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Jasso GJ, Jaiswal A, Varma M, Laszewski T, Grauel A, Omar A, Silva N, Dranoff G, Porter JA, Mansfield K, Cremasco V, Regev A, Xavier RJ, Graham DB. Colon stroma mediates an inflammation-driven fibroblastic response controlling matrix remodeling and healing. PLoS Biol 2022; 20:e3001532. [PMID: 35085231 PMCID: PMC8824371 DOI: 10.1371/journal.pbio.3001532] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [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: 07/28/2021] [Revised: 02/08/2022] [Accepted: 01/07/2022] [Indexed: 12/22/2022] Open
Abstract
Chronic inflammation is often associated with the development of tissue fibrosis, but how mesenchymal cell responses dictate pathological fibrosis versus resolution and healing remains unclear. Defining stromal heterogeneity and identifying molecular circuits driving extracellular matrix deposition and remodeling stands to illuminate the relationship between inflammation, fibrosis, and healing. We performed single-cell RNA-sequencing of colon-derived stromal cells and identified distinct classes of fibroblasts with gene signatures that are differentially regulated by chronic inflammation, including IL-11-producing inflammatory fibroblasts. We further identify a transcriptional program associated with trans-differentiation of mucosa-associated fibroblasts and define a functional gene signature associated with matrix deposition and remodeling in the inflamed colon. Our analysis supports a critical role for the metalloprotease Adamdec1 at the interface between tissue remodeling and healing during colitis, demonstrating its requirement for colon epithelial integrity. These findings provide mechanistic insight into how inflammation perturbs stromal cell behaviors to drive fibroblastic responses controlling mucosal matrix remodeling and healing.
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Affiliation(s)
- Guadalupe J. Jasso
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alok Jaiswal
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Mukund Varma
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Tyler Laszewski
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Angelo Grauel
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Abdifatah Omar
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Nilsa Silva
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Glenn Dranoff
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Jeffrey A. Porter
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Keith Mansfield
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Viviana Cremasco
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Aviv Regev
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Howard Hughes Medical Institute and David H. Koch Institute for Integrative Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Ramnik J. Xavier
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Klarman Cell Observatory, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail: (RJX); (DBG)
| | - Daniel B. Graham
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail: (RJX); (DBG)
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2
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Ke X, You K, Pichaud M, Haiser HJ, Graham DB, Vlamakis H, Porter JA, Xavier RJ. Gut bacterial metabolites modulate endoplasmic reticulum stress. Genome Biol 2021; 22:292. [PMID: 34654459 PMCID: PMC8518294 DOI: 10.1186/s13059-021-02496-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 09/10/2021] [Indexed: 12/26/2022] Open
Abstract
Background The endoplasmic reticulum (ER) is a membranous organelle that maintains proteostasis and cellular homeostasis, controlling the fine balance between health and disease. Dysregulation of the ER stress response has been implicated in intestinal inflammation associated with inflammatory bowel disease (IBD), a chronic condition characterized by changes to the mucosa and alteration of the gut microbiota. While the microbiota and microbially derived metabolites have also been implicated in ER stress, examples of this connection remain limited to a few observations from pathogenic bacteria. Furthermore, the mechanisms underlying the effects of bacterial metabolites on ER stress signaling have not been well established. Results Utilizing an XBP1s-GFP knock-in reporter colorectal epithelial cell line, we screened 399 microbiome-related metabolites for ER stress pathway modulation. We find both ER stress response inducers (acylated dipeptide aldehydes and bisindole methane derivatives) and suppressors (soraphen A) and characterize their activities on ER stress gene transcription and translation. We further demonstrate that these molecules modulate the ER stress pathway through protease inhibition or lipid metabolism interference. Conclusions Our study identified novel links between classes of gut microbe-derived metabolites and the ER stress response, suggesting the potential for these metabolites to contribute to gut ER homeostasis and providing insight into the molecular mechanisms by which gut microbes impact intestinal epithelial cell homeostasis. Supplementary Information The online version contains supplementary material available at 10.1186/s13059-021-02496-8.
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Affiliation(s)
- Xiaobo Ke
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Novartis Institute for Biomedical Research Inc., Cambridge, MA, 02139, USA
| | - Kwontae You
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Matthieu Pichaud
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Novartis Institute for Biomedical Research Inc., Cambridge, MA, 02139, USA
| | - Henry J Haiser
- Novartis Institute for Biomedical Research Inc., Cambridge, MA, 02139, USA
| | - Daniel B Graham
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Center for Computational and Integrative Biology and Department of Molecular Biology, Massachusetts General Hospital, Harvard School of Medicine, Boston, Massachusetts, 02114, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Jeffrey A Porter
- Novartis Institute for Biomedical Research Inc., Cambridge, MA, 02139, USA
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA. .,Center for Computational and Integrative Biology and Department of Molecular Biology, Massachusetts General Hospital, Harvard School of Medicine, Boston, Massachusetts, 02114, USA. .,Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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3
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Brown EM, Arellano-Santoyo H, Temple ER, Costliow ZA, Pichaud M, Hall AB, Liu K, Durney MA, Gu X, Plichta DR, Clish CA, Porter JA, Vlamakis H, Xavier RJ. Gut microbiome ADP-ribosyltransferases are widespread phage-encoded fitness factors. Cell Host Microbe 2021; 29:1351-1365.e11. [PMID: 34403684 DOI: 10.1016/j.chom.2021.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 06/23/2021] [Accepted: 07/22/2021] [Indexed: 12/13/2022]
Abstract
Bacterial ADP-ribosyltransferases (ADPRTs) have been described as toxins involved in pathogenesis through the modification of host proteins. Here, we report that ADPRTs are not pathogen restricted but widely prevalent in the human gut microbiome and often associated with phage elements. We validated their biochemical activity in a large clinical isolate collection and further examined Bxa, a highly abundant ADPRT in Bacteroides. Bxa is expressed, secreted, and enzymatically active in Bacteroides and can ADP-ribosylate non-muscle myosin II proteins. Addition of Bxa to epithelial cells remodeled the actin cytoskeleton and induced secretion of inosine. Bxa-encoding B. stercoris can use inosine as a carbon source and colonizes the gut to significantly greater numbers than a bxa-deleted strain in germ-free and altered Schaedler flora (ASF) mice. Colonization correlated with increased inosine concentrations in the feces and tissues. Altogether, our results show that ADPRTs are abundant in the microbiome and act as bacterial fitness factors.
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Affiliation(s)
- Eric M Brown
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Hugo Arellano-Santoyo
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Emily R Temple
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Matthieu Pichaud
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - A Brantley Hall
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Kai Liu
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Xiebin Gu
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Clary A Clish
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jeffrey A Porter
- Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ramnik J Xavier
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Klarman Cell Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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4
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Brown EM, Ke X, Hitchcock D, Jeanfavre S, Avila-Pacheco J, Nakata T, Arthur TD, Fornelos N, Heim C, Franzosa EA, Watson N, Huttenhower C, Haiser HJ, Dillow G, Graham DB, Finlay BB, Kostic AD, Porter JA, Vlamakis H, Clish CB, Xavier RJ. Bacteroides-Derived Sphingolipids Are Critical for Maintaining Intestinal Homeostasis and Symbiosis. Cell Host Microbe 2019; 25:668-680.e7. [PMID: 31071294 DOI: 10.1016/j.chom.2019.04.002] [Citation(s) in RCA: 227] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/19/2019] [Accepted: 04/02/2019] [Indexed: 12/28/2022]
Abstract
Sphingolipids are structural membrane components and important eukaryotic signaling molecules. Sphingolipids regulate inflammation and immunity and were recently identified as the most differentially abundant metabolite in stool from inflammatory bowel disease (IBD) patients. Commensal bacteria from the Bacteroidetes phylum also produce sphingolipids, but the impact of these metabolites on host pathways is largely uncharacterized. To determine whether bacterial sphingolipids modulate intestinal health, we colonized germ-free mice with a sphingolipid-deficient Bacteroides thetaiotaomicron strain. A lack of Bacteroides-derived sphingolipids resulted in intestinal inflammation and altered host ceramide pools in mice. Using lipidomic analysis, we described a sphingolipid biosynthesis pathway and revealed a variety of Bacteroides-derived sphingolipids including ceramide phosphoinositol and deoxy-sphingolipids. Annotating Bacteroides sphingolipids in an IBD metabolomic dataset revealed lower abundances in IBD and negative correlations with inflammation and host sphingolipid production. These data highlight the role of bacterial sphingolipids in maintaining homeostasis and symbiosis in the gut.
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Affiliation(s)
- Eric M Brown
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Xiaobo Ke
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Novartis Institute for Biomedical Research Inc., Cambridge, MA 02139, USA
| | | | - Sarah Jeanfavre
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Toru Nakata
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Nadine Fornelos
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Cortney Heim
- Novartis Institute for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Eric A Franzosa
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Nicki Watson
- W. M. Keck Microscopy Facility, The Whitehead Institute, Cambridge, MA 02142, USA
| | - Curtis Huttenhower
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Henry J Haiser
- Novartis Institute for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Glen Dillow
- Novartis Institute for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Daniel B Graham
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - B Brett Finlay
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Aleksandar D Kostic
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; Department of Microbiology and Immunology, Harvard Medical School, Boston, MA 02115, USA
| | - Jeffrey A Porter
- Novartis Institute for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Clary B Clish
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Computational and Integrative Biology and Department of Molecular Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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5
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Franzosa EA, Sirota-Madi A, Avila-Pacheco J, Fornelos N, Haiser HJ, Reinker S, Vatanen T, Hall AB, Mallick H, McIver LJ, Sauk JS, Wilson RG, Stevens BW, Scott JM, Pierce K, Deik AA, Bullock K, Imhann F, Porter JA, Zhernakova A, Fu J, Weersma RK, Wijmenga C, Clish CB, Vlamakis H, Huttenhower C, Xavier RJ. Author Correction: Gut microbiome structure and metabolic activity in inflammatory bowel disease. Nat Microbiol 2019; 4:898. [PMID: 30971771 DOI: 10.1038/s41564-019-0442-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the Supplementary Tables 2, 4 and 6 originally published with this Article, the authors mistakenly included sample identifiers in the form of UMCGs rather than UMCG IBDs in the validation cohort; this has now been amended.
