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1.
Front Sports Act Living ; 6: 1226233, 2024.
Article in English | MEDLINE | ID: mdl-38425567

ABSTRACT

Theory without relevance for practice in a professional graduate degree has been critiqued by some scholars as a deficit approach when preparing MBA students for the workforce. Scholars and practitioners alike call for more pedagogy in the curriculum with a focus on innovation, creativity, and the involvement of industry practitioners. This paper serves as a case study of a moment in time on Monday, 14 June 2021, when the concept of "pracademics" was realized between two artists and two faculty. Following the transcription of the dialogue between two guest speakers from the Hip Hop world (i.e., Fat Joe and DJ Khaled) and two faculty from the sport management MBA program, the paper analyzes the deeper meaning of their intellectual presence with their expertise in the business of culture (i.e., Hip Hop). Findings reveal how the pairing of Hip Hop artists and faculty in an MBA program can address the innovation gap within global business curricula and models. The broader umbrella of pedagogy and application has implications for other academic disciplines to embrace this concept of pairing academics and industry practitioners.

2.
PLoS Biol ; 20(1): e3001532, 2022 01.
Article in English | MEDLINE | ID: mdl-35085231

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.


Subject(s)
ADAM Proteins/immunology , Colitis/immunology , Extracellular Matrix/metabolism , Fibroblasts/immunology , Intestinal Mucosa/immunology , Mesenchymal Stem Cells/immunology , ADAM Proteins/deficiency , ADAM Proteins/genetics , Animals , Cell Differentiation , Colitis/chemically induced , Colitis/genetics , Colitis/pathology , Colon/immunology , Colon/pathology , Extracellular Matrix/immunology , Fibroblasts/pathology , Fibrosis , Gene Expression Regulation , Humans , Inflammation , Interleukin-11/genetics , Interleukin-11/immunology , Intestinal Mucosa/pathology , Male , Mesenchymal Stem Cells/pathology , Mice , Mice, Inbred C57BL , Sequence Analysis, RNA , Single-Cell Analysis , Sodium Dodecyl Sulfate/administration & dosage , Transcription, Genetic , Transcriptome , Wound Healing/genetics , Wound Healing/immunology
3.
Genome Biol ; 22(1): 292, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34654459

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.


Subject(s)
Bacteria/metabolism , Endoplasmic Reticulum Stress , Gastrointestinal Microbiome , Unfolded Protein Response , Aldehydes/pharmacology , Apoptosis , Dipeptides/pharmacology , Endoplasmic Reticulum Stress/drug effects , HT29 Cells , Humans , Indoles/pharmacology , Macrolides/pharmacology , Tunicamycin/pharmacology , Unfolded Protein Response/drug effects
4.
Cell Host Microbe ; 29(9): 1351-1365.e11, 2021 09 08.
Article in English | MEDLINE | ID: mdl-34403684

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.


Subject(s)
ADP Ribose Transferases/metabolism , Actin Cytoskeleton/metabolism , Bacteroides thetaiotaomicron/metabolism , Bacteroides/metabolism , Epithelial Cells/metabolism , Inosine/metabolism , ADP Ribose Transferases/genetics , Animals , Bacteriophages/genetics , Caco-2 Cells , Cell Line, Tumor , Feces/chemistry , Feces/microbiology , Female , Gastrointestinal Microbiome/genetics , Germ-Free Life , HT29 Cells , Humans , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Male , Mice , Mice, Inbred C57BL , Myosin Heavy Chains/metabolism
5.
Nat Microbiol ; 5(3): 486-497, 2020 03.
Article in English | MEDLINE | ID: mdl-31959971

ABSTRACT

Inflammatory bowel diseases (IBD) are associated with alterations in gut microbial abundances and lumenal metabolite concentrations, but the effects of specific metabolites on the gut microbiota in health and disease remain largely unknown. Here, we analysed the influences of metabolites that are differentially abundant in IBD on the growth and physiology of gut bacteria that are also differentially abundant in IBD. We found that N-acylethanolamines (NAEs), a class of endogenously produced signalling lipids elevated in the stool of IBD patients and a T-cell transfer model of colitis, stimulated growth of species over-represented in IBD and inhibited that of species depleted in IBD in vitro. Using metagenomic sequencing, we recapitulated the effects of NAEs in complex microbial communities ex vivo, with Proteobacteria blooming and Bacteroidetes declining in the presence of NAEs. Metatranscriptomic analysis of the same communities identified components of the respiratory chain as important for the metabolism of NAEs, and this was verified using a mutant deficient for respiratory complex I. In this study, we identified NAEs as a class of metabolites that are elevated in IBD and have the potential to shift gut microbiota towards an IBD-like composition.


