2 E-K, like the mutation of the preceding aspartate (ERK2 D321N [D-N]) known as the sevenmaker mutation, causes increased activity in cells and evades inactivation by dual-specificity phosphatases. As opposed to findings in cancer cells, in developmental assays in Drosophila, only ERK2 D-N displays a significant gain of function, revealing mutation-specific phenotypes. The crystal structure of ERK2 D-N is indistinguishable from that of wild-type protein, yet this mutant displays increased thermal stability. In contrast, the crystal structure of ERK2 E-K reveals profound structural changes, including disorder in the CD site and exposure of the activation loop phosphorylation sites, which likely account for the decreased thermal stability of the protein. These contiguous mutations in the CD site of ERK2 are both required for docking interactions but lead to unpredictably different functional outcomes. Our results suggest that the CD site is in an energetically strained configuration, and this helps drive conformational changes at distal sites on ERK2 during docking interactions.
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Affiliation(s)
- Clinton A Taylor
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Kevin W Cormier
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Shannon E Keenan
- Department of Chemical and Biological Engineering, Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Svetlana Earnest
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Steve Stippec
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Chonlarat Wichaidit
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Yu-Chi Juang
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Junmei Wang
- Department of Biophysics, UT Southwestern Medical Center, Dallas, TX 75390
| | - Stanislav Y Shvartsman
- Department of Chemical and Biological Engineering, Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | | | - Melanie H Cobb
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390;
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5
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Partridge AW, Kaan HYK, Juang YC, Sadruddin A, Lim S, Brown CJ, Ng S, Thean D, Ferrer F, Johannes C, Yuen TY, Kannan S, Aronica P, Tan YS, Pradhan MR, Verma CS, Hochman J, Chen S, Wan H, Ha S, Sherborne B, Lane DP, Sawyer TK. Incorporation of Putative Helix-Breaking Amino Acids in the Design of Novel Stapled Peptides: Exploring Biophysical and Cellular Permeability Properties. Molecules 2019; 24:E2292. [PMID: 31226791 PMCID: PMC6632053 DOI: 10.3390/molecules24122292] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [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: 05/22/2019] [Revised: 06/14/2019] [Accepted: 06/16/2019] [Indexed: 12/21/2022] Open
Abstract
Stapled α-helical peptides represent an emerging superclass of macrocyclic molecules with drug-like properties, including high-affinity target binding, protease resistance, and membrane permeability. As a model system for probing the chemical space available for optimizing these properties, we focused on dual Mdm2/MdmX antagonist stapled peptides related to the p53 N-terminus. Specifically, we first generated a library of ATSP-7041 (Chang et al., 2013) analogs iteratively modified by L-Ala and D-amino acids. Single L-Ala substitutions beyond the Mdm2/(X) binding interfacial residues (i.e., Phe3, Trp7, and Cba10) had minimal effects on target binding, α-helical content, and cellular activity. Similar binding affinities and cellular activities were noted at non-interfacial positions when the template residues were substituted with their d-amino acid counterparts, despite the fact that d-amino acid residues typically 'break' right-handed α-helices. d-amino acid substitutions at the interfacial residues Phe3 and Cba10 resulted in the expected decreases in binding affinity and cellular activity. Surprisingly, substitution at the remaining interfacial position with its d-amino acid equivalent (i.e., Trp7 to d-Trp7) was fully tolerated, both in terms of its binding affinity and cellular activity. An X-ray structure of the d-Trp7-modified peptide was determined and revealed that the indole side chain was able to interact optimally with its Mdm2 binding site by a slight global re-orientation of the stapled peptide. To further investigate the comparative effects of d-amino acid substitutions we used linear analogs of ATSP-7041, where we replaced the stapling amino acids by Aib (i.e., R84 to Aib4 and S511 to Aib11) to retain the helix-inducing properties of α-methylation. The resultant analog sequence Ac-Leu-Thr-Phe-Aib-Glu-Tyr-Trp-Gln-Leu-Cba-Aib-Ser-Ala-Ala-NH2 exhibited high-affinity target binding (Mdm2 Kd = 43 nM) and significant α-helicity in circular dichroism studies. Relative to this linear ATSP-7041 analog, several d-amino acid substitutions at Mdm2(X) non-binding residues (e.g., d-Glu5, d-Gln8, and d-Leu9) demonstrated decreased binding and α-helicity. Importantly, circular dichroism (CD) spectroscopy showed that although helicity was indeed disrupted by d-amino acids in linear versions of our template sequence, stapled molecules tolerated these residues well. Further studies on stapled peptides incorporating N-methylated amino acids, l-Pro, or Gly substitutions showed that despite some positional dependence, these helix-breaking residues were also generally tolerated in terms of secondary structure, binding affinity, and cellular activity. Overall, macrocyclization by hydrocarbon stapling appears to overcome the destabilization of α-helicity by helix breaking residues and, in the specific case of d-Trp7-modification, a highly potent ATSP-7041 analog (Mdm2 Kd = 30 nM; cellular EC50 = 600 nM) was identified. Our findings provide incentive for future studies to expand the chemical diversity of macrocyclic α-helical peptides (e.g., d-amino acid modifications) to explore their biophysical properties and cellular permeability. Indeed, using the library of 50 peptides generated in this study, a good correlation between cellular permeability and lipophilicity was observed.
