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Li Y, Xiao C, Pan Y, Qin L, Zheng L, Zhao M, Huang M. Optimization of Protein Folding for Improved Secretion of Human Serum Albumin Fusion Proteins in Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:18414-18423. [PMID: 37966975 DOI: 10.1021/acs.jafc.3c05330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
The successful expression and secretion of recombinant proteins in cell factories significantly depend on the correct folding of nascent peptides, primarily achieved through disulfide bond formation. Thus, optimizing cellular protein folding is crucial, especially for proteins with complex spatial structures. In this study, protein disulfide isomerases (PDIs) from various species were introduced into Saccharomyces cerevisiae to facilitate proper disulfide bond formation and enhance recombinant protein secretion. The impacts of these PDIs on recombinant protein production and yeast growth metabolism were evaluated by substituting the endogenous PDI1. Heterologous PDIs cannot fully compensate the endogenous PDI. Furthermore, protein folding mediators, PDI and ER oxidoreductase 1 (Ero1), from different species were used to increase the production of complex human serum albumin (HSA) fusion proteins. The validated folding mediators were then introduced into unfolded protein response (UPR)-optimized strains, resulting in a 7.8-fold increase in amylase-HSA and an 18.2-fold increase in albiglutide compared with the control strain. These findings provide valuable insights for optimizing protein folding and expressing HSA-based drugs.
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Affiliation(s)
- Yanling Li
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Chufan Xiao
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Yuyang Pan
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Ling Qin
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Lin Zheng
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Mouming Zhao
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
| | - Mingtao Huang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510650, China
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Liu K, Wang X, Li Y, Shi Y, Ren Y, Wang A, Zhao B, Cheng P, Wang B. Protein Disulfide Isomerase FgEps1 Is a Secreted Virulence Factor in Fusarium graminearum. J Fungi (Basel) 2023; 9:1009. [PMID: 37888265 PMCID: PMC10607971 DOI: 10.3390/jof9101009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/07/2023] [Accepted: 10/10/2023] [Indexed: 10/28/2023] Open
Abstract
Protein disulfide isomerase (PDI) is a member of the thioredoxin (Trx) superfamily with important functions in cellular stability, ion uptake, and cellular differentiation. While PDI has been extensively studied in humans and animals, its role in fungi remains relatively unknown. In this study, the biological functions of FgEps1, a disulfide bond isomerase in the fungal pathogen Fusarium graminearum, were investigated. It was found that FgEps1 mutation affected nutritional growth, asexual and sexual reproduction, and stress tolerance. Additionally, its deletion resulted in reduced pathogenicity and impaired DON toxin biosynthesis. The involvement of FgEps1 in host infection was also confirmed, as its expression was detected during the infection period. Further investigation using a yeast signal peptide secretion system and transient expression in Nicotiana benthamiana showed that FgEps1 suppressed the immune response of plants and promoted infection. These findings suggest that virulence factor FgEps1 plays a crucial role in growth, development, virulence, secondary metabolism, and host infection in F. graminearum.
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Affiliation(s)
| | | | | | | | | | | | | | - Peng Cheng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (K.L.); (X.W.); (Y.L.); (Y.S.); (Y.R.); (A.W.); (B.Z.)
| | - Baotong Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (K.L.); (X.W.); (Y.L.); (Y.S.); (Y.R.); (A.W.); (B.Z.)
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Xia F, Du J, Wang K, Liu L, Ba L, Liu H, Liu Y. Application of Multiple Strategies To Debottleneck the Biosynthesis of Longifolene by Engineered Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:11336-11343. [PMID: 36047715 DOI: 10.1021/acs.jafc.2c04405] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Longifolene as an important sesquiterpene had enormous biological benefits. However, the low productivity of longifolene relying on chemical catalysis and plant extraction limited its wide application. Herein, the longifolene biosynthetic pathway was introduced into Saccharomyces cerevisiae, and multiple genetic strategies were applied to debottleneck the synthesis of longifolene, including the regulation of the rate-limiting enzymes, the elimination of the competitive pathways, the screening of the molecular chaperone to improve synthase activity, and the enhancement of the precursor supply. After combinationally applying these optimum strategies, the production of longifolene reached 27.30 mg/L in shake flasks and 1249 mg/L in fed-batch fermentation, respectively, which was the highest yield of longifolene reported thus far. It was demonstrated that the strategies applied in our work were effective in promoting the biosynthesis of longifolene, which not only laid a significant foundation for its industrial production but also provided a platform for the synthesis of other terpenoids.