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Affiliation(s)
- Eric A Franzosa
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | | | | | | | - Henry J Haiser
- Novartis Institute for Biomedical Research Inc, Cambridge, MA, USA
| | - Stefan Reinker
- Novartis Institute for Biomedical Research Inc, Cambridge, MA, USA
| | - Tommi Vatanen
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Himel Mallick
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | - Lauren J McIver
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | - Jenny S Sauk
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Robin G Wilson
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Betsy W Stevens
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Kerry Pierce
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Amy A Deik
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Kevin Bullock
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Floris Imhann
- Department of Gastroenterology and Hepatology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands.,Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Jeffrey A Porter
- Novartis Institute for Biomedical Research Inc, Basel, Switzerland
| | - Alexandra Zhernakova
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Jingyuan Fu
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands.,Department of Pediatrics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Rinse K Weersma
- Department of Gastroenterology and Hepatology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Cisca Wijmenga
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands.,Department of Immunology, K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway
| | - Clary B Clish
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Curtis Huttenhower
- Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA.
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. .,Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, USA.
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6
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Franzosa EA, Sirota-Madi A, Avila-Pacheco J, Fornelos N, Haiser HJ, Reinker S, Vatanen T, Hall AB, Mallick H, McIver LJ, Sauk JS, Wilson RG, Stevens BW, Scott JM, Pierce K, Deik AA, Bullock K, Imhann F, Porter JA, Zhernakova A, Fu J, Weersma RK, Wijmenga C, Clish CB, Vlamakis H, Huttenhower C, Xavier RJ. Gut microbiome structure and metabolic activity in inflammatory bowel disease. Nat Microbiol 2019; 4:293-305. [PMID: 30531976 PMCID: PMC6342642 DOI: 10.1038/s41564-018-0306-4] [Citation(s) in RCA: 881] [Impact Index Per Article: 176.2] [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: 11/16/2017] [Accepted: 10/25/2018] [Indexed: 12/13/2022]
Abstract
The inflammatory bowel diseases (IBDs), which include Crohn's disease (CD) and ulcerative colitis (UC), are multifactorial chronic conditions of the gastrointestinal tract. While IBD has been associated with dramatic changes in the gut microbiota, changes in the gut metabolome-the molecular interface between host and microbiota-are less well understood. To address this gap, we performed untargeted metabolomic and shotgun metagenomic profiling of cross-sectional stool samples from discovery (n = 155) and validation (n = 65) cohorts of CD, UC and non-IBD control patients. Metabolomic and metagenomic profiles were broadly correlated with faecal calprotectin levels (a measure of gut inflammation). Across >8,000 measured metabolite features, we identified chemicals and chemical classes that were differentially abundant in IBD, including enrichments for sphingolipids and bile acids, and depletions for triacylglycerols and tetrapyrroles. While > 50% of differentially abundant metabolite features were uncharacterized, many could be assigned putative roles through metabolomic 'guilt by association' (covariation with known metabolites). Differentially abundant species and functions from the metagenomic profiles reflected adaptation to oxidative stress in the IBD gut, and were individually consistent with previous findings. Integrating these data, however, we identified 122 robust associations between differentially abundant species and well-characterized differentially abundant metabolites, indicating possible mechanistic relationships that are perturbed in IBD. Finally, we found that metabolome- and metagenome-based classifiers of IBD status were highly accurate and, like the vast majority of individual trends, generalized well to the independent validation cohort. Our findings thus provide an improved understanding of perturbations of the microbiome-metabolome interface in IBD, including identification of many potential diagnostic and therapeutic targets.
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Affiliation(s)
- Eric A Franzosa
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | | | | | | | - Henry J Haiser
- Novartis Institute for Biomedical Research Inc., Cambridge, MA, USA
| | - Stefan Reinker
- Novartis Institute for Biomedical Research Inc., Cambridge, MA, USA
| | - Tommi Vatanen
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Himel Mallick
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | - Lauren J McIver
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA
| | - Jenny S Sauk
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Robin G Wilson
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Betsy W Stevens
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Kerry Pierce
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Amy A Deik
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Kevin Bullock
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Floris Imhann
- Department of Gastroenterology and Hepatology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Jeffrey A Porter
- Novartis Institute for Biomedical Research Inc., Basel, Switzerland
| | - Alexandra Zhernakova
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Jingyuan Fu
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
- Department of Pediatrics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Rinse K Weersma
- Department of Gastroenterology and Hepatology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Cisca Wijmenga
- Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
- Department of Immunology, K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway
| | - Clary B Clish
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Curtis Huttenhower
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA.
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
- Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, USA.
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7
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Vatanen T, Plichta DR, Somani J, Münch PC, Arthur TD, Hall AB, Rudolf S, Oakeley EJ, Ke X, Young RA, Haiser HJ, Kolde R, Yassour M, Luopajärvi K, Siljander H, Virtanen SM, Ilonen J, Uibo R, Tillmann V, Mokurov S, Dorshakova N, Porter JA, McHardy AC, Lähdesmäki H, Vlamakis H, Huttenhower C, Knip M, Xavier RJ. Genomic variation and strain-specific functional adaptation in the human gut microbiome during early life. Nat Microbiol 2018; 4:470-479. [PMID: 30559407 PMCID: PMC6384140 DOI: 10.1038/s41564-018-0321-5] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [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: 04/18/2018] [Accepted: 11/14/2018] [Indexed: 12/13/2022]
Abstract
The human gut microbiome matures toward the adult composition during the first years of life and is implicated in early immune development. Here, we investigate the effects of microbial genomic diversity on gut microbiome development using integrated early childhood datasets collected in the DIABIMMUNE study in Finland, Estonia and Russian Karelia. We show that gut microbial diversity is associated with household location and linear growth of children. Single nucleotide polymorphism (SNP)- and metagenomic assembly-based strain tracking revealed large and highly dynamic microbial pangenomes, especially in the genus Bacteroides, in which we identified evidence of variability deriving from Bacteroides-targeting bacteriophages. Our analyses revealed functional consequences of strain diversity; only 10% of Finnish infants harbored Bifidobacterium longum subsp. infantis, a subspecies specialized in human milk metabolism, whereas Russian infants commonly maintained a probiotic Bifidobacterium bifidum strain in infancy. Groups of bacteria contributing to diverse, characterized metabolic pathways converged to highly subject-specific configurations over the first two years of life. This longitudinal study extends the current view of early gut microbial community assembly based on strain-level genomic variation.
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Affiliation(s)
- Tommi Vatanen
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Juhi Somani
- Department of Computer Science, Aalto University, Espoo, Finland
| | - Philipp C Münch
- Department for Computational Biology of Infection Research, Helmholtz Center for Infection Research, Brunswick, Germany.,Max von Pettenkofer-Institute for Hygiene and Clinical Microbiology, Ludwig-Maximilian University of Munich, Munich, Germany
| | | | | | - Sabine Rudolf
- Analytical Sciences and Imaging, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Edward J Oakeley
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Xiaobo Ke
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Rachel A Young
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Henry J Haiser
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Raivo Kolde
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Moran Yassour
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Center for Computational and Integrative Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Kristiina Luopajärvi
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.,Research Programs Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland
| | - Heli Siljander
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.,Research Programs Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland.,Department of Pediatrics, Tampere University Hospital, Tampere, Finland
| | - Suvi M Virtanen
- Department of Public Health Solutions, National Institute for Health and Welfare, Helsinki, Finland.,Faculty of Social Sciences/Health Sciences, University of Tampere, Tampere, Finland.,Science Centre, Pirkanmaa Hospital District and Research Center for Child Health, University Hospital, Tampere, Finland
| | - Jorma Ilonen
- Immunogenetics Laboratory, University of Turku, Turku, Finland.,Clinical Microbiology, Turku University Hospital, Turku, Finland
| | - Raivo Uibo
- Department of Immunology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Vallo Tillmann
- Department of Pediatrics, University of Tartu and Tartu University Hospital, Tartu, Estonia
| | - Sergei Mokurov
- Ministry of Health and Social Development, Karelian Republic of the Russian Federation, Petrozavodsk, Russia
| | - Natalya Dorshakova
- Petrozavodsk State University, Department of Family Medicine, Petrozavodsk, Russia
| | - Jeffrey A Porter
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Alice C McHardy
- Department for Computational Biology of Infection Research, Helmholtz Center for Infection Research, Brunswick, Germany
| | - Harri Lähdesmäki
- Department of Computer Science, Aalto University, Espoo, Finland
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Curtis Huttenhower
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Mikael Knip
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.,Research Programs Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland.,Department of Pediatrics, Tampere University Hospital, Tampere, Finland.,Folkhälsan Research Center, Helsinki, Finland
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,Center for Computational and Integrative Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. .,Gastrointestinal Unit, and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. .,Center for Microbiome Informatics and Therapeutics, MIT, Cambridge, MA, USA.
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8
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Wlodarska M, Luo C, Kolde R, d'Hennezel E, Annand JW, Heim CE, Krastel P, Schmitt EK, Omar AS, Creasey EA, Garner AL, Mohammadi S, O'Connell DJ, Abubucker S, Arthur TD, Franzosa EA, Huttenhower C, Murphy LO, Haiser HJ, Vlamakis H, Porter JA, Xavier RJ. Indoleacrylic Acid Produced by Commensal Peptostreptococcus Species Suppresses Inflammation. Cell Host Microbe 2018; 22:25-37.e6. [PMID: 28704649 DOI: 10.1016/j.chom.2017.06.007] [Citation(s) in RCA: 466] [Impact Index Per Article: 77.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 05/12/2017] [Accepted: 06/16/2017] [Indexed: 12/16/2022]
Abstract
Host factors in the intestine help select for bacteria that promote health. Certain commensals can utilize mucins as an energy source, thus promoting their colonization. However, health conditions such as inflammatory bowel disease (IBD) are associated with a reduced mucus layer, potentially leading to dysbiosis associated with this disease. We characterize the capability of commensal species to cleave and transport mucin-associated monosaccharides and identify several Clostridiales members that utilize intestinal mucins. One such mucin utilizer, Peptostreptococcus russellii, reduces susceptibility to epithelial injury in mice. Several Peptostreptococcus species contain a gene cluster enabling production of the tryptophan metabolite indoleacrylic acid (IA), which promotes intestinal epithelial barrier function and mitigates inflammatory responses. Furthermore, metagenomic analysis of human stool samples reveals that the genetic capability of microbes to utilize mucins and metabolize tryptophan is diminished in IBD patients. Our data suggest that stimulating IA production could promote anti-inflammatory responses and have therapeutic benefits.