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Affiliation(s)
- Anthony W Partridge
- MSD International, 8 Biomedical Grove, #04-01/05 Neuros Building, Singapore 138665, Singapore.
| | - Hung Yi Kristal Kaan
- MSD International, 8 Biomedical Grove, #04-01/05 Neuros Building, Singapore 138665, Singapore.
| | - Yu-Chi Juang
- MSD International, 8 Biomedical Grove, #04-01/05 Neuros Building, Singapore 138665, Singapore.
| | - Ahmad Sadruddin
- MSD International, 8 Biomedical Grove, #04-01/05 Neuros Building, Singapore 138665, Singapore.
| | - Shuhui Lim
- MSD International, 8 Biomedical Grove, #04-01/05 Neuros Building, Singapore 138665, Singapore.
| | - Christopher J Brown
- p53Lab, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore 138648, Singapore.
| | - Simon Ng
- p53Lab, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore 138648, Singapore.
| | - Dawn Thean
- p53Lab, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore 138648, Singapore.
| | - Fernando Ferrer
- p53Lab, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore 138648, Singapore.
| | - Charles Johannes
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A*STAR), 8 Biomedical Grove, #07, Neuros Building, Singapore 138665, Singapore.
| | - Tsz Ying Yuen
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A*STAR), 8 Biomedical Grove, #07, Neuros Building, Singapore 138665, Singapore.
| | - Srinivasaraghavan Kannan
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
| | - Pietro Aronica
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
| | - Yaw Sing Tan
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
| | - Mohan R Pradhan
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
| | - Chandra S Verma
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
| | | | | | - Hui Wan
- Merck & Co., Inc., Kenilworth, NJ 07033, USA.
| | - Sookhee Ha
- Merck & Co., Inc., Kenilworth, NJ 07033, USA.
| | | | - David P Lane
- p53Lab, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore 138648, Singapore.
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6
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Xiong S, Lorenzen K, Couzens AL, Templeton CM, Rajendran D, Mao DYL, Juang YC, Chiovitti D, Kurinov I, Guettler S, Gingras AC, Sicheri F. Structural Basis for Auto-Inhibition of the NDR1 Kinase Domain by an Atypically Long Activation Segment. Structure 2018; 26:1101-1115.e6. [PMID: 29983373 PMCID: PMC6087429 DOI: 10.1016/j.str.2018.05.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [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: 12/19/2017] [Revised: 02/28/2018] [Accepted: 05/17/2018] [Indexed: 11/27/2022]
Abstract
The human NDR family kinases control diverse aspects of cell growth, and are regulated through phosphorylation and association with scaffolds such as MOB1. Here, we report the crystal structure of the human NDR1 kinase domain in its non-phosphorylated state, revealing a fully resolved atypically long activation segment that blocks substrate binding and stabilizes a non-productive position of helix αC. Consistent with an auto-inhibitory function, mutations within the activation segment of NDR1 dramatically enhance in vitro kinase activity. Interestingly, NDR1 catalytic activity is further potentiated by MOB1 binding, suggesting that regulation through modulation of the activation segment and by MOB1 binding are mechanistically distinct. Lastly, deleting the auto-inhibitory activation segment of NDR1 causes a marked increase in the association with upstream Hippo pathway components and the Furry scaffold. These findings provide a point of departure for future efforts to explore the cellular functions and the mechanism of NDR1.
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MESH Headings
- Adaptor Proteins, Signal Transducing/chemistry
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Amino Acid Sequence
- Binding Sites
- Cell Cycle Proteins
- Cell Line, Tumor
- Cloning, Molecular
- Crystallography, X-Ray
- Epithelial Cells/cytology
- Epithelial Cells/enzymology
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Gene Expression Regulation
- Genetic Vectors/chemistry
- Genetic Vectors/metabolism
- HEK293 Cells
- Hepatocyte Growth Factor/chemistry
- Hepatocyte Growth Factor/genetics
- Hepatocyte Growth Factor/metabolism
- Humans
- Kinetics
- Microtubule-Associated Proteins/chemistry
- Microtubule-Associated Proteins/genetics
- Microtubule-Associated Proteins/metabolism
- Models, Molecular
- Mutation
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- Protein Serine-Threonine Kinases/chemistry
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Proto-Oncogene Proteins/chemistry
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Alignment
- Sequence Homology, Amino Acid
- Serine-Threonine Kinase 3
- Signal Transduction
- Substrate Specificity
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Affiliation(s)
- Shawn Xiong
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Kristina Lorenzen
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Amber L Couzens
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Catherine M Templeton
- Divisions of Structural Biology and Cancer Biology, The Institute of Cancer Research (ICR), London SW7 3RP, UK
| | - Dushyandi Rajendran
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Daniel Y L Mao
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Yu-Chi Juang
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - David Chiovitti
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Igor Kurinov
- Cornell University, Department of Chemistry and Chemical Biology, NE-CAT, Advanced Photon Source, Bldg. 436E, 9700 S. Cass Avenue, Argonne, IL 60439, USA
| | - Sebastian Guettler
- Divisions of Structural Biology and Cancer Biology, The Institute of Cancer Research (ICR), London SW7 3RP, UK.
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
| | - Frank Sicheri
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
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7
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Juang YC, Fradera X, Han Y, Partridge AW. Repurposing a Histamine Detection Platform for High-Throughput Screening of Histidine Decarboxylase. SLAS Discov 2018; 23:974-981. [PMID: 29884090 DOI: 10.1177/2472555218778053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Histidine decarboxylase (HDC) is the primary enzyme that catalyzes the conversion of histidine to histamine. HDC contributes to many physiological responses as histamine plays important roles in allergic reaction, neurological response, gastric acid secretion, and cell proliferation and differentiation. Small-molecule modulation of HDC represents a potential therapeutic strategy for a range of histamine-associated diseases, including inflammatory disease, neurological disorders, gastric ulcers, and select cancers. High-throughput screening (HTS) methods for measuring HDC activity are currently limited. Here, we report the development of a time-resolved fluorescence resonance energy transfer (TR-FRET) assay for monitoring HDC activity. The assay is based on competition between HDC-generated histamine and fluorophore-labeled histamine for binding to a Europium cryptate (EuK)-labeled anti-histamine antibody. We demonstrated that the assay is highly sensitive and simple to develop. Assay validation experiments were performed using low-volume 384-well plates and resulted in good statistical parameters. A pilot HTS screen gave a Z' score > 0.5 and a hit rate of 1.1%, and led to the identification of a validated hit series. Overall, the presented assay should facilitate the discovery of therapeutic HDC inhibitors by acting as a novel tool suitable for large-scale HTS and subsequent interrogation of compound structure-activity relationships.