Subject(s)
Bacteria/drug effects , Bacteria/growth & development , Ethanolamines/pharmacology , Gastrointestinal Microbiome/drug effects , Inflammatory Bowel Diseases/drug therapy , Animals , Bacteria/genetics , Bacteroidetes/drug effects , Bacteroidetes/isolation & purification , Cohort Studies , Disease Models, Animal , Dysbiosis , Feces/microbiology , Female , Gastrointestinal Microbiome/genetics , Gastrointestinal Microbiome/physiology , Gene Expression Profiling , Humans , Inflammatory Bowel Diseases/microbiology , Male , Metagenome , Mice , Mice, Inbred C57BL , Microbiota/drug effects , Proteobacteria/drug effects , Proteobacteria/isolation & purification , Tandem Mass Spectrometry , Whole Genome Sequencing
6.
Cell Host Microbe ; 25(5): 668-680.e7, 2019 05 08.
Article in English | MEDLINE | ID: mdl-31071294

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.


Subject(s)
Bacteroides thetaiotaomicron/growth & development , Bacteroides thetaiotaomicron/metabolism , Host Microbial Interactions , Intestines/microbiology , Intestines/physiology , Sphingolipids/metabolism , Symbiosis/drug effects , Animals , Germ-Free Life , Homeostasis/drug effects , Inflammatory Bowel Diseases/prevention & control , Intestines/drug effects , Mice
7.
Nat Microbiol ; 4(5): 898, 2019 May.
Article in English | MEDLINE | ID: mdl-30971771

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.

9.
Nat Microbiol ; 4(3): 470-479, 2019 03.
Article in English | MEDLINE | ID: mdl-30559407

ABSTRACT

The human gut microbiome matures towards 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 data sets 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- 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 harboured 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.


Subject(s)
Adaptation, Physiological , Gastrointestinal Microbiome/genetics , Genetic Variation , Genome, Bacterial , Age Factors , Bacteriophages/genetics , Bacteroides/genetics , Bacteroides/virology , Bifidobacterium bifidum/genetics , Bifidobacterium longum/genetics , Child Development , Child, Preschool , Estonia , Feces/microbiology , Female , Finland , Humans , Infant , Longitudinal Studies , Male , Metabolic Networks and Pathways , Metagenomics , Polymorphism, Single Nucleotide , Probiotics , Russia
10.
Nat Microbiol ; 4(2): 293-305, 2019 02.
Article in English | MEDLINE | ID: mdl-30531976

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.


Subject(s)
Gastrointestinal Microbiome , Inflammatory Bowel Diseases/metabolism , Inflammatory Bowel Diseases/microbiology , Biodiversity , Biomarkers/metabolism , Colitis, Ulcerative/immunology , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/microbiology , Crohn Disease/immunology , Crohn Disease/metabolism , Crohn Disease/microbiology , Feces/chemistry , Feces/microbiology , Gastrointestinal Microbiome/genetics , Gastrointestinal Microbiome/immunology , Humans , Inflammation/metabolism , Inflammation/microbiology , Inflammatory Bowel Diseases/immunology , Leukocyte L1 Antigen Complex/analysis , Metabolome , Metagenome
11.
Sci Signal ; 10(496)2017 Sep 12.
Article in English | MEDLINE | ID: mdl-28900043

ABSTRACT

GPR15 is an orphan G protein-coupled receptor (GPCR) that is found in lymphocytes. It functions as a co-receptor of simian immunodeficiency virus and HIV-2 and plays a role in the trafficking of T cells to the lamina propria in the colon and to the skin. We describe the purification from porcine colonic tissue extracts of an agonistic ligand for GPR15 and its functional characterization. In humans, this ligand, which we named GPR15L, is encoded by the gene C10ORF99 and has some features similar to the CC family of chemokines. GPR15L was found in some human and mouse epithelia exposed to the environment, such as the colon and skin. In humans, GPR15L was also abundant in the cervix. In skin, GPR15L was readily detected after immunologic challenge and in human disease, for example, in psoriatic lesions. Allotransplantation of skin from Gpr15l-deficient mice onto wild-type mice resulted in substantial graft protection, suggesting nonredundant roles for GPR15 and GPR15L in the generation of effector T cell responses. Together, these data identify a receptor-ligand pair that is required for immune homeostasis at epithelia and whose modulation may represent an alternative approach to treating conditions affecting the skin such as psoriasis.