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Affiliation(s)
- Furong Xia
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Jingping Du
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Kai Wang
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Lu Liu
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Limin Ba
- Zhongmu Research Institute, China Animal Husbandry Industry Company, Limited, Beijing 100095, People's Republic of China
| | - Huan Liu
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Yanhui Liu
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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Weiß RG, Losfeld ME, Aebi M, Riniker S. N-Glycosylation Enhances Conformational Flexibility of Protein Disulfide Isomerase Revealed by Microsecond Molecular Dynamics and Markov State Modeling. J Phys Chem B 2021; 125:9467-9479. [PMID: 34379416 DOI: 10.1021/acs.jpcb.1c04279] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Secreted proteins of eukaryotes are decorated with branched carbohydrate oligomers called glycans. This fact is only starting to be considered for in silico investigations of protein dynamics. Using all-atom molecular dynamics (MD) simulations and Markov state modeling (MSM), we unveil the influence of glycans on the conformational flexibility of the multidomain protein disulfide isomerase (PDI), which is a ubiquitous chaperone in the endoplasmic reticulum (ER). Yeast PDI (yPDI) from Saccharomyces cerevisiae is glycosylated at asparagine side chains and the knowledge of its five modified sites enables a realistic computational modeling. We compare simulations of glycosylated and unglycosylated yPDI and find that the presence of glycan-glycan and glycan-protein interactions influences the flexibility of PDI in different ways. For example, glycosylation reduces interdomain interactions, shifting the conformational ensemble toward more open, extended structures. In addition, we compare our results on yPDI with structural information of homologous proteins such as human PDI (hPDI), which is natively unglycosylated. Interestingly, hPDI lacks a surface recess that is present in yPDI. We find that glycosylation of yPDI facilitates its catalytic site to reach close to this surface recess. Hence, this might point to a possible functional relevance of glycosylation in yeast to act on substrates, while glycosylation seems redundant for the human homologous protein. We conclude that glycosylation is fundamental for protein dynamics, making it a necessity for a truthful representation of the flexibility and function in in silico studies of glycoproteins.
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Affiliation(s)
- R Gregor Weiß
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich, 8093 Zürich, Switzerland
| | - Marie-Estelle Losfeld
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich, 8093 Zürich, Switzerland
| | - Markus Aebi
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich, 8093 Zürich, Switzerland
| | - Sereina Riniker
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich, 8093 Zürich, Switzerland
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Li H, Liu Q, Xiao K, He Z, Wu C, Sun J, Chen X, Chen S, Yang J, Ma Q, Su J. PDIA4 Correlates with Poor Prognosis and is a Potential Biomarker in Glioma. Onco Targets Ther 2021; 14:125-138. [PMID: 33447054 PMCID: PMC7802790 DOI: 10.2147/ott.s287931] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/21/2020] [Indexed: 01/11/2023] Open
Abstract
Purpose Gliomas, characterized by aggressiveness and invasiveness, remain incurable after conventional therapies. The molecular mechanisms driving the progression and maintenance of glioma are still poorly understood. Methods The TCGA and CGGA databases were chosen for bioinformatics analysis. Gene expression profiling interactive analysis (GEPIA) was performed for differential analysis. The Kaplan–Meier method was chosen for survival analysis. Analysis of stromal and immune infiltration was performed using the ESTIMATE algorithm and xCell package. qPCR and Western blotting were performed to measure the expression of PDIA4 at the mRNA and protein levels. IHC was performed to detect the expression of PDIA4 in glioma tissues. The viability of glioma cells was evaluated by the CCK8 assay. Results In this study, we identified high PDIA4 expression in gliomas that correlated with poor prognosis. The association between IDH1 and different glioma patterns also indicated the potential biological role of PDIA4 in tumor development. Mechanistically, PDIA4 interacted with multiple immunological components to promote an immunosuppressive tumor microenvironment (TME). Knockdown of PDIA4 significantly impaired the proliferation of GBM cells. Conclusion Our results confirm that PDIA4 is an efficient biomarker of gliomas, with clinical implications for prognosis and therapeutic strategies.
