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Cordonnier C, Mandalasi M, Gigley J, Wohlfert EA, West CM, Blader IJ. The Toxoplasma oxygen-sensing protein, TgPhyA, is required for resistance to interferon gamma-mediated nutritional immunity in mice. PLoS Biol 2024; 22:e3002690. [PMID: 38857298 PMCID: PMC11192375 DOI: 10.1371/journal.pbio.3002690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/21/2024] [Accepted: 05/23/2024] [Indexed: 06/12/2024] Open
Abstract
As Toxoplasma gondii disseminates through its host, the parasite must sense and adapt to its environment and scavenge nutrients. Oxygen (O2) is one such environmental factor and cytoplasmic prolyl 4-hydroxylases (PHDs) are evolutionarily conserved O2 cellular sensing proteins that regulate responses to changes in O2 availability. Toxoplasma expresses 2 PHDs. One of them, TgPHYa hydroxylates SKP1, a subunit of the SCF-E3 ubiquitin ligase complex. In vitro, TgPHYa is important for growth at low O2 levels. However, studies have yet to examine the role that TgPHYa or any other pathogen-encoded PHD plays in virulence and disease. Using a type II ME49 Toxoplasma TgPHYa knockout, we report that TgPHYa is important for Toxoplasma virulence and brain cyst formation in mice. We further find that while TgPHYa mutant parasites can establish an infection in the gut, they are unable to efficiently disseminate to peripheral tissues because the mutant parasites are unable to survive within recruited immune cells. Since this phenotype was abrogated in IFNγ knockout mice, we studied how TgPHYa mediates survival in IFNγ-treated cells. We find that TgPHYa is not required for release of parasite-encoded effectors into host cells that neutralize anti-parasitic processes induced by IFNγ. In contrast, we find that TgPHYa is required for the parasite to scavenge tryptophan, which is an amino acid whose levels are decreased after IFNγ up-regulates the tryptophan-catabolizing enzyme, indoleamine dioxygenase (IDO). We further find, relative to wild-type mice, that IDO knockout mice display increased morbidity when infected with TgPHYa knockout parasites. Together, these data identify the first parasite mechanism for evading IFNγ-induced nutritional immunity and highlight a novel role that oxygen-sensing proteins play in pathogen growth and virulence.
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Affiliation(s)
- Charlotte Cordonnier
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, United States of America
| | - Msano Mandalasi
- Department of Biochemistry & Molecular Biology, Center for Tropical & Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Jason Gigley
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming, United States of America
| | - Elizabeth A. Wohlfert
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, United States of America
| | - Christopher M. West
- Department of Biochemistry & Molecular Biology, Center for Tropical & Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Ira J. Blader
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, United States of America
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2
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Kawabe Y, Du Q, Narita TB, Bell C, Schilde C, Kin K, Schaap P. Emerging roles for diguanylate cyclase during the evolution of soma in dictyostelia. BMC Ecol Evol 2023; 23:60. [PMID: 37803310 PMCID: PMC10559540 DOI: 10.1186/s12862-023-02169-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 09/25/2023] [Indexed: 10/08/2023] Open
Abstract
BACKGROUND Cyclic di-guanylate (c-di-GMP), synthesized by diguanylate cyclase, is a major second messenger in prokaryotes, where it triggers biofilm formation. The dictyostelid social amoebas acquired diguanylate cyclase (dgcA) by horizontal gene transfer. Dictyostelium discoideum (Ddis) in taxon group 4 uses c-di-GMP as a secreted signal to induce differentiation of stalk cells, the ancestral somatic cell type that supports the propagating spores. We here investigated how this role for c-di-GMP evolved in Dictyostelia by exploring dgcA function in the group 2 species Polysphondylium pallidum (Ppal) and in Polysphondylium violaceum (Pvio), which resides in a small sister clade to group 4. RESULTS Similar to Ddis, dgcA is upregulated after aggregation in Ppal and Pvio and predominantly expressed in the anterior region and stalks of emerging fruiting bodies. DgcA null mutants in Ppal and Pvio made fruiting bodies with very long and thin stalks and only few spores and showed delayed aggregation and larger aggregates, respectively. Ddis dgcA- cells cannot form stalks at all, but showed no aggregation defects. The long, thin stalks of Ppal and Pvio dgcA- mutants were also observed in acaA- mutants in these species. AcaA encodes adenylate cyclase A, which mediates the effects of c-di-GMP on stalk induction in Ddis. Other factors that promote stalk formation in Ddis are DIF-1, produced by the polyketide synthase StlB, low ammonia, facilitated by the ammonia transporter AmtC, and high oxygen, detected by the oxygen sensor PhyA (prolyl 4-hydroxylase). We deleted the single stlB, amtC and phyA genes in Pvio wild-type and dgcA- cells. Neither of these interventions affected stalk formation in Pvio wild-type and not or very mildly exacerbated the long thin stalk phenotype of Pvio dgcA- cells. CONCLUSIONS The study reveals a novel role for c-di-GMP in aggregation, while the reduced spore number in Pvio and Ppal dgcA- is likely an indirect effect, due to depletion of the cell pool by the extended stalk formation. The results indicate that in addition to c-di-GMP, Dictyostelia ancestrally used an as yet unknown factor for induction of stalk formation. The activation of AcaA by c-di-GMP is likely conserved throughout Dictyostelia.
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Affiliation(s)
- Yoshinori Kawabe
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
| | - Qingyou Du
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
| | - Takaaki B Narita
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
- Department of Life Science, Faculty of Advanced Engineering, Chiba Institute of Technology, Chiba, 275-0016, Japan
| | - Craig Bell
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
- West of Scotland Innovation Hub, NHS Greater Glasgow and Clyde, Queen Elizabeth University Hospital, Glasgow, G514LB, UK
| | - Christina Schilde
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
- D'Arcy Thompson Unit, School of Life Sciences, University of Dundee, Dundee, DD14HN, UK
| | - Koryu Kin
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, 08003, Spain
| | - Pauline Schaap
- Molecular Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD15EH, UK.
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3
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Boland AW, Gas-Pascual E, van der Wel H, Kim HW, West CM. Synergy between a cytoplasmic vWFA/VIT protein and a WD40-repeat F-box protein controls development in Dictyostelium. Front Cell Dev Biol 2023; 11:1259844. [PMID: 37779900 PMCID: PMC10539598 DOI: 10.3389/fcell.2023.1259844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Accepted: 08/24/2023] [Indexed: 10/03/2023] Open
Abstract
Like most eukaryotes, the pre-metazoan social amoeba Dictyostelium depends on the SCF (Skp1/cullin-1/F-box protein) family of E3 ubiquitin ligases to regulate its proteome. In Dictyostelium, starvation induces a transition from unicellular feeding to a multicellular slug that responds to external signals to culminate into a fruiting body containing terminally differentiated stalk and spore cells. These transitions are subject to regulation by F-box proteins and O2-dependent posttranslational modifications of Skp1. Here we examine in greater depth the essential role of FbxwD and Vwa1, an intracellular vault protein inter-alpha-trypsin (VIT) and von Willebrand factor-A (vWFA) domain containing protein that was found in the FbxwD interactome by co-immunoprecipitation. Reciprocal co-IPs using gene-tagged strains confirmed the interaction and similar changes in protein levels during multicellular development suggested co-functioning. FbxwD overexpression and proteasome inhibitors did not affect Vwa1 levels suggesting a non-substrate relationship. Forced FbxwD overexpression in slug tip cells where it is normally enriched interfered with terminal cell differentiation by a mechanism that depended on its F-box and RING domains, and on Vwa1 expression itself. Whereas vwa1-disruption alone did not affect development, overexpression of either of its three conserved domains arrested development but the effect depended on Vwa1 expression. Based on structure predictions, we propose that the Vwa1 domains exert their negative effect by artificially activating Vwa1 from an autoinhibited state, which in turn imbalances its synergistic function with FbxwD. Autoinhibition or homodimerization might be relevant to the poorly understood tumor suppressor role of the evolutionarily related VWA5A/BCSC-1 in humans.
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Affiliation(s)
- Andrew W. Boland
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Elisabet Gas-Pascual
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Hanke van der Wel
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Hyun W. Kim
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Christopher M. West
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
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4
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Carrère A, d'Alessandro J, Cochet-Escartin O, Hesnard J, Ghazi N, Rivière C, Anjard C, Detcheverry F, Rieu JP. Microphase separation of living cells. Nat Commun 2023; 14:796. [PMID: 36781863 PMCID: PMC9925768 DOI: 10.1038/s41467-023-36395-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 01/30/2023] [Indexed: 02/15/2023] Open
Abstract
Self-organization of cells is central to a variety of biological systems and physical concepts of condensed matter have proven instrumental in deciphering some of their properties. Here we show that microphase separation, long studied in polymeric materials and other inert systems, has a natural counterpart in living cells. When placed below a millimetric film of liquid nutritive medium, a quasi two-dimensional, high-density population of Dictyostelium discoideum cells spontaneously assembles into compact domains. Their typical size of 100 μm is governed by a balance between competing interactions: an adhesion acting as a short-range attraction and promoting aggregation, and an effective long-range repulsion stemming from aerotaxis in near anoxic condition. Experimental data, a simple model and cell-based simulations all support this scenario. Our findings establish a generic mechanism for self-organization of living cells and highlight oxygen regulation as an emergent organizing principle for biological matter.
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Affiliation(s)
- A Carrère
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - J d'Alessandro
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - O Cochet-Escartin
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - J Hesnard
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - N Ghazi
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - C Rivière
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - C Anjard
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France
| | - F Detcheverry
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France.
| | - J-P Rieu
- University of Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France.
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5
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Boland AW, Gas-Pascual E, Nottingham BL, van der Wel H, Daniel NG, Sheikh MO, Schafer CM, West CM. Oxygen-dependent regulation of E3(SCF)ubiquitin ligases and a Skp1-associated JmjD6 homolog in development of the social amoeba Dictyostelium. J Biol Chem 2022; 298:102305. [PMID: 35933019 PMCID: PMC9485057 DOI: 10.1016/j.jbc.2022.102305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 11/01/2022] Open
Abstract
E3-SCF (Skp1/cullin-1/F-box protein) polyubiquitin ligases activate the proteasomal degradation of over a thousand proteins, but the evolutionary diversification of the F-box protein (FBP) family of substrate receptor subunits has challenged their elucidation in protists. Here, we expand the FBP candidate list in the social amoeba Dictyostelium and show that the Skp1 interactome is highly remodeled as cells transition from growth to multicellular development. Importantly, a subset of candidate FBPs was less represented when the posttranslational hydroxylation and glycosylation of Skp1 was abrogated by deletion of the O2-sensing Skp1 prolyl hydroxylase PhyA. A role for this Skp1 modification for SCF activity was indicated by partial rescue of development, which normally depends on high O2 and PhyA, of phyA-KO cells by proteasomal inhibitors. Further examination of two FBPs, FbxwD and the Jumonji C protein JcdI, suggested that Skp1 was substituted by other factors in phyA-KO cells. Although a double-KO of jcdI and its paralog jcdH did not affect development, overexpression of JcdI increased its sensitivity to O2. JcdI, a nonheme dioxygenase shown to have physiological O2 dependence, is conserved across protists with its F-box and other domains, and is related to the human oncogene JmjD6. Sensitization of JcdI-overexpression cells to O2 depended on its dioxygenase activity and other domains, but not its F-box, which may however be the mediator of its reduced levels in WT relative to Skp1 modification mutant cells. The findings suggest that activation of JcdI by O2 is tempered by homeostatic downregulation via PhyA and association with Skp1.
