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Bakti F, Stupperich H, Schmitt K, Valerius O, Köhler AM, Meister C, Strohdiek A, Harting R, Sasse C, Heimel K, Neumann P, Ficner R, Braus GH. Fungal COP9 signalosome assembly requires connection of two trimeric intermediates for integration of intrinsic deneddylase. Proc Natl Acad Sci U S A 2023; 120:e2305049120. [PMID: 37603767 PMCID: PMC10477865 DOI: 10.1073/pnas.2305049120] [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: 03/29/2023] [Accepted: 08/01/2023] [Indexed: 08/23/2023] Open
Abstract
The conserved eight-subunit COP9 signalosome (CSN) is required for multicellular fungal development. The CSN deneddylase cooperates with the Cand1 exchange factor to control replacements of E3 ubiquitin cullin RING ligase receptors, providing specificity to eukaryotic protein degradation. Aspergillus nidulans CSN assembles through a heptameric pre-CSN, which is activated by integration of the catalytic CsnE deneddylase. Combined genetic and biochemical approaches provided the assembly choreography within a eukaryotic cell for native fungal CSN. Interactomes of functional GFP-Csn subunit fusions in pre-CSN deficient fungal strains were compared by affinity purifications and mass spectrometry. Two distinct heterotrimeric CSN subcomplexes were identified as pre-CSN assembly intermediates. CsnA-C-H and CsnD-F-G form independently of CsnB, which connects the heterotrimers to a heptamer and enables subsequent integration of CsnE to form the enzymatically active CSN complex. Surveillance mechanisms control accurate Csn subunit amounts and correct cellular localization for sequential assembly since deprivation of Csn subunits changes the abundance and location of remaining Csn subunits.
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Affiliation(s)
- Fruzsina Bakti
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Helena Stupperich
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Kerstin Schmitt
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Anna M. Köhler
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Cindy Meister
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Anja Strohdiek
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Rebekka Harting
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Christoph Sasse
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Kai Heimel
- Department of Microbial Cell Biology, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Piotr Neumann
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, 37077Goettingen, Germany
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Sarikaya Bayram Ö, Bayram Ö, Karahoda B, Meister C, Köhler AM, Thieme S, Elramli N, Frawley D, McGowan J, Fitzpatrick DA, Schmitt K, de Assis LJ, Valerius O, Goldman GH, Braus GH. F-box receptor mediated control of substrate stability and subcellular location organizes cellular development of Aspergillus nidulans. PLoS Genet 2022; 18:e1010502. [PMID: 36508464 PMCID: PMC9744329 DOI: 10.1371/journal.pgen.1010502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 10/31/2022] [Indexed: 12/14/2022] Open
Abstract
Fungal growth and development are coordinated with specific secondary metabolism. This coordination requires 8 of 74 F-box proteins of the filamentous fungus Aspergillus nidulans. F-box proteins recognize primed substrates for ubiquitination by Skp1-Cul1-Fbx (SCF) E3 ubiquitin RING ligases and degradation by the 26S proteasome. 24 F-box proteins are found in the nuclear fraction as part of SCFs during vegetative growth. 43 F-box proteins interact with SCF proteins during growth, development or stress. 45 F-box proteins are associated with more than 700 proteins that have mainly regulatory roles. This corroborates that accurate surveillance of protein stability is prerequisite for organizing multicellular fungal development. Fbx23 combines subcellular location and protein stability control, illustrating the complexity of F-box mediated regulation during fungal development. Fbx23 interacts with epigenetic methyltransferase VipC which interacts with fungal NF-κB-like velvet domain regulator VeA that coordinates fungal development with secondary metabolism. Fbx23 prevents nuclear accumulation of methyltransferase VipC during early development. These results suggest that in addition to their role in protein degradation, F-box proteins also control subcellular accumulations of key regulatory proteins for fungal development.
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Affiliation(s)
| | - Özgür Bayram
- Biology Department, Maynooth University, Maynooth, Co. Kildare, Ireland
- * E-mail: (ÖB); (GHB)
| | - Betim Karahoda
- Biology Department, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Cindy Meister
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Anna M. Köhler
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Sabine Thieme
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Nadia Elramli
- Biology Department, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Dean Frawley
- Biology Department, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Jamie McGowan
- Biology Department, Maynooth University, Maynooth, Co. Kildare, Ireland
| | | | - Kerstin Schmitt
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Leandro Jose de Assis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
- * E-mail: (ÖB); (GHB)
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3
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Meszka I, Polanowska J, Xirodimas DP. Mixed in chains: NEDD8 polymers in the Protein Quality Control system. Semin Cell Dev Biol 2022; 132:27-37. [PMID: 35078718 DOI: 10.1016/j.semcdb.2022.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 12/14/2022]
Abstract
Post-translational modification of proteins with the Ubiquitin-like molecule NEDD8 is a critical regulatory mechanism for several biological processes and a potential target for therapeutic intervention. The role of NEDD8 has been mainly characterised through its modification as single moiety on the cullin family of proteins and control of Cullin-Ring-Ligases, but also on non-cullin substrates. In addition to monoNEDDylation, recent studies have now revealed that NEDD8 can also generate diverse polymers. This is either through modification of the 9 available lysines in NEDD8 and the formation of polyNEDD8 chains, or NEDDylation of Ubiquitin and SUMO-2 for the generation of hybrid NEDD8 chains. Here, we review recent findings that characterise the formation of NEDD8 polymers under distinct modes of protein NEDDylation (canonical/atypical) and their potential role as regulatory signals of the proteotoxic stress response and the Protein Quality Control system.
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Affiliation(s)
- Igor Meszka
- CRBM, Univ. Montpellier, CNRS, Montpellier, France
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4
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USP48 and A20 synergistically promote cell survival in Helicobacter pylori infection. Cell Mol Life Sci 2022; 79:461. [PMID: 35913642 PMCID: PMC9343311 DOI: 10.1007/s00018-022-04489-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/24/2022] [Accepted: 07/11/2022] [Indexed: 12/02/2022]
Abstract
The human pathogen Helicobacter pylori represents a risk factor for the development of gastric diseases including cancer. The H. pylori-induced transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is involved in the pro-inflammatory response and cell survival in the gastric mucosa, and represents a trailblazer of gastric pathophysiology. Termination of nuclear NF-κB heterodimer RelA/p50 activity is regulated by the ubiquitin-RING-ligase complex elongin-cullin-suppressor of cytokine signalling 1 (ECSSOCS1), which leads to K48-ubiquitinylation and degradation of RelA. We found that deubiquitinylase (DUB) ubiquitin specific protease 48 (USP48), which interacts with the COP9 signalosome (CSN) subunit CSN1, stabilises RelA by deubiquitinylation and thereby promotes the transcriptional activity of RelA to prolong de novo synthesis of DUB A20 in H. pylori infection. An important role of A20 is the suppression of caspase-8 activity and apoptotic cell death. USP48 thus enhances the activity of A20 to reduce apoptotic cell death in cells infected with H. pylori. Our results, therefore, define a synergistic mechanism by which USP48 and A20 regulate RelA and apoptotic cell death in H. pylori infection.
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5
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Yang K, Tian J, Keller NP. Post-translational modifications drive secondary metabolite biosynthesis in Aspergillus: a review. Environ Microbiol 2022; 24:2857-2881. [PMID: 35645150 PMCID: PMC9545273 DOI: 10.1111/1462-2920.16034] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 04/23/2022] [Accepted: 04/26/2022] [Indexed: 12/26/2022]
Abstract
Post‐translational modifications (PTMs) are important for protein function and regulate multiple cellular processes and secondary metabolites (SMs) in fungi. Aspergillus species belong to a genus renown for an abundance of bioactive secondary metabolites, many important as toxins, pharmaceuticals and in industrial production. The genes required for secondary metabolites are typically co‐localized in biosynthetic gene clusters (BGCs), which often localize in heterochromatic regions of genome and are ‘turned off’ under laboratory condition. Efforts have been made to ‘turn on’ these BGCs by genetic manipulation of histone modifications, which could convert the heterochromatic structure to euchromatin. Additionally, non‐histone PTMs also play critical roles in the regulation of secondary metabolism. In this review, we collate the known roles of epigenetic and PTMs on Aspergillus SM production. We also summarize the proteomics approaches and bioinformatics tools for PTM identification and prediction and provide future perspectives on the emerging roles of PTM on regulation of SM biosynthesis in Aspergillus and other fungi.