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Affiliation(s)
- Marta Wlodarska
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Chengwei Luo
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Raivo Kolde
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Eva d'Hennezel
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - John W Annand
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Cortney E Heim
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Philipp Krastel
- Novartis Institutes for BioMedical Research, Novartis Campus, 4056 Basel, Switzerland
| | - Esther K Schmitt
- Novartis Institutes for BioMedical Research, Novartis Campus, 4056 Basel, Switzerland
| | - Abdifatah S Omar
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Elizabeth A Creasey
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Ashley L Garner
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sina Mohammadi
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | | | - Sahar Abubucker
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Timothy D Arthur
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Eric A Franzosa
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Curtis Huttenhower
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Leon O Murphy
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Henry J Haiser
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Hera Vlamakis
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jeffrey A Porter
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Ramnik J Xavier
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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9
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Mavrakis K, McDonald ER, Schlabach MR, Billy E, Hoffman GR, deWeck A, Ruddy DA, Venkatesan K, McAllister G, deBeaumont R, Ho S, Liu Y, Yan-Neale Y, Yang G, Lin F, Yin H, Gao H, Kipp DR, Zhao S, McNamara JT, Sprague ER, Cho YS, Gu J, Crawford K, Capka V, Hurov K, Porter JA, Tallarico J, Mickanin C, Lees E, Pagliarini R, Keen N, Schmelzle T, Hofmann F, Stegmeier F, Sellers WR. Abstract LB-017: Disordered methionine metabolism in MTAP/CDKN2A-deleted cancers leads to marked dependence on PRMT5. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-lb-017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Metabolic genes are increasingly recognized as targets of somatic genetic alteration in human cancer often leading to profound changes in intracellular metabolite concentrations. 5-Methylthioadenosine Phosphorylase (MTAP) is a key enzyme in the methionine salvage pathway that metabolizes methylthioadenosine (MTA) to adenine and methionine. Its chromosomal position proximal to CDKN2A results in frequent collateral homozygous deletion in a wide range of human cancers. By interrogating data from a large scale deep-coverage pooled shRNA screen across 390 cancer cell line models we found that the viability of MTAP null cancer cells is strongly impaired upon shRNA-mediated depletion of the protein arginine methyltransferase PRMT5. In MTAP deleted cells there is marked accumulation of the substrate MTA and surprisingly, we find that MTA is a specific inhibitor of the catalytic activity of PRMT5. In keeping with these data, knockout of MTAP in an MTAP-proficient cell line led to increased MTA levels and rendered them sensitive to PRMT5 depletion. Moreover, reconstitution of MTAP in an MTAP-deficient cell line fully rescued PRMT5 dependence. Collectively, these findings indicate that the collateral loss of MTAP in CDNK2A deleted cancers leads to accumulation of MTA that thereby creates a hypomorphic PRMT5 state that is selectively sensitized towards further PRMT5 inhibition.
Citation Format: Konstantinos Mavrakis, E Robert McDonald III, Michael R. Schlabach, Eric Billy, Gregory R. Hoffman, Antoine deWeck, David A. Ruddy, Kavitha Venkatesan, Greg McAllister, Rosalie deBeaumont, Samuel Ho, Yue Liu, Yan Yan-Neale, Guizhi Yang, Fallon Lin, Hong Yin, Hui Gao, David Randal Kipp, Songping Zhao, Joshua T. McNamara, Elizabeth R. Sprague, Young Shin Cho, Justin Gu, Ken Crawford, Vladimir Capka, Kristen Hurov, Jeffrey A. Porter, John Tallarico, Craig Mickanin, Emma Lees, Raymond Pagliarini, Nicholas Keen, Tobias Schmelzle, Francesco Hofmann, Frank Stegmeier, William R. Sellers. Disordered methionine metabolism in MTAP/CDKN2A-deleted cancers leads to marked dependence on PRMT5. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-017.
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Affiliation(s)
| | | | | | - Eric Billy
- 2Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Antoine deWeck
- 2Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - David A. Ruddy
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | | | | | | | - Samuel Ho
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Yue Liu
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Yan Yan-Neale
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Guizhi Yang
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Fallon Lin
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Hong Yin
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Hui Gao
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | | | - Songping Zhao
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | | | | | - Young Shin Cho
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Justin Gu
- 3China Novartis Institutes for Biomedical Research, Shanghai, China
| | - Ken Crawford
- 4Novartis Institutes for BioMedical Research, Emeryville, CA
| | - Vladimir Capka
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Kristen Hurov
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | | | - John Tallarico
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Craig Mickanin
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Emma Lees
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | | | - Nicholas Keen
- 1Novartis Institutes for BioMedical Research, Cambridge, MA
| | - Tobias Schmelzle
- 2Novartis Institutes for BioMedical Research, Basel, Switzerland
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10
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Vatanen T, Kostic AD, d'Hennezel E, Siljander H, Franzosa EA, Yassour M, Kolde R, Vlamakis H, Arthur TD, Hämäläinen AM, Peet A, Tillmann V, Uibo R, Mokurov S, Dorshakova N, Ilonen J, Virtanen SM, Szabo SJ, Porter JA, Lähdesmäki H, Huttenhower C, Gevers D, Cullen TW, Knip M, Xavier RJ. Variation in Microbiome LPS Immunogenicity Contributes to Autoimmunity in Humans. Cell 2016; 165:842-53. [PMID: 27133167 DOI: 10.1016/j.cell.2016.04.007] [Citation(s) in RCA: 691] [Impact Index Per Article: 86.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 01/19/2016] [Accepted: 03/31/2016] [Indexed: 12/21/2022]
Abstract
According to the hygiene hypothesis, the increasing incidence of autoimmune diseases in western countries may be explained by changes in early microbial exposure, leading to altered immune maturation. We followed gut microbiome development from birth until age three in 222 infants in Northern Europe, where early-onset autoimmune diseases are common in Finland and Estonia but are less prevalent in Russia. We found that Bacteroides species are lowly abundant in Russians but dominate in Finnish and Estonian infants. Therefore, their lipopolysaccharide (LPS) exposures arose primarily from Bacteroides rather than from Escherichia coli, which is a potent innate immune activator. We show that Bacteroides LPS is structurally distinct from E. coli LPS and inhibits innate immune signaling and endotoxin tolerance; furthermore, unlike LPS from E. coli, B. dorei LPS does not decrease incidence of autoimmune diabetes in non-obese diabetic mice. Early colonization by immunologically silencing microbiota may thus preclude aspects of immune education.
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Affiliation(s)
- Tommi Vatanen
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Computer Science, Aalto University School of Science, 02150 Espoo, Finland
| | - Aleksandar D Kostic
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Computational and Integrative Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Eva d'Hennezel
- Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Heli Siljander
- Children's Hospital, University of Helsinki and Helsinki University Hospital, 00290 Helsinki, Finland; Research Programs Unit, Diabetes and Obesity Research Program, University of Helsinki, 00290 Helsinki, Finland; Department of Pediatrics, Tampere University Hospital, 33521 Tampere, Finland
| | - Eric A Franzosa
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Moran Yassour
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Raivo Kolde
- Center for Computational and Integrative Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Hera Vlamakis
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Anu-Maaria Hämäläinen
- Department of Pediatrics, Jorvi Hospital, Helsinki University Hospital, 02740 Espoo, Finland
| | - Aleksandr Peet
- Department of Pediatrics, University of Tartu and Tartu University Hospital, 51014 Tartu, Estonia
| | - Vallo Tillmann
- Department of Pediatrics, University of Tartu and Tartu University Hospital, 51014 Tartu, Estonia
| | - Raivo Uibo
- Department of Immunology, Institute of Biomedicine and Translational Medicine, Centre of Excellence for Translational Medicine, University of Tartu, 50411 Tartu, Estonia
| | - Sergei Mokurov
- Ministry of Health and Social Development, Karelian Republic of the Russian Federation, Lenin Street 6, 185035 Petrozavodsk, Russia
| | - Natalya Dorshakova
- Petrozavodsk State University, Department of Family Medicine, Lenin Street 33, 185910 Petrozavodsk, Russia
| | - Jorma Ilonen
- Immunogenetics Laboratory, University of Turku, 20520 Turku, Finland; Department of Clinical Microbiology, University of Eastern Finland, 70211 Kuopio, Finland
| | - Suvi M Virtanen
- Department of Health, National Institute for Health and Welfare, 00271 Helsinki, Finland; School of Health Sciences, University of Tampere, 33014 Tampere, Finland; Science Centre, Pirkanmaa Hospital District and Research Center for Child Health, University Hospital, 33521 Tampere, Finland
| | - Susanne J Szabo
- Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Jeffrey A Porter
- Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Harri Lähdesmäki
- Department of Computer Science, Aalto University School of Science, 02150 Espoo, Finland
| | - Curtis Huttenhower
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Dirk Gevers
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Thomas W Cullen
- Novartis Institutes for Biomedical Research Inc., Cambridge, MA 02139, USA
| | - Mikael Knip
- Children's Hospital, University of Helsinki and Helsinki University Hospital, 00290 Helsinki, Finland; Research Programs Unit, Diabetes and Obesity Research Program, University of Helsinki, 00290 Helsinki, Finland; Department of Pediatrics, Tampere University Hospital, 33521 Tampere, Finland; Folkhälsan Research Center, 00290 Helsinki, Finland
| | | | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Computational and Integrative Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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11
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Bidinosti M, Botta P, Krüttner S, Proenca CC, Stoehr N, Bernhard M, Fruh I, Mueller M, Bonenfant D, Voshol H, Carbone W, Neal SJ, McTighe SM, Roma G, Dolmetsch RE, Porter JA, Caroni P, Bouwmeester T, Lüthi A, Galimberti I. CLK2 inhibition ameliorates autistic features associated with SHANK3 deficiency. Science 2016; 351:1199-203. [PMID: 26847545 DOI: 10.1126/science.aad5487] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 01/22/2016] [Indexed: 12/17/2022]
Abstract
SH3 and multiple ankyrin repeat domains 3 (SHANK3) haploinsufficiency is causative for the neurological features of Phelan-McDermid syndrome (PMDS), including a high risk of autism spectrum disorder (ASD). We used unbiased, quantitative proteomics to identify changes in the phosphoproteome of Shank3-deficient neurons. Down-regulation of protein kinase B (PKB/Akt)-mammalian target of rapamycin complex 1 (mTORC1) signaling resulted from enhanced phosphorylation and activation of serine/threonine protein phosphatase 2A (PP2A) regulatory subunit, B56β, due to increased steady-state levels of its kinase, Cdc2-like kinase 2 (CLK2). Pharmacological and genetic activation of Akt or inhibition of CLK2 relieved synaptic deficits in Shank3-deficient and PMDS patient-derived neurons. CLK2 inhibition also restored normal sociability in a Shank3-deficient mouse model. Our study thereby provides a novel mechanistic and potentially therapeutic understanding of deregulated signaling downstream of Shank3 deficiency.