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Affiliation(s)
- Andrew W Boland
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Elisabet Gas-Pascual
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Braxton L Nottingham
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Hanke van der Wel
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia, USA; Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Nitin G Daniel
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - M Osman Sheikh
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Christopher M Schafer
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Christopher M West
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA; Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
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6
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Rieu JP, Cochet-Escartin O, Anjard C, Demircigil M, Calvez V. Commentary: The Dynamics of Aerotaxis in a Simple Eukaryotic Model. Front Cell Dev Biol 2022; 10:844812. [PMID: 35309919 PMCID: PMC8924511 DOI: 10.3389/fcell.2022.844812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/20/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Jean-Paul Rieu
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Olivier Cochet-Escartin
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Christophe Anjard
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Mete Demircigil
- Institut Camille Jordan, UMR5208, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Vincent Calvez
- Institut Camille Jordan, UMR5208, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
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7
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Kim WD, Mathavarajah S, Huber RJ. The Cellular and Developmental Roles of Cullins, Neddylation, and the COP9 Signalosome in Dictyostelium discoideum. Front Physiol 2022; 13:827435. [PMID: 35586714 PMCID: PMC9108976 DOI: 10.3389/fphys.2022.827435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/03/2022] [Indexed: 12/02/2022] Open
Abstract
Cullins (CULs) are a core component of cullin-RING E3 ubiquitin ligases (CRLs), which regulate the degradation, function, and subcellular trafficking of proteins. CULs are post-translationally regulated through neddylation, a process that conjugates the ubiquitin-like modifier protein neural precursor cell expressed developmentally downregulated protein 8 (NEDD8) to target cullins, as well as non-cullin proteins. Counteracting neddylation is the deneddylase, COP9 signalosome (CSN), which removes NEDD8 from target proteins. Recent comparative genomics studies revealed that CRLs and the CSN are highly conserved in Amoebozoa. A well-studied representative of Amoebozoa, the social amoeba Dictyostelium discoideum, has been used for close to 100 years as a model organism for studying conserved cellular and developmental processes owing to its unique life cycle comprised of unicellular and multicellular phases. The organism is also recognized as an exceptional model system for studying cellular processes impacted by human diseases, including but not limited to, cancer and neurodegeneration. Recent work shows that the neddylation inhibitor, MLN4924 (Pevonedistat), inhibits growth and multicellular development in D. discoideum, which supports previous work that revealed the cullin interactome in D. discoideum and the roles of cullins and the CSN in regulating cellular and developmental processes during the D. discoideum life cycle. Here, we review the roles of cullins, neddylation, and the CSN in D. discoideum to guide future work on using this biomedical model system to further explore the evolutionarily conserved functions of cullins and neddylation.
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Affiliation(s)
- William D. Kim
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
| | | | - Robert J. Huber
- Department of Biology, Trent University, Peterborough, ON, Canada
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8
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Cochet-Escartin O, Demircigil M, Hirose S, Allais B, Gonzalo P, Mikaelian I, Funamoto K, Anjard C, Calvez V, Rieu JP. Hypoxia triggers collective aerotactic migration in Dictyostelium discoideum. eLife 2021; 10:64731. [PMID: 34415238 PMCID: PMC8378850 DOI: 10.7554/elife.64731] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 07/30/2021] [Indexed: 01/26/2023] Open
Abstract
Using a self-generated hypoxic assay, we show that the amoeba Dictyostelium discoideum displays a remarkable collective aerotactic behavior. When a cell colony is covered, cells quickly consume the available oxygen (O2) and form a dense ring moving outwards at constant speed and density. To decipher this collective process, we combined two technological developments: porphyrin-based O2 -sensing films and microfluidic O2 gradient generators. We showed that Dictyostelium cells exhibit aerotactic and aerokinetic response in a low range of O2 concentration indicative of a very efficient detection mechanism. Cell behaviors under self-generated or imposed O2 gradients were modeled using an in silico cellular Potts model built on experimental observations. This computational model was complemented with a parsimonious ‘Go or Grow’ partial differential equation (PDE) model. In both models, we found that the collective migration of a dense ring can be explained by the interplay between cell division and the modulation of aerotaxis.
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Affiliation(s)
- Olivier Cochet-Escartin
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Mete Demircigil
- Institut Camille Jordan, UMR5208, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Satomi Hirose
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.,Institute of Fluid Science, Tohoku University, Sendai, Japan
| | - Blandine Allais
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Philippe Gonzalo
- Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, INSERM 1052, CNRS 5286, Université Lyon 1, Université de Lyon, Lyon, France.,Laboratoire de Biochimie et Pharmacologie, Faculté de médecine de Saint-Etienne, CHU de Saint-Etienne, Saint-Etienne, France
| | - Ivan Mikaelian
- Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, INSERM 1052, CNRS 5286, Université Lyon 1, Université de Lyon, Lyon, France
| | - Kenichi Funamoto
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.,Institute of Fluid Science, Tohoku University, Sendai, Japan.,Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Christophe Anjard
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Vincent Calvez
- Institut Camille Jordan, UMR5208, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
| | - Jean-Paul Rieu
- Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, Villeurbanne, France
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9
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Liu T, Abboud MI, Chowdhury R, Tumber A, Hardy AP, Lippl K, Lohans CT, Pires E, Wickens J, McDonough MA, West CM, Schofield CJ. Biochemical and biophysical analyses of hypoxia sensing prolyl hydroxylases from Dictyostelium discoideum and Toxoplasma gondii. J Biol Chem 2020; 295:16545-16561. [PMID: 32934009 PMCID: PMC7864055 DOI: 10.1074/jbc.ra120.013998] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/14/2020] [Indexed: 12/30/2022] Open
Abstract
In animals, the response to chronic hypoxia is mediated by prolyl hydroxylases (PHDs) that regulate the levels of hypoxia-inducible transcription factor α (HIFα). PHD homologues exist in other types of eukaryotes and prokaryotes where they act on non HIF substrates. To gain insight into the factors underlying different PHD substrates and properties, we carried out biochemical and biophysical studies on PHD homologues from the cellular slime mold, Dictyostelium discoideum, and the protozoan parasite, Toxoplasma gondii, both lacking HIF. The respective prolyl-hydroxylases (DdPhyA and TgPhyA) catalyze prolyl-hydroxylation of S-phase kinase-associated protein 1 (Skp1), a reaction enabling adaptation to different dioxygen availability. Assays with full-length Skp1 substrates reveal substantial differences in the kinetic properties of DdPhyA and TgPhyA, both with respect to each other and compared with human PHD2; consistent with cellular studies, TgPhyA is more active at low dioxygen concentrations than DdPhyA. TgSkp1 is a DdPhyA substrate and DdSkp1 is a TgPhyA substrate. No cross-reactivity was detected between DdPhyA/TgPhyA substrates and human PHD2. The human Skp1 E147P variant is a DdPhyA and TgPhyA substrate, suggesting some retention of ancestral interactions. Crystallographic analysis of DdPhyA enables comparisons with homologues from humans, Trichoplax adhaerens, and prokaryotes, informing on differences in mobile elements involved in substrate binding and catalysis. In DdPhyA, two mobile loops that enclose substrates in the PHDs are conserved, but the C-terminal helix of the PHDs is strikingly absent. The combined results support the proposal that PHD homologues have evolved kinetic and structural features suited to their specific sensing roles.
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Affiliation(s)
- Tongri Liu
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | - Martine I Abboud
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | | | - Anthony Tumber
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | - Adam P Hardy
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | - Kerstin Lippl
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | | | - Elisabete Pires
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | - James Wickens
- Chemistry Research Laboratory, University of Oxford, Oxford, United Kingdom
| | | | - Christopher M West
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
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10
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Mandalasi M, Kim HW, Thieker D, Sheikh MO, Gas-Pascual E, Rahman K, Zhao P, Daniel NG, van der Wel H, Ichikawa HT, Glushka JN, Wells L, Woods RJ, Wood ZA, West CM. A terminal α3-galactose modification regulates an E3 ubiquitin ligase subunit in Toxoplasma gondii. J Biol Chem 2020; 295:9223-9243. [PMID: 32414843 PMCID: PMC7335778 DOI: 10.1074/jbc.ra120.013792] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/14/2020] [Indexed: 12/29/2022] Open
Abstract
Skp1, a subunit of E3 Skp1/Cullin-1/F-box protein ubiquitin ligases, is modified by a prolyl hydroxylase that mediates O2 regulation of the social amoeba Dictyostelium and the parasite Toxoplasma gondii The full effect of hydroxylation requires modification of the hydroxyproline by a pentasaccharide that, in Dictyostelium, influences Skp1 structure to favor assembly of Skp1/F-box protein subcomplexes. In Toxoplasma, the presence of a contrasting penultimate sugar assembled by a different glycosyltransferase enables testing of the conformational control model. To define the final sugar and its linkage, here we identified the glycosyltransferase that completes the glycan and found that it is closely related to glycogenin, an enzyme that may prime glycogen synthesis in yeast and animals. However, the Toxoplasma enzyme catalyzes formation of a Galα1,3Glcα linkage rather than the Glcα1,4Glcα linkage formed by glycogenin. Kinetic and crystallographic experiments showed that the glycosyltransferase Gat1 is specific for Skp1 in Toxoplasma and also in another protist, the crop pathogen Pythium ultimum The fifth sugar is important for glycan function as indicated by the slow-growth phenotype of gat1Δ parasites. Computational analyses indicated that, despite the sequence difference, the Toxoplasma glycan still assumes an ordered conformation that controls Skp1 structure and revealed the importance of nonpolar packing interactions of the fifth sugar. The substitution of glycosyltransferases in Toxoplasma and Pythium by an unrelated bifunctional enzyme that assembles a distinct but structurally compatible glycan in Dictyostelium is a remarkable case of convergent evolution, which emphasizes the importance of the terminal α-galactose and establishes the phylogenetic breadth of Skp1 glycoregulation.
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Affiliation(s)
- Msano Mandalasi
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Hyun W Kim
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - David Thieker
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - M Osman Sheikh
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Elisabet Gas-Pascual
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Kazi Rahman
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Peng Zhao
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Nitin G Daniel
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Hanke van der Wel
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - H Travis Ichikawa
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - John N Glushka
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Lance Wells
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Robert J Woods
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Zachary A Wood
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Christopher M West
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA.
