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Strawn G, Wong RWK, Young BP, Davey M, Nislow C, Conibear E, Loewen CJR, Mayor T. Genome-wide screen identifies new set of genes for improved heterologous laccase expression in Saccharomyces cerevisiae. Microb Cell Fact 2024; 23:36. [PMID: 38287338 PMCID: PMC10823697 DOI: 10.1186/s12934-024-02298-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 01/04/2024] [Indexed: 01/31/2024] Open
Abstract
The yeast Saccharomyces cerevisiae is widely used as a host cell for recombinant protein production due to its fast growth, cost-effective culturing, and ability to secrete large and complex proteins. However, one major drawback is the relatively low yield of produced proteins compared to other host systems. To address this issue, we developed an overlay assay to screen the yeast knockout collection and identify mutants that enhance recombinant protein production, specifically focusing on the secretion of the Trametes trogii fungal laccase enzyme. Gene ontology analysis of these mutants revealed an enrichment of processes including vacuolar targeting, vesicle trafficking, proteolysis, and glycolipid metabolism. We confirmed that a significant portion of these mutants also showed increased activity of the secreted laccase when grown in liquid culture. Notably, we found that the combination of deletions of OCA6, a tyrosine phosphatase gene, along with PMT1 or PMT2, two genes encoding ER membrane protein-O-mannosyltransferases involved in ER quality control, and SKI3, which encode for a component of the SKI complex responsible for mRNA degradation, further increased secreted laccase activity. Conversely, we also identified over 200 gene deletions that resulted in decreased secreted laccase activity, including many genes that encode for mitochondrial proteins and components of the ER-associated degradation pathway. Intriguingly, the deletion of the ER DNAJ co-chaperone gene SCJ1 led to almost no secreted laccase activity. When we expressed SCJ1 from a low-copy plasmid, laccase secretion was restored. However, overexpression of SCJ1 had a detrimental effect, indicating that precise dosing of key chaperone proteins is crucial for optimal recombinant protein expression. This study offers potential strategies for enhancing the overall yield of recombinant proteins and provides new avenues for further research in optimizing protein production systems.
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Affiliation(s)
- Garrett Strawn
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Ryan W K Wong
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Barry P Young
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Michael Davey
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Corey Nislow
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Elizabeth Conibear
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Christopher J R Loewen
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Thibault Mayor
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada.
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2
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He X, Guo X, Du Z, Liu X, Jing J, Zhou C, Cheng Y, Wang Z, He XP. Enhancement of Intracellular Accumulation of Copper by Biogenesis of Lipid Droplets in Saccharomyces cerevisiae Revealed by Transcriptomic Analysis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:7170-7179. [PMID: 35657321 DOI: 10.1021/acs.jafc.2c01071] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Copper is an essential micronutrient for life, whose homeostasis is rigorously regulated to meet the demands of normal biological processes and to minimize the potential toxicity. Copper enriched by yeast is regarded as a safe and bioavailable form of copper supplements. Here, a Saccharomyces cerevisiae mutant strain H247 with expanded storage capability of copper was obtained through atmospheric and room-temperature plasma treatment. Transcriptomic analyses found that transcriptional upregulation of DGA1 might be the major contributor to the enhancement of intracellular copper accumulation in strain H247. The positive correlation between biogenesis of lipid droplets and intracellular accumulation of copper was confirmed by overexpression of the diacylglycerol acyltransferase encoding genes DGA1 and LRO1 or knockout of DGA1. Lipid droplets are not only the storage pool of copper but might prompt the copper trafficking to mitochondria, vacuoles, and Golgi apparatus. These results provide new insights into the sophisticated copper homeostatic mechanisms and the biological functions of lipid droplets.
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Affiliation(s)
- Xiaoxian He
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, 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 100101, China
| | - Xuena Guo
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhengda Du
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, 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 100101, China
| | - Xuelian Liu
- State Key Laboratory of Direct-Fed Microbial Engineering, Beijing DaBeiNong Science and Technology Group Co., Ltd. (DBN), Beijing 100192, China
| | - Junnian Jing
- State Key Laboratory of Direct-Fed Microbial Engineering, Beijing DaBeiNong Science and Technology Group Co., Ltd. (DBN), Beijing 100192, China
| | - Chenyao Zhou
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, 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 100101, China
| | - Yanfei Cheng
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhaoyue Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiu-Ping He
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, 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 100101, China
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3
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Radchenko EA, Aksenova AY, Volkov KV, Shishkin AA, Pavlov YI, Mirkin SM. Partners in crime: Tbf1 and Vid22 promote expansions of long human telomeric repeats at an interstitial chromosome position in yeast. PNAS NEXUS 2022; 1:pgac080. [PMID: 35832866 PMCID: PMC9272169 DOI: 10.1093/pnasnexus/pgac080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 06/01/2022] [Indexed: 02/05/2023]
Abstract
In humans, telomeric repeats (TTAGGG)n are known to be present at internal chromosomal sites. These interstitial telomeric sequences (ITSs) are an important source of genomic instability, including repeat length polymorphism, but the molecular mechanisms responsible for this instability remain to be understood. Here, we studied the mechanisms responsible for expansions of human telomeric (Htel) repeats that were artificially inserted inside a yeast chromosome. We found that Htel repeats in an interstitial chromosome position are prone to expansions. The propensity of Htel repeats to expand depends on the presence of a complex of two yeast proteins: Tbf1 and Vid22. These two proteins are physically bound to an interstitial Htel repeat, and together they slow replication fork progression through it. We propose that slow progression of the replication fork through the protein complex formed by the Tbf1 and Vid22 partners at the Htel repeat cause DNA strand slippage, ultimately resulting in repeat expansions.