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Affiliation(s)
- Michael Bidinosti
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Paolo Botta
- Friedrich Miescher Institute, Basel, Switzerland
| | | | - Catia C Proenca
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Natacha Stoehr
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Mario Bernhard
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Isabelle Fruh
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Matthias Mueller
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Debora Bonenfant
- Analytical Sciences and Imaging, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Hans Voshol
- Analytical Sciences and Imaging, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Walter Carbone
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Sarah J Neal
- Neuroscience, Novartis Institutes for Biomedical Research, Cambridge, USA
| | | | - Guglielmo Roma
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Jeffrey A Porter
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Pico Caroni
- Friedrich Miescher Institute, Basel, Switzerland
| | - Tewis Bouwmeester
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Ivan Galimberti
- Developmental Molecular Pathways, Novartis Institutes for Biomedical Research, Basel, Switzerland.
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12
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Majd B, Majd H, Porter JA, Romberg E, Arola D. Degradation in the fatigue strength of dentin by diamond bur preparations: Importance of cutting direction. J Biomed Mater Res B Appl Biomater 2015; 104:39-49. [PMID: 25611951 DOI: 10.1002/jbm.b.33348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 11/16/2014] [Accepted: 12/02/2014] [Indexed: 11/12/2022]
Abstract
The objectives of this investigation were to evaluate the degradation in fatigue strength of dentin by diamond bur preparations and to identify the importance of cutting direction. Three groups of coronal dentin specimens were prepared from unrestored third molars, including a flaw free "control," and two groups that received a diamond bur cutting treatment performed parallel or perpendicular to the specimen length. The specimens were subjected to static or cyclic flexural loading to failure and the results were compared with data for carbide bur cutting. Under static loading diamond bur cutting resulted in significantly lower flexure strength (p ≤ 0.05) than the control for both cutting directions (from 154 to ∼124 MPa). However, there was no significant difference in the strength between the control and carbide bur treated specimens. Similarly, the fatigue strength of the diamond bur treated specimens was significantly lower (p ≤ 0.0001) than that of the control for both cutting directions. Cutting in the perpendicular direction resulted in nearly 60% reduction to the endurance limit (from 44 to 19 MPa). Based on the results, diamond bur cutting of cavity preparations causes a reduction in the fatigue strength of dentin, regardless of the cutting direction. To maintain the durability of dentin, cavity preparations introduced using diamond burs must be performed with appropriate cutting direction and followed by a finishing pass.
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Affiliation(s)
- B Majd
- Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland
| | - H Majd
- Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland
| | - J A Porter
- Department of Endodontics, Prosthodontics and Operative Dentistry, Dental School, University of Maryland, Baltimore, Maryland
| | - E Romberg
- Department of Endodontics, Prosthodontics and Operative Dentistry, Dental School, University of Maryland, Baltimore, Maryland
| | - D Arola
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington.,Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, Washington
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13
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Cai X, Xu Y, Cheung AK, Tomlinson RC, Alcázar-Román A, Murphy L, Billich A, Zhang B, Feng Y, Klumpp M, Rondeau JM, Fazal AN, Wilson CJ, Myer V, Joberty G, Bouwmeester T, Labow MA, Finan PM, Porter JA, Ploegh HL, Baird D, De Camilli P, Tallarico JA, Huang Q. PIKfyve, a class III PI kinase, is the target of the small molecular IL-12/IL-23 inhibitor apilimod and a player in Toll-like receptor signaling. ACTA ACUST UNITED AC 2014; 20:912-21. [PMID: 23890009 DOI: 10.1016/j.chembiol.2013.05.010] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 05/16/2013] [Accepted: 05/29/2013] [Indexed: 12/15/2022]
Abstract
Toll-like receptor (TLR) signaling is a key component of innate immunity. Aberrant TLR activation leads to immune disorders via dysregulation of cytokine production, such as IL-12/IL-23. Herein, we identify and characterize PIKfyve, a lipid kinase, as a critical player in TLR signaling using apilimod as an affinity tool. Apilimod is a potent small molecular inhibitor of IL-12/IL-23 with an unknown target and has been evaluated in clinical trials for patients with Crohn's disease or rheumatoid arthritis. Using a chemical genetic approach, we show that it binds to PIKfyve and blocks its phosphotransferase activity, leading to selective inhibition of IL-12/IL-23p40. Pharmacological or genetic inactivation of PIKfyve is necessary and sufficient for suppression of IL-12/IL-23p40 expression. Thus, we have uncovered a phosphoinositide-mediated regulatory mechanism that controls TLR signaling.
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Affiliation(s)
- Xinming Cai
- Novartis Institutes for Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA
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14
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Hoepfner D, Helliwell SB, Sadlish H, Schuierer S, Filipuzzi I, Brachat S, Bhullar B, Plikat U, Abraham Y, Altorfer M, Aust T, Baeriswyl L, Cerino R, Chang L, Estoppey D, Eichenberger J, Frederiksen M, Hartmann N, Hohendahl A, Knapp B, Krastel P, Melin N, Nigsch F, Oakeley EJ, Petitjean V, Petersen F, Riedl R, Schmitt EK, Staedtler F, Studer C, Tallarico JA, Wetzel S, Fishman MC, Porter JA, Movva NR. High-resolution chemical dissection of a model eukaryote reveals targets, pathways and gene functions. Microbiol Res 2014; 169:107-20. [DOI: 10.1016/j.micres.2013.11.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 11/25/2013] [Accepted: 11/25/2013] [Indexed: 01/03/2023]
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15
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Xie Y, Zamponi R, Charlat O, Ramones M, Swalley S, Jiang X, Rivera D, Tschantz W, Lu B, Quinn L, Dimitri C, Parker J, Jeffery D, Wilcox SK, Watrobka M, LeMotte P, Granda B, Porter JA, Myer VE, Loew A, Cong F. Interaction with both ZNRF3 and LGR4 is required for the signalling activity of R-spondin. EMBO Rep 2013; 14:1120-6. [PMID: 24165923 DOI: 10.1038/embor.2013.167] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 10/01/2013] [Accepted: 10/01/2013] [Indexed: 02/07/2023] Open
Abstract
R-spondin proteins sensitize cells to Wnt signalling and act as potent stem cell growth factors. Various membrane proteins have been proposed as potential receptors of R-spondin, including LGR4/5, membrane E3 ubiquitin ligases ZNRF3/RNF43 and several others proteins. Here, we show that R-spondin interacts with ZNRF3/RNF43 and LGR4 through distinct motifs. Both LGR4 and ZNRF3 binding motifs are required for R-spondin-induced LGR4/ZNRF3 interaction, membrane clearance of ZNRF3 and activation of Wnt signalling. Importantly, Wnt-inhibitory activity of ZNRF3, but not of a ZNRF3 mutant with reduced affinity to R-spondin, can be strongly suppressed by R-spondin, suggesting that R-spondin primarily functions by binding and inhibiting ZNRF3. Together, our results support a dual receptor model of R-spondin action, where LGR4/5 serve as the engagement receptor whereas ZNRF3/RNF43 function as the effector receptor.
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Affiliation(s)
- Yang Xie
- Novartis Institutes for Biomedical Research, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
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Hoepfner D, McNamara CW, Lim CS, Studer C, Riedl R, Aust T, McCormack SL, Plouffe DM, Meister S, Schuierer S, Plikat U, Hartmann N, Staedtler F, Cotesta S, Schmitt EK, Petersen F, Supek F, Glynne RJ, Tallarico JA, Porter JA, Fishman MC, Bodenreider C, Diagana TT, Movva NR, Winzeler EA. Selective and specific inhibition of the plasmodium falciparum lysyl-tRNA synthetase by the fungal secondary metabolite cladosporin. Cell Host Microbe 2012; 11:654-63. [PMID: 22704625 PMCID: PMC3391680 DOI: 10.1016/j.chom.2012.04.015] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [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: 03/09/2012] [Revised: 04/02/2012] [Accepted: 04/22/2012] [Indexed: 01/06/2023]
Abstract
With renewed calls for malaria eradication, next-generation antimalarials need be active against drug-resistant parasites and efficacious against both liver- and blood-stage infections. We screened a natural product library to identify inhibitors of Plasmodium falciparum blood- and liver-stage proliferation. Cladosporin, a fungal secondary metabolite whose target and mechanism of action are not known for any species, was identified as having potent, nanomolar, antiparasitic activity against both blood and liver stages. Using postgenomic methods, including a yeast deletion strains collection, we show that cladosporin specifically inhibits protein synthesis by directly targeting P. falciparum cytosolic lysyl-tRNA synthetase. Further, cladosporin is >100-fold more potent against parasite lysyl-tRNA synthetase relative to the human enzyme, which is conferred by the identity of two amino acids within the enzyme active site. Our data indicate that lysyl-tRNA synthetase is an attractive, druggable, antimalarial target that can be selectively inhibited.