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Affiliation(s)
- Yu-Chi Juang
- 1 Early Discovery Pharmacology, Translational Medicine Research Centre, MRL, MSD, Singapore
| | - Xavier Fradera
- 2 Discovery Chemistry, Merck Research Laboratories, Merck & Co., Boston, MA, USA
| | - Yongxin Han
- 2 Discovery Chemistry, Merck Research Laboratories, Merck & Co., Boston, MA, USA
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8
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Sawyer TK, Partridge AW, Kaan HYK, Juang YC, Lim S, Johannes C, Yuen TY, Verma C, Kannan S, Aronica P, Tan YS, Sherborne B, Ha S, Hochman J, Chen S, Surdi L, Peier A, Sauvagnat B, Dandliker PJ, Brown CJ, Ng S, Ferrer F, Lane DP. Macrocyclic α helical peptide therapeutic modality: A perspective of learnings and challenges. Bioorg Med Chem 2018; 26:2807-2815. [PMID: 29598901 DOI: 10.1016/j.bmc.2018.03.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 03/03/2018] [Accepted: 03/06/2018] [Indexed: 12/20/2022]
Abstract
Macrocyclic α-helical peptides have emerged as a compelling new therapeutic modality to tackle targets confined to the intracellular compartment. Within the scope of hydrocarbon-stapling there has been significant progress to date, including the first stapled α-helical peptide to enter into clinical trials. The principal design concept of stapled α-helical peptides is to mimic a cognate (protein) ligand relative to binding its target via an α-helical interface. However, it was the proclivity of such stapled α-helical peptides to exhibit cell permeability and proteolytic stability that underscored their promise as unique macrocyclic peptide drugs for intracellular targets. This perspective highlights key learnings as well as challenges in basic research with respect to structure-based design, innovative chemistry, cell permeability and proteolytic stability that are essential to fulfill the promise of stapled α-helical peptide drug development.
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9
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Canny MD, Moatti N, Wan LCK, Fradet-Turcotte A, Krasner D, Mateos-Gomez PA, Zimmermann M, Orthwein A, Juang YC, Zhang W, Noordermeer SM, Seclen E, Wilson MD, Vorobyov A, Munro M, Ernst A, Ng TF, Cho T, Cannon PM, Sidhu SS, Sicheri F, Durocher D. Inhibition of 53BP1 favors homology-dependent DNA repair and increases CRISPR-Cas9 genome-editing efficiency. Nat Biotechnol 2017; 36:95-102. [PMID: 29176614 PMCID: PMC5762392 DOI: 10.1038/nbt.4021] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 10/20/2017] [Indexed: 02/06/2023]
Abstract
Programmable nucleases, such as Cas9, are used for precise genome editing by homology-dependent repair (HDR)1–3. However, HDR efficiency is constrained by competition from other double-strand break (DSB) repair pathways, including non-homologous end-joining (NHEJ)4. We report the discovery of a genetically encoded inhibitor of 53BP1 that increases the efficiency of HDR-dependent genome editing in human and mouse cells. 53BP1 is a key regulator of DSB repair pathway choice in eukaryotic cells4, 5 and functions to favor NHEJ over HDR by suppressing end resection, which is the rate-limiting step in the initiation of HDR. We screened an existing combinatorial library of engineered ubiquitin variants6 for inhibitors of 53BP1. Expression of one variant, named i53 (inhibitor of 53BP1), in human and mouse cells blocked accumulation of 53BP1 at sites of DNA damage and improved gene targeting and chromosomal gene conversion with either double-stranded DNA or single-stranded oligonucleotide donors by up to 5.6-fold. Inhibition of 53BP1 is a robust method to increase efficiency of HDR-based precise genome editing.
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Affiliation(s)
- Marella D Canny
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Nathalie Moatti
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Leo C K Wan
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Amélie Fradet-Turcotte
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Danielle Krasner
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Pedro A Mateos-Gomez
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU Langone Medical Center, New York, New York, USA
| | - Michal Zimmermann
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Alexandre Orthwein
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Yu-Chi Juang
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Wei Zhang
- The Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada
| | - Sylvie M Noordermeer
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Eduardo Seclen
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Marcus D Wilson
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Andrew Vorobyov
- The Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada
| | - Meagan Munro
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Andreas Ernst
- The Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada
| | - Timothy F Ng
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Tiffany Cho
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Paula M Cannon
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Sachdev S Sidhu
- Department of Molecular Genetics, University of Toronto, Ontario, Canada.,The Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada
| | - Frank Sicheri
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Daniel Durocher
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, Canada
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10
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Abstract
The related protein kinases SPAK and OSR1 regulate ion homeostasis in part by phosphorylating cation cotransporter family members. The structure of the kinase domain of OSR1 was determined in the unphosphorylated inactive form and, like some other Ste20 kinases, exhibited a domain-swapped activation loop. To further probe the role of domain swapping in SPAK and OSR1, we have determined the crystal structures of SPAK 63-403 at 3.1 Å and SPAK 63-390 T243D at 2.5 Å resolution. These structures encompass the kinase domain and different portions of the C-terminal tail, the longer without and the shorter with an activating T243D point mutation. The structure of the T243D protein reveals significant conformational differences relative to unphosphorylated SPAK and OSR1 but also has some features of an inactive kinase. Both structures are domain-swapped dimers. Sequences involved in domain swapping were identified and mutated to create a SPAK monomeric mutant with kinase activity, indicating that monomeric forms are active. The monomeric mutant is activated by WNK1 but has reduced activity toward its substrate NKCC2, suggesting regulatory roles for domain swapping. The structure of partially active SPAK T243D is consistent with a multistage activation process in which phosphorylation induces a SPAK conformation that requires further remodeling to build the active structure.