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Affiliation(s)
| | | | - Kirill V Volkov
- Laboratory of Amyloid Biology, St. Petersburg State University, St. Petersburg, 199034, Russia
| | | | - Youri I Pavlov
- Eppley Institute for Research In Cancer and Allied Diseases, Omaha, NE 68198, USA
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4
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Tirincsi A, Sicking M, Hadzibeganovic D, Haßdenteufel S, Lang S. The Molecular Biodiversity of Protein Targeting and Protein Transport Related to the Endoplasmic Reticulum. Int J Mol Sci 2021; 23:143. [PMID: 35008565 PMCID: PMC8745461 DOI: 10.3390/ijms23010143] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 12/15/2022] Open
Abstract
Looking at the variety of the thousands of different polypeptides that have been focused on in the research on the endoplasmic reticulum from the last five decades taught us one humble lesson: no one size fits all. Cells use an impressive array of components to enable the safe transport of protein cargo from the cytosolic ribosomes to the endoplasmic reticulum. Safety during the transit is warranted by the interplay of cytosolic chaperones, membrane receptors, and protein translocases that together form functional networks and serve as protein targeting and translocation routes. While two targeting routes to the endoplasmic reticulum, SRP (signal recognition particle) and GET (guided entry of tail-anchored proteins), prefer targeting determinants at the N- and C-terminus of the cargo polypeptide, respectively, the recently discovered SND (SRP-independent) route seems to preferentially cater for cargos with non-generic targeting signals that are less hydrophobic or more distant from the termini. With an emphasis on targeting routes and protein translocases, we will discuss those functional networks that drive efficient protein topogenesis and shed light on their redundant and dynamic nature in health and disease.
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Affiliation(s)
- Andrea Tirincsi
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Mark Sicking
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Drazena Hadzibeganovic
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Sarah Haßdenteufel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sven Lang
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
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5
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Ko HT, Hsu LH, Yang SY, Chen YL. Repurposing the thrombopoietin receptor agonist eltrombopag as an anticryptococcal agent. Med Mycol 2021; 58:493-504. [PMID: 31297540 DOI: 10.1093/mmy/myz077] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/14/2019] [Accepted: 06/18/2019] [Indexed: 01/02/2023] Open
Abstract
In this study, a Food and Drug Administration (FDA)-approved drug with previously unreported antifungal activity was investigated for suitability for use as an anticryptococcal agent. First, we screened a compound library of 1018 FDA-approved drugs against Cryptococcus neoformans. Of 52 drugs possessing anti-Cryptococcus activity, eltrombopag was chosen due to its novel activity. The susceptibility of Cryptococcus against eltrombopag was then studied by determining the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), while the synergy of eltrombopag with other drugs was tested by fractional inhibitory concentration index (FICI). Eltrombopag had a limited spectrum of antifungal activity against C. neoformans/C. gattii species complex (MICs of 0.125 mg/l), Candida glabrata (MIC, 0.25 mg/l), and Trichophyton rubrum (MIC, 0.5 mg/l). Eltrombopag affected cryptococcal virulence factors, including capsule and biofilm formation, melanin production, and growth ability at 37°C. Further, RNA sequencing and deletion mutant library screening experiments revealed that genes involved in the calcineurin pathway, lipid biosynthesis, membrane component, and transporter genes were associated with eltrombopag. In addition, eltrombopag showed synergism with the calcineurin inhibitor FK506 (FICI < 0.5) against Cryptococcus species. In conclusion, eltrombopag exhibited excellent antifungal activity against Cryptococcus species potentially via a mode of action which interferes with virulence factors and the calcineurin pathway, indicating that eltrombopag might be usefully repurposed as an antifungal agent for treating cryptococcosis.