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Affiliation(s)
- Dominic Hoepfner
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, Forum 1 Novartis Campus, Basel, Switzerland.
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Harbinski F, Craig VJ, Sanghavi S, Jeffery D, Liu L, Sheppard KA, Wagner S, Stamm C, Buness A, Chatenay-Rivauday C, Yao Y, He F, Lu CX, Guagnano V, Metz T, Finan PM, Hofmann F, Sellers WR, Porter JA, Myer VE, Graus-Porta D, Wilson CJ, Buckler A, Tiedt R. Rescue Screens with Secreted Proteins Reveal Compensatory Potential of Receptor Tyrosine Kinases in Driving Cancer Growth. Cancer Discov 2012; 2:948-59. [DOI: 10.1158/2159-8290.cd-12-0237] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Majd H, Viray J, Porter JA, Romberg E, Arola D. Degradation in the fatigue resistance of dentin by bur and abrasive air-jet preparations. J Dent Res 2012; 91:894-9. [PMID: 22851284 DOI: 10.1177/0022034512455800] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The objective of this investigation was to distinguish whether the instruments commonly used for cutting dentin cause degradation in strength or fatigue behavior. Beams of coronal dentin were obtained from unrestored 3(rd) molars and subjected to either quasi-static or cyclic flexural loading to failure. The surfaces of selected beams were treated with a conventional straight-sided bur or with an abrasive air jet laden with glass particles. Under monotonic loading, there was no difference in the strength or Weibull parameters obtained for the control or treated beams. However, the fatigue strength of dentin receiving bur and air-jet treatments was significantly lower (p ≤ 0.0001) than that of the control. The bur treatment resulted in the largest overall degree of degradation, with nearly 40% reduction in the endurance limit and even more substantial decrease in the fatigue life. The methods currently used for cavity preparations substantially degrade the durability of dentin.
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Affiliation(s)
- H Majd
- Department of Mechanical Engineering, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
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Hlivko JT, Esber EJ, Porter JA, Kefalas CH. Small-bowel obstruction precipitated by bowel preparation for screening colonoscopy. Endoscopy 2010; 42 Suppl 2:E220. [PMID: 20878603 DOI: 10.1055/s-0030-1255644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Affiliation(s)
- J T Hlivko
- Department of Medicine, Summa Health System, Akron, Ohio 44304, USA.
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King FJ, Selinger DW, Mapa FA, Janes J, Wu H, Smith TR, Wang QY, Niyomrattanakitand P, Sipes DG, Brinker A, Porter JA, Myer VE. Pathway Reporter Assays Reveal Small Molecule Mechanisms of Action. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.jala.2009.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Cell-based, phenotypic screening of small molecules often identifies compounds with provocative biological properties. However, determining the cellular target(s) and/or mechanism of action (MoA) of lead compounds remains an extremely challenging and time-consuming exercise. To provide insights into a compound's cellular action and greatly reduce the time required for MoA determination, we have developed a screening platform consisting of an extensive series of reporter gene assays (RGAs). A collection of > 11,000 compounds of known MoA (e.g., World Drug Index entries) were screened against the entire panel. The output provided evidence that an RGA signature could be ascribed to numerous, biologically diverse MoAs. The reference database generated suggested novel biological activity for particular compounds. For example, the profiling data led to the prediction that the cellular target of the natural product terprenin was dihydroorotate dehydrogenase (DHODH), which was confirmed experimentally. The screening methodology developed for this endeavor renders it amenable to the future examination of compounds with unknown MoA, in an automated, inexpensive, and time-efficient manner.
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Affiliation(s)
- Frederick J. King
- The Novartis Institute of Biomedical Research, Cambridge, MA
- The Genomics Institute of the Novartis Research Foundation, San Diego, CA
| | | | - Felipa A. Mapa
- The Novartis Institute of Biomedical Research, Cambridge, MA
| | - Jeff Janes
- The Genomics Institute of the Novartis Research Foundation, San Diego, CA
| | - Hua Wu
- The Novartis Institute of Biomedical Research, Cambridge, MA
| | - Timothy R. Smith
- The Genomics Institute of the Novartis Research Foundation, San Diego, CA
| | - Qing-Yin Wang
- The Novartis Institute for Tropical Diseases, The Republic of Singapore
| | | | - Daniel G. Sipes
- The Genomics Institute of the Novartis Research Foundation, San Diego, CA
| | - Achim Brinker
- The Genomics Institute of the Novartis Research Foundation, San Diego, CA
| | | | - Vic E. Myer
- The Novartis Institute of Biomedical Research, Cambridge, MA
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Nicklin P, Bergman P, Zhang B, Triantafellow E, Wang H, Nyfeler B, Yang H, Hild M, Kung C, Wilson C, Myer VE, MacKeigan JP, Porter JA, Wang YK, Cantley LC, Finan PM, Murphy LO. Bidirectional transport of amino acids regulates mTOR and autophagy. Cell 2009; 136:521-34. [PMID: 19203585 DOI: 10.1016/j.cell.2008.11.044] [Citation(s) in RCA: 1285] [Impact Index Per Article: 85.7] [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: 05/30/2008] [Revised: 10/04/2008] [Accepted: 11/21/2008] [Indexed: 01/08/2023]
Abstract
Amino acids are required for activation of the mammalian target of rapamycin (mTOR) kinase which regulates protein translation, cell growth, and autophagy. Cell surface transporters that allow amino acids to enter the cell and signal to mTOR are unknown. We show that cellular uptake of L-glutamine and its subsequent rapid efflux in the presence of essential amino acids (EAA) is the rate-limiting step that activates mTOR. L-glutamine uptake is regulated by SLC1A5 and loss of SLC1A5 function inhibits cell growth and activates autophagy. The molecular basis for L-glutamine sensitivity is due to SLC7A5/SLC3A2, a bidirectional transporter that regulates the simultaneous efflux of L-glutamine out of cells and transport of L-leucine/EAA into cells. Certain tumor cell lines with high basal cellular levels of L-glutamine bypass the need for L-glutamine uptake and are primed for mTOR activation. Thus, L-glutamine flux regulates mTOR, translation and autophagy to coordinate cell growth and proliferation.
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Affiliation(s)
- Paul Nicklin
- Respiratory Diseases Area, Novartis Institutes for BioMedical Research, Novartis Horsham Research Centre, West Sussex, UK
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Abstract
We incorporate density dependence into continuum Born-Green-Yvon (BGY) theory through calculation of the end-to-end intramolecular correlation function. Whereas in previous studies we had only performed this calculation for the case of an isolated (zero-density) square-well chain of m segments (3</=m</=7), here we consider this single chain to have been placed in a square-well monomeric fluid of variable density. We find that the results obtained by this more sophisticated approach are in good agreement with the predictions of both other theories and simulation concerning the structural properties of short chains. Using a homologous series of n-alkanes as a test case, we also conclude that BGY theory, with the current modifications, is capable of describing fluid properties for heptane (n-C7) through nonadecane (n-C19).
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Affiliation(s)
- J A Porter
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, USA
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Abstract
Using a homologous series of n-alkanes as a model system, we compare the predictions of a lattice Born-Green-Yvon (BGY) theory and a continuum BGY theory with experimental results. We find that both theories are capable of describing the fluid properties and critical points of alkanes ranging from heptamers (n-C7) to nonadecamers (n-C19). We probe the connection between the lattice and continuum BGY models and extend our discussion to include a sampling of other lattice and continuum treatments.
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Affiliation(s)
- J A Porter
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, USA
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Lean IJ, Porter JA, Rabiee AR, Morgan WF, Tranter WP, Moss N, Rheinberger RJ. Comparison of effects of GnRH and prostaglandin in combination, and prostaglandin on conception rates and time to conception in dairy cows. Aust Vet J 2003; 81:488-93. [PMID: 15086085 DOI: 10.1111/j.1751-0813.2003.tb13369.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [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: 11/30/2022]
Abstract
OBJECTIVE To assess the effectiveness of a gonadotrophin-releasing hormone (GnRH) / prostaglandin program (GnRH-PG-GnRH, Ovsynch) on conception rates and time to conception of lactating dairy cows compared with a PG program (double prostaglandin injection). DESIGN A randomised multi-centre cohort study was conducted with 778 cows from nine dairy herds. Cows at different stages of lactation were randomly assigned, after matching for days open at the time of treatment, to either the PG or Ovsynch program. PROCEDURE Cows on the PG program received two intramuscular injections of prostaglandin (2 mL, Prosolvin) 11 days apart. The Ovsynch program consisted of two intramuscular injections of GnRH (1 mL, Fertagyl) 9 days apart, separated by one injection of prostaglandin 40 h before the second GnRH injection. Milk samples were taken at the time of artificial insemination and assayed for progesterone by radioimmunoassay. RESULTS The Ovsynch program was not significantly different to PG in achieving conception, with overall conception rates of 37.6% and 41.4%, respectively, for each program. There was, however, a significant interaction between the effects of parity and treatment (P = 0.03), because conception rates were higher in older cows (parity 5 or more) on the PG program than for older cows on the Ovsynch program. There was no significant effect of treatment (P > 0.5) on time to conception after treatment, but older cows were slower to conceive (P < 0.0001). Conception rates differed (P < 0.0001) among herds. CONCLUSION The median days to conception for both groups was 22 and mean days from treatment to conception were 36.3 +/- 3.3 and 31.6 +/- 2.7 for the Ovsynch and PG programs respectively, indicating that reproductive performance of cows was not significantly different with Ovsynch program or PG program. There appears to be a need to evaluate causes of reproductive failure in older cows.