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Affiliation(s)
- Kunlong Yang
- School of Life Science, Jiangsu Normal University, Xuzhou, 221116, Jiangsu Province, People's Republic of China.,Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, 53705, USA
| | - Jun Tian
- School of Life Science, Jiangsu Normal University, Xuzhou, 221116, Jiangsu Province, People's Republic of China
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, 53705, USA
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6
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Wilson AM, Wilken PM, Wingfield MJ, Wingfield BD. Genetic Networks That Govern Sexual Reproduction in the Pezizomycotina. Microbiol Mol Biol Rev 2021; 85:e0002021. [PMID: 34585983 PMCID: PMC8485983 DOI: 10.1128/mmbr.00020-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Sexual development in filamentous fungi is a complex process that relies on the precise control of and interaction between a variety of genetic networks and pathways. The mating-type (MAT) genes are the master regulators of this process and typically act as transcription factors, which control the expression of genes involved at all stages of the sexual cycle. In many fungi, the sexual cycle typically begins when the mating pheromones of one mating type are recognized by a compatible partner, followed by physical interaction and fertilization. Subsequently, highly specialized sexual structures are formed, within which the sexual spores develop after rounds of meiosis and mitosis. These spores are then released and germinate, forming new individuals that initiate new cycles of growth. This review provides an overview of the known genetic networks and pathways that are involved in each major stage of the sexual cycle in filamentous ascomycete fungi.
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Affiliation(s)
- Andi M. Wilson
- Forestry and Agricultural Biotechnology Institute, Department of Biochemistry, Genetics, and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - P. Markus Wilken
- Forestry and Agricultural Biotechnology Institute, Department of Biochemistry, Genetics, and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Michael J. Wingfield
- Forestry and Agricultural Biotechnology Institute, Department of Biochemistry, Genetics, and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Brenda D. Wingfield
- Forestry and Agricultural Biotechnology Institute, Department of Biochemistry, Genetics, and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
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7
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Essential Role of COP9 Signalosome Subunit 5 (Csn5) in Insect Pathogenicity and Asexual Development of Beauveria bassiana. J Fungi (Basel) 2021; 7:jof7080642. [PMID: 34436181 PMCID: PMC8401740 DOI: 10.3390/jof7080642] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/01/2021] [Accepted: 08/03/2021] [Indexed: 12/25/2022] Open
Abstract
Csn5 is a subunit ofthe COP9/signalosome complex in model fungi. Here, we report heavier accumulation of orthologous Csn5 in the nucleus than in the cytoplasm and its indispensability to insect pathogenicity and virulence-related cellular events of Beauveria bassiana. Deletion of csn5 led to a 68% increase in intracellular ubiquitin accumulation and the dysregulation of 18 genes encoding ubiquitin-activating (E1), -conjugating (E2), and -ligating (E3) enzymes and ubiquitin-specific proteases, suggesting the role of Csn5 in balanced ubiquitination/deubiquitination. Consequently, the deletion mutant displayed abolished insect pathogenicity, marked reductions in conidial hydrophobicity and adherence to the insect cuticle, the abolished secretion of cuticle penetration-required enzymes, blocked haemocoel colonisation, and reduced conidiation capacity despite unaffected biomass accumulation. These phenotypes correlated well with sharply repressed or abolished expressions of key hydrophobin genes required for hydrophobin biosynthesis/assembly and of developmental activator genes essential for aerial conidiation and submerged blastospore production. In the mutant, increased sensitivities to heat shock and oxidative stress also correlated with reduced expression levels of several heat-responsive genes and decreased activities of antioxidant enzymes. Altogether, Csn5-reliant ubiquitination/deubiquitination balance coordinates the expression of those crucial genes and the quality control of functionally important enzymes, which are collectively essential for fungal pathogenicity, virulence-related cellular events, and asexual development.
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8
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Salogiannis J, Christensen JR, Songster LD, Aguilar-Maldonado A, Shukla N, Reck-Peterson SL. PxdA interacts with the DipA phosphatase to regulate peroxisome hitchhiking on early endosomes. Mol Biol Cell 2021; 32:492-503. [PMID: 33476181 PMCID: PMC8101442 DOI: 10.1091/mbc.e20-08-0559] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In canonical microtubule-based transport, adaptor proteins link cargoes to dynein and kinesin motors. Recently, an alternative mode of transport known as “hitchhiking” was discovered, where cargoes achieve motility by hitching a ride on already-motile cargoes, rather than attaching to a motor protein. Hitchhiking has been best studied in two filamentous fungi, Aspergillus nidulans and Ustilago maydis. In U. maydis, ribonucleoprotein complexes, peroxisomes, lipid droplets (LDs), and endoplasmic reticulum hitchhike on early endosomes (EEs). In A. nidulans, peroxisomes hitchhike using a putative molecular linker, peroxisome distribution mutant A (PxdA), which associates with EEs. However, whether other organelles use PxdA to hitchhike on EEs is unclear, as are the molecular mechanisms that regulate hitchhiking. Here we find that the proper distribution of LDs, mitochondria, and preautophagosomes do not require PxdA, suggesting that PxdA is a peroxisome-specific molecular linker. We identify two new pxdA alleles, including a point mutation (R2044P) that disrupts PxdA’s ability to associate with EEs and reduces peroxisome movement. We also identify a novel regulator of peroxisome hitchhiking, the phosphatase DipA. DipA colocalizes with EEs and its association with EEs relies on PxdA. Together, our data suggest that PxdA and the DipA phosphatase are specific regulators of peroxisome hitchhiking on EEs.
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Affiliation(s)
- John Salogiannis
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Jenna R Christensen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Livia D Songster
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093
| | - Adriana Aguilar-Maldonado
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Nandini Shukla
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 043210.,Department of Molecular Genetics, The Ohio State University, Columbus, OH 043210
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
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9
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Pick E. The necessity of NEDD8/Rub1 for vitality and its association with mitochondria-derived oxidative stress. Redox Biol 2020; 37:101765. [PMID: 33099217 PMCID: PMC7582104 DOI: 10.1016/j.redox.2020.101765] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/12/2020] [Accepted: 10/16/2020] [Indexed: 01/04/2023] Open
Abstract
Access of molecular oxygen to the respiratory electron transport chain at the mitochondria costs in the generation of reactive oxygen-derived species (ROS). ROS induces progressive damage to macromolecules in all living cells, hence, rapid defense mechanisms to maintain cellular redox homeostasis are vital. NEDD8/Rub1 is a highly conserved ubiquitin-like modifier that has recently been identified as a key regulator of cellular redox homeostasis. In this review, I will present NEDD8/Rub1, its modification cascade of enzymes, substrates and hydrolases. After introduction, I will show that the NEDD8/Rub1 pathway is linked with mitochondria physiology, namely, oxidative stress. In the rest of the review, I will approach the Ascomycota phylum of the kingdom fungi instrumentally, to present existing links between NEDD8/Rub1 vitality and the aerobic lifestyle of model species belonging to three subphyla: Saccharomycotina (S. cerevisiae and C. albicans), Pezizomycotina (A. nidulans and N. crassa), and Taphrinomycotina (S. pombe). NEDD8/Rub1 is a key regulator of cellular redox homeostasis. Ascomycota species that produce mitochondria-derived ROS during glycolysis require NEDD8/Rub1for viability. NEDD8/Rub1 essentiality correlates with the existence of NEDP1 in the organism genome.
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Affiliation(s)
- Elah Pick
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon, 3600600, Israel.
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10
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Bailly AP, Perrin A, Serrano-Macia M, Maghames C, Leidecker O, Trauchessec H, Martinez-Chantar ML, Gartner A, Xirodimas DP. The Balance between Mono- and NEDD8-Chains Controlled by NEDP1 upon DNA Damage Is a Regulatory Module of the HSP70 ATPase Activity. Cell Rep 2020; 29:212-224.e8. [PMID: 31577950 PMCID: PMC6899524 DOI: 10.1016/j.celrep.2019.08.070] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/27/2019] [Accepted: 08/22/2019] [Indexed: 12/11/2022] Open
Abstract
Ubiquitin and ubiquitin-like chains are finely balanced by conjugating and de-conjugating enzymes. Alterations in this balance trigger the response to stress conditions and are often observed in pathologies. How such changes are detected is not well understood. We identify the HSP70 chaperone as a sensor of changes in the balance between mono- and poly-NEDDylation. Upon DNA damage, the induction of the de-NEDDylating enzyme NEDP1 restricts the formation of NEDD8 chains, mainly through lysines K11/K48. This promotes APAF1 oligomerization and apoptosis induction, a step that requires the HSP70 ATPase activity. HSP70 binds to NEDD8, and, in vitro, the conversion of NEDD8 chains into mono-NEDD8 stimulates HSP70 ATPase activity. This effect is independent of NEDD8 conjugation onto substrates. The study indicates that the NEDD8 cycle is a regulatory module of HSP70 function. These findings may be important in tumorigenesis, as we find decreased NEDP1 levels in hepatocellular carcinoma with concomitant accumulation of NEDD8 conjugates. Restriction of NEDD8 chains by NEDP1 is required for DNA damage-induced apoptosis The HSP70 chaperone is a sensor of the balance between mono- and NEDD8 chains Mono-NEDD8 stimulates HSP70 activity, which allows the formation of the apoptosome NEDP1 levels are downregulated in mouse hepatocellular carcinoma
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Affiliation(s)
- Aymeric P Bailly
- CRBM, CNRS, Univ. Montpellier, UMR5237, Montpellier 34090, Cedex 5, France.