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Affiliation(s)
- Hao-Tai Ko
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617 Taiwan.,Faculty of Medicine, Medical University of Lublin, Lublin, 20093 Poland
| | - Li-Hang Hsu
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617 Taiwan
| | - Sheng-Yung Yang
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617 Taiwan
| | - Ying-Lien Chen
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617 Taiwan
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6
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Manandhar SP, Siddiqah IM, Cocca SM, Gharakhanian E. A kinase cascade on the yeast lysosomal vacuole regulates its membrane dynamics: conserved kinase Env7 is phosphorylated by casein kinase Yck3. J Biol Chem 2020; 295:12262-12278. [PMID: 32647006 PMCID: PMC7443493 DOI: 10.1074/jbc.ra119.012346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 06/02/2020] [Indexed: 01/15/2023] Open
Abstract
Membrane fusion/fission is a highly dynamic and conserved process that responds to intra- and extracellular signals. Whereas the molecular machineries involved in membrane fusion/fission have been dissected, regulation of membrane dynamics remains poorly understood. The lysosomal vacuole of budding yeast (Saccharomyces cerevisiae) has served as a seminal model in studies of membrane dynamics. We have previously established that yeast ENV7 encodes an ortholog of STK16-related kinases that localizes to the vacuolar membrane and downregulates vacuolar membrane fusion. Additionally, we have previously reported that Env7 phosphorylation in vivo depends on YCK3, a gene that encodes a vacuolar membrane casein kinase I (CKI) homolog that nonredundantly functions in fusion regulation. Here, we report that Env7 physically interacts with and is directly phosphorylated by Yck3. We also establish that Env7 vacuole fusion/fission regulation and vacuolar localization are mediated through its Yck3-dependent phosphorylation. Through extensive site-directed mutagenesis, we map phosphorylation to the Env7 C terminus and confirm that Ser-331 is a primary and preferred phosphorylation site. Phospho-deficient Env7 mutants were defective in negative regulation of membrane fusion, increasing the number of prominent vacuoles, whereas a phosphomimetic substitution at Ser-331 increased the number of fragmented vacuoles. Bioinformatics approaches confirmed that Env7 Ser-331 is within a motif that is highly conserved in STK16-related kinases and that it also anchors an SXXS CKI phosphorylation motif (328SRFS331). This study represents the first report on the regulatory mechanism of an STK16-related kinase. It also points to regulation of vacuolar membrane dynamics via a novel Yck3-Env7 kinase cascade.
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Affiliation(s)
- Surya P Manandhar
- Department of Biological Sciences, California State University at Long Beach, Long Beach, California, USA
| | - Ikha M Siddiqah
- Department of Biological Sciences, California State University at Long Beach, Long Beach, California, USA
| | - Stephanie M Cocca
- Department of Biological Sciences, California State University at Long Beach, Long Beach, California, USA
| | - Editte Gharakhanian
- Department of Biological Sciences, California State University at Long Beach, Long Beach, California, USA.
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7
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Wang J, Ji X, Liu J, Zhang X. Serine/Threonine Protein Kinase STK16. Int J Mol Sci 2019; 20:ijms20071760. [PMID: 30974739 PMCID: PMC6480182 DOI: 10.3390/ijms20071760] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 04/05/2019] [Accepted: 04/08/2019] [Indexed: 12/18/2022] Open
Abstract
STK16 (Ser/Thr kinase 16, also known as Krct/PKL12/MPSK1/TSF-1) is a myristoylated and palmitoylated Ser/Thr protein kinase that is ubiquitously expressed and conserved among all eukaryotes. STK16 is distantly related to the other kinases and belongs to the NAK kinase family that has an atypical activation loop architecture. As a membrane-associated protein that is primarily localized to the Golgi, STK16 has been shown to participate in the TGF-β signaling pathway, TGN protein secretion and sorting, as well as cell cycle and Golgi assembly regulation. This review aims to provide a comprehensive summary of the progress made in recent research about STK16, ranging from its distribution, molecular characterization, post-translational modification (fatty acylation and phosphorylation), interactors (GlcNAcK/DRG1/MAL2/Actin/WDR1), and related functions. As a relatively underexplored kinase, more studies are encouraged to unravel its regulation mechanisms and cellular functions.
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Affiliation(s)
- Junjun Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China.
| | - Xinmiao Ji
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Juanjuan Liu
- School of Life Sciences, Anhui University, Hefei 230601, China.
| | - Xin Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China.