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Affiliation(s)
- I J Lean
- Bovine Research Australasia, PO Box 660, Camden, New South Wales 2570.
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Abstract
Postoperative femoral neuropathy is an uncommon complication of abdominal surgery. We present four cases occurring after colectomy at our institution and discuss the diagnosis and treatment.
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Affiliation(s)
- J P Celebrezze
- Department of General Surgery, Summa Health System, Akron City Hospital, Ohio, USA
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26
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Fuse N, Maiti T, Wang B, Porter JA, Hall TM, Leahy DJ, Beachy PA. Sonic hedgehog protein signals not as a hydrolytic enzyme but as an apparent ligand for patched. Proc Natl Acad Sci U S A 1999; 96:10992-9. [PMID: 10500113 PMCID: PMC34231 DOI: 10.1073/pnas.96.20.10992] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.2] [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: 11/18/2022] Open
Abstract
The amino-terminal signaling domain of the Sonic hedgehog secreted protein (Shh-N), which derives from the Shh precursor through an autoprocessing reaction mediated by the carboxyl-terminal domain, executes multiple functions in embryonic tissue patterning, including induction of ventral and suppression of dorsal cell types in the developing neural tube. An apparent catalytic site within Shh-N is suggested by structural homology to a bacterial carboxypeptidase. We demonstrate here that alteration of residues presumed to be critical for a hydrolytic activity does not cause a loss of inductive activity, thus ruling out catalysis by Shh-N as a requirement for signaling. We favor the alternative, that Shh-N functions primarily as a ligand for the putative receptor Patched (Ptc). This possibility is supported by new evidence for direct binding of Shh-N to Ptc and by a strong correlation between the affinity of Ptc-binding and the signaling potency of Shh-N protein variants carrying alterations of conserved residues in a particular region of the protein surface. These results together suggest that direct Shh-N binding to Ptc is a critical event in transduction of the Shh-N signal.
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Affiliation(s)
- N Fuse
- Department of Molecular Biology, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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27
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Porter JA, Moore GP, Wynn PC. Pro-opiomelanocortin gene expression and translation in ovine skin. Exp Dermatol 1999; 8:361-2. [PMID: 10439277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Affiliation(s)
- J A Porter
- Department of Animal Science, University of Sydney, Camden
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Li HS, Porter JA, Montell C. Requirement for the NINAC kinase/myosin for stable termination of the visual cascade. J Neurosci 1998; 18:9601-6. [PMID: 9822721 PMCID: PMC6793282] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Activation of the Drosophila photoresponse is a rapid process that results in plasma membrane Ca2+ and Na+ conductances. Ca2+ functions in negative feedback regulation of Drosophila vision including deactivation. Protein kinase C (PKC) binds directly to Ca2+ and is required for deactivation. However, the consequences of disrupting phosphorylation of any individual PKC substrate in the Drosophila retina have not been addressed. In the current work, we show that NINAC p174, which consists of a protein kinase domain joined to the head region of myosin heavy chain, is a phosphoprotein and is phosphorylated in vitro by PKC. Mutation of either of two PKC sites in the p174 tail resulted in an unusual defect in deactivation that had not been detected previously for other ninaC alleles or other loci. After cessation of the light stimulus, there appeared to be a transient reactivation of the visual cascade. This phenotype suggests that a mechanism exists to prevent reactivation of the visual cascade and that p174 participates in this process.
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Affiliation(s)
- H S Li
- Departments of Biological Chemistry and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Porter JA. Increasing the use of nonprescription drugs in a group-model HMO. Am J Health Syst Pharm 1998; 55:1357-8, 1361. [PMID: 9659962 DOI: 10.1093/ajhp/55.13.1357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J A Porter
- Primary Care Department of Pharmacy, Kaiser Permanente Rocky Mountain Division, Littleton, CO 80122, USA
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Abstract
Veratrum alkaloids and distal inhibitors of cholesterol biosynthesis have been studied for more than 30 years as potent teratogens capable of inducing cyclopia and other birth defects. Here, it is shown that these compounds specifically block the Sonic hedgehog (Shh) signaling pathway. These teratogens did not prevent the sterol modification of Shh during autoprocessing but rather inhibited the response of target tissues to Shh, possibly acting through the sterol sensing domain within the Patched protein regulator of Shh response.
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Affiliation(s)
- M K Cooper
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Beachy PA, Cooper MK, Young KE, von Kessler DP, Park WJ, Hall TM, Leahy DJ, Porter JA. Multiple roles of cholesterol in hedgehog protein biogenesis and signaling. Cold Spring Harb Symp Quant Biol 1998; 62:191-204. [PMID: 9598352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- P A Beachy
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Hall TM, Porter JA, Young KE, Koonin EV, Beachy PA, Leahy DJ. Crystal structure of a Hedgehog autoprocessing domain: homology between Hedgehog and self-splicing proteins. Cell 1997; 91:85-97. [PMID: 9335337 DOI: 10.1016/s0092-8674(01)80011-8] [Citation(s) in RCA: 206] [Impact Index Per Article: 7.6] [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: 02/05/2023]
Abstract
The approximately 25 kDa carboxy-terminal domain of Drosophila Hedgehog protein (Hh-C) possesses an autoprocessing activity that results in an intramolecular cleavage of full-length Hedgehog protein and covalent attachment of a cholesterol moiety to the newly generated amino-terminal fragment. We have identified a 17 kDa fragment of Hh-C (Hh-C17) active in the initiation of autoprocessing and report here its crystal structure. The Hh-C17 structure comprises two homologous subdomains that appear to have arisen from tandem duplication of a primordial gene. Residues in the Hh-C17 active site have been identified, and their role in Hedgehog autoprocessing probed by site-directed mutagenesis. Aspects of sequence, structure, and reaction mechanism are conserved between Hh-C17 and the self-splicing regions of inteins, permitting reconstruction of a plausible evolutionary history of Hh-C and the inteins.
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Affiliation(s)
- T M Hall
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Frye RF, Matzke GR, Adedoyin A, Porter JA, Branch RA. Validation of the five-drug "Pittsburgh cocktail" approach for assessment of selective regulation of drug-metabolizing enzymes. Clin Pharmacol Ther 1997; 62:365-76. [PMID: 9357387 DOI: 10.1016/s0009-9236(97)90114-4] [Citation(s) in RCA: 174] [Impact Index Per Article: 6.4] [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: 02/05/2023]
Abstract
OBJECTIVES To determine whether the probe drugs caffeine, chlorzoxazone, dapsone, debrisoquin (INN, debrisoquine), and mephenytoin can be simultaneously administered as a metabolic cocktail to estimate in vivo cytochrome P450 (CYP) and N-acetyltransferase enzyme activities. METHODS Fourteen healthy nonsmoking male volunteers (mean age +/- SD, 21.6 +/- 2.2 years) received 100 mg caffeine, 250 mg chlorzoxazone, 100 mg dapsone, 10 mg debrisoquin, and 100 mg mephenytoin individually and in four and five-drug combinations in a randomized manner using a 7 x 7 Latin square. Each drug or drug combination was given orally after an overnight fast, with a minimum 1-week washout between administrations. In each session, urine was collected from 0 to 8 hours and plasma was obtained at 4 and 8 hours after drug administration. Plasma and metabolite concentrations were used to estimate phenotypic trait measures for the efficiency of each drug's metabolism. RESULTS The phenotypic indexes determined for caffeine, chlorzoxazone, dapsone, debrisoquin, and mephenytoin were not significantly different when given alone than when given in combination. The median percentage change of the trait measures observed during administration of all five compounds compared with individual administration ranged from -10.7% for the 6-hydroxychlorzoxazone to chlorzoxazone plasma ratio to +2.2% for the debrisoquin recovery ratio. CONCLUSIONS The results of this study show that caffeine, chlorzoxazone, dapsone, debrisoquin, and mephenytoin in low doses can be simultaneously administered without metabolic interaction. This cocktail approach can thus simultaneously provide independent in vivo phenotypic measures for multiple CYP enzymes and N-acetyltransferase.
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Affiliation(s)
- R F Frye
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, PA 15261, USA
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Saseen JJ, Porter JA, Barnette DJ, Bauman JL, Zajac EJ, Carter BL. Postabsorption concentration peaks with brand-name and generic verapamil: a double-blind, crossover study in elderly hypertensive patients. J Clin Pharmacol 1997; 37:526-34. [PMID: 9208360 DOI: 10.1002/j.1552-4604.1997.tb04331.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [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: 02/04/2023]
Abstract
The pharmacokinetic actions, bioequivalence, and cardiovascular effects of two verapamil products were studied in a randomized, double-blind, crossover study in eight elderly hypertensive patients (median age, 69.5 years; range, 60-79 years) given brand-name or generic immediate-release verapamil in 120-mg twice-daily doses for 14 days. Blood pressures, heart rates, P-R intervals; and serum concentrations of R-/S-verapamil and norverapamil were measured multiple times in patients during the last day of each therapy. Median blood pressure decreased more with generic verapamil than with the brand-name drug, with the largest difference occurring at 0.5 hours (137/74 mmHg versus 144.5/80.5 mmHg; P = 0.05 and 0.091, respectively). Pharmacokinetic parameters were not different for the two products (P < 0.01). However, the generic product, compared with the brand-name drug, had mean area under the concentration-time curve (time 0 to 12 hours) ratios (90% CI) of 1.09 (0.78-1.52), 1.16 (0.87-1.55) and 1.11 (0.81-1.52) for R-, S-, and total verapamil. Seventy concentration peaks (31 with the brand-name drug, 39 with the generic drug) appeared between 8 and 24 hours. Median percentages of increase of these peaks, compared with those of previous concentrations, were 48.3% and 36.3% for brand-name and generic drugs, respectively. Fifty of the 70 peaks (71%) were associated with a stereospecific concentration peak of norverapamil and, temporally, with meals. Our findings suggest that whereas the two verapamil products may not be bioequivalent by Food and Drug Administration criteria, the observed differences in effects were not clinically significant in this elderly population. Multiple concentration peaks after absorption were observed in all patients with both verapamil products and were perhaps related to enterohepatic recirculation.