Subject(s)
Colon/immunology , Intestinal Mucosa/immunology , Receptors, G-Protein-Coupled/immunology , Skin/immunology , T-Lymphocytes/immunology , Allografts , Animals , Colon/cytology , Female , Humans , Intestinal Mucosa/cytology , Mice , Receptors, G-Protein-Coupled/genetics , Skin/cytology , Skin Transplantation , Swine , T-Lymphocytes/cytology , Transplantation Immunology
12.
Cell Host Microbe ; 22(1): 25-37.e6, 2017 Jul 12.
Article in English | MEDLINE | ID: mdl-28704649

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.


Subject(s)
Indoles/metabolism , Indoles/pharmacology , Inflammation/metabolism , Intestinal Mucosa/microbiology , Peptostreptococcus/metabolism , Symbiosis , Animals , Anti-Inflammatory Agents/pharmacology , Bacteria/classification , Bacteria/genetics , Bacteria/metabolism , Bacteroides/genetics , Bacteroides/metabolism , Clostridiales/genetics , Clostridiales/metabolism , Colon/microbiology , Colon/pathology , Cytokines/metabolism , Dysbiosis/metabolism , Humans , Inflammatory Bowel Diseases , Intestinal Mucosa/injuries , Intestinal Mucosa/metabolism , Intestines/microbiology , Mice , Mucin-2/genetics , Mucin-2/metabolism , Mucins/genetics , Mucins/metabolism , Organoids
14.
Cell ; 165(4): 842-53, 2016 May 05.
Article in English | MEDLINE | ID: mdl-27133167

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.


Subject(s)
Bacteroides/immunology , Diabetes Mellitus, Type 1/immunology , Gastrointestinal Microbiome , Lipopolysaccharides/immunology , Animals , Estonia , Feces/microbiology , Finland , Food Microbiology , Humans , Infant , Mice , Mice, Inbred NOD , Milk, Human/immunology , Russia
15.
Science ; 351(6278): 1199-203, 2016 Mar 11.
Article in English | MEDLINE | ID: mdl-26847545

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, B56ß, 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.


Subject(s)
Autism Spectrum Disorder/drug therapy , Nerve Tissue Proteins/genetics , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Amino Acid Sequence , Animals , Autism Spectrum Disorder/enzymology , Autism Spectrum Disorder/genetics , Chromosome Deletion , Chromosome Disorders/genetics , Chromosomes, Human, Pair 22/genetics , Disease Models, Animal , Down-Regulation , Gene Knockdown Techniques , Humans , Insulin-Like Growth Factor I/metabolism , Mechanistic Target of Rapamycin Complex 1 , Mice , Microfilament Proteins , Molecular Sequence Data , Multiprotein Complexes/metabolism , Neurons/enzymology , Phosphorylation , Protein Phosphatase 2/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/metabolism , Proteomics , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction , TOR Serine-Threonine Kinases/metabolism
16.
Chem Biol ; 22(9): 1228-37, 2015 Sep 17.
Article in English | MEDLINE | ID: mdl-26364931

ABSTRACT

In an attempt to identify novel therapeutics and mechanisms to differentially kill tumor cells using phenotypic screening, we identified N-benzyl indole carbinols (N-BICs), synthetic analogs of the natural product indole-3-carbinol (I3C). To understand the mode of action for the molecules we employed Cancer Cell Line Encyclopedia viability profiling and correlative informatics analysis to identify and ultimately confirm the phase II metabolic enzyme sulfotransferase 1A1 (SULT1A1) as the essential factor for compound selectivity. Further studies demonstrate that SULT1A1 activates the N-BICs by rendering the compounds strong electrophiles which can alkylate cellular proteins and thereby induce cell death. This study demonstrates that the selectivity profile for N-BICs is through conversion by SULT1A1 from an inactive prodrug to an active species that induces cell death and tumor suppression.