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
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8
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Siddiqah IM, Manandhar SP, Cocca SM, Hsueh T, Cervantes V, Gharakhanian E. Yeast ENV9 encodes a conserved lipid droplet (LD) short-chain dehydrogenase involved in LD morphology. Curr Genet 2017; 63:1053-1072. [PMID: 28540421 DOI: 10.1007/s00294-017-0702-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/24/2017] [Accepted: 05/05/2017] [Indexed: 12/31/2022]
Abstract
Lipid droplets (LDs) have emerged as dynamic and interactive organelles with important roles in lipid metabolism and membrane biogenesis. Here, we report that Saccharomyces cerevisiae Env9 is a novel conserved oxidoreductase involved in LD morphology. Microscopic and biochemical studies confirm localization of tagged Env9 to LDs and implicate its C-terminal hydrophobic domain (aa241-265) in its membrane association and stability. Confocal studies reveal a role for Env9 in LD morphology. Env9 positively affects both formation of large LDs upon overexpression and LD proliferation under poor carbon source. In silico bioinformatic and modeling approaches establish that ENV9 is a widely conserved member of the short-chain dehydrogenase (SDR) superfamily. Bayesian phylogenetic studies strongly support ENV9 as an ortholog of human SDR retinol dehydrogenase 12 (RDH12). Dehydrogenase activity of Env9 was confirmed by in vitro oxidoreductase assays. RDH12 mutations have been linked to Leber Congenital Amaurosis. Similar site-directed point mutations in the predicted Env9 oxidoreductase active site (N146L) or cofactor-binding site (G23-24A) abolished its reductase activity in vitro, consistent with those reported in other retinol dehydrogenases. The same residues were essential for affecting LD size and number in vivo. Taken together, our results implicate oxidoreductase activity of Env9 in its cellular role in LD morphology.
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Affiliation(s)
- Ikha M Siddiqah
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA
| | - Surya P Manandhar
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA
| | - Stephanie M Cocca
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA
| | - Teli Hsueh
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA
| | - Vanessa Cervantes
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA
| | - Editte Gharakhanian
- Department of Biological Sciences, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA, 90840, USA.
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9
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Aviram N, Ast T, Costa EA, Arakel EC, Chuartzman SG, Jan CH, Haßdenteufel S, Dudek J, Jung M, Schorr S, Zimmermann R, Schwappach B, Weissman JS, Schuldiner M. The SND proteins constitute an alternative targeting route to the endoplasmic reticulum. Nature 2017; 540:134-138. [PMID: 27905431 DOI: 10.1038/nature20169] [Citation(s) in RCA: 147] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 10/18/2016] [Indexed: 12/19/2022]
Abstract
In eukaryotes, up to one-third of cellular proteins are targeted to the endoplasmic reticulum, where they undergo folding, processing, sorting and trafficking to subsequent endomembrane compartments. Targeting to the endoplasmic reticulum has been shown to occur co-translationally by the signal recognition particle (SRP) pathway or post-translationally by the mammalian transmembrane recognition complex of 40 kDa (TRC40) and homologous yeast guided entry of tail-anchored proteins (GET) pathways. Despite the range of proteins that can be catered for by these two pathways, many proteins are still known to be independent of both SRP and GET, so there seems to be a critical need for an additional dedicated pathway for endoplasmic reticulum relay. We set out to uncover additional targeting proteins using unbiased high-content screening approaches. To this end, we performed a systematic visual screen using the yeast Saccharomyces cerevisiae, and uncovered three uncharacterized proteins whose loss affected targeting. We suggest that these proteins work together and demonstrate that they function in parallel with SRP and GET to target a broad range of substrates to the endoplasmic reticulum. The three proteins, which we name Snd1, Snd2 and Snd3 (for SRP-independent targeting), can synthetically compensate for the loss of both the SRP and GET pathways, and act as a backup targeting system. This explains why it has previously been difficult to demonstrate complete loss of targeting for some substrates. Our discovery thus puts in place an essential piece of the endoplasmic reticulum targeting puzzle, highlighting how the targeting apparatus of the eukaryotic cell is robust, interlinked and flexible.