| | - Aurelien Perrin
- CRBM, CNRS, Univ. Montpellier, UMR5237, Montpellier 34090, Cedex 5, France
| | - Marina Serrano-Macia
- Liver Disease Laboratory, CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 48160 Derio, Bizkaia, Spain
| | - Chantal Maghames
- CRBM, CNRS, Univ. Montpellier, UMR5237, Montpellier 34090, Cedex 5, France
| | - Orsolya Leidecker
- CRBM, CNRS, Univ. Montpellier, UMR5237, Montpellier 34090, Cedex 5, France
| | - Helene Trauchessec
- CRBM, CNRS, Univ. Montpellier, UMR5237, Montpellier 34090, Cedex 5, France
| | - M L Martinez-Chantar
- Liver Disease Laboratory, CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 48160 Derio, Bizkaia, Spain
| | - Anton Gartner
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
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11
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The COP9 Signalosome: A Multi-DUB Complex. Biomolecules 2020; 10:biom10071082. [PMID: 32708147 PMCID: PMC7407660 DOI: 10.3390/biom10071082] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/07/2020] [Accepted: 07/13/2020] [Indexed: 02/07/2023] Open
Abstract
The COP9 signalosome (CSN) is a signaling platform controlling the cellular ubiquitylation status. It determines the activity and remodeling of ~700 cullin-RING ubiquitin ligases (CRLs), which control more than 20% of all ubiquitylation events in cells and thereby influence virtually any cellular pathway. In addition, it is associated with deubiquitylating enzymes (DUBs) protecting CRLs from autoubiquitylation and rescuing ubiquitylated proteins from degradation. The coordination of ubiquitylation and deubiquitylation by the CSN is presumably important for fine-tuning the precise formation of defined ubiquitin chains. Considering its intrinsic DUB activity specific for deneddylation of CRLs and belonging to the JAMM family as well as its associated DUBs, the CSN represents a multi-DUB complex. Two CSN-associated DUBs, the ubiquitin-specific protease 15 (USP15) and USP48 are regulators in the NF-κB signaling pathway. USP15 protects CRL1β-TrCP responsible for IκBα ubiquitylation, whereas USP48 stabilizes the nuclear pool of the NF-κB transcription factor RelA upon TNF stimulation by counteracting CRL2SOCS1. Moreover, the CSN controls the neddylation status of cells by its intrinsic DUB activity and by destabilizing the associated deneddylation enzyme 1 (DEN1). Thus, the CSN is a master regulator at the intersection between ubiquitylation and neddylation.
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12
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Sahu MS, Patra S, Kumar K, Kaur R. SUMOylation in Human Pathogenic Fungi: Role in Physiology and Virulence. J Fungi (Basel) 2020; 6:E32. [PMID: 32143470 PMCID: PMC7096222 DOI: 10.3390/jof6010032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 02/07/2023] Open
Abstract
The small ubiquitin-related modifier (SUMO) protein is an important component of the post-translational protein modification systems in eukaryotic cells. It is known to modify hundreds of proteins involved in diverse cellular processes, ranging from nuclear pore dynamics to signal transduction pathways. Owing to its reversible nature, the SUMO-conjugation of proteins (SUMOylation) holds a prominent place among mechanisms that regulate the functions of a wide array of cellular proteins. The dysfunctional SUMOylation system has been associated with many human diseases, including neurodegenerative and autoimmune disorders. Furthermore, the non-pathogenic yeast Saccharomyces cerevisiae has served as an excellent model to advance our understanding of enzymes involved in SUMOylation and proteins modified by SUMOylation. Taking advantage of the tools and knowledge obtained from the S. cerevisiae SUMOylation system, research on fungal SUMOylation is beginning to gather pace, and new insights into the role of SUMOylation in the pathobiology of medically important fungi are emerging. Here, we summarize the known information on components of the SUMOylation machinery, and consequences of overexpression or deletion of these components in the human pathogenic fungi, with major focus on two prevalent Candida bloodstream pathogens, C. albicans and C. glabrata. Additionally, we have identified SUMOylation components, through in silico analysis, in four medically relevant fungi, and compared their sequence similarity with S. cerevisiae counterparts. SUMOylation modulates the virulence of C. albicans and C. glabrata, while it is required for conidia production in Aspergillus nidulans and A. flavus. In addition to highlighting these recent developments, we discuss how SUMOylation fine tunes the expression of virulence factors, and influences survival of fungal cells under diverse stresses in vitro and in the mammalian host.
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Affiliation(s)
- Mahima Sagar Sahu
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India; (M.S.S.); (S.P.); (K.K.)
- Graduate studies, Regional Centre for Biotechnology, Faridabad 121001, Haryana, India
| | - Sandip Patra
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India; (M.S.S.); (S.P.); (K.K.)
- Graduate studies, Regional Centre for Biotechnology, Faridabad 121001, Haryana, India
| | - Kundan Kumar
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India; (M.S.S.); (S.P.); (K.K.)
- Graduate studies, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Rupinder Kaur
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India; (M.S.S.); (S.P.); (K.K.)
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Sinha A, Israeli R, Cirigliano A, Gihaz S, Trabelcy B, Braus GH, Gerchman Y, Fishman A, Negri R, Rinaldi T, Pick E. The COP9 signalosome mediates the Spt23 regulated fatty acid desaturation and ergosterol biosynthesis. FASEB J 2020; 34:4870-4889. [PMID: 32077151 DOI: 10.1096/fj.201902487r] [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: 10/01/2019] [Revised: 01/02/2020] [Accepted: 01/14/2020] [Indexed: 02/06/2023]
Abstract
The COP9 signalosome (CSN) is a conserved eukaryotic complex, essential for vitality in all multicellular organisms and critical for the turnover of key cellular proteins through catalytic and non-catalytic activities. Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of the CSN complex, since it includes a conserved enzymatic core but lacks non-catalytic activities, probably explaining its non-essentiality for life. A previous transcriptomic analysis of an S. cerevisiae strain deleted in the CSN5/RRI1 gene, encoding to the CSN catalytic subunit, revealed a downregulation of genes involved in lipid metabolism. We now show that the S. cerevisiae CSN holocomplex is essential for cellular lipid homeostasis. Defects in CSN assembly or activity lead to decreased quantities of ergosterol and unsaturated fatty acids (UFA); vacuole defects; diminished lipid droplets (LDs) size; and to accumulation of endoplasmic reticulum (ER) stress. The molecular mechanism behind these findings depends on CSN involvement in upregulating mRNA expression of SPT23. Spt23 is a novel activator of lipid desaturation and ergosterol biosynthesis. Our data reveal for the first time a functional link between the CSN holocomplex and Spt23. Moreover, CSN-dependent upregulation of SPT23 transcription is necessary for the fine-tuning of lipid homeostasis and for cellular health.
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Affiliation(s)
- Abhishek Sinha
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Ran Israeli
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Angela Cirigliano
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Shalev Gihaz
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Beny Trabelcy
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Yoram Gerchman
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Ayelet Fishman
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Rodolfo Negri
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Teresa Rinaldi
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Elah Pick
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
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COP9 Signalosome Interaction with UspA/Usp15 Deubiquitinase Controls VeA-Mediated Fungal Multicellular Development. Biomolecules 2019; 9:biom9060238. [PMID: 31216760 PMCID: PMC6627422 DOI: 10.3390/biom9060238] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 06/02/2019] [Accepted: 06/16/2019] [Indexed: 12/26/2022] Open
Abstract
COP9 signalosome (CSN) and Den1/A deneddylases physically interact and promote multicellular development in fungi. CSN recognizes Skp1/cullin-1/Fbx E3 cullin-RING ligases (CRLs) without substrate and removes their posttranslational Nedd8 modification from the cullin scaffold. This results in CRL complex disassembly and allows Skp1 adaptor/Fbx receptor exchange for altered substrate specificity. We characterized the novel ubiquitin-specific protease UspA of the mold Aspergillusnidulans, which corresponds to CSN-associated human Usp15 and interacts with six CSN subunits. UspA reduces amounts of ubiquitinated proteins during fungal development, and the uspA gene expression is repressed by an intact CSN. UspA is localized in proximity to nuclei and recruits proteins related to nuclear transport and transcriptional processing, suggesting functions in nuclear entry control. UspA accelerates the formation of asexual conidiospores, sexual development, and supports the repression of secondary metabolite clusters as the derivative of benzaldehyde (dba) genes. UspA reduces protein levels of the fungal NF-kappa B-like velvet domain protein VeA, which coordinates differentiation and secondary metabolism. VeA stability depends on the Fbx23 receptor, which is required for light controlled development. Our data suggest that the interplay between CSN deneddylase, UspA deubiquitinase, and SCF-Fbx23 ensures accurate levels of VeA to support fungal development and an appropriate secondary metabolism.