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11
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van der Wel H, Gas-Pascual E, West CM. Skp1 isoforms are differentially modified by a dual function prolyl 4-hydroxylase/N-acety lglucosaminyltransferase in a plant pathogen. Glycobiology 2020; 29:705-714. [PMID: 31281925 DOI: 10.1093/glycob/cwz049] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 06/22/2019] [Accepted: 07/02/2019] [Indexed: 01/01/2023] Open
Abstract
Skp1 is hydroxylated by an O2-dependent prolyl hydroxylase (PhyA) that contributes to O2-sensing in the social amoeba Dictyostelium and the mammalian pathogen Toxoplasma gondii. HO-Skp1 is subject to glycosylation and the resulting pentasaccharide affects Skp1 conformation in a way that influences association of Skp1 with F-box proteins, and potentially the assembly of E3(SCF) ubiquitin ligase complexes that mediate the polyubiquitination of target proteins that are degraded in the 26S-proteasome. To investigate the conservation and specificity of these modifications, we analyzed proteins from the oomycete Pythium ultimum, an important crop plant pathogen. Putative coding sequences for Pythium's predicted PhyA and first glycosyltransferase in the predicted five-enzyme pathway, a GlcNAc-transferase (Gnt1), predict a bifunctional enzyme (Phgt) that, when expressed in Dictyostelium, rescued a knockout of phyA but not gnt1. Though recombinant Phgt was also unable to glycosylate Dictyostelium HO-Skp1, it could hydrolyze UDP-GlcNAc and modify a synthetic hydroxypeptide from Dictyostelium Skp1. Pythium encodes two highly similar Skp1 isoforms, but only Skp1A was efficiently hydroxylated and glycosylated in vitro. While kinetic analysis revealed no evidence for processive processing of Skp1, the physical linkage of the two activities implies dedication to Skp1 in vivo. These findings indicate a widespread occurrence of the Skp1 modification pathway across protist phylogeny, suggest that both Gnt1 and PhyA are specific for Skp1 and indicate that the second Skp1 provides a bypass mechanism for O2-regulation in Pythium and other protists that conserve this gene.
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Affiliation(s)
- Hanke van der Wel
- Department of Biochemistry & Molecular Biology, Center for Tropical & Emerging Global Diseases, Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Elisabet Gas-Pascual
- Department of Biochemistry & Molecular Biology, Center for Tropical & Emerging Global Diseases, Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Christopher M West
- Department of Biochemistry & Molecular Biology, Center for Tropical & Emerging Global Diseases, Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
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12
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Masson N, Keeley TP, Giuntoli B, White MD, Puerta ML, Perata P, Hopkinson RJ, Flashman E, Licausi F, Ratcliffe PJ. Conserved N-terminal cysteine dioxygenases transduce responses to hypoxia in animals and plants. Science 2020; 365:65-69. [PMID: 31273118 DOI: 10.1126/science.aaw0112] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 06/12/2019] [Indexed: 12/13/2022]
Abstract
Organisms must respond to hypoxia to preserve oxygen homeostasis. We identify a thiol oxidase, previously assigned as cysteamine (2-aminoethanethiol) dioxygenase (ADO), as a low oxygen affinity (high-K mO2) amino-terminal cysteine dioxygenase that transduces the oxygen-regulated stability of proteins by the N-degron pathway in human cells. ADO catalyzes the conversion of amino-terminal cysteine to cysteine sulfinic acid and is related to the plant cysteine oxidases that mediate responses to hypoxia by an identical posttranslational modification. We show in human cells that ADO regulates RGS4/5 (regulator of G protein signaling) N-degron substrates, modulates G protein-coupled calcium ion signals and mitogen-activated protein kinase activity, and that its activity extends to other N-cysteine proteins including the angiogenic cytokine interleukin-32. Identification of a conserved enzymatic oxygen sensor in multicellular eukaryotes opens routes to better understanding and therapeutic targeting of adaptive responses to hypoxia.
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Affiliation(s)
- Norma Masson
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Thomas P Keeley
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Beatrice Giuntoli
- Department of Biology, University of Pisa, Via Luca Ghini 13, 56126 Pisa, Italy.,Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Via Guidiccioni 8/10, 56124 Pisa, Italy
| | - Mark D White
- Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Mikel Lavilla Puerta
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Via Guidiccioni 8/10, 56124 Pisa, Italy
| | - Pierdomenico Perata
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Via Guidiccioni 8/10, 56124 Pisa, Italy
| | - Richard J Hopkinson
- Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Emily Flashman
- Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Francesco Licausi
- Department of Biology, University of Pisa, Via Luca Ghini 13, 56126 Pisa, Italy.,Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Via Guidiccioni 8/10, 56124 Pisa, Italy
| | - Peter J Ratcliffe
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK. .,The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
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13
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Langley GW, Abboud MI, Lohans CT, Schofield CJ. Inhibition of a viral prolyl hydroxylase. Bioorg Med Chem 2019; 27:2405-2412. [PMID: 30737136 DOI: 10.1016/j.bmc.2019.01.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/15/2019] [Accepted: 01/21/2019] [Indexed: 12/20/2022]
Abstract
The hydroxylation of prolyl-residues in eukaryotes is important in collagen biosynthesis and in hypoxic signalling. The hypoxia inducible factor (HIF) prolyl hydroxylases (PHDs) are drug targets for the treatment of anaemia, while the procollagen prolyl hydroxylases and other 2-oxoglutarate dependent oxygenases are potential therapeutic targets for treatment of cancer, fibrotic disease, and infection. We describe assay development and inhibition studies for a procollagen prolyl hydroxylase from Paramecium bursaria chlorella virus 1 (vCPH). The results reveal HIF PHD inhibitors in clinical trials also inhibit vCPH. Implications for the targeting of the human PHDs and microbial prolyl hydroxylases are discussed.
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Affiliation(s)
- Gareth W Langley
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Martine I Abboud
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christopher T Lohans
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom.
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14
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Florimond C, Cordonnier C, Taujale R, van der Wel H, Kannan N, West CM, Blader IJ. A Toxoplasma Prolyl Hydroxylase Mediates Oxygen Stress Responses by Regulating Translation Elongation. mBio 2019; 10:e00234-19. [PMID: 30914506 PMCID: PMC6437050 DOI: 10.1128/mbio.00234-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 02/08/2019] [Indexed: 02/08/2023] Open
Abstract
As the protozoan parasite Toxoplasma gondii disseminates through its host, it responds to environmental changes by altering its gene expression, metabolism, and other processes. Oxygen is one variable environmental factor, and properly adapting to changes in oxygen levels is critical to prevent the accumulation of reactive oxygen species and other cytotoxic factors. Thus, oxygen-sensing proteins are important, and among these, 2-oxoglutarate-dependent prolyl hydroxylases are highly conserved throughout evolution. Toxoplasma expresses two such enzymes, TgPHYa, which regulates the SCF-ubiquitin ligase complex, and TgPHYb. To characterize TgPHYb, we created a Toxoplasma strain that conditionally expresses TgPHYb and report that TgPHYb is required for optimal parasite growth under normal growth conditions. However, exposing TgPHYb-depleted parasites to extracellular stress leads to severe decreases in parasite invasion, which is likely due to decreased abundance of parasite adhesins. Adhesin protein abundance is reduced in TgPHYb-depleted parasites as a result of inactivation of the protein synthesis elongation factor eEF2 that is accompanied by decreased rates of translational elongation. In contrast to most other oxygen-sensing proteins that mediate cellular responses to low O2, TgPHYb is specifically required for parasite growth and protein synthesis at high, but not low, O2 tensions as well as resistance to reactive oxygen species. In vivo, reduced TgPHYb expression leads to lower parasite burdens in oxygen-rich tissues. Taken together, these data identify TgPHYb as a sensor of high O2 levels, in contrast to TgPHYa, which supports the parasite at low O2IMPORTANCE Because oxygen plays a key role in the growth of many organisms, cells must know how much oxygen is available. O2-sensing proteins are therefore critical cellular factors, and prolyl hydroxylases are the best-studied type of O2-sensing proteins. In general, prolyl hydroxylases trigger cellular responses to decreased oxygen availability. But, how does a cell react to high levels of oxygen? Using the protozoan parasite Toxoplasma gondii, we discovered a prolyl hydroxylase that allows the parasite to grow at elevated oxygen levels and does so by regulating protein synthesis. Loss of this enzyme also reduces parasite burden in oxygen-rich tissues, indicating that sensing both high and low levels of oxygen impacts the growth and physiology of Toxoplasma.
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Affiliation(s)
- Celia Florimond
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Charlotte Cordonnier
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Rahil Taujale
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, USA
| | - Hanke van der Wel
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Natarajan Kannan
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Christopher M West
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Ira J Blader
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
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15
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Refined control of cell stemness allowed animal evolution in the oxic realm. Nat Ecol Evol 2018; 2:220-228. [DOI: 10.1038/s41559-017-0410-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/10/2017] [Indexed: 12/26/2022]
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16
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Cai X, Yuan Y, Liao Z, Xing K, Zhu C, Xu Y, Yu L, Wang L, Wang S, Zhu X, Gao P, Zhang Y, Jiang Q, Xu P, Shu G. α-Ketoglutarate prevents skeletal muscle protein degradation and muscle atrophy through PHD3/ADRB2 pathway. FASEB J 2018; 32:488-499. [PMID: 28939592 PMCID: PMC6266637 DOI: 10.1096/fj.201700670r] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022]
Abstract
Skeletal muscle atrophy due to excessive protein degradation is the main cause for muscle dysfunction, fatigue, and weakening of athletic ability. Endurance exercise is effective to attenuate muscle atrophy, but the underlying mechanism has not been fully investigated. α-Ketoglutarate (AKG) is a key intermediate of tricarboxylic acid cycle, which is generated during endurance exercise. Here, we demonstrated that AKG effectively attenuated corticosterone-induced protein degradation and rescued the muscle atrophy and dysfunction in a Duchenne muscular dystrophy mouse model. Interestingly, AKG also inhibited the expression of proline hydroxylase 3 (PHD3), one of the important oxidoreductases expressed under hypoxic conditions. Subsequently, we identified the β2 adrenergic receptor (ADRB2) as a downstream target for PHD3. We found AKG inhibited PHD3/ADRB2 interaction and therefore increased the stability of ADRB2. In addition, combining pharmacologic and genetic approaches, we showed that AKG rescues skeletal muscle atrophy and protein degradation through a PHD3/ADRB2 mediated mechanism. Taken together, these data reveal a mechanism for inhibitory effects of AKG on muscle atrophy and protein degradation. These findings not only provide a molecular basis for the potential use of exercise-generated metabolite AKG in muscle atrophy treatment, but also identify PHD3 as a potential target for the development of therapies for muscle wasting.-Cai, X., Yuan, Y., Liao, Z., Xing, K., Zhu, C., Xu, Y., Yu, L., Wang, L., Wang, S., Zhu, X., Gao, P., Zhang, Y., Jiang, Q., Xu, P., Shu, G. α-Ketoglutarate prevents skeletal muscle protein degradation and muscle atrophy through PHD3/ADRB2 pathway.