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Affiliation(s)
- J J Saseen
- Department of Pharmacy Practice, University of Colorado Health Sciences Center, Denver 80262, USA
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Abstract
Splenic injury after colonoscopy is rare. Only 15 cases previously have been reported in the English literature. Partial capsular avulsion is the proposed mechanism of injury. Any condition causing increased splenocolic adhesions may be a predisposing factor to splenic injury. Two cases of splenic injury following colonoscopy are reported in addition to a complete review of the literature.
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Affiliation(s)
- E A Espinal
- Northeastern Ohio Universities College of Medicine, Rootstown 44272, USA
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36
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Bologna RA, Khoudary KP, Danesis GG, Summers JL, Porter JA. Acute appendicitis presenting as a perinephric abscess. J Urol 1996; 156:1758. [PMID: 8863591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- R A Bologna
- Department of Urology, Northeastern Ohio Universities College of Medicine, Akron, USA
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Abstract
Hedgehog (Hh) proteins comprise a family of secreted signaling molecules essential for patterning a variety of structures in animal embryogenesis. During biosynthesis, Hh undergoes an autocleavage reaction, mediated by its carboxyl-terminal domain, that produces a lipid-modified amino-terminal fragment responsible for all known Hh signaling activity. Here it is reported that cholesterol is the lipophilic moiety covalently attached to the amino-terminal signaling domain during autoprocessing and that the carboxyl-terminal domain acts as an intramolecular cholesterol transferase. This use of cholesterol to modify embryonic signaling proteins may account for some of the effects of perturbed cholesterol biosynthesis on animal development.
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Affiliation(s)
- J A Porter
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
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Porter JA, Ekker SC, Park WJ, von Kessler DP, Young KE, Chen CH, Ma Y, Woods AS, Cotter RJ, Koonin EV, Beachy PA. Hedgehog patterning activity: role of a lipophilic modification mediated by the carboxy-terminal autoprocessing domain. Cell 1996; 86:21-34. [PMID: 8689684 DOI: 10.1016/s0092-8674(00)80074-4] [Citation(s) in RCA: 426] [Impact Index Per Article: 15.2] [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: 02/01/2023]
Abstract
Autocatalytic processing mediated by the carboxyterminal domain of the hedgehog (hh) protein precursor (Hh) generates an amino-terminal product that accounts for all known signaling activity. The role of autoprocessing biogenesis of the hh signal has been unclear, since a truncated unprocessed protein lacking all carboxy-terminal domain sequences retains signaling activity. Here, we present evidence that the autoprocessing reaction proceeds via an internal thioester intermediate and results in a covalent modification that increases the hydrophobic character of the signaling domain and influences its spatial and subcellular distribution. We demonstrate that truncated unprocessed amino-terminal protein causes embryonic mispatterning, even when expression is localized to cells that normally express Hh, thus suggesting a role for autoprocessing in spatial regulation of hh signaling. This type of processing also appears to operate in the biogenesis of other novel secreted proteins.
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Affiliation(s)
- J A Porter
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA
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Abstract
OBJECTIVE To describe a new class of antihypertensive agents, the angiotensin II receptor antagonists, with emphasis on the prototype losartan. Pharmacokinetic data and clinical trials are reviewed, as well as adverse reactions, drug interactions, and dosing guidelines. DATA SOURCES A MEDLINE search of English-language literature published from 1966 through 1995 was performed. In addition, Merck and Co. provided bibliographic data on file for losartan. STUDY SELECTION Emphasis was placed on clinical and pharmacokinetic studies in humans. Controlled, double-blind studies were evaluated to assess the efficacy and adverse effect profile of losartan. DATA SYNTHESIS Losartan is a nonpeptide, competitive antagonist of the type I angiotensin II receptor. In comparative clinical trials, losartan appears to have antihypertensive efficacy similar to that of the angiotensin-converting enzyme (ACE) inhibitors. Losartan is well tolerated, with an adverse effect profile similar to that of placebo and a reduced incidence of cough versus that with ACE inhibitors. A combination product consisting of losartan 50 mg and hydrochlorothiazide 12.5 mg has also received approval for the treatment of hypertension. The combination product is not indicated for initial therapy, but is recommended for patients who do not respond adequately to losartan monotherapy. The angiotensin II receptor antagonists are also being investigated for beneficial effects in patients with ventricular hypertrophy, renal disease, and heart failure. CONCLUSIONS Losartan, the first angiotensin II receptor antagonist to receive approval for use in the US, appears to be an effective new antihypertensive agent with an adverse effect profile similar to that of placebo. Losartan may be an alternative for patients who cannot tolerate ACE inhibitors. However, the effect of losartan on mortality remains to be evaluated. The role of the angiotensin II receptor antagonists in areas such as ventricular hypertrophy, renal function, and heart failure has yet to be determined.
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Brummitt CF, Porter JA, Herwaldt BL. Reversible peripheral neuropathy associated with sodium stibogluconate therapy for American cutaneous leishmaniasis. Clin Infect Dis 1996; 22:878-9. [PMID: 8722966 DOI: 10.1093/clinids/22.5.878] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- C F Brummitt
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Hall TM, Porter JA, Beachy PA, Leahy DJ. A potential catalytic site revealed by the 1.7-A crystal structure of the amino-terminal signalling domain of Sonic hedgehog. Nature 1995; 378:212-6. [PMID: 7477329 DOI: 10.1038/378212a0] [Citation(s) in RCA: 167] [Impact Index Per Article: 5.8] [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: 01/25/2023]
Abstract
Within the past few years, members of the hedgehog (hh) family of secreted signalling proteins have emerged as the primary signals generated by certain embryonic patterning centres. In vertebrate embryos, for example, sonic hedgehog expression in the notochord appears to be responsible for the local and long-range induction of ventral cell types within the neural tube and somites (reviewed in refs 1, 2). Protein products encoded by hh family members are synthesized as precursors that undergo autoprocessing to generate an amino-terminal domain that appears to be responsible for both local and long-range signalling activities, and a carboxy-terminal domain that contains the autoprocessing activity. As part of an effort to understand how hh family members participate in cell-to-cell signalling, we have determined and report here the crystal structure at 1.7 A of the amino-terminal domain of murine Sonic hedgehog (Shh-N). The structure revealed a tetrahedrally coordinated zinc ion that appears to be structurally analogous to the zinc coordination sites of zinc hydrolases, such as thermolysin and carboxypeptidase A. This previously unsuspected catalytic site represents a distinct activity from the autoprocessing activity that resides in the carboxy-terminal domain.
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Affiliation(s)
- T M Hall
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Abstract
BACKGROUND Percutaneous endoscopic gastrostomy (PEG) is a safe access procedure for enteral nutrition. The purpose of this investigation is to identify predictive factors for early mortality after PEG. METHODS A retrospective review of the hospital records of 416 patients undergoing PEG from June 1, 1989, through December 31, 1991, was conducted. Patient demographics, admitting diagnosis, indication for PEG, risk factors for early mortality, and cause and date of death were reviewed. Logistic regression analysis was used to develop a model to predict early mortality after PEG. The follow-up period ranged from 1 to 30 months. RESULTS The overall mortality rate in this review was 227 of 416 patients (54.6%). The 7- and 30-day case fatality rates were 39 of 416 (9.4%) and 97 of 416 (23.3%), respectively. Logistic regression analysis showed that urinary tract infection (odds ratio (OR) = 3.05; 95% confidence interval (CI) = 1.45-6.43) and previous aspiration (OR = 6.86; 95% CI = 3.27-14.4) were predictive factors for death at 1 week after PEG. Patients who had both risk factors had a 48.4% probability of dying within 7 days after PEG insertion, whereas those who had no risk factors had a 4.3% probability of death. Urinary tract infection (OR = 2.00; 95% CI = 1.17-3.41), previous aspiration (OR = 3.62; 95% CI = 2.00-6.55), and age greater than 75 years (OR = 2.49; 95% CI = 1.47-4.21) were predictive factors for death at 1 month after PEG. Patients who had all three risk factors had a 67.1% probability of death at 1 month while those who had no risk factors had a 10% probability of death. CONCLUSIONS A subgroup of patients exists that has a very high mortality rate after PEG. Less invasive ways of nutritionally supporting these high-risk patients should be evaluated.
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Affiliation(s)
- V L Light
- Department of Surgery, Akron City Hospital, Ohio, USA
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43
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Abstract
The ninaC locus encodes two unconventional myosins, p132 and p174, consisting of fused protein kinase and myosin head domains expressed in Drosophila photoreceptor cells. NinaC are the major calmodulin-binding proteins in the retina and the NinaC-calmodulin interaction is required for the normal subcellular localization of calmodulin as well as for normal photo-transduction. In the current report, we present evidence for two calmodulin-binding sites in NinaC, C1 and C2, which have different in vitro binding properties. C1 was found to be common to both p132 and p174 while C2 was unique to p174. To address the requirements for calmodulin binding at each site in vivo, we generated transgenic flies expressing ninaC genes deleted for either C1 or C2. We found that the spatial localization of calmodulin depended on binding to both C1 and C2. Furthermore, mutation of either site resulted in a defective photoresponse. A prolonged depolarization afterpotential (PDA) was elicited at lower light intensities than necessary to produce a PDA in wild-type flies. These results suggest that calmodulin binding to both C1 and C2 is required in vivo for termination of phototransduction.