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Affiliation(s)
- Naama Aviram
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Tslil Ast
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Elizabeth A Costa
- Department of Cellular and Molecular Pharmacology, UCSF California Institute for Quantitative Biomedical Research and Howard Hughes Medical Institute, San Francisco, California 94158-2330, USA
| | - Eric C Arakel
- Department of Molecular Biology, University Medical Center Göttingen, 37073 Göttingen, Germany
| | - Silvia G Chuartzman
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Calvin H Jan
- Department of Cellular and Molecular Pharmacology, UCSF California Institute for Quantitative Biomedical Research and Howard Hughes Medical Institute, San Francisco, California 94158-2330, USA
| | - Sarah Haßdenteufel
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany
| | - Johanna Dudek
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany
| | - Martin Jung
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany
| | - Stefan Schorr
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany
| | - Richard Zimmermann
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany
| | - Blanche Schwappach
- Department of Molecular Biology, University Medical Center Göttingen, 37073 Göttingen, Germany.,Max-Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, UCSF California Institute for Quantitative Biomedical Research and Howard Hughes Medical Institute, San Francisco, California 94158-2330, USA
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
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10
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Mattiazzi Ušaj M, Prelec M, Brložnik M, Primo C, Curk T, Ščančar J, Yenush L, Petrovič U. Yeast Saccharomyces cerevisiae adiponectin receptor homolog Izh2 is involved in the regulation of zinc, phospholipid and pH homeostasis. Metallomics 2016; 7:1338-51. [PMID: 26067383 DOI: 10.1039/c5mt00095e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The functional link between zinc homeostasis and membrane-related processes, including lipid metabolism regulation, extends from yeast to humans, and has a likely role in the pathogenesis of diabetes. The yeast Izh2 protein has been previously implicated in zinc ion homeostasis and in the regulation of lipid and phosphate metabolism, but its precise molecular function is not known. We performed a chemogenomics experiment to determine the genes conferring resistance or sensitivity to different environmental zinc concentrations. We then determined at normal, depleted and excess zinc concentrations, the genetic interactions of IZH2 at the genome-wide level and measured changes in the transcriptome caused by deletion of IZH2. We found evidence for an important cellular function of the Rim101 pathway in zinc homeostasis in neutral or acidic environments, and observed that phosphatidylinositol is a source of inositol when zinc availability is limited. Comparison of our experimental profiles with published gene expression and genetic interaction profiles revealed pleiotropic functions for Izh2. We propose that Izh2 acts as an integrator of intra- and extracellular signals in providing adequate cellular responses to maintain homeostasis under different external conditions, including - but not limited to - alterations in zinc concentrations.
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Affiliation(s)
- Mojca Mattiazzi Ušaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
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11
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Ianiri G, Idnurm A, Castoria R. Transcriptomic responses of the basidiomycete yeast Sporobolomyces sp. to the mycotoxin patulin. BMC Genomics 2016; 17:210. [PMID: 26956724 PMCID: PMC4784387 DOI: 10.1186/s12864-016-2550-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 02/28/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Patulin is a mycotoxin produced by Penicillium expansum, the causal agent of blue mold of stored pome fruits, and several other species of filamentous fungi. This mycotoxin has genotoxic, teratogenic and immunotoxic effects in mammals, and its presence in pome fruits and derived products represents a serious health hazard. Biocontrol agents in the Pucciniomycotina, such as the yeasts Sporobolomyces sp. strain IAM 13481 and Rhodosporidium kratochvilovae strain LS11, are able to resist patulin and degrade it into the less toxic compounds desoxypatulinic acid and ascladiol. RESULTS In this investigation we applied a transcriptomic approach based on RNAseq to annotate the genome of Sporobolomyces sp. IAM 13481 and then study the changes of gene expression in Sporobolomyces sp. exposed to patulin. Patulin treatment leads to ROS production and oxidative stress that result in the activation of stress response mechanisms controlled by transcription factors. Upregulated Sporobolomyces genes were those involved in oxidation-reduction and transport processes, suggesting the activation of defense mechanisms to resist patulin toxicity and expel the mycotoxin out of the cells. Other upregulated genes encoded proteins involved in metabolic processes such as those of the glutathione and thioredoxin systems, which are essential to restore the cellular redox homeostasis. Conversely, patulin treatment decreased the expression of genes involved in the processes of protein synthesis and modification, such as transcription, RNA processing, translation, protein phosphorylation and biosynthesis of amino acids. Also, genes encoding proteins involved in transport of ions, cell division and cell cycle were downregulated. This indicates a reduction of metabolic activity, probably due to the high energy requirement by the cells or metabolic arrest while recovering from the insult caused by patulin toxicity. CONCLUSIONS Complex mechanisms are activated in a biocontrol yeast in response to patulin. The genes identified in this study can pave the way to develop i) a biodetoxification process of patulin in juices and ii) a biosensor for the rapid and cost-effective detection of this mycotoxin.
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Affiliation(s)
- Giuseppe Ianiri
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via F. De Sanctis snc, 86100, Campobasso, Italy.
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO, 64110, USA.
- Present address: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Alexander Idnurm
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO, 64110, USA.
- School of BioSciences, University of Melbourne, Melbourne, VIC, 3010, Australia.
| | - Raffaello Castoria
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via F. De Sanctis snc, 86100, Campobasso, Italy.