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MESH Headings
- Animals
- Corticosterone/pharmacology
- Disease Models, Animal
- Ketoglutaric Acids/therapeutic use
- Male
- Metabolic Networks and Pathways/drug effects
- Mice
- Mice, Inbred C57BL
- Mice, Inbred mdx
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/pathology
- Muscle Proteins/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Atrophy/metabolism
- Muscular Atrophy/pathology
- Muscular Atrophy/prevention & control
- Muscular Dystrophy, Duchenne/drug therapy
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Procollagen-Proline Dioxygenase/metabolism
- Protein Stability/drug effects
- Proteolysis/drug effects
- Receptors, Adrenergic, beta-2/metabolism
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Affiliation(s)
- Xingcai Cai
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Yexian Yuan
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Zhengrui Liao
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Kongping Xing
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Canjun Zhu
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Yaqiong Xu
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Lulu Yu
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Lina Wang
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Songbo Wang
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Xiaotong Zhu
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Ping Gao
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Yongliang Zhang
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
| | - Qingyan Jiang
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Pingwen Xu
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Gang Shu
- Guangdong Provincial Key Laboratory of Animal Nutritional Control, South China Agricultural University, Guangzhou, China;
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, China
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17
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Sheikh MO, Thieker D, Chalmers G, Schafer CM, Ishihara M, Azadi P, Woods RJ, Glushka JN, Bendiak B, Prestegard JH, West CM. O 2 sensing-associated glycosylation exposes the F-box-combining site of the Dictyostelium Skp1 subunit in E3 ubiquitin ligases. J Biol Chem 2017; 292:18897-18915. [PMID: 28928219 PMCID: PMC5704474 DOI: 10.1074/jbc.m117.809160] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/12/2017] [Indexed: 11/06/2022] Open
Abstract
Skp1 is a conserved protein linking cullin-1 to F-box proteins in SCF (Skp1/Cullin-1/F-box protein) E3 ubiquitin ligases, which modify protein substrates with polyubiquitin chains that typically target them for 26S proteasome-mediated degradation. In Dictyostelium (a social amoeba), Toxoplasma gondii (the agent for human toxoplasmosis), and other protists, Skp1 is regulated by a unique pentasaccharide attached to hydroxylated Pro-143 within its C-terminal F-box-binding domain. Prolyl hydroxylation of Skp1 contributes to O2-dependent Dictyostelium development, but full glycosylation at that position is required for optimal O2 sensing. Previous studies have shown that the glycan promotes organization of the F-box-binding region in Skp1 and aids in Skp1's association with F-box proteins. Here, NMR and MS approaches were used to determine the glycan structure, and then a combination of NMR and molecular dynamics simulations were employed to characterize the impact of the glycan on the conformation and motions of the intrinsically flexible F-box-binding domain of Skp1. Molecular dynamics trajectories of glycosylated Skp1 whose calculated monosaccharide relaxation kinetics and rotational correlation times agreed with the NMR data indicated that the glycan interacts with the loop connecting two α-helices of the F-box-combining site. In these trajectories, the helices separated from one another to create a more accessible and dynamic F-box interface. These results offer an unprecedented view of how a glycan modification influences a disordered region of a full-length protein. The increased sampling of an open Skp1 conformation can explain how glycosylation enhances interactions with F-box proteins in cells.
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Affiliation(s)
- M Osman Sheikh
- From the Department of Biochemistry and Molecular Biology
- the Complex Carbohydrate Research Center, and
- the Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, and
| | | | - Gordon Chalmers
- the Complex Carbohydrate Research Center, and
- the Department of Computer Science, University of Georgia, Athens, Georgia 30602
| | - Christopher M Schafer
- the Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, and
| | | | | | - Robert J Woods
- From the Department of Biochemistry and Molecular Biology
- the Complex Carbohydrate Research Center, and
| | | | - Brad Bendiak
- the Department of Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045
| | - James H Prestegard
- From the Department of Biochemistry and Molecular Biology
- the Complex Carbohydrate Research Center, and
| | - Christopher M West
- From the Department of Biochemistry and Molecular Biology,
- the Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, and
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18
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Timmins A, Saint-André M, de Visser SP. Understanding How Prolyl-4-hydroxylase Structure Steers a Ferryl Oxidant toward Scission of a Strong C-H Bond. J Am Chem Soc 2017; 139:9855-9866. [PMID: 28657747 DOI: 10.1021/jacs.7b02839] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Prolyl-4-hydroxylase (P4H) is a non-heme iron hydroxylase that regio- and stereospecifically hydroxylates proline residues in a peptide chain into R-4-hydroxyproline, which is essential for collagen cross-linking purposes in the human body. Surprisingly, in P4H, a strong aliphatic C-H bond is activated, while thermodynamically much weaker aliphatic C-H groups, that is, at the C3 and C5 positions, are untouched. Little is known on the origins of the high regio- and stereoselectivity of P4H and many non-heme and heme enzymes in general, and insight into this matter may be relevant to Biotechnology as well as Drug Development. The active site of the protein contains two aromatic residues (Tyr140 and Trp243) that we expected to be crucial for guiding the regioselectivity of the reaction. We performed a detailed quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) study on wild-type and mutant structures. The work shows that Trp243 is involved in key protein loop-loop interactions that affect the shape and size of the substrate binding pocket and its mutation has major long-range effects. By contrast, the Tyr140 residue is shown to guide the regio- and stereoselectivity by holding the substrate and ferryl oxidant in a specific orientation through hydrogen bonding and π-stacking interactions. Compelling evidence is found that the Tyr140 residue is involved in expelling the product from the binding pocket after the reaction is complete. It is shown that mutations where the hydrogen bonding network that involves the Tyr140 and Trp243 residues is disrupted lead to major changes in folding of the protein and the size and shape of the substrate binding pocket. Specifically, the Trp243 residue positions the amino acid side chains of Arg161 and Glu127 in specific orientations with substrate. As such, the P4H enzyme is a carefully designed protein with a subtle and rigid secondary structure that enables the binding of substrate, guides the regioselectivity, and expels product efficiently.
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Affiliation(s)
- Amy Timmins
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester , 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Maud Saint-André
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester , 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Sam P de Visser
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester , 131 Princess Street, Manchester M1 7DN, United Kingdom
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19
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Chinoy ZS, Schafer CM, West CM, Boons GJ. Chemical Synthesis of a Glycopeptide Derived from Skp1 for Probing Protein Specific Glycosylation. Chemistry 2015; 21:11779-87. [PMID: 26179871 DOI: 10.1002/chem.201501598] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Indexed: 01/13/2023]
Abstract
Skp1 is a cytoplasmic and nuclear protein, best known as an adaptor of the SCF family of E3-ubiquitin ligases that label proteins for their degradation. Skp1 in Dictyostelium is posttranslationally modified on a specific hydroxyproline (Hyp) residue by a pentasaccharide, which consists of a Fucα1,2-Galβ-1,3-GlcNAcα core, decorated with two α-linked Gal residues. A glycopeptide derived form Skp1 was prepared to characterize the α-galactosyltransferase (AgtA) that mediates the addition of the α-Gal moieties, and to develop antibodies suitable for tracking the trisaccharide isoform of Skp1 in cells. A strategy was developed for the synthesis of the core trisaccharide-Hyp based on the use of 2-naphthylmethyl (Nap) ethers as permanent protecting groups to allow late stage installation of the Hyp moiety. Tuning of glycosyl donor and acceptor reactivities was critical for achieving high yields and anomeric selectivities of glycosylations. The trisaccharide-Hyp moiety was employed for the preparation of the glycopeptide using microwave-assisted solid phase peptide synthesis. Enzyme kinetic studies revealed that trisaccharide-Hyp and trisaccharide-peptide are poorly recognized by AgtA, indicating the importance of context provided by the native Skp1 protein for engagement with the active site. The trisaccharide-peptide was a potent immunogen capable of generating a rabbit antiserum that was highly selective toward the trisaccharide isoform of full-length Skp1.
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Affiliation(s)
- Zoeisha S Chinoy
- Complex Carbohydrate Research Center and Department of Chemistry, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Christopher M Schafer
- Department of Biochemistry and Molecular Biology and Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 (USA).,Current address: Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, OK 73104 (USA)
| | - Christopher M West
- Department of Biochemistry and Molecular Biology and Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 (USA).,Current address: Dept. of Biochemistry and Molecular Biology, University of Georgia, 120 Green Street, Athens, GA 30602 (USA)
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center and Department of Chemistry, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA).
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20
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West CM, Blader IJ. Oxygen sensing by protozoans: how they catch their breath. Curr Opin Microbiol 2015; 26:41-7. [PMID: 25988702 DOI: 10.1016/j.mib.2015.04.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 04/24/2015] [Indexed: 01/09/2023]
Abstract
Cells must know the local levels of available oxygen and either adapt accordingly or relocate to more favorable environments. Prolyl 4-hydroxylases (P4Hs) are emerging as universal cellular oxygen sensors. In animals, these oxygen sensors respond to decreased oxygen availability by up-regulating hypoxia-inducible transcription factors. In protozoa, the P4Hs appear to activate E3-SCF ubiquitin ligase complexes via a glycosylation-dependent mechanism, potentially to turn over their proteomes. Intracellular parasites are impacted by both types of oxygen-sensing pathways. Since parasites are exposed to diverse oxygen tensions during their life cycles, this review identifies emerging oxygen-sensing mechanisms and discusses how these mechanisms probably contribute to the regulation of unicellular eukaryotes.
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Affiliation(s)
- Christopher M West
- Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, 975 NE 10th St., BRC 417, Oklahoma City, OK 73104, USA.
| | - Ira J Blader
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, 347 Biomedical Research Building, 3435 Main Street, Buffalo, NY 14214, USA
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21
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Karunaratne C, Weldeghiorghis TK, West CM, Taylor CM. Conformational changes associated with post-translational modifications of Pro(143) in Skp1 of Dictyostelium--a dipeptide model system. J Am Chem Soc 2014; 136:15170-5. [PMID: 25250945 PMCID: PMC4227711 DOI: 10.1021/ja5033277] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Indexed: 01/16/2023]
Abstract
Prolyl hydroxylation and subsequent glycosylation of the E3(SCF) ubiquitin ligase subunit Skp1 affects its conformation and its interaction with F-box proteins and, ultimately, O2-sensing in the organism. Taking a reductionist approach to understand the molecular basis for these effects, a series of end-capped Thr-Pro dipeptides was synthesized, tracking the sequential post-translational modifications that occur in the protein. The conformation of the pyrrolidine ring in each compound was gauged via coupling constants ((3)JHα,Hβ) and the electronegativity of the Cγ-substituents by chemical shifts ((13)C). The equilibrium between the cis-trans conformations about the central prolyl peptide bond was investigated by integration of signals corresponding to the two species in the (1)H NMR spectra over a range of temperatures. These studies revealed an increasing preference for the trans-conformation in the order Pro < Hyp < [α-(1,4)GlcNAc]Hyp. Rates for the forward and reverse reactions, determined by magnetization transfer experiments, demonstrated a reduced rate for the trans-to-cis conversion and a significant increase in the cis-to-trans conversion upon hydroxylation of the proline residue in the dipeptide. NOE experiments suggest that the Thr side chain pushes the sugar away from the pyrrolidine ring. These effects, which depended on the presence of the N-terminal Thr residue, offer a mechanism to explain altered properties of the corresponding full-length proteins.