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Affiliation(s)
- Clinton A. Taylor
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Yu-Chi Juang
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Svetlana Earnest
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Samarpita Sengupta
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Elizabeth J. Goldsmith
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Melanie H. Cobb
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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11
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Huang H, Zeqiraj E, Dong B, Jha BK, Duffy NM, Orlicky S, Thevakumaran N, Talukdar M, Pillon MC, Ceccarelli DF, Wan LCK, Juang YC, Mao DYL, Gaughan C, Brinton MA, Perelygin AA, Kourinov I, Guarné A, Silverman RH, Sicheri F. Dimeric structure of pseudokinase RNase L bound to 2-5A reveals a basis for interferon-induced antiviral activity. Mol Cell 2014; 53:221-34. [PMID: 24462203 PMCID: PMC3974923 DOI: 10.1016/j.molcel.2013.12.025] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/21/2013] [Accepted: 12/19/2013] [Indexed: 02/01/2023]
Abstract
RNase L is an ankyrin repeat domain-containing dual endoribonuclease-pseudokinase that is activated by unusual 2,′5′-oligoadenylate (2-5A) second messengers and which impedes viral infections in higher vertebrates. Despite its importance in interferon-regulated antiviral innate immunity, relatively little is known about its precise mechanism of action. Here we present a functional characterization of 2.5 Å and 3.25 Å X-ray crystal and small-angle X-ray scattering structures of RNase L bound to a natural 2-5A activator with and without ADP or the nonhydrolysable ATP mimetic AMP-PNP. These studies reveal how recognition of 2-5A through interactions with the ankyrin repeat domain and the pseudokinase domain, together with nucleotide binding, imposes a rigid intertwined dimer configuration that is essential for RNase catalytic and antiviral functions. The involvement of the pseudokinase domain of RNase L in 2-5A sensing, nucleotide binding, dimerization, and ribonuclease functions highlights the evolutionary adaptability of the eukaryotic protein kinase fold. Structural basis for RNase L regulation by 2-5A and nucleotide (ADP or ATP) binding Recognition of 2-5A is mediated by both ankyrin repeat and protein kinase domains Nucleotide enforces a closed conformation of the kinase domain Nucleotide binding to the pseudokinase domain is essential for RNA cleavage function
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Affiliation(s)
- Hao Huang
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Elton Zeqiraj
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Beihua Dong
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Babal Kant Jha
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Nicole M Duffy
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Stephen Orlicky
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Neroshan Thevakumaran
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Manisha Talukdar
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Monica C Pillon
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Derek F Ceccarelli
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Leo C K Wan
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Yu-Chi Juang
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Daniel Y L Mao
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3, Canada
| | - Christina Gaughan
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Margo A Brinton
- Department of Biology, Georgia State University, Atlanta, GA 30302, USA
| | | | - Igor Kourinov
- NE-CAT APS, Building 436E, Argonne National Lab, Argonne, IL 60439, USA
| | - Alba Guarné
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Robert H Silverman
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| | - Frank Sicheri
- Program in Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
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12
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Ernst A, Avvakumov G, Tong J, Fan Y, Zhao Y, Alberts P, Persaud A, Walker JR, Neculai AM, Neculai D, Vorobyov A, Garg P, Beatty L, Chan PK, Juang YC, Landry MC, Yeh C, Zeqiraj E, Karamboulas K, Allali-Hassani A, Vedadi M, Tyers M, Moffat J, Sicheri F, Pelletier L, Durocher D, Raught B, Rotin D, Yang J, Moran MF, Dhe-Paganon S, Sidhu SS. A strategy for modulation of enzymes in the ubiquitin system. Science 2013; 339:590-5. [PMID: 23287719 PMCID: PMC3815447 DOI: 10.1126/science.1230161] [Citation(s) in RCA: 224] [Impact Index Per Article: 20.4] [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] [Indexed: 12/18/2022]
Abstract
The ubiquitin system regulates virtually all aspects of cellular function. We report a method to target the myriad enzymes that govern ubiquitination of protein substrates. We used massively diverse combinatorial libraries of ubiquitin variants to develop inhibitors of four deubiquitinases (DUBs) and analyzed the DUB-inhibitor complexes with crystallography. We extended the selection strategy to the ubiquitin conjugating (E2) and ubiquitin ligase (E3) enzymes and found that ubiquitin variants can also enhance enzyme activity. Last, we showed that ubiquitin variants can bind selectively to ubiquitin-binding domains. Ubiquitin variants exhibit selective function in cells and thus enable orthogonal modulation of specific enzymatic steps in the ubiquitin system.