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12
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Wells ML, Washington OL, Hicks SN, Nobile CJ, Hartooni N, Wilson GM, Zucconi BE, Huang W, Li L, Fargo DC, Blackshear PJ. Post-transcriptional regulation of transcript abundance by a conserved member of the tristetraprolin family in Candida albicans. Mol Microbiol 2015; 95:1036-53. [PMID: 25524641 DOI: 10.1111/mmi.12913] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2014] [Indexed: 11/29/2022]
Abstract
Members of the tristetraprolin (TTP) family of CCCH tandem zinc finger proteins bind to AU-rich regions in target mRNAs, leading to their deadenylation and decay. Family members in Saccharomyces cerevisiae influence iron metabolism, whereas the single protein expressed in Schizosaccharomyces pombe, Zfs1, regulates cell-cell interactions. In the human pathogen Candida albicans, deep sequencing of mutants lacking the orthologous protein, Zfs1, revealed significant increases (> 1.5-fold) in 156 transcripts. Of these, 113 (72%) contained at least one predicted TTP family member binding site in their 3'UTR, compared with only 3 of 56 (5%) down-regulated transcripts. The zfs1Δ/Δ mutant was resistant to 3-amino-1,2,4-triazole, perhaps because of increased expression of the potential target transcript encoded by HIS3. Sequences of the proteins encoded by the putative Zfs1 targets were highly conserved among other species within the fungal CTG clade, while the predicted Zfs1 binding sites in these mRNAs often 'disappeared' with increasing evolutionary distance from the parental species. C. albicans Zfs1 bound to the ideal mammalian TTP binding site with high affinity, and Zfs1 was associated with target transcripts after co-immunoprecipitation. Thus, the biochemical activities of these proteins in fungi are highly conserved, but Zfs1-like proteins may target different transcripts in each species.
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Affiliation(s)
- Melissa L Wells
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, Research Triangle Park, NC, 27709, USA
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13
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Jin K, Musso G, Vlasblom J, Jessulat M, Deineko V, Negroni J, Mosca R, Malty R, Nguyen-Tran DH, Aoki H, Minic Z, Freywald T, Phanse S, Xiang Q, Freywald A, Aloy P, Zhang Z, Babu M. Yeast Mitochondrial Protein–Protein Interactions Reveal Diverse Complexes and Disease-Relevant Functional Relationships. J Proteome Res 2015; 14:1220-37. [DOI: 10.1021/pr501148q] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ke Jin
- Terrence
Donnelly Centre, University of Toronto, Toronto, Ontario M5S 3E1, Canada
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Gabriel Musso
- Cardiovascular
Division, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department
of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - James Vlasblom
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Matthew Jessulat
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Viktor Deineko
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Jacopo Negroni
- Joint
IRB−BSC Program in Computational Biology, IRB, Barcelona 08028, Spain
| | - Roberto Mosca
- Joint
IRB−BSC Program in Computational Biology, IRB, Barcelona 08028, Spain
| | - Ramy Malty
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Diem-Hang Nguyen-Tran
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Hiroyuki Aoki
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Zoran Minic
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Tanya Freywald
- Cancer Research
Unit, Saskatchewan Cancer Agency, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Sadhna Phanse
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Qian Xiang
- Terrence
Donnelly Centre, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Andrew Freywald
- Cancer Research
Unit, Saskatchewan Cancer Agency, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Patrick Aloy
- Joint
IRB−BSC Program in Computational Biology, IRB, Barcelona 08028, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain
| | - Zhaolei Zhang
- Terrence
Donnelly Centre, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Mohan Babu
- Department
of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
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14
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Cohen BE. Functional linkage between genes that regulate osmotic stress responses and multidrug resistance transporters: challenges and opportunities for antibiotic discovery. Antimicrob Agents Chemother 2013; 58:640-6. [PMID: 24295980 PMCID: PMC3910827 DOI: 10.1128/aac.02095-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
All cells need to protect themselves against the osmotic challenges of their environment by maintaining low permeability to ions across their cell membranes. This is a basic principle of cellular function, which is reflected in the interactions among ion transport and drug efflux genes that have arisen during cellular evolution. Thus, upon exposure to pore-forming antibiotics such as amphotericin B (AmB) or daptomycin (Dap), sensitive cells overexpress common resistance genes to protect themselves from added osmotic challenges. These genes share pathway interactions with the various types of multidrug resistance (MDR) transporter genes, which both preserve the native lipid membrane composition and at the same time eliminate disruptive hydrophobic molecules that partition excessively within the lipid bilayer. An increased understanding of the relationships between the genes (and their products) that regulate osmotic stress responses and MDR transporters will help to identify novel strategies and targets to overcome the current stalemate in drug discovery.