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Affiliation(s)
- Chamini
V. Karunaratne
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Thomas K. Weldeghiorghis
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Christopher M. West
- Department
of Biochemistry & Molecular Biology, Oklahoma Center for Medical
Glycobiology, University of Oklahoma Health
Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Carol M. Taylor
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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22
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Sheikh MO, Xu Y, van der Wel H, Walden P, Hartson SD, West CM. Glycosylation of Skp1 promotes formation of Skp1-cullin-1-F-box protein complexes in dictyostelium. Mol Cell Proteomics 2014; 14:66-80. [PMID: 25341530 DOI: 10.1074/mcp.m114.044560] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
O(2) sensing in diverse protozoa depends on the prolyl 4 hydroxylation of Skp1 and modification of the resulting hydroxyproline with a series of five sugars. In yeast, plants, and animals, Skp1 is associated with F-box proteins. The Skp1-F-box protein heterodimer can, for many F-box proteins, dock onto cullin-1 en route to assembly of the Skp1-cullin-1-F-box protein-Rbx1 subcomplex of E3(SCF)Ub ligases. E3(SCF)Ub ligases conjugate Lys48-polyubiquitin chains onto targets bound to the substrate receptor domains of F-box proteins, preparing them for recognition by the 26S proteasome. In the social amoeba Dictyostelium, we found that O(2) availability was rate-limiting for the hydroxylation of newly synthesized Skp1. To investigate the effect of reduced hydroxylation, we analyzed knockout mutants of the Skp1 prolyl hydroxylase and each of the Skp1 glycosyltransferases. Proteomic analysis of co-immunoprecipitates showed that wild-type cells able to fully glycosylate Skp1 had a greater abundance of an SCF complex containing the cullin-1 homolog CulE and FbxD, a newly described WD40-type F-box protein, than the complexes that predominate in cells defective in Skp1 hydroxylation or glycosylation. Similarly, the previously described FbxA-Skp1CulA complex was also more abundant in glycosylation-competent cells. The CulE interactome also included higher levels of proteasomal regulatory particles when Skp1 was glycosylated, suggesting increased activity consistent with greater association with F-box proteins. Finally, the interactome of FLAG-FbxD was modified when it harbored an F-box mutation that compromised Skp1 binding, consistent with an effect on the abundance of potential substrate proteins. We propose that O(2)-dependent posttranslational glycosylation of Skp1 promotes association with F-box proteins and their engagement in functional E3(SCF)Ub ligases that regulate O(2)-dependent developmental progression.
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Affiliation(s)
- M Osman Sheikh
- From the ‡Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Yuechi Xu
- From the ‡Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Hanke van der Wel
- From the ‡Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Paul Walden
- From the ‡Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Steven D Hartson
- §Department of Biochemistry & Molecular Biology, Oklahoma State University, Stillwater, Oklahoma 74078
| | - Christopher M West
- From the ‡Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
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23
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Sheikh MO, Schafer C, Powell JT, Rodgers KK, Mooers BHM, West CM. Glycosylation of Skp1 affects its conformation and promotes binding to a model f-box protein. Biochemistry 2014; 53:1657-69. [PMID: 24506136 PMCID: PMC3985704 DOI: 10.1021/bi401707y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 02/09/2014] [Indexed: 01/08/2023]
Abstract
In the social amoeba Dictyostelium, Skp1 is hydroxylated on proline 143 and further modified by three cytosolic glycosyltransferases to yield an O-linked pentasaccharide that contributes to O2 regulation of development. Skp1 is an adapter in the Skp1/cullin1/F-box protein family of E3 ubiquitin ligases that targets specific proteins for polyubiquitination and subsequent proteasomal degradation. To investigate the biochemical consequences of glycosylation, untagged full-length Skp1 and several of its posttranslationally modified isoforms were expressed and purified to near homogeneity using recombinant and in vitro strategies. Interaction studies with the soluble mammalian F-box protein Fbs1/Fbg1/OCP1 revealed preferential binding to the glycosylated isoforms of Skp1. This difference correlated with the increased α-helical and decreased β-sheet content of glycosylated Skp1s based on circular dichroism and increased folding order based on small-angle X-ray scattering. A comparison of the molecular envelopes of fully glycosylated Skp1 and the apoprotein indicated that both isoforms exist as an antiparallel dimer that is more compact and extended in the glycosylated state. Analytical gel filtration and chemical cross-linking studies showed a growing tendency of less modified isoforms to dimerize. Considering that regions of free Skp1 are intrinsically disordered and Skp1 can adopt distinct folds when bound to F-box proteins, we propose that glycosylation, which occurs adjacent to the F-box binding site, influences the spectrum of energetically similar conformations that vary inversely in their propensity to dock with Fbs1 or another Skp1. Glycosylation may thus influence Skp1 function by modulating F-box protein binding in cells.
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Affiliation(s)
- M. Osman Sheikh
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Christopher
M. Schafer
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - John T. Powell
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Karla K. Rodgers
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Blaine H. M. Mooers
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Christopher M. West
- Department of Biochemistry and Molecular Biology and Oklahoma Center
for Medical Glycobiology, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
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24
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Schafer CM, Sheikh MO, Zhang D, West CM. Novel regulation of Skp1 by the Dictyostelium AgtA α-galactosyltransferase involves the Skp1-binding activity of its WD40 repeat domain. J Biol Chem 2014; 289:9076-88. [PMID: 24550398 DOI: 10.1074/jbc.m113.528679] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The role of Skp1 as an adaptor protein that links Cullin-1 to F-box proteins in E3 Skp1/Cullin-1/F-box protein (SCF) ubiquitin ligases is well characterized. In the social amoeba Dictyostelium and probably many other unicellular eukaryotes, Skp1 is modified by a pentasaccharide attached to a hydroxyproline near its C terminus. This modification is important for oxygen-sensing during Dictyostelium development and is mediated by a HIF-α type prolyl 4-hydroxylase and five sequentially acting cytoplasmic glycosyltransferase activities. Gene disruption studies show that AgtA, the enzyme responsible for addition of the final two galactose residues, in α-linkages to the Skp1 core trisaccharide, is unexpectedly critical for oxygen-dependent terminal development. AgtA possesses a WD40 repeat domain C-terminal to its single catalytic domain and, by use of domain deletions, binding studies, and enzyme assays, we find that the WD40 repeats confer a salt-sensitive second-site binding interaction with Skp1 that mediates novel catalytic activation in addition to simple substrate recognition. In addition, AgtA binds similarly well to precursor isoforms of Skp1 by a salt-sensitive mechanism that competes with binding to an F-box protein and recognition by early modification enzymes, and the effect of binding is diminished when AgtA modifies Skp1. Genetic studies show that loss of AgtA is more severe when an earlier glycosylation step is blocked, and overexpressed AgtA is deleterious if catalytically inactivated. Together, the findings suggest that AgtA mediates non-enzymatic control of unmodified and substrate precursor forms of Skp1 by a binding mechanism that is normally relieved by switch-like activation of its glycosylation function.
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Affiliation(s)
- Christopher M Schafer
- From the Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
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25
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Place TL, Nauseef JT, Peterson MK, Henry MD, Mezhir JJ, Domann FE. Prolyl-4-hydroxylase 3 (PHD3) expression is downregulated during epithelial-to-mesenchymal transition. PLoS One 2013; 8:e83021. [PMID: 24367580 PMCID: PMC3867438 DOI: 10.1371/journal.pone.0083021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/06/2013] [Indexed: 01/28/2023] Open
Abstract
Prolyl-4-hydroxylation by the intracellular prolyl-4-hydroxylase enzymes (PHD1-3) serves as a master regulator of environmental oxygen sensing. The activity of these enzymes is tightly tied to tumorigenesis, as they regulate cell metabolism and angiogenesis through their control of hypoxia-inducible factor (HIF) stability. PHD3 specifically, is gaining attention for its broad function and rapidly accumulating array of non-HIF target proteins. Data from several recent studies suggest a role for PHD3 in the regulation of cell morphology and cell migration. In this study, we aimed to investigate this role by closely examining the relationship between PHD3 expression and epithelial-to-mesenchymal transition (EMT); a transcriptional program that plays a major role in controlling cell morphology and migratory capacity. Using human pancreatic ductal adenocarcinoma (PDA) cell lines and Madin-Darby Canine Kidney (MDCK) cells, we examined the correlation between several markers of EMT and PHD3 expression. We demonstrated that loss of PHD3 expression in PDA cell lines is highly correlated with a mesenchymal-like morphology and an increase in cell migratory capacity. We also found that induction of EMT in MDCK cells resulted in the specific downregulation of PHD3, whereas the expression of the other HIF-PHD enzymes was not affected. The results of this study clearly support a model by which the basal expression and hypoxic induction of PHD3 is suppressed by the EMT transcriptional program. This may be a novel mechanism by which migratory or metastasizing cells alter signaling through specific pathways that are sensitive to regulation by O2. The identification of downstream pathways that are affected by the suppression of PHD3 expression during EMT may provide important insight into the crosstalk between O2 and the migratory and metastatic potential of tumor cells.
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Affiliation(s)
- Trenton L. Place
- Molecular and Cellular Biology Program, The University of Iowa, Iowa City, Iowa, United States of America
- Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Jones T. Nauseef
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - Maina K. Peterson
- Department of Anatomy and Cell Biology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Michael D. Henry
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - James J. Mezhir
- Department of Surgery, The University of Iowa, Iowa City, Iowa, United States of America
| | - Frederick E. Domann
- Molecular and Cellular Biology Program, The University of Iowa, Iowa City, Iowa, United States of America
- Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
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26
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Place TL, Domann FE. Prolyl-hydroxylase 3: Evolving Roles for an Ancient Signaling Protein. HYPOXIA 2013; 2013:13-17. [PMID: 24672806 PMCID: PMC3963164 DOI: 10.2147/hp.s50091] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The ability of cells to sense oxygen is a highly evolved process that facilitates adaptations to the local oxygen environment and is critical to energy homeostasis. In vertebrates, this process is largely controlled by three intracellular prolyl-4-hydroxylases (PHD) 1–3. These related enzymes share the ability to hydroxylate the hypoxia-inducible transcription factor (HIF), and therefore control the transcription of genes involved in metabolism and vascular recruitment. However, it is becoming increasingly apparent that PHD controls much more than HIF signaling, with PHD3 emerging as an exceptionally unique and functionally diverse PHD isoform. In fact, PHD3-mediated hydroxylation has recently been purported to function in such diverse roles as sympathetic neuronal and muscle development, sepsis, glycolytic metabolism, and cell fate. PHD3 expression is also highly distinct from that of the other PHD enzymes, and varies considerably between different cell types and oxygen concentrations. This review will examine the evolution of oxygen sensing by the HIF family of PHD enzymes, with a specific focus on the complex nature of PHD3 expression and function in mammalian cells.
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Affiliation(s)
- Trenton L Place
- Molecular and Cellular Biology Program, The University of Iowa, Iowa City, Iowa, USA
| | - Frederick E Domann
- Molecular and Cellular Biology Program, The University of Iowa, Iowa City, Iowa, USA ; Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa, USA
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27
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Ratcliffe PJ. Oxygen sensing and hypoxia signalling pathways in animals: the implications of physiology for cancer. J Physiol 2013; 591:2027-42. [PMID: 23401619 DOI: 10.1113/jphysiol.2013.251470] [Citation(s) in RCA: 206] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Studies of regulation of the haematopoietic growth factor erythropoietin led to the unexpected discovery of a widespread system of direct oxygen sensing that regulates gene expression in animals. The oxygen-sensitive signal is generated by a series of non-haem Fe(II)- and 2-oxoglutarate-dependent dioxygenases that catalyse the post-translational hydroxylation of specific residues in the transcription factor hypoxia-inducible factor (HIF). These hydroxylations promote both oxygen-dependent degradation and oxygen-dependent inactivation of HIF, but are suppressed in hypoxia, leading to the accumulation of HIF and assembly of an active transcriptional complex in hypoxic cells. Hypoxia-inducible factor activates an extensive transcriptional cascade that interfaces with other cell signalling pathways, microRNA networks and RNA-protein translational control systems. The relationship of these cellular signalling pathways to the integrated physiology of oxygen homeostasis and the implication of dysregulating these massive physiological pathways in diseases such as cancer are discussed.