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Affiliation(s)
- Haoyu Li
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Qing Liu
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Kai Xiao
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Zhengxi He
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Chao Wu
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Jianjun Sun
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Xin Chen
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Suhua Chen
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Jun Yang
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Qianquan Ma
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing 100191, People's Republic of China
| | - Jun Su
- Department of Neurosurgery, Hunan Children's Hospital, Changsha 410007, Hunan, People's Republic of China
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Murakami Y, Futamata R, Horibe T, Ueda K, Kinoshita M. CRISPR/Cas9 nickase‐mediated efficient and seamless knock‐in of lethal genes in the medaka fish
Oryzias latipes. Dev Growth Differ 2020; 62:554-567. [DOI: 10.1111/dgd.12700] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/01/2020] [Accepted: 11/01/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Yu Murakami
- Division of Applied Biosciences Graduate School of Agriculture Kyoto University Kyoto Japan
| | - Ryota Futamata
- Division of Applied Life Sciences Graduate School of Agriculture Kyoto University Kyoto Japan
| | - Tomohisa Horibe
- Department of Medical‐Bioscience Faculty of Bio‐Science Nagahama Institute of Bio‐Science and Technology Shiga Japan
| | - Kazumitsu Ueda
- Institute for integrated Cell‐Material Sciences (WPI‐iCeMS)KUIASKyoto University Kyoto Japan
| | - Masato Kinoshita
- Division of Applied Biosciences Graduate School of Agriculture Kyoto University Kyoto Japan
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He H, Wu S, Mei M, Ning J, Li C, Ma L, Zhang G, Yi L. A Combinational Strategy for Effective Heterologous Production of Functional Human Lysozyme in Pichia pastoris. Front Bioeng Biotechnol 2020; 8:118. [PMID: 32211388 PMCID: PMC7075855 DOI: 10.3389/fbioe.2020.00118] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 02/06/2020] [Indexed: 11/13/2022] Open
Abstract
Human lysozyme (hLYZ), known for its bacteriolytic activity, is widely applied in the food and pharmaceutical industries as an antimicrobial agent. However, its extensive application was limited by its low large-scale production efficiency. In this study, a combinational method of integrating codon optimization, multiple gene copies, and ER molecular chaperone co-expression was developed to improve the heterologous production of hLYZ in Pichia pastoris GS115. Our results showed that increasing the copy number of the optimized hLYZ gene in P. pastoris could enhance its secretory production level up to 1.57-fold. The recombinant opt-hLYZ-6C strain that contains six copies of opt-hLYZ gene exhibited the highest mRNA transcription levels, giving the highest production of 0.22 ± 0.02 mg/mL of hLYZ in the medium supernatant with a bacteriolytic activity of 14,680 ± 300 U/mL against Micrococcus lysodeikticus in the shaking flask experiment. Moreover, co-overexpression of ER retention molecular chaperones, such as Pdi1 or Ero1, in the recombinant opt-hLYZ-6C strain both presented positive effects on the secretory production of hLYZ. Our further characterization indicated that tandem co-expression of Ero1 and Pdi1 together presented an added-up effect. The secretory production of hLYZ in the medium supernatant reached 0.34 ± 0.02 mg/mL of the recombinant opt-hLYZ-6C-EP strain in the shaking flask experiment, with a bacteriolytic activity of 21,200 ± 400 U/mL. Compared to the recombinant opt-hLYZ-1C strain, these final improvements were calculated as 2.43-fold and 2.30-fold on secretory protein levels and antibacterial activity, respectively. Finally, the recombinant opt-hLYZ-6C-EP strain was applied for high-density cultivation in 5 L of fermenter, in which the secretory yield of hLYZ reached 2.34 ± 0.02 mg/mL in the medium supernatant, with a bacteriolytic activity of 1.76 ± 0.02 × 105 U/mL against M. lysodeikticus. All these numbers presented the highest heterologous production levels of hLYZ in microbial systems.