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Affiliation(s)
- B Eleazar Cohen
- National Institute of Allergy and Infectious Diseases, Division of Extramural Activities, Bethesda, Maryland, USA
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15
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Ma M, Han P, Zhang R, Li H. Ultrastructural changes of Saccharomyces cerevisiae in response to ethanol stress. Can J Microbiol 2013; 59:589-97. [PMID: 24011341 DOI: 10.1139/cjm-2012-0745] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In the fermentative process using Saccharomyces cerevisiae to produce bioethanol, the performance of cells is often compromised by the accumulation of ethanol. However, the mechanism of how S. cerevisiae responds against ethanol stress remains elusive. In the current study, S. cerevisiae cells were cultured in YPD (yeast extract - peptone - dextrose) medium containing various concentrations of ethanol (0%, 2.5%, 5%, 7.5%, 10%, and 15% (v/v)). Compared with the control group without ethanol, the mean cell volume of S. cerevisiae decreased significantly in the presence of 7.5% and 10% ethanol after incubation for 16 h (P < 0.05), and in the presence of 15% ethanol at all 3 sampling time points (1, 8, and 16 h) (P < 0.05). The exposure of S. cerevisiae cells to ethanol also led to an increase in malonyldialdehyde content (P < 0.05) and a decrease in sulfhydryl group content (P < 0.05). Moreover, the observations through transmission electron microscopy enabled us to relate ultrastructural changes elicited by ethanol with the cellular stress physiology. Under ethanol stress, the integrity of the cell membrane was compromised. The swelling or distortion of mitochondria together with the occurrence of a single and large vacuole was correlated with the addition of ethanol. These results suggested that the cell membrane is one of the targets of ethanol, and the degeneration of mitochondria promoted the accumulation of intracellular reactive oxygen species.
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Affiliation(s)
- Manli Ma
- College of Life Science and Technology, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, People's Republic of China
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16
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Sauer M, Delgadillo MO, Zouhar J, Reynolds GD, Pennington JG, Jiang L, Liljegren SJ, Stierhof YD, De Jaeger G, Otegui MS, Bednarek SY, Rojo E. MTV1 and MTV4 encode plant-specific ENTH and ARF GAP proteins that mediate clathrin-dependent trafficking of vacuolar cargo from the trans-Golgi network. THE PLANT CELL 2013; 25:2217-35. [PMID: 23771894 PMCID: PMC3723622 DOI: 10.1105/tpc.113.111724] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/14/2013] [Accepted: 05/30/2013] [Indexed: 05/18/2023]
Abstract
Many soluble proteins transit through the trans-Golgi network (TGN) and the prevacuolar compartment (PVC) en route to the vacuole, but our mechanistic understanding of this vectorial trafficking step in plants is limited. In particular, it is unknown whether clathrin-coated vesicles (CCVs) participate in this transport step. Through a screen for modified transport to the vacuole (mtv) mutants that secrete the vacuolar protein VAC2, we identified MTV1, which encodes an epsin N-terminal homology protein, and MTV4, which encodes the ADP ribosylation factor GTPase-activating protein nevershed/AGD5. MTV1 and NEV/AGD5 have overlapping expression patterns and interact genetically to transport vacuolar cargo and promote plant growth, but they have no apparent roles in protein secretion or endocytosis. MTV1 and NEV/AGD5 colocalize with clathrin at the TGN and are incorporated into CCVs. Importantly, mtv1 nev/agd5 double mutants show altered subcellular distribution of CCV cargo exported from the TGN. Moreover, MTV1 binds clathrin in vitro, and NEV/AGD5 associates in vivo with clathrin, directly linking these proteins to CCV formation. These results indicate that MTV1 and NEV/AGD5 are key effectors for CCV-mediated trafficking of vacuolar proteins from the TGN to the PVC in plants.