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Affiliation(s)
- Andreas Ernst
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - George Avvakumov
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Jiefei Tong
- Hospital for Sick Children, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Yihui Fan
- Texas Children’s Cancer Center, Department of Pediatrics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yanling Zhao
- Texas Children’s Cancer Center, Department of Pediatrics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Philipp Alberts
- Hospital for Sick Children, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Avinash Persaud
- Hospital for Sick Children, 101 College Street, Toronto, Ontario M5G 1L7, Canada
- Biochemistry Department, University of Toronto, Toronto, OntarioM5S 3E1, Canada
| | - John R Walker
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Ana-Mirela Neculai
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Dante Neculai
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Andrew Vorobyov
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Pankaj Garg
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Linda Beatty
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Pak-Kei Chan
- Institut de Recherche en Immunologie et Cancérologie, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Yu-Chi Juang
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Marie-Claude Landry
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Christina Yeh
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Elton Zeqiraj
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Konstantina Karamboulas
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Abdellah Allali-Hassani
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Masoud Vedadi
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Mike Tyers
- Institut de Recherche en Immunologie et Cancérologie, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Jason Moffat
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Ontario Cancer Institute and McLaughlin Centre for Molecular Medicine, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Frank Sicheri
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Laurence Pelletier
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Daniel Durocher
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Brian Raught
- Ontario Cancer Institute and McLaughlin Centre for Molecular Medicine, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Daniela Rotin
- Hospital for Sick Children, 101 College Street, Toronto, Ontario M5G 1L7, Canada
- Biochemistry Department, University of Toronto, Toronto, OntarioM5S 3E1, Canada
| | - Jianhua Yang
- Texas Children’s Cancer Center, Department of Pediatrics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Michael F Moran
- Hospital for Sick Children, 101 College Street, Toronto, Ontario M5G 1L7, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Sirano Dhe-Paganon
- Structural Genomics Consortium, MaRS Centre, 101 College Street, Suite 700, Toronto, Ontario M5G 1L7, Canada
- Department of Physiology, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Sachdev S Sidhu
- Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Department of Molecular Genetics, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Ontario Cancer Institute and McLaughlin Centre for Molecular Medicine, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
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13
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Juang YC, Landry MC, Sanches M, Vittal V, Leung CCY, Ceccarelli DF, Mateo ARF, Pruneda JN, Mao DYL, Szilard RK, Orlicky S, Munro M, Brzovic PS, Klevit RE, Sicheri F, Durocher D. OTUB1 co-opts Lys48-linked ubiquitin recognition to suppress E2 enzyme function. Mol Cell 2012; 45:384-97. [PMID: 22325355 DOI: 10.1016/j.molcel.2012.01.011] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 01/19/2012] [Accepted: 01/20/2012] [Indexed: 12/16/2022]
Abstract
Ubiquitylation entails the concerted action of E1, E2, and E3 enzymes. We recently reported that OTUB1, a deubiquitylase, inhibits the DNA damage response independently of its isopeptidase activity. OTUB1 does so by blocking ubiquitin transfer by UBC13, the cognate E2 enzyme for RNF168. OTUB1 also inhibits E2s of the UBE2D and UBE2E families. Here we elucidate the structural mechanism by which OTUB1 binds E2s to inhibit ubiquitin transfer. OTUB1 recognizes ubiquitin-charged E2s through contacts with both donor ubiquitin and the E2 enzyme. Surprisingly, free ubiquitin associates with the canonical distal ubiquitin-binding site on OTUB1 to promote formation of the inhibited E2 complex. Lys48 of donor ubiquitin lies near the OTUB1 catalytic site and the C terminus of free ubiquitin, a configuration that mimics the products of Lys48-linked ubiquitin chain cleavage. OTUB1 therefore co-opts Lys48-linked ubiquitin chain recognition to suppress ubiquitin conjugation and the DNA damage response.
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Affiliation(s)
- Yu-Chi Juang
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
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14
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Nakada S, Tai I, Panier S, Al-Hakim A, Iemura SI, Juang YC, O'Donnell L, Kumakubo A, Munro M, Sicheri F, Gingras AC, Natsume T, Suda T, Durocher D. Non-canonical inhibition of DNA damage-dependent ubiquitination by OTUB1. Nature 2010; 466:941-6. [PMID: 20725033 DOI: 10.1038/nature09297] [Citation(s) in RCA: 278] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 06/21/2010] [Indexed: 12/14/2022]
Abstract
DNA double-strand breaks (DSBs) pose a potent threat to genome integrity. These lesions also contribute to the efficacy of radiotherapy and many cancer chemotherapeutics. DSBs elicit a signalling cascade that modifies the chromatin surrounding the break, first by ATM-dependent phosphorylation and then by RNF8-, RNF168- and BRCA1-dependent regulatory ubiquitination. Here we report that OTUB1, a deubiquitinating enzyme, is an inhibitor of DSB-induced chromatin ubiquitination. Surprisingly, we found that OTUB1 suppresses RNF168-dependent poly-ubiquitination independently of its catalytic activity. OTUB1 does so by binding to and inhibiting UBC13 (also known as UBE2N), the cognate E2 enzyme for RNF168. This unusual mode of regulation is unlikely to be limited to UBC13 because analysis of OTUB1-associated proteins revealed that OTUB1 binds to E2s of the UBE2D and UBE2E subfamilies. Finally, OTUB1 depletion mitigates the DSB repair defect associated with defective ATM signalling, indicating that pharmacological targeting of the OTUB1-UBC13 interaction might enhance the DNA damage response.
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Affiliation(s)
- Shinichiro Nakada
- Center of Integrated Medical Research, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo, 160-8582, Japan.