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Affiliation(s)
- Huahua He
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Shijie Wu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Meng Mei
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Jiali Ning
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Chaoyin Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Lixin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Guimin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
| | - Li Yi
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, China
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Zhang J, Wu J, Liu L, Li J. The Crucial Role of Demannosylating Asparagine-Linked Glycans in ERADicating Misfolded Glycoproteins in the Endoplasmic Reticulum. FRONTIERS IN PLANT SCIENCE 2020; 11:625033. [PMID: 33510762 PMCID: PMC7835635 DOI: 10.3389/fpls.2020.625033] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/08/2020] [Indexed: 05/04/2023]
Abstract
Most membrane and secreted proteins are glycosylated on certain asparagine (N) residues in the endoplasmic reticulum (ER), which is crucial for their correct folding and function. Protein folding is a fundamentally inefficient and error-prone process that can be easily interfered by genetic mutations, stochastic cellular events, and environmental stresses. Because misfolded proteins not only lead to functional deficiency but also produce gain-of-function cellular toxicity, eukaryotic organisms have evolved highly conserved ER-mediated protein quality control (ERQC) mechanisms to monitor protein folding, retain and repair incompletely folded or misfolded proteins, or remove terminally misfolded proteins via a unique ER-associated degradation (ERAD) mechanism. A crucial event that terminates futile refolding attempts of a misfolded glycoprotein and diverts it into the ERAD pathway is executed by removal of certain terminal α1,2-mannose (Man) residues of their N-glycans. Earlier studies were centered around an ER-type α1,2-mannosidase that specifically cleaves the terminal α1,2Man residue from the B-branch of the three-branched N-linked Man9GlcNAc2 (GlcNAc for N-acetylglucosamine) glycan, but recent investigations revealed that the signal that marks a terminally misfolded glycoprotein for ERAD is an N-glycan with an exposed α1,6Man residue generated by members of a unique folding-sensitive α1,2-mannosidase family known as ER-degradation enhancing α-mannosidase-like proteins (EDEMs). This review provides a historical recount of major discoveries that led to our current understanding on the role of demannosylating N-glycans in sentencing irreparable misfolded glycoproteins into ERAD. It also discusses conserved and distinct features of the demannosylation processes of the ERAD systems of yeast, mammals, and plants.
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Affiliation(s)
- Jianjun Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Jiarui Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Linchuan Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Jianming Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- *Correspondence: Jianming Li, ;
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Mei M, Li J, Wang S, Lee KB, Iverson BL, Zhang G, Ge X, Yi L. Prompting Fab Yeast Surface Display Efficiency by ER Retention and Molecular Chaperon Co-expression. Front Bioeng Biotechnol 2019; 7:362. [PMID: 32039168 PMCID: PMC6988814 DOI: 10.3389/fbioe.2019.00362] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/12/2019] [Indexed: 12/15/2022] Open
Abstract
For antibody discovery and engineering, yeast surface display (YSD) of antigen-binding fragments (Fabs) and coupled fluorescence activated cell sorting (FACS) provide intact paratopic conformations and quantitative analysis at the monoclonal level, and thus holding great promises for numerous applications. Using anti-TNFα mAbs Infliximab, Adalimumab, and its variants as model Fabs, this study systematically characterized complementary approaches for the optimization of Fab YSD. Results suggested that by using divergent promoter GAL1-GAL10 and endoplasmic reticulum (ER) signal peptides for co-expression of light chain and heavy chain-Aga2 fusion, assembled Fabs were functionally displayed on yeast cell surface with sigmoidal binding responses toward TNFα. Co-expression of a Hsp70 family molecular chaperone Kar2p and/or protein-disulfide isomerase (Pdi1p) significantly improved efficiency of functional display (defined as the ratio of cells displaying functional Fab over cells displaying assembled Fab). Moreover, fusing ER retention sequences (ERSs) with light chain also enhanced Fab display quality at the expense of display quantity, and the degree of improvements was correlated with the strength of ERSs and was more significant for Infliximab than Adalimumab. The feasibility of affinity maturation was further demonstrated by isolating a high affinity Fab clone from 1:103 or 1:105 spiked libraries.