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Affiliation(s)
- J A Porter
- Department of Biological Chemistry, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
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Landau WM, Daube JR, Aminoff MJ, Brey RL, Brooks BR, Deuel RK, Galaburda AM, Porter JA, Rosenbaum RB, Whitham RH. Neuroreality. I. Dedicated demolition of the decade of the brain:the genuine threat to neurologic research from the animal radical right American Academy of Neurology Animal Studies Subcommitte. J Child Neurol 1995; 10:343-5. [PMID: 7499752 DOI: 10.1177/088307389501000501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In this era of budgetary constraints, the biggest threat to continuing biomedical research is often seen as governmental funding cutbacks. However, a much larger threat looms—the antiscientific programs of the various so-called animal rights groups. Unless clinicians and scientists mount a concerted defense of scientific investigation, the repressive antiscience movement will win out and thrust us into a Dark Ages scenario, with only a few gallant enough to maintain scientific thought until another Enlightenment. During World War II, the German clergyman Martin Niemoeller lamented the general apathy that allowed a small group of dedicated ideologues (the Nazi hierarchy) to terrorize the Germans: "In Germany they came first for the Communists, and I didn't speak up because I wasn't a Communist. Then they came for the Jews, and I didn't speak up because I wasn't a Jew. Then they came for the trade unionists, and I didn't speak up because I wasn't a trade unionist. Then they came for the Catholics, and I didn't speak up because I was a Protestant. Then they came for me, and by that time no one was left to speak up." Not dissimilarly, the apathy of clinicians and biomedical scientists has permitted the radical animal rights movement to terrorize researchers and undermine our research freedom. In a call to action, the American Academy of Neurology has developed a statement (in association with the Foundation for Biomedical Research and other groups) on the threat to neurology research. This information was originally published in Neurology (1995;45: 609-610). In order to increase the dissemination of this important warning to clinicians and scientists everywhere, the Journal of Child Neurology in cooperation with the American Academy of Neurology is reprinting that material in this issue.
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Ekker SC, Ungar AR, Greenstein P, von Kessler DP, Porter JA, Moon RT, Beachy PA. Patterning activities of vertebrate hedgehog proteins in the developing eye and brain. Curr Biol 1995; 5:944-55. [PMID: 7583153 DOI: 10.1016/s0960-9822(95)00185-0] [Citation(s) in RCA: 457] [Impact Index Per Article: 15.8] [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: 01/26/2023]
Abstract
BACKGROUND The hedgehog (hh) family of secreted signaling proteins is responsible for developmental patterning in a variety of systems, including the neural tube, limbs and somites. Within the neural tube, at the level of the spinal cord, products of the vertebrate gene sonic hedgehog (shh) are proposed to function as a ventral patterning influence, with the capability of inducing floor plate and motor neurons. RESULTS We report the isolation of tiggy-winkle hedgehog (twhh), a novel member of the zebrafish hh gene family. Both twhh and shh are expressed in the ventral midline of the embryonic zebrafish neural tube and brain, but twhh expression becomes limited to the neural tube, whereas shh is also expressed in the notochord. Both genes are expressed in the developing brain, in domains that include a discrete region in the floor of the diencephalon, located between the sites of the future optic stalks. Using pax-2 and pax-6 as markers of proximo-distal fate within the developing eye, we found that ectopic expression of either hh gene promoted proximal fates and suppressed distal fates. In contrast, proximal fates were lost in cyclops mutant embryos, which lack twhh- and shh-expressing forebrain cells. Both twhh and shh proteins undergo autoproteolytic processing in vivo; a fragment corresponding to the amino-terminal cleavage product was sufficient to carry out all signaling activities associated with twhh in eye and brain development. CONCLUSIONS These findings suggest that secreted signals encoded by members of the hedgehog gene family, emanating from the ventral midline of the neural tube, not only play important roles in dorso-ventral patterning of the brain but also appear to constitute an early patterning activity along the proximo-distal axis of the developing eyes.
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Affiliation(s)
- S C Ekker
- Johns Hopkins University School of Medicine, Department of Molecular Biology and Genetics, Baltimore, Maryland 21205, USA
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López-Martínez A, Chang DT, Chiang C, Porter JA, Ros MA, Simandl BK, Beachy PA, Fallon JF. Limb-patterning activity and restricted posterior localization of the amino-terminal product of Sonic hedgehog cleavage. Curr Biol 1995; 5:791-6. [PMID: 7583126 DOI: 10.1016/s0960-9822(95)00156-4] [Citation(s) in RCA: 154] [Impact Index Per Article: 5.3] [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: 01/26/2023]
Abstract
BACKGROUND Sonic hedgehog (Shh), a vertebrate homolog of the Drosophila segment polarity gene hedgehog (hh), has been implicated in patterning of the developing chick limb. Such a role is suggested by the restricted expression of Shh along the posterior limb bud margin, and by the observation that heterologous cells expressing Shh have limb-polarizing activity resembling that of cells from the polarizing region of the posterior limb bud margin. It has not been demonstrated, however, that the Sonic hedgehog protein (SHH) alone is sufficient for limb patterning. SHH has been shown to undergo autoproteolytic cleavage in vitro, yielding two smaller products. It is of interest, therefore, to determine whether processing of SHH occurs in the developing limb and how such processing influences the function of SHH. RESULTS We demonstrate that SHH is proteolytically processed in developing chick limbs. Grafts of cells expressing SHH protein variants that correspond to individual cleavage products demonstrate that the ability to induce patterned gene expression and to impose morphological pattern upon the limb bud is limited to the amino-terminal product (SHH-N) of SHH proteolytic cleavage. We also demonstrate that bacterially synthesized and purified SHH-N, released from implanted beads, is sufficient for limb-patterning activity. Finally, we show that the endogenous amino-terminal cleavage product is tightly localized to the posterior margin of the limb bud. CONCLUSIONS Our data show that, of the two cleavage products resulting from SHH autoproteolysis, SHH-N expressed in grafted heterologous cells or supplied in purified form is sufficient to impose pattern upon the developing limb. Moreover, the restricted localization of the endogenous amino-terminal SHH cleavage product to the posterior border of the chick limb bud makes it unlikely that its patterning activity results from it being distributed in a broad gradient across the antero-posterior axis. More consistent with the observed localization is a model in which the amino-terminal SHH cleavage product exerts its patterning effects by local induction in or near the polarizing region, initiating a cascade of gene expression that ultimately extends across the developing limb.
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Affiliation(s)
- A López-Martínez
- Department of Anatomy and Neuroscience, University of Wisconsin, Madison 53706, USA
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47
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Abstract
Midbrain dopaminergic neurons, whose loss in adults results in Parkinson's disease, can be specified during embryonic development by a contact-dependent signal from floor plate cells. Here we show that the amino-terminal product of Sonic hedgehog autoproteolysis (SHH-N), an inductive signal expressed by floor plate cells, can induce dopaminergic neurons in vitro. We show further that manipulations to increase the activity of cyclic AMP-dependent protein kinase A, which is known to antagonize hedgehog signaling, can block dopaminergic neuron induction by floor plate cells. Our results and those of other studies indicate that SHH-N can function in a dose-dependent manner to induce different cell types within the neural tube. Our results also provide the basis for a potential cell transplantation therapy for Parkinson's disease.
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Affiliation(s)
- M Hynes
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080, USA
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48
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Fan CM, Porter JA, Chiang C, Chang DT, Beachy PA, Tessier-Lavigne M. Long-range sclerotome induction by sonic hedgehog: direct role of the amino-terminal cleavage product and modulation by the cyclic AMP signaling pathway. Cell 1995; 81:457-65. [PMID: 7736597 DOI: 10.1016/0092-8674(95)90398-4] [Citation(s) in RCA: 278] [Impact Index Per Article: 9.6] [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: 01/26/2023]
Abstract
A long-range signal encoded by the Sonic hedgehog (Shh) gene has been implicated as the ventral patterning influence from the notochord that induces sclerotome and represses dermomyotome in somite differentiation. Long-range effects of hedgehog (hh) signaling have been suggested to result either from local induction of a secondary diffusible signal or from the direct action of the highly diffusible carboxy-terminal product of HH autoproteolytic cleavage. Here we provide evidence that the long-range somite patterning effects of SHH are instead mediated by a direct action of the amino-terminal cleavage product. We also show that pharmacological manipulations to increase the activity of cyclic AMP-dependent protein kinase A can selectively antagonize the effects of the amino-terminal cleavage product. Our results support the operation of a single evolutionarily conserved signaling pathway for both local and direct long-range inductive actions of HH family members.
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Affiliation(s)
- C M Fan
- Howard Hughes Medical Institute, Department of Anatomy, University of California, San Francisco 94143-0452, USA
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49
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Roelink H, Porter JA, Chiang C, Tanabe Y, Chang DT, Beachy PA, Jessell TM. Floor plate and motor neuron induction by different concentrations of the amino-terminal cleavage product of sonic hedgehog autoproteolysis. Cell 1995; 81:445-55. [PMID: 7736596 DOI: 10.1016/0092-8674(95)90397-6] [Citation(s) in RCA: 669] [Impact Index Per Article: 23.1] [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: 01/26/2023]
Abstract
The differentiation of floor plate cells and motor neurons can be induced by Sonic hedgehog (SHH), a secreted signaling protein that undergoes autoproteolytic cleavage to generate amino- and carboxy-terminal products. We have found that both floor plate cells and motor neurons are induced by the amino-terminal cleavage product of SHH (SHH-N). The threshold concentration of SHH-N required for motor neuron induction is about 5-fold lower than that required for floor plate induction. Higher concentrations of SHH-N can induce floor plate cells at the expense of motor neuron differentiation. Our results suggest that the induction of floor plate cells and motor neurons by the notochord in vivo is mediated by exposure of neural plate cells to different concentrations of the amino-terminal product of SHH autoproteolytic cleavage.
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Affiliation(s)
- H Roelink
- Howard Hughes Medical Institute, Columbia University, New York, New York 10032, USA
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50
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Landau WM, Daube JR, Aminoff MJ, Brey RL, Brooks BR, Deuel RK, Galaburda AM, Porter JA, Rosenbaum RB, Whitham RH. Neuroreality I. Dedicated demolition of the Decade of the Brain: the genuine threat to neurologic research from the animal radical right. The American Academy of Neurology Animal Studies Subcommittee. Neurology 1995; 45:609-10. [PMID: 7723943 DOI: 10.1212/wnl.45.4.609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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