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15
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Heise CJ, Xu BE, Deaton SL, Cha SK, Cheng CJ, Earnest S, Sengupta S, Juang YC, Stippec S, Xu Y, Zhao Y, Huang CL, Cobb MH. Serum and glucocorticoid-induced kinase (SGK) 1 and the epithelial sodium channel are regulated by multiple with no lysine (WNK) family members. J Biol Chem 2010; 285:25161-7. [PMID: 20525693 DOI: 10.1074/jbc.m110.103432] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The four WNK (with no lysine (K)) protein kinases affect ion balance and contain an unusual protein kinase domain due to the unique placement of the active site lysine. Mutations in two WNKs cause a heritable form of ion imbalance culminating in hypertension. WNK1 activates the serum- and glucocorticoid-induced protein kinase SGK1; the mechanism is noncatalytic. SGK1 increases membrane expression of the epithelial sodium channel (ENaC) and sodium reabsorption via phosphorylation and sequestering of the E3 ubiquitin ligase neural precursor cell expressed, developmentally down-regulated 4-2 (Nedd4-2), which otherwise promotes ENaC endocytosis. Questions remain about the intrinsic abilities of WNK family members to regulate this pathway. We find that expression of the N termini of all four WNKs results in modest to strong activation of SGK1. In reconstitution experiments in the same cell line all four WNKs also increase sodium current blocked by the ENaC inhibitor amiloride. The N termini of the WNKs also have the capacity to interact with SGK1. More detailed analysis of activation by WNK4 suggests mechanisms in common with WNK1. Further evidence for the importance of WNK1 in this process comes from the ability of Nedd4-2 to bind to WNK1 and the finding that endogenous SGK1 has reduced activity if WNK1 is knocked down by small interfering RNA.
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Affiliation(s)
- Charles J Heise
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9041, USA
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16
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Jivan A, Earnest S, Juang YC, Cobb MH. Radial spoke protein 3 is a mammalian protein kinase A-anchoring protein that binds ERK1/2. J Biol Chem 2009; 284:29437-45. [PMID: 19684019 DOI: 10.1074/jbc.m109.048181] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Initially identified in Chlamydomonas, RSP3 (radial spoke protein 3) is 1 of more than 20 identified radial spoke structural components of motile cilia and is required for axonemal sliding and flagellar motility. The mammalian orthologs for this and other radial spoke proteins, however, remain to be characterized. We found mammalian RSP3 to bind to the MAPK ERK2 through a yeast two-hybrid screen designed to identify interacting proteins that have a higher affinity for the phosphorylated, active form of the protein kinase. Consistent with the screening result, the human homolog, RSPH3, interacts with and is a substrate for ERK1/2. Moreover, RSPH3 is a protein kinase A-anchoring protein (AKAP) that scaffolds the cAMP-dependent protein kinase holoenzyme. The binding of RSPH3 to the regulatory subunits of cAMP-dependent protein kinase, RIIalpha and RIIbeta, is regulated by ERK1/2 activity and phosphorylation. Here we describe an ERK1/2-interacting AKAP and suggest a mechanism by which cAMP-dependent protein kinase-AKAP binding can be modulated by the activity of other enzymes.
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Affiliation(s)
- Arif Jivan
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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17
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Chen W, Chen Y, Xu BE, Juang YC, Stippec S, Zhao Y, Cobb MH. Regulation of a third conserved phosphorylation site in SGK1. J Biol Chem 2009; 284:3453-60. [PMID: 19068477 PMCID: PMC2635031 DOI: 10.1074/jbc.m807502200] [Citation(s) in RCA: 24] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 12/08/2008] [Indexed: 12/25/2022] Open
Abstract
SGK1 (serum- and glucocorticoid-induced kinase 1) is a member of the AGC branch of the protein kinase family. Among well described functions of SGK1 is the regulation of epithelial transport through phosphorylation of the ubiquitin protein ligase Nedd4-2 (neuronal precursor cell expressed developmentally down-regulated 4-2). The activation of SGK1 has been widely accepted to be dependent on the phosphorylation of Thr256 in the activation loop and Ser422 in the hydrophobic motif near the C terminus. Here, we report the identification of two additional phosphorylation sites, Ser397 and Ser401. Both are required for maximum SGK1 activity induced by extracellular agents or by coexpression with other protein kinases, with the largest loss of activity from mutation of Ser397. Coexpression with active Akt1 increased the phosphorylation of Ser397 and thereby SGK1 kinase activity. SGK1 activation was further augmented by coexpression with the protein kinase WNK1 (with no lysine kinase 1). These findings reveal further complexity underlying the regulation of SGK1 activity.
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Affiliation(s)
- Wei Chen
- Department of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9041, USA
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18
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Wilsbacher JL, Juang YC, Khokhlatchev AV, Gallagher E, Binns D, Goldsmith EJ, Cobb MH. Characterization of mitogen-activated protein kinase (MAPK) dimers. Biochemistry 2006; 45:13175-82. [PMID: 17073439 DOI: 10.1021/bi061041w] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [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] [Indexed: 11/29/2022]
Abstract
Phosphorylated ERK2 has an increased capacity to form homodimers relative to unphosphorylated ERK2. We have characterized the nature of the ERK2 dimer and have mutated residues in the crystal dimer interface to examine the impact of dimerization on ERK2 activity. Analysis of the mutants by gel filtration indicates that at least five residues must be mutated simultaneously to produce an ERK2 mutant that is predominantly monomeric. Mutants, whether monomers or dimers, have specific protein kinase activities under fixed assay conditions that are roughly equivalent to wild-type ERK2. The ratio of dimers to monomers is increased as the salt concentration increases, consistent with a strong hydrophobic contribution to the energy of dimer formation. ERK2 dimerization also requires divalent cations. Sedimentation analysis indicates that the related c-Jun N-terminal kinase SAPKalphaI/JNK2 also forms dimers, but dimerization displays no dependence on phosphorylation; the unphosphorylated and phosphorylated forms of the kinase behave similarly, with low micromolar dimer dissociation constants.