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Affiliation(s)
- Michael Sauer
- Departamento Molecular de Plantas, Centro Nacional de Biotecnología (Consejo Superior de Investigaciones Cientificas), 28049 Madrid, Spain
| | - M. Otilia Delgadillo
- Departamento Molecular de Plantas, Centro Nacional de Biotecnología (Consejo Superior de Investigaciones Cientificas), 28049 Madrid, Spain
| | - Jan Zouhar
- Departamento Molecular de Plantas, Centro Nacional de Biotecnología (Consejo Superior de Investigaciones Cientificas), 28049 Madrid, Spain
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica, 28223 Madrid, Spain
| | | | | | - Liwen Jiang
- School of Life Sciences, Centre for Cell and Developmental Biology, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Sarah J. Liljegren
- Department of Biology, University of Mississippi, Oxford, Mississippi 38677-1848
| | - York-Dieter Stierhof
- Zentrum für Molekularbiologie der Pflanzen, University of Tübingen, 72076 Tuebingen, Germany
| | - Geert De Jaeger
- Department of Plant Systems Biology, VIB, B-9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium
| | - Marisa S. Otegui
- Department of Botany, University of Madison, Madison, Wisconsin 53706
| | | | - Enrique Rojo
- Departamento Molecular de Plantas, Centro Nacional de Biotecnología (Consejo Superior de Investigaciones Cientificas), 28049 Madrid, Spain
- Address correspondence to
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17
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Rodrigues J, Silva RD, Noronha H, Pedras A, Gerós H, Côrte-Real M. Flow cytometry as a novel tool for structural and functional characterization of isolated yeast vacuoles. Microbiology (Reading) 2013; 159:848-856. [DOI: 10.1099/mic.0.062570-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- Jorge Rodrigues
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
- Centro de Biologia Molecular e Ambiental (CBMA), Departamento de Biologia, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Rui D. Silva
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
- Centro de Biologia Molecular e Ambiental (CBMA), Departamento de Biologia, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Henrique Noronha
- Centro de Investigação e de Tecnologias Agro-Ambientais e Biológicas (CITAB), Quinta de Prados, 5001-801 Vila Real, Portugal
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Andreia Pedras
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
- Centro de Biologia Molecular e Ambiental (CBMA), Departamento de Biologia, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Hernâni Gerós
- Centro de Investigação e de Tecnologias Agro-Ambientais e Biológicas (CITAB), Quinta de Prados, 5001-801 Vila Real, Portugal
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Manuela Côrte-Real
- Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
- Centro de Biologia Molecular e Ambiental (CBMA), Departamento de Biologia, Campus de Gualtar, 4710-057 Braga, Portugal
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18
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Yeast competence for exogenous DNA uptake: towards understanding its genetic component. Antonie van Leeuwenhoek 2013; 103:1181-207. [DOI: 10.1007/s10482-013-9905-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 03/14/2013] [Indexed: 12/20/2022]
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19
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Saccharomyces cerevisiae Env7 is a novel serine/threonine kinase 16-related protein kinase and negatively regulates organelle fusion at the lysosomal vacuole. Mol Cell Biol 2012; 33:526-42. [PMID: 23166297 DOI: 10.1128/mcb.01303-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Membrane fusion depends on conserved components and is responsible for organelle biogenesis and vesicular trafficking. Yeast vacuoles are dynamic structures analogous to mammalian lysosomes. We report here that yeast Env7 is a novel palmitoylated protein kinase ortholog that negatively regulates vacuolar membrane fusion. Microscopic and biochemical studies confirmed the localization of tagged Env7 at the vacuolar membrane and implicated membrane association via the palmitoylation of its N-terminal Cys13 to -15. In vitro kinase assays established Env7 as a protein kinase. Site-directed mutagenesis of the Env7 alanine-proline-glutamic acid (APE) motif Glu269 to alanine results in an unstable kinase-dead allele that is stabilized and redistributed to the detergent-resistant fraction by interruption of the proteasome system in vivo. Palmitoylation-deficient Env7C13-15S is also kinase dead and mislocalizes to the cytoplasm. Microscopy studies established that env7Δ is defective in maintaining fragmented vacuoles during hyperosmotic response and in buds. ENV7 function is not redundant with a similar role of vacuolar membrane kinase Yck3, as the two do not share a substrate, and ENV7 is not a suppressor of yck3Δ. Bayesian phylogenetic analyses strongly support ENV7 as an ortholog of the gene encoding human STK16, a Golgi apparatus protein kinase with undefined function. We propose that Env7 function in fusion/fission dynamics may be conserved within the endomembrane system.
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20
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Rogers DW, McConnell E, Greig D. Molecular quantification of Saccharomyces cerevisiae α-pheromone secretion. FEMS Yeast Res 2012; 12:668-74. [PMID: 22672638 DOI: 10.1111/j.1567-1364.2012.00817.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/29/2012] [Accepted: 05/31/2012] [Indexed: 11/29/2022] Open
Abstract
Saccharomyces cerevisiae yeast cells court each other by producing an attractive sex pheromone specific to their mating type. Cells detect the sex pheromone from potential mates using a well-defined intracellular signalling cascade that has become a model for studying signal transduction. In contrast, the factors contributing to the production of pheromone itself are poorly characterized, despite the widespread use of the S. cerevisiae α-pheromone secretion pathway in industrial fungal protein expression systems. Progress in understanding pheromone secretion has been hindered by a lack of a precise and quantitative pheromone production assay. Here, we present an ELISA-based method for the quantification of α-pheromone secretion. In the absence of pheromone from the opposite mating type, we found that each cell secretes over 550 mature α-pheromone peptides per second; 90% of this total was produced from MF α1. The addition of a-pheromone more than doubled total α-pheromone secretion. This technique offers several improvements on current methods for measuring α-pheromone production and will allow detailed investigation of the factors regulating pheromone production in yeast.
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Affiliation(s)
- David W Rogers
- Max Planck Institute for Evolutionary Biology, Plön, Germany.
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