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Affiliation(s)
- Peter J Ratcliffe
- Henry Wellcome Building for Molecular Physiology, Old Road Campus, University of Oxford, Oxford OX3 7BN, UK.
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28
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Xu Y, Wang ZA, Green RS, West CM. Role of the Skp1 prolyl-hydroxylation/glycosylation pathway in oxygen dependent submerged development of Dictyostelium. BMC DEVELOPMENTAL BIOLOGY 2012; 12:31. [PMID: 23098648 PMCID: PMC3515798 DOI: 10.1186/1471-213x-12-31] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 10/11/2012] [Indexed: 01/27/2023]
Abstract
Background Oxygen sensing is a near universal signaling modality that, in eukaryotes ranging from protists such as Dictyostelium and Toxoplasma to humans, involves a cytoplasmic prolyl 4-hydroxylase that utilizes oxygen and α-ketoglutarate as potentially rate-limiting substrates. A divergence between the animal and protist mechanisms is the enzymatic target: the animal transcriptional factor subunit hypoxia inducible factor-α whose hydroxylation results in its poly-ubiquitination and proteasomal degradation, and the protist E3SCFubiquitin ligase subunit Skp1 whose hydroxylation might control the stability of other proteins. In Dictyostelium, genetic studies show that hydroxylation of Skp1 by PhyA, and subsequent glycosylation of the hydroxyproline, is required for normal oxygen sensing during multicellular development at an air/water interface. Because it has been difficult to detect an effect of hypoxia on Skp1 hydroxylation itself, the role of Skp1 modification was investigated in a submerged model of Dictyostelium development dependent on atmospheric hyperoxia. Results In static isotropic conditions beneath 70-100% atmospheric oxygen, amoebae formed radially symmetrical cyst-like aggregates consisting of a core of spores and undifferentiated cells surrounded by a cortex of stalk cells. Analysis of mutants showed that cyst formation was inhibited by high Skp1 levels via a hydroxylation-dependent mechanism, and spore differentiation required core glycosylation of Skp1 by a mechanism that could be bypassed by excess Skp1. Failure of spores to differentiate at lower oxygen correlated qualitatively with reduced Skp1 hydroxylation. Conclusion We propose that, in the physiological range, oxygen or downstream metabolic effectors control the timing of developmental progression via activation of newly synthesized Skp1.
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Affiliation(s)
- Yuechi Xu
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, 975 NE 10th St, BRC 413, OUHSC, Oklahoma City, OK 73104, USA
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29
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Durán RV, MacKenzie ED, Boulahbel H, Frezza C, Heiserich L, Tardito S, Bussolati O, Rocha S, Hall MN, Gottlieb E. HIF-independent role of prolyl hydroxylases in the cellular response to amino acids. Oncogene 2012; 32:4549-56. [PMID: 23085753 PMCID: PMC3787797 DOI: 10.1038/onc.2012.465] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 08/03/2012] [Accepted: 08/20/2012] [Indexed: 12/20/2022]
Abstract
Hypoxia-inducible factor (HIF) prolyl hydroxylases (PHDs) are α-ketoglutarate (αKG)-dependent dioxygenases that function as cellular oxygen sensors. However, PHD activity also depends on factors other than oxygen, especially αKG, a key metabolic compound closely linked to amino-acid metabolism. We examined the connection between amino-acid availability and PHD activity. We found that amino-acid starvation leads to αKG depletion and to PHD inactivation but not to HIF stabilization. Furthermore, pharmacologic or genetic inhibition of PHDs induced autophagy and prevented mammalian target of rapamycin complex 1 (mTORC1) activation by amino acids in a HIF-independent manner. Therefore, PHDs sense not only oxygen but also respond to amino acids, constituting a broad intracellular nutrient-sensing network.
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Affiliation(s)
- R V Durán
- 1] Apoptosis and Tumour Metabolism Laboratory, Cancer Research UK, The Beatson Institute for Cancer Research, Switchback Road, Glasgow, UK [2] Biozentrum, University of Basel, Klingelbergstrasse 50/70, Basel, Switzerland
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30
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Xu Y, Brown KM, Wang ZA, van der Wel H, Teygong C, Zhang D, Blader IJ, West CM. The Skp1 protein from Toxoplasma is modified by a cytoplasmic prolyl 4-hydroxylase associated with oxygen sensing in the social amoeba Dictyostelium. J Biol Chem 2012; 287:25098-110. [PMID: 22648409 DOI: 10.1074/jbc.m112.355446] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In diverse types of organisms, cellular hypoxic responses are mediated by prolyl 4-hydroxylases that use O(2) and α-ketoglutarate as substrates to hydroxylate conserved proline residues in target proteins. Whereas in metazoans these enzymes control the stability of the HIFα family of transcription factor subunits, the Dictyostelium enzyme (DdPhyA) contributes to O(2) regulation of development by a divergent mechanism involving hydroxylation and subsequent glycosylation of DdSkp1, an adaptor subunit in E3(SCF) ubiquitin ligases. Sequences related to DdPhyA, DdSkp1, and the glycosyltransferases that cap Skp1 hydroxyproline occur also in the genomes of Toxoplasma and other protists, suggesting that this O(2) sensing mechanism may be widespread. Here we show by disruption of the TgphyA locus that this enzyme is required for Skp1 glycosylation in Toxoplasma and that disrupted parasites grow slowly at physiological O(2) levels. Conservation of cellular function was tested by expression of TgPhyA in DdphyA-null cells. Simple gene replacement did not rescue Skp1 glycosylation, whereas overexpression not only corrected Skp1 modification but also restored the O(2) requirement to a level comparable to that of overexpressed DdPhyA. Bacterially expressed TgPhyA protein can prolyl hydroxylate both Toxoplasma and Dictyostelium Skp1s. Kinetic analyses showed that TgPhyA has similar properties to DdPhyA, including a superimposable dependence on the concentration of its co-substrate α-ketoglutarate. Remarkably, however, TgPhyA had a significantly higher apparent affinity for O(2). The findings suggest that Skp1 hydroxylation by PhyA is a conserved process among protists and that this biochemical pathway may indirectly sense O(2) by detecting the levels of O(2)-regulated metabolites such as α-ketoglutarate.
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Affiliation(s)
- Yuechi Xu
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
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31
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Taylor CM, Karunaratne CV, Xie N. Glycosides of hydroxyproline: some recent, unusual discoveries. Glycobiology 2011; 22:757-67. [PMID: 22190471 DOI: 10.1093/glycob/cwr188] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Glycosides of hydroxyproline (Hyp) in the plant cell wall matrix were discovered by Lamport and co-workers in the 1960s. Since then, much has been learned about these Hyp-rich glycoproteins. The intent of this review was to compare and contrast some less common structural motifs, in nontraditional roles, to uncover themes. Arabinosylation of short-peptide plant hormones is essential for growth, cell differentiation and defense. In a very recent development, prolyl hydroxylase and arabinosyltransferase activity has been shown to have a direct impact on the growth of root hairs in Arabidopsis thaliana. Pollen allergens of mugwort and ragweed contain proline-rich domains that are hydroxylated and glycosylated and play a structural role. In the case of mugwort, this domain also presents a significant immunogenic epitope. Major crops, including tobacco and maize, have been used to express and produce recombinant proteins of mammalian origin. The risks of plant-imposed glycosylation are discussed. In unicellular eukaryotes, Skp1 (a subunit of the E3(SCF) ubiquitin ligase complex) harbors a key Hyp residue that is modified by a linear pentasaccharide. These modifications may be involved in sensing oxygen levels. A few studies have probed the impact of glycosylation on the structure of Hyp-containing peptides. These have necessarily looked at small, synthetic molecules, since natural peptides and proteins are often isolable in only minuscule amounts and/or are heterogeneous in nature. The characterization of native structural motifs, together with the determination of glycopeptide conformation and properties, holds the key to rationalizing nature's architectural design.
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Affiliation(s)
- Carol M Taylor
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
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32
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Zhang D, van der Wel H, Johnson JM, West CM. Skp1 prolyl 4-hydroxylase of dictyostelium mediates glycosylation-independent and -dependent responses to O2 without affecting Skp1 stability. J Biol Chem 2011; 287:2006-16. [PMID: 22128189 DOI: 10.1074/jbc.m111.314021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cytoplasmic prolyl 4-hydroxylases (PHDs) have a primary role in O(2) sensing in animals via modification of the transcriptional factor subunit HIFα, resulting in its polyubiquitination by the E3(VHL)ubiquitin (Ub) ligase and degradation in the 26 S proteasome. Previously thought to be restricted to animals, a homolog (P4H1) of HIFα-type PHDs is expressed in the social amoeba Dictyostelium where it also exhibits characteristics of an O(2) sensor for development. Dictyostelium lacks HIFα, and P4H1 modifies a different protein, Skp1, an adaptor of the SCF class of E3-Ub ligases related to the E3(VHL)Ub ligase that targets animal HIFα. Normally, the HO-Skp1 product of the P4H1 reaction is capped by a GlcNAc sugar that can be subsequently extended to a pentasaccharide by novel glycosyltransferases. To analyze the role of glycosylation, the Skp1 GlcNAc-transferase locus gnt1 was modified with a missense mutation to block catalysis or a stop codon to truncate the protein. Despite the accumulation of the hydroxylated form of Skp1, Skp1 was not destabilized based on metabolic labeling. However, hydroxylation alone allowed for partial correction of the high O(2) requirement of P4H1-null cells, therefore revealing both glycosylation-independent and glycosylation-dependent roles for hydroxylation. Genetic complementation of the latter function required an enzymatically active form of Gnt1. Because the effect of the gnt1 deficiency depended on P4H1, and Skp1 was the only protein labeled when the GlcNAc-transferase was restored to mutant extracts, Skp1 apparently mediates the cellular functions of both P4H1 and Gnt1. Although Skp1 stability itself is not affected by hydroxylation, its modification may affect the stability of targets of Skp1-dependent Ub ligases.