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Riquelme M, Aguirre J, Bartnicki-García S, Braus GH, Feldbrügge M, Fleig U, Hansberg W, Herrera-Estrella A, Kämper J, Kück U, Mouriño-Pérez RR, Takeshita N, Fischer R. Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures. Microbiol Mol Biol Rev 2018; 82:e00068-17. [PMID: 29643171 PMCID: PMC5968459 DOI: 10.1128/mmbr.00068-17] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Filamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established.
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Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Jesús Aguirre
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Salomon Bartnicki-García
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics and Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Ursula Fleig
- Institute for Functional Genomics of Microorganisms, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Wilhelm Hansberg
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Jörg Kämper
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Ulrich Kück
- Ruhr University Bochum, Lehrstuhl für Allgemeine und Molekulare Botanik, Bochum, Germany
| | - Rosa R Mouriño-Pérez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Norio Takeshita
- University of Tsukuba, Faculty of Life and Environmental Sciences, Tsukuba, Japan
| | - Reinhard Fischer
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
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16
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Sem1 links proteasome stability and specificity to multicellular development. PLoS Genet 2018; 14:e1007141. [PMID: 29401458 PMCID: PMC5821377 DOI: 10.1371/journal.pgen.1007141] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 02/21/2018] [Accepted: 12/01/2017] [Indexed: 12/18/2022] Open
Abstract
The transition from vegetative growth to multicellular development represents an evolutionary hallmark linked to an oxidative stress signal and controlled protein degradation. We identified the Sem1 proteasome subunit, which connects stress response and cellular differentiation. The sem1 gene encodes the fungal counterpart of the human Sem1 proteasome lid subunit and is essential for fungal cell differentiation and development. A sem1 deletion strain of the filamentous fungus Aspergillus nidulans is able to grow vegetatively and expresses an elevated degree of 20S proteasomes with multiplied ATP-independent catalytic activity compared to wildtype. Oxidative stress induces increased transcription of the genes sem1 and rpn11 for the proteasomal deubiquitinating enzyme. Sem1 is required for stabilization of the Rpn11 deubiquitinating enzyme, incorporation of the ubiquitin receptor Rpn10 into the 19S regulatory particle and efficient 26S proteasome assembly. Sem1 maintains high cellular NADH levels, controls mitochondria integrity during stress and developmental transition. The cellular ubiquitin-proteasome pathway is essential to control cell cycle, gene expression or the response to oxidative stress. Sem1 is conserved in eukaryotes from single cell yeasts to humans as intrinsically disordered and multifunctional protein. Sem1 supports the assembly of several multiprotein complexes but becomes eventually exclusively a subunit of the lid of the 26S proteasome, a cellular machine with a molecular mass of about two megadalton. Defects in the function of the proteasome, which degrades a large fraction of intracellular proteins, result in cancer or neurodegenerative diseases. We showed that Sem1 from a multicellular fungus is required for accurate 26S proteasome assembly and specific activity as prerequisites for mitochondria integrity, oxidative stress response and cell differentiation. Our findings of the complex and dynamic interplay between multiple cellular processes mediated by a small conserved intrinsically unordered protein sheds light and supports current efforts to understand and explore in more details potential therapies to eventually treat age-related human diseases.
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Yu Y, Amich J, Will C, Eagle CE, Dyer PS, Krappmann S. The novel Aspergillus fumigatus MAT1-2-4 mating-type gene is required for mating and cleistothecia formation. Fungal Genet Biol 2017; 108:1-12. [PMID: 28889020 DOI: 10.1016/j.fgb.2017.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 08/28/2017] [Accepted: 09/01/2017] [Indexed: 10/18/2022]
Abstract
Sexual propagation accompanied by recombination and the formation of spore-containing fruiting bodies is a cornerstone of fungal genetics and biology. In the human pathogen Aspergillus fumigatus sexual identity has previously been shown to be determined by MAT1-1-1 or MAT1-2-1 genes which act as transcriptional regulators and are present within idiomorphs found at the MAT locus. We here report the identification and first characterization of a further novel gene, termed MAT1-2-4, that is present in the MAT1-2 idiomorph of A. fumigatus. A mating-type swapping strategy was used to achieve an unbiased deletion of the MAT1-2-4 gene with no impact on MAT1-2-1 gene expression. Phenotypical characterization of the resulting strain revealed an inability to mate with the compatible MAT1-1 progenitor, demonstrating that the MAT1-2-4 gene product is a genuine mating-type factor required for correct sexual development. A GPI-anchored protein of unknown function was identified as interaction partner. However, no functional role in the mating process or ascosporogenesis could be demonstrated by deletion analysis for this latter protein, although a role in heterokaryon formation is suggested. Bioinformatic analysis also demonstrated the presence of MAT1-2-4 homologues in some, but not all, other Aspergillus species and the evolutionary origins and implications of the MAT1-2-4 gene are discussed.
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Affiliation(s)
- Yidong Yu
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
| | - Jorge Amich
- Research Center for Infectious Diseases, Julius-Maximilians-Universität Würzburg, Germany
| | - Cornelia Will
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
| | - Carly E Eagle
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Paul S Dyer
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Sven Krappmann
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany.
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18
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Zheng Y, Wang X, Zhang X, Li W, Liu G, Wang S, Yan X, Zou H, Yin WB. COP9 signalosome subunit PfCsnE regulates secondary metabolism and conidial formation in Pestalotiopsis fici. SCIENCE CHINA-LIFE SCIENCES 2017; 60:656-664. [PMID: 28550524 DOI: 10.1007/s11427-017-9068-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/06/2017] [Indexed: 12/19/2022]
Abstract
The COP9 signalosome (CSN) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. In filamentous fungi, several lines of evidence indicate that fungal development and secondary metabolism (SM) are mediated by the fifth subunit of CSN, called CsnE. Here we uncover a connection with CsnE and conidial formation as well as SM regulation in the plant endophytic fungus Pestalotiopsis fici. A homology search of the P. fici genome with CsnE, involved in sexual development and SM in Aspergillus nidulans, identified PfCsnE. Deletion of PfcsnE resulted in a mutant that stopped conidial production, but the conidia are recovered in a PfcsnE complemented strain. This indicates that PfCsnE is required for the formation of conidia. Secondary metabolite analysis demonstrated that the ΔPfcsnE strain produced more chloroisosulochrin, less ficiolide A production in comparison to wild type (WT). Transcriptome analysis of WT and ΔPfcsnE strains indicated that PfcsnE impacts the expression levels of 8.37% of 14,797 annotated genes. Specifically, nine biosynthetic gene clusters (BGCs) were up-regulated and three BGCs were down-regulated by PfCsnE. Our results suggest that PfCsnE plays major roles in SM regulation and conidial development in P. fici.
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Affiliation(s)
- Yanjing Zheng
- Zhejiang Provincial (Wenzhou) Key Lab for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiuna Wang
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xiaoling Zhang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wei Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Gang Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shihua Wang
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xiufeng Yan
- Zhejiang Provincial (Wenzhou) Key Lab for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Huixi Zou
- Zhejiang Provincial (Wenzhou) Key Lab for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.
| | - Wen-Bing Yin
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Cul3 neddylation is crucial for gradual lipid droplet formation during adipogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1405-1412. [PMID: 28499918 DOI: 10.1016/j.bbamcr.2017.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 05/08/2017] [Indexed: 01/04/2023]
Abstract
Cullin 3 (Cul3) belongs to the family of cullins (Cul1-7) providing the scaffold for cullin-RING ubiquitin (Ub) ligases (CRLs), which are activated by neddylation and represent essential E3 ligases of the Ub proteasome system. During adipogenic differentiation neddylated Cul3 accumulates in LiSa-2 preadipocytes. Downregulation of Cul3 and inhibition of neddylation by MLN4924 blocks the formation of lipid droplets (LDs), the lipid storage organelles and markers of adipogenesis. Neddylation of Cul3 coincides with an increase of Rab18, a GTPase associated with LDs. Immunoprecipitation and confocal fluorescence microscopy revealed physical association of Cul3 and Rab18 at the membrane of LDs. RhoA, a suppressor of adipogenesis decreased during differentiation. Our results in LiSa-2 cells, but also mouse embryonic fibroblasts revealed a connection between Cul3, Rab18 and RhoA. Downregulation of Cul3 led to a marked increase in RhoA protein expression after 6days of LiSa-2 cell differentiation, suggesting that Cul3 is involved in the regulation of RhoA stability.