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Affiliation(s)
- Meng Mei
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Junhong Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Shengchen Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Ki Baek Lee
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, CA, United States
| | - Brent L Iverson
- Department of Chemistry, University of Texas, Austin, TX, United States
| | - Guimin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Xin Ge
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, CA, United States
| | - Li Yi
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
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10
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Beal DM, Bastow EL, Staniforth GL, von der Haar T, Freedman RB, Tuite MF. Quantitative Analyses of the Yeast Oxidative Protein Folding Pathway In Vitro and In Vivo. Antioxid Redox Signal 2019; 31:261-274. [PMID: 30880408 PMCID: PMC6602113 DOI: 10.1089/ars.2018.7615] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 03/14/2019] [Accepted: 03/14/2019] [Indexed: 12/11/2022]
Abstract
Aims: Efficient oxidative protein folding (OPF) in the endoplasmic reticulum (ER) is a key requirement of the eukaryotic secretory pathway. In particular, protein folding linked to the formation of disulfide bonds, an activity dependent on the enzyme protein disulfide isomerase (PDI), is crucial. For the de novo formation of disulfide bonds, reduced PDI must be reoxidized by an ER-located oxidase (ERO1). Despite some knowledge of this pathway, the kinetic parameters with which these components act and the importance of specific parameters, such as PDI reoxidation by Ero1, for the overall performance of OPF in vivo remain poorly understood. Results: We established an in vitro system using purified yeast (Saccharomyces cerevisiae) PDI (Pdi1p) and ERO1 (Ero1p) to investigate OPF. This necessitated the development of a novel reduction/oxidation processing strategy to generate homogenously oxidized recombinant yeast Ero1p. This new methodology enabled the quantitative assessment of the interaction of Pdi1p and Ero1p in vitro by measuring oxygen consumption and reoxidation of reduced RNase A. The resulting quantitative data were then used to generate a simple model that can describe the oxidizing capacity of Pdi1p and Ero1p in vitro and predict the in vivo effect of modulation of the levels of these proteins. Innovation: We describe a model that can be used to explore the OPF pathway and its control in a quantitative way. Conclusion: Our study informs and provides new insights into how OPF works at a molecular level and provides a platform for the design of more efficient heterologous protein expression systems in yeast.
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Affiliation(s)
- Dave M. Beal
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Emma L. Bastow
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Gemma L. Staniforth
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Tobias von der Haar
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Robert B. Freedman
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
- School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry, United Kingdom
| | - Mick F. Tuite
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, United Kingdom
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11
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Mares RE, Ramos MA. An amebic protein disulfide isomerase (PDI) complements the yeast PDI1 mutation but is unable to support cell viability under ER or thermal stress. FEBS Open Bio 2017; 8:49-55. [PMID: 29321956 PMCID: PMC5757170 DOI: 10.1002/2211-5463.12350] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 10/18/2017] [Accepted: 11/07/2017] [Indexed: 01/04/2023] Open
Abstract
In eukaryotic cells, protein disulfide isomerases (PDI) are oxidoreductases that catalyze the proper disulfide bond formation during protein folding. The pathobiology of the protozoan parasite Entamoeba histolytica, the causative agent of human amebiasis, depends on secretion of several virulence factors, such as pore‐forming peptides and cysteine proteinases. Although the native conformation of these factors is stabilized by disulfide bonds, there is little information regarding the molecular machinery involved in the oxidative folding of amebic proteins. Whereas testing gene function in their physiological background would be the most suitable approach, we have taken advantage of the cellular benefits offered by the yeast Saccharomyces cerevisiae (as a model of eukaryotic cell) to examine the functional role of an amebic PDI (EhPDI). As the yeast PDI homolog is essential for cell viability, a functional complementation assay was carried out to test the ability of EhPDI to circumvent the lethal phenotype of a yeast PDI1 mutant. Also, its proficiency under stressful conditions was explored by examining the survival outcome following endoplasmic reticulum (ER) stress induced by a reductant agent (DTT) or thermal stress promoted by a nonpermissive temperature (37 °C). Our results indicate that EhPDI is functionally active when physiological conditions are stable. Nonetheless, when conditions are stressful (e.g., by the accumulation of misfolded proteins in the ER compartment), its functionality is exceeded, suggesting an inability to prevent unfolding, suppress aggregation, or assist refolding of proteins. Despite the latter, our findings constitute the initial step toward determining the participation of EhPDI in cellular mechanisms related to protein homeostasis.