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Affiliation(s)
- Julie L Wilsbacher
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, Texas 75390-9041, USA
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19
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Anselmo AN, Earnest S, Chen W, Juang YC, Kim SC, Zhao Y, Cobb MH. WNK1 and OSR1 regulate the Na+, K+, 2Cl- cotransporter in HeLa cells. Proc Natl Acad Sci U S A 2006; 103:10883-8. [PMID: 16832045 PMCID: PMC1544143 DOI: 10.1073/pnas.0604607103] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.6] [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] [Indexed: 11/18/2022] Open
Abstract
Oxidative stress-responsive kinase (OSR) 1 and sterile20-related, proline-, alanine-rich kinase (SPAK) are Ste20p-related protein kinases that bind to the sodium, potassium, two chloride cotransporter, NKCC. Here we present evidence that the protein kinase with no lysine [K] (WNK) 1 regulates OSR1, SPAK, and NKCC activities. OSR1 exists in a complex with WNK1 in cells, is activated by recombinant WNK1 in vitro, and is phosphorylated in a WNK1-dependent manner in cells. Depletion of WNK1 from HeLa cells by using small interfering RNA reduces OSR1 kinase activity. In addition, depletion of either WNK1 or OSR1 reduces NKCC activity, indicating that WNK1 and OSR1 are both required for NKCC function. OSR1 and SPAK are likely links between WNK1 and NKCC in a pathway that contributes to volume regulation and blood pressure homeostasis in mammals.
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Affiliation(s)
| | | | - Wei Chen
- Departments of *Pharmacology and
| | | | - Sung Chan Kim
- Departments of *Pharmacology and
- Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Yingming Zhao
- Departments of *Pharmacology and
- Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Melanie H. Cobb
- Departments of *Pharmacology and
- To whom correspondence should be addressed. E-mail:
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20
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Abstract
The mortality rate of WLTB was significantly higher than non-WLTB in 45 of 516 cases of PTB in a 24-month period. There is no known underlying disease predisposing to WLTB. Clinically, the patients were significantly more toxic and had lower serum albumin and hemoglobin levels than non-WLTB patients. They had a lower rate of positive PPD tuberculin skin tests. The chest roentgenograms revealed three patterns: (1) DBS type in 15--all with multiple or diffuse opacities with or without cavitations; (2) DHS type in 20--eight with typical miliary lesions and 12 with atypical miliary patterns; (3) combined focal PTB and DHS type in ten. We found that atypical chest roentgenographic patterns were common in WLTB and frequently led to misdiagnosis. The delayed diagnosis and treatment of this advanced disease resulted in the high mortality. Early, empirical antituberculosis chemotherapy is indicated and life-saving.
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Affiliation(s)
- T C Tsao
- Department of Chest Medicine, Chang Gung Memorial Hospital, Taiwan, Republic of China
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21
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Juang YC, Tsao TC, Chiang YC, Lin JL, Tsai YH. Acute renal failure and severe thrombocytopenia induced by rifampicin: report of a case. J Formos Med Assoc 1992; 91:475-6. [PMID: 1358323] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
We report on a patient who developed life-threatening thrombocytopenia and acute renal failure after the reinstitution of rifampicin therapy for pulmonary tuberculosis. This combined reaction is rarely reported. Supportive treatment and withdrawal of rifampicin led to complete recovery. The increased incidence of drug-resistant tuberculosis and the need for the reintroduction of rifampicin therapy may lead to more such reactions being observed.
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Affiliation(s)
- Y C Juang
- Department of Chest Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan R.O.C
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22
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Juang YC, Chiang YC, Tsao TC, Lan RS, Lee CH, Tsai YH, Wang JW. Mycoplasma pneumoniae pneumonia: clinical analysis of 45 cases. Changgeng Yi Xue Za Zhi 1991; 14:156-62. [PMID: 1933623] [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] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mycoplasma pneumoniae (M. Pneumoniae) is a primarily pathogen of the respiratory tract. The clinical characteristics, laboratory findings, and roentgenographic patterns of 45 patients with serologically proven M. pneumoniae pneumonia admitted to Chang Gung Hospital from 1981 to 1989 have been reviewed. There were 23 males and 22 females. Forty-one (91%) were below 40 years old and 13 patients (29%) were below 5 years old. Fever, cough and chest rales were the most common symptoms and signs. A transient mild elevation of liver enzymes was seen in 33% of the patients, most of whom were below the age of ten (73%). A leukocyte count over 15,000/cu mm was not rare (16%). Roentgenographic features included unilateral infiltration (84%), lower lobe predominance (60%), and either confluent (56%) or patchy (33%) consolidation. Pleural effusion occurred in 24% of the patients. Complete resolution of chest roentgenography took from 8 to 42 days with a mean of 20 days. The response of fever to treatment with erythromycin took from 1 to 6 days with a mean of 3 days. There were no life threatening pulmonic or extrapulmonic complications.
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Affiliation(s)
- Y C Juang
- Department of Chest Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan, R. O. C
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23
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Tsao TC, Juang YC, Chiang YC, Tsai YH, Lan RS, Lee CH. Pneumonia preceding respiratory failure. A rare, easily misleading clinical manifestation in adult Arnold-Chiari malformation. Chest 1991; 99:1294-5. [PMID: 2019201 DOI: 10.1378/chest.99.5.1294] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [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: 12/29/2022] Open
Abstract
A 47-year-old woman was admitted for bilateral lower lobe pneumonia with respiratory distress. Two episodes of respiratory failure developed despite improvement of pneumonia after antibiotic chemotherapy. Loss of consciousness and quadriplegia accompanied the last episode of respiratory failure. Arnold-Chiari malformation type 1 was diagnosed and a suboccipital craniectomy was performed. The neuromuscular and respiratory disorders greatly improved after operation. We believe that ACM 1 should be considered when an adult develops unexpected respiratory failure after improvement of the primary pulmonary condition. This disease is potentially treatable by surgical management, and if it is misdiagnosed, will be fatal.