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20
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Mergner J, Kuster B, Schwechheimer C. DENEDDYLASE1 Protein Counters Automodification of Neddylating Enzymes to Maintain NEDD8 Protein Homeostasis in Arabidopsis. J Biol Chem 2017; 292:3854-3865. [PMID: 28096463 DOI: 10.1074/jbc.m116.767103] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 01/10/2017] [Indexed: 11/06/2022] Open
Abstract
In eukaryotes, the conjugation of the ubiquitin-like protein NEDD8 onto protein targets is an important post-translational modification. The best understood neddylation targets are the cullins, scaffold subunits of E3 ubiquitin ligases, where neddylation as well as deneddylation, facilitated by the protease activity of the CSN (COP9 signalosome), are required to control ubiquitin ligase assembly, function, and ultimately substrate degradation. Little is known about the role of other deneddylating enzymes besides CSN and the role of neddylation and deneddylation of their substrates. We previously characterized Arabidopsis thaliana mutants with defects in the conserved NEDD8-specific protease DEN1 (DENEDDYLASE1). These mutants display only subtle growth phenotypes despite the strong accumulation of a broad range of neddylated proteins. Specifically, we identified AXR1 (AUXIN-RESISTANT1), a subunit of the heterodimeric NAE (E1 NEDD8-ACTIVATING ENZYME), as highly neddylated in den1 mutants. Here, we examined the mechanism and consequences of AXR1 neddylation in more detail. We find that AXR1 as well as other neddylation enzymes are autoneddylated at multiple lysines. NAE autoneddylation can be linked to reduced NCE (E2 NEDD8-CONJUGATING ENZYME) NEDD8 thioester levels, either by critically reducing the pool of free NEDD8 or by reducing NAE activity. In planta, increasing NEDD8 gene dosage is sufficient to suppress den1 mutant phenotypes. We therefore suggest that DEN1 serves to recover diverted NEDD8 moieties from autoneddylated NAE subunits, and possibly also other neddylated proteins, to maintain NEDD8 pathway activity toward other NEDD8-dependent processes such as cullin E3 ligase regulation.
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Affiliation(s)
- Julia Mergner
- From the Chair of Plant Systems Biology, Technische Universität München, Emil-Ramann-Strasse 8 and.,the Chair of Proteomics and Bioanalytics, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Bernhard Kuster
- the Chair of Proteomics and Bioanalytics, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Claus Schwechheimer
- From the Chair of Plant Systems Biology, Technische Universität München, Emil-Ramann-Strasse 8 and
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Wicker CA, Izumi T. Analysis of RNA expression of normal and cancer tissues reveals high correlation of COP9 gene expression with respiratory chain complex components. BMC Genomics 2016; 17:983. [PMID: 27903243 PMCID: PMC5131501 DOI: 10.1186/s12864-016-3313-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 11/18/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The COP9 signalosome, composed of eight subunits, is implicated in cancer genetics with its deneddylase activity to modulate cellular concentration of oncogenic proteins such as IkB and TGFβ. However, its function in the normal cell physiology remains elusive. Primarily focusing on gene expression data of the normal tissues of the head and neck, the cancer genome atlas (TCGA) database was used to identify groups of genes that were expressed synergistically with the COP9 genes, particularly with the COPS5 (CSN5), which possesses the catalytic activity of COP9. RESULTS Expressions of seven of the COP9 genes (COPS2, COPS3, COPS4, COPS5, COPS6, COPS7A, and COPS8) were found to be highly synergistic in the normal tissues. In contrast, the tumor tissues decreased the coordinated expression pattern of COP9 genes. Pathway analysis revealed a high coordination of the expression of the COPS5 and the other COP9 genes with mitochondria-related functional pathways, including genes encoding the respiratory chain complex. CONCLUSIONS The results indicate that mRNA expression data for the matched normal tissues available in TCGA are statistically reliable, and are highly useful to assess novel associations of genes with functional pathways in normal physiology as well as in the cancer tissues. This study revealed the significant correlation between the expressions of the COP9 genes and those related to the mitochondrial activity.
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Affiliation(s)
- Christina A Wicker
- Department of Toxicology and Cancer Biology, University of Kentucky, 1095 V.A. Dr, Lexington, KY, 40536, USA
| | - Tadahide Izumi
- Department of Toxicology and Cancer Biology, University of Kentucky, 1095 V.A. Dr, Lexington, KY, 40536, USA.
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Meister C, Gulko MK, Köhler AM, Braus GH. The devil is in the details: comparison between COP9 signalosome (CSN) and the LID of the 26S proteasome. Curr Genet 2016; 62:129-36. [PMID: 26497135 DOI: 10.1007/s00294-015-0525-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 10/05/2015] [Accepted: 10/06/2015] [Indexed: 01/29/2023]
Abstract
The COP9 signalosome (CSN) and the proteasomal LID are conserved macromolecular complexes composed of at least eight subunits with molecular weights of approximately 350 kDa. CSN and LID are part of the ubiquitin–proteasome pathway and cleave isopeptide linkages of lysine side chains on target proteins. CSN cleaves the isopeptide bond of ubiquitin-like protein Nedd8 from cullins, whereas the LID cleaves ubiquitin from target proteins sentenced for degradation. CSN and LID are structurally and functionally similar but the order of the assembly pathway seems to be different. The assembly differs in at least the last subunit joining the pre-assembled subcomplex. This review addresses the similarities and differences in structure, function and assembly of CSN and LID.
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23
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Jöhnk B, Bayram Ö, Abelmann A, Heinekamp T, Mattern DJ, Brakhage AA, Jacobsen ID, Valerius O, Braus GH. SCF Ubiquitin Ligase F-box Protein Fbx15 Controls Nuclear Co-repressor Localization, Stress Response and Virulence of the Human Pathogen Aspergillus fumigatus. PLoS Pathog 2016; 12:e1005899. [PMID: 27649508 PMCID: PMC5029927 DOI: 10.1371/journal.ppat.1005899] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 08/26/2016] [Indexed: 01/27/2023] Open
Abstract
F-box proteins share the F-box domain to connect substrates of E3 SCF ubiquitin RING ligases through the adaptor Skp1/A to Cul1/A scaffolds. F-box protein Fbx15 is part of the general stress response of the human pathogenic mold Aspergillus fumigatus. Oxidative stress induces a transient peak of fbx15 expression, resulting in 3x elevated Fbx15 protein levels. During non-stress conditions Fbx15 is phosphorylated and F-box mediated interaction with SkpA preferentially happens in smaller subpopulations in the cytoplasm. The F-box of Fbx15 is required for an appropriate oxidative stress response, which results in rapid dephosphorylation of Fbx15 and a shift of the cellular interaction with SkpA to the nucleus. Fbx15 binds SsnF/Ssn6 as part of the RcoA/Tup1-SsnF/Ssn6 co-repressor and is required for its correct nuclear localization. Dephosphorylated Fbx15 prevents SsnF/Ssn6 nuclear localization and results in the derepression of gliotoxin gene expression. fbx15 deletion mutants are unable to infect immunocompromised mice in a model for invasive aspergillosis. Fbx15 has a novel dual molecular function by controlling transcriptional repression and being part of SCF E3 ubiquitin ligases, which is essential for stress response, gliotoxin production and virulence in the opportunistic human pathogen A. fumigatus. The opportunistic human fungal pathogen Aspergillus fumigatus is the most prevalent cause for severe fungal infections in immunocompromised hosts. A major virulence factor of A. fumigatus is its ability to rapidly adapt to host conditions during infection. The rapid response to environmental changes underlies a well-balanced system of production and degradation of proteins. The degradation of specific target proteins is mediated by ubiquitin-protein ligases (E3), which mark their target proteins with ubiquitin for proteasomal degradation. Multisubunit SCF Cullin1 Ring ligases (CRL) are E3 ligases where the F-box subunit functions as a substrate-specificity determining adaptor. A comprehensive control of protein production includes global co-repressors as the conserved Ssn6(SsnF)-Tup1(RcoA) complex, which reduces transcription on multiple levels. We have identified a novel connection between protein degradation and synthesis through an F-box protein. Fbx15 can be incorporated into SCF E3 ubiquitin ligases and controls upon stress the nuclear localization of the SsnF. Fbx15 plays a critical role for A. fumigatus adaptation and is essential for virulence in a murine infection model. Fbx15 is a fungal-specific protein and therefore a potential target for future drug development.
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Affiliation(s)
- Bastian Jöhnk
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, Göttingen, Germany
| | - Özgür Bayram
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, Göttingen, Germany
- Department of Biology, Maynooth University, National University of Ireland, Maynooth, County Kildare, Ireland
| | - Anja Abelmann
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, Göttingen, Germany
| | - Thorsten Heinekamp
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Friedrich Schiller University, Jena, Germany
| | - Derek J. Mattern
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Friedrich Schiller University, Jena, Germany
| | - Axel A. Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Friedrich Schiller University, Jena, Germany
| | - Ilse D. Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Friedrich Schiller University, Jena, Germany
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, Göttingen, Germany
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University, Göttingen, Germany
- * E-mail:
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Barth E, Hübler R, Baniahmad A, Marz M. The Evolution of COP9 Signalosome in Unicellular and Multicellular Organisms. Genome Biol Evol 2016; 8:1279-89. [PMID: 27044515 PMCID: PMC4860701 DOI: 10.1093/gbe/evw073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The COP9 signalosome (CSN) is a highly conserved protein complex, recently being crystallized for human. In mammals and plants the COP9 complex consists of nine subunits, CSN 1–8 and CSNAP. The CSN regulates the activity of culling ring E3 ubiquitin and plays central roles in pleiotropy, cell cycle, and defense of pathogens. Despite the interesting and essential functions, a thorough analysis of the CSN subunits in evolutionary comparative perspective is missing. Here we compared 61 eukaryotic genomes including plants, animals, and yeasts genomes and show that the most conserved subunits of eukaryotes among the nine subunits are CSN2 and CSN5. This may indicate a strong evolutionary selection for these two subunits. Despite the strong conservation of the protein sequence, the genomic structures of the intron/exon boundaries indicate no conservation at genomic level. This suggests that the gene structure is exposed to a much less selection compared with the protein sequence. We also show the conservation of important active domains, such as PCI (proteasome lid-CSN-initiation factor) and MPN (MPR1/PAD1 amino-terminal). We identified novel exons and alternative splicing variants for all CSN subunits. This indicates another level of complexity of the CSN. Notably, most COP9-subunits were identified in all multicellular and unicellular eukaryotic organisms analyzed, but not in prokaryotes or archaeas. Thus, genes encoding CSN subunits present in all analyzed eukaryotes indicate the invention of the signalosome at the root of eukaryotes. The identification of alternative splice variants indicates possible “mini-complexes” or COP9 complexes with independent subunits containing potentially novel and not yet identified functions.