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Affiliation(s)
- Dongmei Zhang
- Department of Biochemistry and Molecular Biology, 975 NE 10th St., BRC 417, OUHSC, Oklahoma City, OK 73104, USA
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Enolase 1 and calreticulin regulate the differentiation and function of mouse mast cells. Cell Signal 2011; 24:60-70. [PMID: 21803152 DOI: 10.1016/j.cellsig.2011.07.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 06/28/2011] [Accepted: 07/13/2011] [Indexed: 10/18/2022]
Abstract
It has become widely accepted that the role of mast cells is not restricted to allergic processes. Thus, mast cells play an important role in innate and adaptive immune responses, but study of proteins related to differentiation of mast cells has not been done yet. Enolase 1 is a glycolytic enzyme expressed in most tissues and calreticulin, known as endoplasmic reticulum (ER) resident chaperon, has multifunctional responses. This study aimed to investigate the effects of these proteins on the differentiation and functions of mouse bone marrow-derived mast cells (BMMCs). To identify the target proteins related to the differentiation of BMMCs, we examined the protein expression pattern of BMMCs using 2-dimensional electrophoresis (2-DE) and MALDI-TOF analysis. Expressions of FcεRIα, surface molecules (c-kit, CD40, CD40L, VCAM-1), tryptase, and cytokines were examined in BMMCs using FACS analysis, Western blot, and RT-PCR respectively. Enolase 1 and calreticulin were transfected into BMMCs, and [Ca(2+)]i levels were determined by confocal microscope, while amounts of TNF-α and LTs were measured by ELISA. Eight proteins were identified by proteomic analysis. Enolase and calreticulin siRNA transfection inhibited the expressions of FcεRIα, surface molecules, tryptase, and cytokine mRNA, which are gradually enhanced during culture periods of BMMCs. Enolase 1 and calreticulin siRNA reduced the [Ca(2+)]i levels, amounts of total TNF-α, and the release of TNF-α and leukotrienes, all of which are increased in the BMMCs activated with antigen/antibody reaction. The data suggest that enolase 1 and calreticulin are important proteins in regulating the differentiation and functions of BMMCs.
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van der Wel H, Johnson JM, Xu Y, Karunaratne CV, Wilson KD, Vohra Y, Boons GJ, Taylor CM, Bendiak B, West CM. Requirements for Skp1 processing by cytosolic prolyl 4(trans)-hydroxylase and α-N-acetylglucosaminyltransferase enzymes involved in O₂ signaling in dictyostelium. Biochemistry 2011; 50:1700-13. [PMID: 21247092 PMCID: PMC3192012 DOI: 10.1021/bi101977w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The social amoeba Dictyostelium expresses a hypoxia inducible factor-α (HIFα) type prolyl 4-hydroxylase (P4H1) and an α-N-acetylglucosaminyltransferase (Gnt1) that sequentially modify proline-143 of Skp1, a subunit of the SCF (Skp1/Cullin/F-box protein) class of E3 ubiquitin ligases. Prior genetic studies have implicated Skp1 and its modification by these enzymes in O(2) regulation of development, suggesting the existence of an ancient O(2)-sensing mechanism related to modification of the transcription factor HIFα by animal prolyl 4-hydroxylases (PHDs). To better understand the role of Skp1 in P4H1-dependent O(2) signaling, biochemical and biophysical studies were conducted to characterize the reaction product and the basis of Skp1 substrate selection by P4H1 and Gnt1. (1)H NMR demonstrated formation of 4(trans)-hydroxyproline as previously found for HIFα, and highly purified P4H1 was inhibited by Krebs cycle intermediates and other compounds that affect animal P4Hs. However, in contrast to hydroxylation of HIFα by PHDs, P4H1 depended on features of full-length Skp1, based on truncation, mutagenesis, and competitive inhibition studies. These features are conserved during animal evolution, as even mammalian Skp1, which lacks the target proline, became a good substrate upon its restoration. P4H1 recognition may depend on features conserved for SCF complex formation as heterodimerization with an F-box protein blocked Skp1 hydroxylation. The hydroxyproline-capping enzyme Gnt1 exhibited similar requirements for Skp1 as a substrate. These and other findings support a model in which the protist P4H1 conditionally hydroxylates Skp1 of E3(SCF)ubiquitin ligases to control half-lives of multiple targets, rather than the mechanism of animal PHDs where individual proteins are hydroxylated leading to ubiquitination by the evolutionarily related E3(VBC)ubiquitin ligases.
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Affiliation(s)
- Hanke van der Wel
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 USA
| | - Jennifer M. Johnson
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 USA
| | - Yuechi Xu
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 USA
| | - Chamini V. Karunaratne
- Department of Chemistry, 742 Choppin Hall, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Kyle D. Wilson
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 USA
| | - Yusuf Vohra
- Dept. of Chemistry and Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602 USA
| | - Geert-Jan Boons
- Dept. of Chemistry and Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602 USA
| | - Carol M. Taylor
- Department of Chemistry, 742 Choppin Hall, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Brad Bendiak
- Department of Cell and Developmental Biology and Structural Biology and Biophysics Program, University of Colorado Denver, Anschutz Medical Campus, Mail Stop 8108, RC-1 South Bldg., L18-12120, 12801 East 17th Avenue, Aurora, CO 80045 USA
| | - Christopher M. West
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 USA
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Sucgang R, Kuo A, Tian X, Salerno W, Parikh A, Feasley CL, Dalin E, Tu H, Huang E, Barry K, Lindquist E, Shapiro H, Bruce D, Schmutz J, Salamov A, Fey P, Gaudet P, Anjard C, Babu MM, Basu S, Bushmanova Y, van der Wel H, Katoh-Kurasawa M, Dinh C, Coutinho PM, Saito T, Elias M, Schaap P, Kay RR, Henrissat B, Eichinger L, Rivero F, Putnam NH, West CM, Loomis WF, Chisholm RL, Shaulsky G, Strassmann JE, Queller DC, Kuspa A, Grigoriev IV. Comparative genomics of the social amoebae Dictyostelium discoideum and Dictyostelium purpureum. Genome Biol 2011; 12:R20. [PMID: 21356102 PMCID: PMC3188802 DOI: 10.1186/gb-2011-12-2-r20] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 12/09/2010] [Accepted: 02/28/2011] [Indexed: 12/28/2022] Open
Abstract
Background The social amoebae (Dictyostelia) are a diverse group of Amoebozoa that achieve multicellularity by aggregation and undergo morphogenesis into fruiting bodies with terminally differentiated spores and stalk cells. There are four groups of dictyostelids, with the most derived being a group that contains the model species Dictyostelium discoideum. Results We have produced a draft genome sequence of another group dictyostelid, Dictyostelium purpureum, and compare it to the D. discoideum genome. The assembly (8.41 × coverage) comprises 799 scaffolds totaling 33.0 Mb, comparable to the D. discoideum genome size. Sequence comparisons suggest that these two dictyostelids shared a common ancestor approximately 400 million years ago. In spite of this divergence, most orthologs reside in small clusters of conserved synteny. Comparative analyses revealed a core set of orthologous genes that illuminate dictyostelid physiology, as well as differences in gene family content. Interesting patterns of gene conservation and divergence are also evident, suggesting function differences; some protein families, such as the histidine kinases, have undergone little functional change, whereas others, such as the polyketide synthases, have undergone extensive diversification. The abundant amino acid homopolymers encoded in both genomes are generally not found in homologous positions within proteins, so they are unlikely to derive from ancestral DNA triplet repeats. Genes involved in the social stage evolved more rapidly than others, consistent with either relaxed selection or accelerated evolution due to social conflict. Conclusions The findings from this new genome sequence and comparative analysis shed light on the biology and evolution of the Dictyostelia.
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Affiliation(s)
- Richard Sucgang
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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Rytkönen KT, Williams TA, Renshaw GM, Primmer CR, Nikinmaa M. Molecular Evolution of the Metazoan PHD–HIF Oxygen-Sensing System. Mol Biol Evol 2011; 28:1913-26. [DOI: 10.1093/molbev/msr012] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Karamzadeh B, Kumar D, Sastry GN, de Visser SP. Steric Factors Override Thermodynamic Driving Force in Regioselectivity of Proline Hydroxylation by Prolyl-4-hydroxylase Enzymes. J Phys Chem A 2010; 114:13234-43. [DOI: 10.1021/jp1089855] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Baharan Karamzadeh
- The Manchester Interdisciplinary Biocenter and the School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom, and Molecular Modelling Group, Indian Institute of Chemical Technology, Hyderabad 500-607, India
| | - Devesh Kumar
- The Manchester Interdisciplinary Biocenter and the School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom, and Molecular Modelling Group, Indian Institute of Chemical Technology, Hyderabad 500-607, India
| | - G. Narahari Sastry
- The Manchester Interdisciplinary Biocenter and the School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom, and Molecular Modelling Group, Indian Institute of Chemical Technology, Hyderabad 500-607, India
| | - Sam P. de Visser
- The Manchester Interdisciplinary Biocenter and the School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom, and Molecular Modelling Group, Indian Institute of Chemical Technology, Hyderabad 500-607, India
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Wang ZA, Singh D, van der Wel H, West CM. Prolyl hydroxylation- and glycosylation-dependent functions of Skp1 in O2-regulated development of Dictyostelium. Dev Biol 2010; 349:283-95. [PMID: 20969846 DOI: 10.1016/j.ydbio.2010.10.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 09/15/2010] [Accepted: 10/11/2010] [Indexed: 11/28/2022]
Abstract
O(2) regulates multicellular development of the social amoeba Dictyostelium, suggesting it may serve as an important cue in its native soil environment. Dictyostelium expresses an HIFα-type prolyl 4-hydroxylase (P4H1) whose levels affect the O(2)-threshold for culmination implicating it as a direct O(2)-sensor, as in animals. But Dictyostelium lacks HIFα, a mediator of animal prolyl 4-hydroxylase signaling, and P4H1 can hydroxylate Pro143 of Skp1, a subunit of E3(SCF)ubiquitin-ligases. Skp1 hydroxyproline then becomes the target of five sequential glycosyltransferase reactions that modulate the O(2)-signal. Here we show that genetically induced changes in Skp1 levels also affect the O(2)-threshold, in opposite direction to that of the modification enzymes suggesting that the latter reduce Skp1 activity. Consistent with this, overexpressed Skp1 is poorly hydroxylated and Skp1 is the only P4H1 substrate detectable in extracts. Effects of Pro143 mutations, and of combinations of Skp1 and enzyme level perturbations, are consistent with pathway modulation of Skp1 activity. However, some effects were not mirrored by changes in modification of the bulk Skp1 pool, implicating a Skp1 subpopulation and possibly additional unknown factors. Altered Skp1 levels also affected other developmental transitions in a modification-dependent fashion. Whereas hydroxylation of animal HIFα results in its polyubiquitination and proteasomal degradation, Dictyostelium Skp1 levels were little affected by its modification status. These data indicate that Skp1 and possibly E3(SCF)ubiquitin-ligase activity modulate O(2)-dependent culmination and other developmental processes, and at least partially mediate the action of the hydroxylation/glycosylation pathway in O(2)-sensing.
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Affiliation(s)
- Zhuo A Wang
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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Loenarz C, Schofield CJ. Physiological and biochemical aspects of hydroxylations and demethylations catalyzed by human 2-oxoglutarate oxygenases. Trends Biochem Sci 2010; 36:7-18. [PMID: 20728359 DOI: 10.1016/j.tibs.2010.07.002] [Citation(s) in RCA: 209] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 07/02/2010] [Accepted: 07/06/2010] [Indexed: 11/19/2022]
Abstract
Pioneering work in the 1960s defined prolyl and lysyl hydroxylations as physiologically important oxygenase-catalyzed modifications in collagen biosynthesis; subsequent studies demonstrated that extracellular epidermal growth factor-like domains were hydroxylated at aspartyl and asparaginyl residues. More recent work on the hypoxia-sensing mechanism in animals has shown that prolyl and asparaginyl hydroxylation of the hypoxia-inducible transcription factor play central roles in sensing hypoxia, by regulating protein-protein interactions in an oxygen-dependent manner. The collective results imply that protein hydroxylation is more common than previously perceived. Most protein hydroxylases employ Fe(II) as a cofactor, and 2-oxoglutarate and oxygen as co-substrates. Related enzymes catalyze the demethylation of N(ɛ)-methyl lysine residues in histones and of N-methylated nucleic acids, as well as hydroxylation of 5-methyl cytosine in DNA and 5-methoxycarbonylmethyluridine at the wobble position of tRNA. The combination of new molecular biological and analytical techniques is likely to reveal further roles for oxygenase-mediated modifications to biomacromolecules.