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Affiliation(s)
- T C Tsao
- Department of Chest Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan, Republic of China
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24
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Lee CH, Juang YC, Hsueh C. Leiomyoma of the bronchus: report of a case successfully treated by Nd-YAG laser via fiberoptic bronchoscope. J Formos Med Assoc 1990; 89:1012-4. [PMID: 1982121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A 42-year-old woman presented with chronic cough and dyspnea. A leiomyoma of the right middle lobe of the bronchus was diagnosed by bronchoscopic biopsy and treated successfully by neodymium-yttrium aluminum garnet laser, via fiberoptic bronchoscope. The presentations of bronchial leiomyoma are mainly due to partial or complete occlusion of the involved bronchus. Symptoms are mainly cough, wheeze, chest pain and fever, as a result of atelectasis, consolidation, collapse or bronchiectasis. The management of this benign tumor of the lung is discussed, and the importance of early diagnosis and conservative therapy are emphasized.
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Affiliation(s)
- C H Lee
- Department of Pulmonary Medicine, Chang Guang Memorial Hospital, Taipei, Taiwan, R.O.C
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25
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Abstract
Respiratory failure (RF) developed in 43 (40.2 percent) of 107 patients with acute organophosphate or carbamate poisoning; 22 (51.2 percent) died. The 64 patients who did not develop RF survived. All cases of RF developed within 96 hours after poisoning: within 24 hours in 35 patients (acute onset) and between 24 and 96 hours in eight patients (subacute onset). Severity of poisoning was the primary determinating factor for RF. Cardiovascular collapse and pneumonia were also associated with RF. In 19 patients with cardiovascular collapse, 17 had acute onset of RF and two had subacute onset. In 28 patients with pneumonia, 17 developed acute onset of RF and eight developed subacute onset. No organophosphorus compound caused RF more frequently than another. The duration of ventilator support for subacute RF was significantly longer than for acute RF (287 +/- 186 vs 115 +/- 103 hours, p = 0.02). The use of pralidoxime did not reduce the incidence of RF. We found that severity of poisoning, cardiovascular collapse, and pneumonia were the predisposing factors to RF. The golden time for treatment of acute organophosphate or carbamate poisoning was the initial 96 hours. No RF occurred after this time. Aggressive treatment and prevention of the above three factors will reduce the incidence of RF, or in other words, reduce the mortality.
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Affiliation(s)
- T C Tsao
- Department of Chest Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan, Republic of China
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26
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Juang YC, Wang LS, Chen CH, Lin CY. Mycobacterium fortuitum mastitis following augmentation mammaplasty: report of a case. Taiwan Yi Xue Hui Za Zhi 1989; 88:278-81. [PMID: 2794927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A 26-year-old woman was admitted to the Veterans General Hospital with the chief problem of recurrent abscess formation over the right breast one month after augmentation mammaplasty. Pus aspirated from the right breast grew Mycobacterium fortuitum, a rapidly growing atypical Mycobacterium, in 4 consecutive cultures. The infected mammanoplastic prosthesis was surgically removed. Acid-fast bacilli were found on pathologic examination of the surgical specimen. Amikacin, doxycycline and ethambutol were given for two weeks according to the sensitivity test. The patient underwent reconstructive surgery of her right breast 10 months later. A specimen obtained from that surgery showed no more acid-fast bacilli on pathological examination. To date there are no signs of recurrence. We suggest that the possibility of mycobacterial infection should be kept in mind when the pus is reported as being "sterile" on an ordinary bacterial culture.
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Abstract
Ludwig's angina remains a potentially lethal disease entity as it causes rapidly progressive airway obstruction, although the current mortality rate is low. Early surgical intervention should be carried out in severe cases which show signs of fluctuation, abscess formation or other serious complications. We report our experience with 14 cases of Ludwig's angina, 12 of which (86%) were of dental origin. Only one case was complicated with Klebsiella pneumoniae septicemia which resolved upon treatment. There were no deaths. Surgical procedures including incision and drainage and tooth extraction were performed in 11 cases (78%). Antibiotics were administered to all patients. Most of them were treated with crystalline penicillin with or without an aminoglycoside. Only one patient received a tracheostomy in this series. The number of tracheostomies or intubations carried out was much lower than in previous reports. We suggest that an aggressive antimicrobial therapy, early surgical intervention and careful monitoring of the respiratory symptoms would reduce both the need for tracheostomy and the mortality rate.
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Affiliation(s)
- Y C Juang
- Department of Medicine, Veterans General Hospital, Taipei, Taiwan, Republic of China
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28
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Fung CP, Wang LS, Juang YC, Liu CY, Cheng DL. Enterobacter cloacae bacteremia: clinical analysis of 41 cases. Zhonghua Yi Xue Za Zhi (Taipei) 1988; 42:297-304. [PMID: 3242768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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29
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Wang FD, Wang LS, Tsai IK, Juang YC, Wong WW, Liu CY. Splenic infarction associated with nonenterococcal endocarditis--report of a case. Zhonghua Yi Xue Za Zhi (Taipei) 1988; 42:219-22. [PMID: 3224323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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30
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Chen CH, Wang CS, Juang YC, Wang LS, Jeng GJ, Lu JY, Perng RP. [Pulmonary cryptococcosis with spontaneous resolution--although with high serum cryptococcal antigen titer]. Zhonghua Yi Xue Za Zhi (Taipei) 1988; 41:379-82. [PMID: 3219650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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