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Affiliation(s)
- Emanuel Barth
- Bioinformatics/High Throughput Analysis, Friedrich Schiller University, Jena, Germany FLI Leibniz Institute for Age Research, Jena, Germany
| | - Ron Hübler
- Bioinformatics/High Throughput Analysis, Friedrich Schiller University, Jena, Germany Institute of Human Genetics, Jena University Hospital, Jena, Germany Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI), Jena, Germany
| | - Aria Baniahmad
- Institute of Human Genetics, Jena University Hospital, Jena, Germany
| | - Manja Marz
- Bioinformatics/High Throughput Analysis, Friedrich Schiller University, Jena, Germany FLI Leibniz Institute for Age Research, Jena, Germany
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Schinke J, Kolog Gulko M, Christmann M, Valerius O, Stumpf SK, Stirz M, Braus GH. The DenA/DEN1 Interacting Phosphatase DipA Controls Septa Positioning and Phosphorylation-Dependent Stability of Cytoplasmatic DenA/DEN1 during Fungal Development. PLoS Genet 2016; 12:e1005949. [PMID: 27010942 PMCID: PMC4806917 DOI: 10.1371/journal.pgen.1005949] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 03/01/2016] [Indexed: 11/18/2022] Open
Abstract
DenA/DEN1 and the COP9 signalosome (CSN) represent two deneddylases which remove the ubiquitin-like Nedd8 from modified target proteins and are required for distinct fungal developmental programmes. The cellular DenA/DEN1 population is divided into a nuclear and a cytoplasmatic subpopulation which is especially enriched at septa. DenA/DEN1 stability control mechanisms are different for the two cellular subpopulations and depend on different physical interacting proteins and the C-terminal DenA/DEN1 phosphorylation pattern. Nuclear DenA/DEN1 is destabilized during fungal development by five of the eight CSN subunits which target nuclear DenA/DEN1 for degradation. DenA/DEN1 becomes stabilized as a phosphoprotein at S243/S245 during vegetative growth, which is necessary to support further asexual development. After the initial phase of development, the newly identified cytoplasmatic DenA/DEN1 interacting phosphatase DipA and an additional developmental specific C-terminal phosphorylation site at serine S253 destabilize DenA/DEN1. Outside of the nucleus, DipA is co-transported with DenA/DEN1 in the cytoplasm between septa and nuclei. Deletion of dipA resulted in increased DenA/DEN1 stability in a strain which is unresponsive to illumination. The mutant strain is dysregulated in cytokinesis and impaired in asexual development. Our results suggest a dual phosphorylation-dependent DenA/DEN1 stability control with stabilizing and destabilizing modifications and physical interaction partner proteins which function as control points in the nucleus and the cytoplasm.
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Affiliation(s)
- Josua Schinke
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Miriam Kolog Gulko
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Martin Christmann
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Sina Kristin Stumpf
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Margarita Stirz
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences (GZMB), and Georg-August-University, Göttingen, Germany
- * E-mail:
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27
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Chung D, Dellaire G. The Role of the COP9 Signalosome and Neddylation in DNA Damage Signaling and Repair. Biomolecules 2015; 5:2388-416. [PMID: 26437438 PMCID: PMC4693240 DOI: 10.3390/biom5042388] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/18/2015] [Accepted: 09/21/2015] [Indexed: 01/28/2023] Open
Abstract
The maintenance of genomic integrity is an important process in organisms as failure to sense and repair damaged DNA can result in a variety of diseases. Eukaryotic cells have developed complex DNA repair response (DDR) mechanisms to accurately sense and repair damaged DNA. Post-translational modifications by ubiquitin and ubiquitin-like proteins, such as SUMO and NEDD8, have roles in coordinating the progression of DDR. Proteins in the neddylation pathway have also been linked to regulating DDR. Of interest is the COP9 signalosome (CSN), a multi-subunit metalloprotease present in eukaryotes that removes NEDD8 from cullins and regulates the activity of cullin-RING ubiquitin ligases (CRLs). This in turn regulates the stability and turnover of a host of CRL-targeted proteins, some of which have established roles in DDR. This review will summarize the current knowledge on the role of the CSN and neddylation in DNA repair.
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Affiliation(s)
- Dudley Chung
- Department of Pathology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Graham Dellaire
- Department of Pathology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
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Dubiel D, Rockel B, Naumann M, Dubiel W. Diversity of COP9 signalosome structures and functional consequences. FEBS Lett 2015; 589:2507-13. [PMID: 26096786 DOI: 10.1016/j.febslet.2015.06.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 06/09/2015] [Accepted: 06/09/2015] [Indexed: 01/01/2023]
Abstract
The COP9 signalosome (CSN) is a regulator of the ubiquitin (Ub) proteasome system (UPS). It interacts with hundreds of cullin-RING ubiquitin E3 ligases (CRLs) and regulates their activity by removing the Ub-like protein Nedd8 from cullins. In mammalian cells 7 different cullins exist which form CRLs with adaptor proteins and with a large number of substrate recognition subunits such as F-box and BTB proteins. This large variety of CRL-complexes is deneddylated by the CSN. The capacity of the CSN to interact with numerous types of CRL complexes can be explained by its structural diversity, which allows different CSN variants to interact with different binding partners and substrates and enables different subunit expression profiles. Diversity of CSN complexes presumably occurs by: (1) flexibility of CSN holo complex structure; (2) formation of CSN mini complexes and free CSN subunits and (3) generation of CSN variants via integration of CSN subunit isoforms. In this review we will discuss the structural diversity of the CSN complex and possible functional consequences.
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Affiliation(s)
- Dawadschargal Dubiel
- Institute of Experimental Internal Medicine, Medical Faculty, Otto von Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Beate Rockel
- Department of Molecular Structural Biology, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany
| | - Michael Naumann
- Institute of Experimental Internal Medicine, Medical Faculty, Otto von Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Wolfgang Dubiel
- Department of General, Visceral, Vascular and Thoracic Surgery, Division of Molecular Biology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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Beckmann EA, Köhler AM, Meister C, Christmann M, Draht OW, Rakebrandt N, Valerius O, Braus GH. Integration of the catalytic subunit activates deneddylase activity in vivo as final step in fungal COP9 signalosome assembly. Mol Microbiol 2015; 97:110-24. [PMID: 25846252 DOI: 10.1111/mmi.13017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2015] [Indexed: 12/23/2022]
Abstract
The eight-subunit COP9 signalosome (CSN) is conserved from filamentous fungi to humans and functions at the interface between cellular signalling and protein half-life control. CSN consists of six PCI and two MPN domain proteins and forms a scaffold for additional interacting proteins. CSN controls protein stability in the ubiquitin-proteasome system where the MPN domain CSN5/CsnE subunit inactivates cullin-RING ligases. The CSN5/CsnE isopeptidase functions as deneddylase and removes the ubiquitin-like protein Nedd8. The six PCI domain proteins of human CSN form a horseshoe-like ring and all eight subunits are connected by a bundle of C-terminal α-helices. We show that single deletions of any csn subunit of Aspergillus nidulans resulted in the lack of deneddylase activity and identical defects in the coordination of development and secondary metabolism. The CSN1/CsnA N-terminus is dispensable for deneddylase activity but required for asexual spore formation. Complex analyses in mutant strains revealed the presence of a seven-subunit pre-CSN without catalytic activity. Reconstitution experiments with crude extracts of deletion strains and recombinant proteins allowed the integration of CSN5/CsnE into pre-CSN resulting in an active deneddylase. This supports a stable seven subunit pre-CSN intermediate where deneddylase activation in vivo can be controlled by CSN5/CsnE integration as final assembly step.