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Affiliation(s)
- Christoph Loenarz
- Chemistry Research Laboratory and The Oxford Centre for Integrative Systems Biology, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
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Abstract
Posttranslational modifications can cause profound changes in protein function. Typically, these modifications are reversible, and thus provide a biochemical on-off switch. In contrast, proline residues are the substrates for an irreversible reaction that is the most common posttranslational modification in humans. This reaction, which is catalyzed by prolyl 4-hydroxylase (P4H), yields (2S,4R)-4-hydroxyproline (Hyp). The protein substrates for P4Hs are diverse. Likewise, the biological consequences of prolyl hydroxylation vary widely, and include altering protein conformation and protein-protein interactions, and enabling further modification. The best known role for Hyp is in stabilizing the collagen triple helix. Hyp is also found in proteins with collagen-like domains, as well as elastin, conotoxins, and argonaute 2. A prolyl hydroxylase domain protein acts on the hypoxia inducible factor alpha, which plays a key role in sensing molecular oxygen, and could act on inhibitory kappaB kinase and RNA polymerase II. P4Hs are not unique to animals, being found in plants and microbes as well. Here, we review the enzymic catalysts of prolyl hydroxylation, along with the chemical and biochemical consequences of this subtle but abundant posttranslational modification.
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Affiliation(s)
- Kelly L Gorres
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706-1544, USA
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West CM, Wang ZA, van der Wel H. A cytoplasmic prolyl hydroxylation and glycosylation pathway modifies Skp1 and regulates O2-dependent development in Dictyostelium. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1800:160-71. [PMID: 19914348 PMCID: PMC2873859 DOI: 10.1016/j.bbagen.2009.11.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Revised: 11/03/2009] [Accepted: 11/05/2009] [Indexed: 12/13/2022]
Abstract
The soil amoeba Dictyostelium is an obligate aerobe that monitors O(2) for informational purposes in addition to utilizing it for oxidative metabolism. Whereas low O(2) suffices for proliferation, a higher level is required for slugs to culminate into fruiting bodies, and O(2) influences slug polarity, slug migration, and cell-type proportioning. Dictyostelium expresses a cytoplasmic prolyl 4-hydroxylase (P4H1) known to mediate O(2)-sensing in animals, but lacks HIFalpha, a major hydroxylation target whose accumulation directly induces animal hypoxia-dependent transcriptional changes. The O(2)-requirement for culmination is increased by P4H1-gene disruption and reduced by P4H1 overexpression. A target of Dictyostelium P4H1 is Skp1, a subunit of the SCF-class of E3-ubiquitin ligases related to the VBC-class that mediates hydroxylation-dependent degradation of animal HIFalpha. Skp1 is a target of a novel cytoplasmic O-glycosylation pathway that modifies HyPro143 with a pentasaccharide, and glycosyltransferase mutants reveal that glycosylation intermediates have antagonistic effects toward P4H1 in O(2)-signaling. Current evidence indicates that Skp1 is the only glycosylation target in cells, based on metabolic labeling, biochemical complementation, and enzyme specificity studies. Bioinformatics studies suggest that the HyPro-modification pathway existed in the ancestral eukaryotic lineage and was retained in selected modern day unicellular organisms whose life cycles experience varying degrees of hypoxia. It is proposed that, in Dictyostelium and other protists including the agent for human toxoplasmosis Toxoplasma gondii, prolyl hydroxylation and glycosylation mediate O(2)-signaling in hierarchical fashion via Skp1 to control the proteome, directly via degradation rather than indirectly via transcription as found in animals.
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Affiliation(s)
- Christopher M West
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, 975 Northeast Tenth Street, Oklahoma City, OK 73104, USA.
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Wang ZA, van der Wel H, Vohra Y, Buskas T, Boons GJ, West CM. Role of a cytoplasmic dual-function glycosyltransferase in O2 regulation of development in Dictyostelium. J Biol Chem 2009; 284:28896-904. [PMID: 19687007 PMCID: PMC2781435 DOI: 10.1074/jbc.m109.022574] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 07/23/2009] [Indexed: 11/06/2022] Open
Abstract
In the social amoeba Dictyostelium, a terminal step in development is regulated by environmental O(2). Prolyl 4-hydroxylase-1 (P4H1) was previously implicated in mediating the O(2) signal, and P4H1-null cells require elevated O(2) to culminate. The E3-ubiquitin ligase adaptor Skp1 is a P4H1 substrate, and here we investigate the function of PgtA, a dual function beta3-galactosyltransferase/alpha2-fucosyltransferase that contributes the 2nd and 3rd sugars of the pentasaccharide cap formed on Skp1 hydroxyproline. Although pgtA-null cells, whose Skp1 contains only a single sugar (N-acetylglucosamine or GlcNAc), show wild-type O(2) dependence of culmination, cells lacking AgtA, an alpha3-galactosyltransferase required to extend the trisaccharide, require elevated O(2) as for P4H1-null cells. Skp1 is the only detectable protein modified by purified PgtA added to pgtA-null extracts. The basis for specificity of PgtA was investigated using native Skp1 acceptor glycoforms and a novel synthetic peptide containing GlcNAcalpha1,4-hydroxy(trans)proline. Cysteine-alkylation of Skp1 strongly inhibited modification by the PgtA galactosyltransferase but not the fucosyltransferase. Furthermore, native and synthetic Skp1 glycopeptides were poorly galactosylated, not processively fucosylated, and negligibly inhibitory, whereas the fucosyltransferase was active toward small substrates. In addition, the galactosyltransferase exhibited an atypical concentration dependence on UDP-galactose. The results provide the first evidence that Skp1 is the functional target of P4H1 in O(2) regulation, indicate a gatekeeper function for the beta3-galactosyltransferase in the PgtA dual reaction, and identify an unexpected P4H1-dependent yet antagonistic function for PgtA that is reversed by AgtA.
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Affiliation(s)
- Zhuo A. Wang
- From the Department of Biochemistry and Molecular Biology and Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
| | - Hanke van der Wel
- From the Department of Biochemistry and Molecular Biology and Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
| | - Yusuf Vohra
- the Department of Chemistry and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Therese Buskas
- the Department of Chemistry and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Geert-Jan Boons
- the Department of Chemistry and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Christopher M. West
- From the Department of Biochemistry and Molecular Biology and Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104 and
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Abstract
Cellular response to oxygen depletion is mediated by HIF (hypoxia-inducible factor). HIF is a heterodimer consisting of a constitutively expressed subunit (HIFβ) and an oxygen-regulated subunit (HIFα). HIFα stability is regulated by prolyl hydroxylation by PHD (prolyl hydroxylase domain-containing protein) family members. PHD activity depends on the availability of molecular oxygen, making PHDs the oxygen-sensing system in animal cells. However, PHDs have recently been shown to respond to stimuli other than oxygen, such as 2-oxoglutarate (α-ketoglutarate), succinate or fumarate, as illustrated by the pseudo-hypoxic response in succinate dehydrogenase- or fumarate dehydrogenase-deficient tumours. Moreover, HIFα is not the sole PHD effector, suggesting that PHDs have functions that extend beyond oxygen sensing. Currently, we are investigating the role of PHDs in the cellular response to amino acid deprivation, a process regulated by mTOR (mammalian target of rapamycin). The precise mechanism whereby amino acids are signalling to mTOR is not fully understood. Given that 2-oxoglutarate is a limiting co-substrate for PHD activity during normoxia and that 2-oxoglutarate levels depend on amino acid availability, it is possible that PHD activity depends not only on oxygen, but also on amino acid availability, suggesting a global metabolic sensor function for PHDs which could be signalling not only to HIF, but also to mTOR.
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West CM, Nguyen P, van der Wel H, Metcalf T, Sweeney KR, Blader IJ, Erdos GW. Dependence of stress resistance on a spore coat heteropolysaccharide in Dictyostelium. EUKARYOTIC CELL 2009; 8:27-36. [PMID: 18996984 PMCID: PMC2620749 DOI: 10.1128/ec.00398-07] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Accepted: 09/01/2008] [Indexed: 11/20/2022]
Abstract
In Dictyostelium, sporulation occurs synchronously as prespore cells approach the apex of the aerial stalk during culmination. Each prespore cell becomes surrounded by its own coat comprised of a core of crystalline cellulose and a branched heteropolysaccharide sandwiched between heterogeneous cysteine-rich glycoproteins. The function of the heteropolysaccharide, which consists of galactose and N-acetylgalactosamine, is unknown. Two glycosyltransferase-like genes encoding multifunctional proteins, each with predicted features of a heteropolysaccharide synthase, were identified in the Dictyostelium discoideum genome. pgtB and pgtC transcripts were modestly upregulated during early development, and pgtB was further intensely upregulated at the time of heteropolysaccharide accumulation. Disruption of either gene reduced synthase-like activity and blocked heteropolysaccharide formation, based on loss of cytological labeling with a lectin and absence of component sugars after acid hydrolysis. Cell mixing experiments showed that heteropolysaccharide expression is spore cell autonomous, suggesting a physical association with other coat molecules during assembly. Mutant coats expressed reduced levels of crystalline cellulose based on chemical analysis after acid degradation, and cellulose was heterogeneously affected based on flow cytometry and electron microscopy. Mutant coats also contained elevated levels of selected coat proteins but not others and were sensitive to shear. Mutant spores were unusually susceptible to hypertonic collapse and damage by detergent or hypertonic stress. Thus, the heteropolysaccharide is essential for spore integrity, which can be explained by a role in the formation of crystalline cellulose and regulation of the protein content of the coat.
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Affiliation(s)
- Christopher M West
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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Funakoshi Y, Suzuki T. Glycobiology in the cytosol: the bitter side of a sweet world. Biochim Biophys Acta Gen Subj 2008; 1790:81-94. [PMID: 18952151 DOI: 10.1016/j.bbagen.2008.09.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 08/03/2008] [Accepted: 09/11/2008] [Indexed: 01/11/2023]
Abstract
Progress in glycobiology has undergone explosive growth over the past decade with more of the researchers now realizing the importance of glycan chains in various inter- and intracellular processes. However, there is still an area of glycobiology awaiting exploration. This is especially the case for the field of "glycobiology in the cytosol" which remains rather poorly understood. Yet evidence is accumulating to demonstrate that the glycoconjugates and their recognition molecules (i.e. lectins) are often present in this subcellular compartment.
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Affiliation(s)
- Yoko Funakoshi
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako Saitama, 351-0198, Japan
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Glycans in evolution and development. Workshop on glycoscience and development. EMBO Rep 2008; 9:617-22. [PMID: 18566596 DOI: 10.1038/embor.2008.119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 05/23/2008] [Indexed: 11/08/2022] Open
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