Subject(s)
Arylsulfotransferase/metabolism , Benzyl Compounds/pharmacology , Indoles/pharmacology , Animals , Benzyl Compounds/pharmacokinetics , Cell Line, Tumor , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Female , HCT116 Cells , Humans , Indoles/pharmacokinetics , Mice , Mice, Nude , Random Allocation , Xenograft Model Antitumor Assays
17.
Nat Chem Biol ; 10(5): 343-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24633354

ABSTRACT

Hedgehog (Hh) signaling determines cell fate during development and can drive tumorigenesis. We performed a screen for new compounds that can impinge on Hh signaling downstream of Smoothened (Smo). A series of cyclohexyl-methyl aminopyrimidine chemotype compounds ('CMAPs') were identified that could block pathway signaling in a Smo-independent manner. In addition to inhibiting Hh signaling, the compounds generated inositol phosphates through an unknown GPCR. Correlation of GPCR mRNA expression levels with compound activity across cell lines suggested the target to be the orphan receptor GPR39. RNA interference or cDNA overexpression of GPR39 demonstrated that the receptor is necessary for compound activity. We propose a model in which CMAPs activate GPR39, which signals to the Gli transcription factors and blocks signaling. In addition to the discovery of GPR39 as a new target that impinges on Hh signaling, we report on small-molecule modulators of the receptor that will enable in vitro interrogation of GPR39 signaling in different cellular contexts.


Subject(s)
Hedgehog Proteins/antagonists & inhibitors , Receptors, G-Protein-Coupled/metabolism , Chromatography, Affinity , Proteomics , Signal Transduction , Tandem Mass Spectrometry
18.
Microbiol Res ; 169(2-3): 107-20, 2014.
Article in English | MEDLINE | ID: mdl-24360837

ABSTRACT

Due to evolutionary conservation of biology, experimental knowledge captured from genetic studies in eukaryotic model organisms provides insight into human cellular pathways and ultimately physiology. Yeast chemogenomic profiling is a powerful approach for annotating cellular responses to small molecules. Using an optimized platform, we provide the relative sensitivities of the heterozygous and homozygous deletion collections for nearly 1800 biologically active compounds. The data quality enables unique insights into pathways that are sensitive and resistant to a given perturbation, as demonstrated with both known and novel compounds. We present examples of novel compounds that inhibit the therapeutically relevant fatty acid synthase and desaturase (Fas1p and Ole1p), and demonstrate how the individual profiles facilitate hypothesis-driven experiments to delineate compound mechanism of action. Importantly, the scale and diversity of tested compounds yields a dataset where the number of modulated pathways approaches saturation. This resource can be used to map novel biological connections, and also identify functions for unannotated genes. We validated hypotheses generated by global two-way hierarchical clustering of profiles for (i) novel compounds with a similar mechanism of action acting upon microtubules or vacuolar ATPases, and (ii) an un-annotated ORF, YIL060w, that plays a role in respiration in the mitochondria. Finally, we identify and characterize background mutations in the widely used yeast deletion collection which should improve the interpretation of past and future screens throughout the community. This comprehensive resource of cellular responses enables the expansion of our understanding of eukaryotic pathway biology.


Subject(s)
Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/genetics , Antifungal Agents/pharmacology , Biosynthetic Pathways , Drug Resistance, Fungal , Gene Expression Regulation, Fungal , High-Throughput Screening Assays , Molecular Sequence Data , Phylogeny , Saccharomyces cerevisiae/classification , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae Proteins/metabolism
19.
EMBO Rep ; 14(12): 1120-6, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24165923

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.


Subject(s)
Receptors, G-Protein-Coupled/metabolism , Thrombospondins/metabolism , Ubiquitin-Protein Ligases/metabolism , Wnt Signaling Pathway , Amino Acid Motifs , Binding Sites , HEK293 Cells , Humans , Protein Binding , Thrombospondins/chemistry
20.
Chem Biol ; 20(7): 912-21, 2013 Jul 25.
Article in English | MEDLINE | ID: mdl-23890009

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.


Subject(s)
Interleukin-12/antagonists & inhibitors , Interleukin-23/antagonists & inhibitors , Morpholines/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors , Signal Transduction/drug effects , Toll-Like Receptors/metabolism , Triazines/pharmacology , Animals , Cell Line , Cytokines/metabolism , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Gene Expression Regulation/drug effects , Humans , Hydrazones , Mice , Morpholines/metabolism , Protein Binding , Pyrimidines , Substrate Specificity , Triazines/metabolism
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