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Affiliation(s)
- Elena A Beckmann
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Anna M Köhler
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Cindy Meister
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Martin Christmann
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Oliver W Draht
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Nikolas Rakebrandt
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Oliver Valerius
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
| | - Gerhard H Braus
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
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Mergner J, Heinzlmeir S, Kuster B, Schwechheimer C. DENEDDYLASE1 deconjugates NEDD8 from non-cullin protein substrates in Arabidopsis thaliana. THE PLANT CELL 2015; 27:741-53. [PMID: 25783028 PMCID: PMC4558671 DOI: 10.1105/tpc.114.135996] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/05/2015] [Accepted: 02/26/2015] [Indexed: 05/25/2023]
Abstract
The evolutionarily conserved 8-kD protein NEDD8 (NEURAL PRECURSOR CELL EXPRESSED, DEVELOPMENTALLY DOWN-REGULATED8) belongs to the family of ubiquitin-like modifiers. Like ubiquitin, NEDD8 is conjugated to and deconjugated from target proteins. Many targets and functions of ubiquitylation have been described; by contrast, few targets of NEDD8 have been identified. In plants as well as in non-plant organisms, the cullin subunits of cullin-RING E3 ligases are NEDD8 conjugates with a demonstrated functional role for the NEDD8 modification. The existence of other non-cullin NEDD8 targets has generally been questioned. NEDD8 is translated as a precursor protein and proteolytic processing exposes a C-terminal glycine required for NEDD8 conjugation. In animals and yeast, DENEDDYLASE1 (DEN1) processes NEDD8. Here, we show that mutants of a DEN1 homolog from Arabidopsis thaliana have no detectable defects in NEDD8 processing but do accumulate a broad range of NEDD8 conjugates; this provides direct evidence for the existence of non-cullin NEDD8 conjugates. We further identify AUXIN RESISTANT1 (AXR1), a subunit of the heterodimeric NEDD8 E1 activating enzyme, as a NEDD8-modified protein in den1 mutants and wild type and provide evidence that AXR1 function may be compromised in the absence of DEN1 activity. Thus, in plants, neddylation may serve as a regulatory mechanism for cullin and non-cullin proteins.
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Affiliation(s)
- Julia Mergner
- Plant Systems Biology, Technische Universität München, 85354 Freising, Germany Proteomics and Bioanalytics, Technische Universität München, 85354 Freising, Germany
| | - Stephanie Heinzlmeir
- Proteomics and Bioanalytics, Technische Universität München, 85354 Freising, Germany
| | - Bernhard Kuster
- Proteomics and Bioanalytics, Technische Universität München, 85354 Freising, Germany
| | - Claus Schwechheimer
- Plant Systems Biology, Technische Universität München, 85354 Freising, Germany
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Kandala S, Kim IM, Su H. Neddylation and deneddylation in cardiac biology. AMERICAN JOURNAL OF CARDIOVASCULAR DISEASE 2014; 4:140-158. [PMID: 25628956 PMCID: PMC4299693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 12/23/2014] [Indexed: 06/04/2023]
Abstract
Neddylation is a post-translational protein modification that conjugates a ubiquitin-like protein NEDD8 to target proteins. Similar to ubiquitination, neddylation is mediated by a cascade of three NEDD8 specific enzymes, an E1 activating enzyme, an E2 conjugating enzyme and one of the several E3 ligases. Neddylation is countered by the action of deneddylases via a process termed deneddylation. By altering the substrate's conformation, stability, subcellular localization or binding affinity to DNA or proteins, neddylation regulates diverse cellular processes including the ubiquitin-proteasome system-mediated protein degradation, protein transcription, cell signaling etc. Dysregulation of neddylation has been linked to cancer, neurodegenerative disorders, and more recently, cardiac disease. Here we comprehensively overview the biochemistry, the proteome and the biological function of neddylation. We also summarize the recent progress in revealing the physiological and pathological role of neddylation and deneddylation in the heart.
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Affiliation(s)
- Sridhar Kandala
- Vascular Biology Center, Medical College of Georgia, Georgia Regents UniversityAugusta, GA, USA
| | - Il-man Kim
- Vascular Biology Center, Medical College of Georgia, Georgia Regents UniversityAugusta, GA, USA
| | - Huabo Su
- Vascular Biology Center, Medical College of Georgia, Georgia Regents UniversityAugusta, GA, USA
- Department of Pharmacology and Toxicology, Medical College of Georgia, Georgia Regents UniversityAugusta, GA, USA
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Gerke J, Braus GH. Manipulation of fungal development as source of novel secondary metabolites for biotechnology. Appl Microbiol Biotechnol 2014; 98:8443-55. [PMID: 25142695 PMCID: PMC4192562 DOI: 10.1007/s00253-014-5997-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 07/25/2014] [Accepted: 07/28/2014] [Indexed: 12/19/2022]
Abstract
Fungal genomics revealed a large potential of yet-unexplored secondary metabolites, which are not produced during vegetative growth. The discovery of novel bioactive compounds is increasingly gaining importance. The high number of resistances against established antibiotics requires novel drugs to counteract increasing human and animal mortality rates. In addition, growth of plant pathogens has to be controlled to minimize harvest losses. An additional critical issue is the post-harvest production of deleterious mycotoxins. Fungal development and secondary metabolite production are linked processes. Therefore, molecular regulators of development might be suitable to discover new bioactive fungal molecules or to serve as targets to control fungal growth, development, or secondary metabolite production. The fungal impact is relevant as well for our healthcare systems as for agriculture. We propose here to use the knowledge about mutant strains discovered in fungal model systems for a broader application to detect and explore new fungal drugs or toxins. As examples, mutant strains impaired in two conserved eukaryotic regulatory complexes are discussed. The COP9 signalosome (CSN) and the velvet complex act at the interface between development and secondary metabolism. The CSN is a multi-protein complex of up to eight subunits and controls the activation of CULLIN-RING E3 ubiquitin ligases, which mark substrates with ubiquitin chains for protein degradation by the proteasome. The nuclear velvet complex consists of the velvet-domain proteins VeA and VelB and the putative methyltransferase LaeA acting as a global regulator for secondary metabolism. Defects in both complexes disturb fungal development, light perception, and the control of secondary metabolism. The potential biotechnological relevance of these developmental fungal mutant strains for drug discovery, agriculture, food safety, and human healthcare is discussed.
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Affiliation(s)
- Jennifer Gerke
- Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Gerhard H. Braus
- Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, D-37077 Göttingen, Germany
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Rockel B, Schmaler T, Huang X, Dubiel W. Electron microscopy and in vitro deneddylation reveal similar architectures and biochemistry of isolated human and Flag-mouse COP9 signalosome complexes. Biochem Biophys Res Commun 2014; 450:991-7. [PMID: 24973710 DOI: 10.1016/j.bbrc.2014.06.093] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 06/18/2014] [Indexed: 11/29/2022]
Abstract
The COP9 signalosome (CSN) is a regulator of the ubiquitin (Ub) proteasome system (UPS). In the UPS, proteins are Ub-labeled for degradation by Ub ligases conferring substrate specificity. The CSN controls a large family of Ub ligases called cullin-RING ligases (CRLs), which ubiquitinate cell cycle regulators, transcription factors and DNA damage response proteins. The CSN possesses structural similarities with the 26S proteasome Lid complex and the translation initiation complex 3 (eIF3) indicating similar ancestry and function. Initial structures were obtained 14years ago by 2D electron microscopy (EM). Recently, first 3D molecular models of the CSN were created on the basis of negative-stain EM and single-particle analysis, mostly with recombinant complexes. Here, we compare deneddylating activity and structural features of CSN complexes purified in an elaborate procedure from human erythrocytes and efficiently pulled down from mouse Flag-CSN2 B8 fibroblasts. In an in vitro deneddylation assay both the human and the mouse CSN complexes deneddylated Nedd8-Cul1 with comparable rates. 3D structural models of the erythrocyte CSN as well as of the mouse Flag-CSN were generated by negative stain EM and by cryo-EM. Both complexes show a central U-shaped segment from which several arms emanate. This structure, called the horseshoe, is formed by the PCI domain subunits. CSN5 and CSN6 point away from the horseshoe. Compared to 3D models of negatively stained CSN complexes, densities assigned to CSN2 and CSN4 are better defined in the cryo-map. Because biochemical and structural results obtained with CSN complexes isolated from human erythrocytes and purified by Flag-CSN pulldown from mouse B8 fibroblasts are very similar, Flag-CSN pulldowns are a proper alternative to CSN preparation from erythrocytes.
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Affiliation(s)
- Beate Rockel
- Department of Molecular Structural Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Tilo Schmaler
- Division of Molecular Biology, Department of General, Visceral, Vascular and Thoracic Surgery, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Xiaohua Huang
- Division of Molecular Biology, Department of General, Visceral, Vascular and Thoracic Surgery, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Wolfgang Dubiel
- Division of Molecular Biology, Department of General, Visceral, Vascular and Thoracic Surgery, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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Mergner J, Schwechheimer C. The NEDD8 modification pathway in plants. FRONTIERS IN PLANT SCIENCE 2014; 5:103. [PMID: 24711811 PMCID: PMC3968751 DOI: 10.3389/fpls.2014.00103] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Accepted: 03/03/2014] [Indexed: 05/19/2023]
Abstract
NEDD8, in plants and yeasts also known as RELATED TO UBIQUITIN (RUB), is an evolutionarily conserved 76 amino acid protein highly related to ubiquitin. Like ubiquitin, NEDD8 can be conjugated to and deconjugated from target proteins, but unlike ubiquitin, NEDD8 has not been reported to form chains similar to the different polymeric ubiquitin chains that have a role in a diverse set of cellular processes. NEDD8-modification is best known as a post-translational modification of the cullin subunits of cullin-RING E3 ubiquitin ligases. In this context, structural analyses have revealed that neddylation induces a conformation change of the cullin that brings the ubiquitylation substrates into proximity of the interacting E2 conjugating enzyme. In turn, NEDD8 deconjugation destabilizes the cullin RING ligase complex allowing for the exchange of substrate recognition subunits via the exchange factor CAND1. In plants, components of the neddylation and deneddylation pathway were identified based on mutants with defects in auxin and light responses and the characterization of these mutants has been instrumental for the elucidation of the neddylation pathway. More recently, there has been evidence from animal and plant systems that NEDD8 conjugation may also regulate the behavior or fate of non-cullin substrates in a number of ways. Here, the current knowledge on NEDD8 processing, conjugation and deconjugation is presented, where applicable, in the context of specific signaling pathways from plants.
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Affiliation(s)
| | - Claus Schwechheimer
- *Correspondence: Claus Schwechheimer, Plant Systems Biology, Technische Universität München, Emil-Ramann-Straße 4, 85354 Freising, Germany e-mail:
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Ahmed YL, Gerke J, Park HS, Bayram Ö, Neumann P, Ni M, Dickmanns A, Kim SC, Yu JH, Braus GH, Ficner R. The velvet family of fungal regulators contains a DNA-binding domain structurally similar to NF-κB. PLoS Biol 2013; 11:e1001750. [PMID: 24391470 PMCID: PMC3876986 DOI: 10.1371/journal.pbio.1001750] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 11/18/2013] [Indexed: 12/20/2022] Open
Abstract
This study reveals an important family of fungal regulatory proteins to be transcription factors that contain a DNA-binding “velvet” domain structurally related to that of mammalian NFkB. Morphological development of fungi and their combined production of secondary metabolites are both acting in defence and protection. These processes are mainly coordinated by velvet regulators, which contain a yet functionally and structurally uncharacterized velvet domain. Here we demonstrate that the velvet domain of VosA is a novel DNA-binding motif that specifically recognizes an 11-nucleotide consensus sequence consisting of two motifs in the promoters of key developmental regulatory genes. The crystal structure analysis of the VosA velvet domain revealed an unforeseen structural similarity with the Rel homology domain (RHD) of the mammalian transcription factor NF-κB. Based on this structural similarity several conserved amino acid residues present in all velvet domains have been identified and shown to be essential for the DNA binding ability of VosA. The velvet domain is also involved in dimer formation as seen in the solved crystal structures of the VosA homodimer and the VosA-VelB heterodimer. These findings suggest that defence mechanisms of both fungi and animals might be governed by structurally related DNA-binding transcription factors. In many fungi, developmental processes and the synthesis of nonessential chemicals (secondary metabolites) are regulated by various external stimuli, such as light. Although fungi employ them for defensive purposes, secondary metabolites range from useful antibiotics to powerful toxins, so understanding the molecular processes that regulate their synthesis is of particular interest to us. In the mold Aspergillus nidulans the main regulators of these processes are the so-called “velvet” proteins VeA, VelB, and VosA, which share a 150-amino acid region known as the velvet domain. Velvet proteins interact with each other, alone (“homodimers”), in various combinations (“heterodimers”), and also with other proteins, but the molecular mechanism by which these proteins exert their regulatory function has been unclear. In this work we show that velvet proteins form a family of fungus-specific transcription factors that directly bind to target DNA, even though analysis of their amino acid sequence does not reveal any known DNA-binding domains or motifs. We determined the three-dimensional structure of the VosA-VosA homodimer and the VosA-VelB heterodimer and found that the structure of the velvet domain is strongly reminiscent of the N-terminal immunoglobulin-like domain found in the mammalian transcription factor NFκB-p50, despite the very low sequence similarity. We propose that, like NFκB, various homo- or heterodimers of velvet proteins modulate gene expression to drive development and defensive pathways in fungi.
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MESH Headings
- Aspergillus nidulans/genetics
- Aspergillus nidulans/physiology
- Consensus Sequence/genetics
- Consensus Sequence/physiology
- DNA, Fungal/genetics
- DNA, Fungal/physiology
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/physiology
- Gene Expression Regulation, Developmental/genetics
- Gene Expression Regulation, Developmental/physiology
- Gene Expression Regulation, Fungal/genetics
- Gene Expression Regulation, Fungal/physiology
- Genes, Fungal/genetics
- Genes, Fungal/physiology
- Genes, rel/genetics
- Genes, rel/physiology
- NF-kappa B/genetics
- NF-kappa B/physiology
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Affiliation(s)
- Yasar Luqman Ahmed
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Jennifer Gerke
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Hee-Soo Park
- Departments of Bacteriology and Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Özgür Bayram
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Piotr Neumann
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Min Ni
- Departments of Bacteriology and Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Achim Dickmanns
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Sun Chang Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Dae-Jon, Republic of Korea
| | - Jae-Hyuk Yu
- Departments of Bacteriology and Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- * E-mail: (J.-H.Y.); (G.H.B.); (R.F.)
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
- * E-mail: (J.-H.Y.); (G.H.B.); (R.F.)
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
- * E-mail: (J.-H.Y.); (G.H.B.); (R.F.)
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Harting R, Bayram O, Laubinger K, Valerius O, Braus GH. Interplay of the fungal sumoylation network for control of multicellular development. Mol Microbiol 2013; 90:1125-45. [PMID: 24279728 DOI: 10.1111/mmi.12421] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2013] [Indexed: 12/30/2022]
Abstract
The role of the complex network of the ubiquitin-like modifier SumO in fungal development was analysed. SumO is not only required for sexual development but also for accurate induction and light stimulation of asexual development. The Aspergillus nidulans COMPASS complex including its subunits CclA and the methyltransferase SetA connects the SumO network to histone modification. SetA is required for correct positioning of aerial hyphae for conidiophore and asexual spore formation. Multicellular fungal development requires sumoylation and desumoylation. This includes the SumO processing enzyme UlpB, the E1 SumO activating enzyme AosA/UbaB, the E2 conjugation enzyme UbcN and UlpA as major SumO isopeptidase. Genetic suppression analysis suggests a connection between the genes for the Nedd8 isopeptidase DenA and the SumO isopeptidase UlpA and therefore a developmental interplay between neddylation and sumoylation in fungi. Biochemical evidence suggests an additional connection of the fungal SumO network with ubiquitination. Members of the cellular SumO network include histone modifiers, components of the transcription, RNA maturation and stress response machinery, or metabolic enzymes. Our data suggest that the SumO network controls specific temporal and spatial steps in fungal differentiation.
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Affiliation(s)
- Rebekka Harting
- Institut für Mikrobiologie und Genetik, Georg-August Universität Göttingen, Grisebachstrasse 8, D-37077, Göttingen, Germany
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Suzuki S, Sarikaya Bayram Ö, Bayram Ö, Braus GH. conF and conJ contribute to conidia germination and stress response in the filamentous fungus Aspergillus nidulans. Fungal Genet Biol 2013; 56:42-53. [PMID: 23644150 DOI: 10.1016/j.fgb.2013.04.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 04/08/2013] [Accepted: 04/10/2013] [Indexed: 01/08/2023]
Abstract
Light induces various responses in fungi including formation of asexual and sexual reproductive structures. The formation of conidia in the filamentous fungus Aspergillus nidulans is regulated by red and blue light receptors. Expression of conidia associated con genes, which are widely spread in the fungal kingdom, increases upon exposure to light. We have characterized the light-inducible conF and conJ genes of A. nidulans which are homologs of con-6 and con-10 of Neurospora crassa. con genes are expressed during conidia formation in asexual development. Five minutes light exposure are sufficient to induce conF or conJ expression in vegetative mycelia. Similar to N. crassa there were no significant phenotypes of single con mutations. A double conF and conJ deletion resulted in significantly increased cellular amounts of glycerol or erythritol. This leads to a delayed germination phenotype combined with increased resistance against desiccation. These defects were rescued by complementation of the double mutant strain with either conF or conJ. This suggests that fungal con genes exhibit redundant functions in controlling conidia germination and adjusting cellular levels of substances which protect conidia against dryness.
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Affiliation(s)
- Satoshi Suzuki
- Institute of Microbiology and Genetics, Department of Molecular Microbiology and Genetics, Georg August University, Grisebachstr. 8, 37077 Göttingen, Germany
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