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Affiliation(s)
- Rosa E Mares
- Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma de Baja California Tijuana Baja California México
| | - Marco A Ramos
- Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma de Baja California Tijuana Baja California México
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Mei M, Zhai C, Li X, Zhou Y, Peng W, Ma L, Wang Q, Iverson BL, Zhang G, Yi L. Characterization of aromatic residue-controlled protein retention in the endoplasmic reticulum of Saccharomyces cerevisiae. J Biol Chem 2017; 292:20707-20719. [PMID: 29038295 DOI: 10.1074/jbc.m117.812107] [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: 08/15/2017] [Revised: 10/11/2017] [Indexed: 01/05/2023] Open
Abstract
An endoplasmic reticulum (ER) retention sequence (ERS) is a characteristic short sequence that mediates protein retention in the ER of eukaryotic cells. However, little is known about the detailed molecular mechanism involved in ERS-mediated protein ER retention. Using a new surface display-based fluorescence technique that effectively quantifies ERS-promoted protein ER retention within Saccharomyces cerevisiae cells, we performed comprehensive ERS analyses. We found that the length, type of amino acid residue, and additional residues at positions -5 and -6 of the C-terminal HDEL motif all determined the retention of ERS in the yeast ER. Moreover, the biochemical results guided by structure simulation revealed that aromatic residues (Phe-54, Trp-56, and other aromatic residues facing the ER lumen) in both the ERS (at positions -6 and -4) and its receptor, Erd2, jointly determined their interaction with each other. Our studies also revealed that this aromatic residue interaction might lead to the discriminative recognition of HDEL or KDEL as ERS in yeast or human cells, respectively. Our findings expand the understanding of ERS-mediated residence of proteins in the ER and may guide future research into protein folding, modification, and translocation affected by ER retention.
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Affiliation(s)
- Meng Mei
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Chao Zhai
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Xinzhi Li
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Yu Zhou
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Wenfang Peng
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Lixin Ma
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China
| | - Qinhong Wang
- the Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China, and
| | - Brent L Iverson
- the Department of Chemistry, University of Texas, Austin, Texas 78712
| | - Guimin Zhang
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China,
| | - Li Yi
- From the Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei Key Laboratory of Industrial Biotechnology, Hubei University, Wuhan 430062, China,
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'Something in the way she moves': The functional significance of flexibility in the multiple roles of protein disulfide isomerase (PDI). BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1383-1394. [PMID: 28844745 PMCID: PMC5654723 DOI: 10.1016/j.bbapap.2017.08.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/30/2017] [Accepted: 08/10/2017] [Indexed: 01/15/2023]
Abstract
Protein disulfide isomerase (PDI) has diverse functions in the endoplasmic reticulum as catalyst of redox transfer, disulfide isomerization and oxidative protein folding, as molecular chaperone and in multi-subunit complexes. It interacts with an extraordinarily wide range of substrate and partner proteins, but there is only limited structural information on these interactions. Extensive evidence on the flexibility of PDI in solution is not matched by any detailed picture of the scope of its motion. A new rapid method for simulating the motion of large proteins provides detailed molecular trajectories for PDI demonstrating extensive changes in the relative orientation of its four domains, great variation in the distances between key sites and internal motion within the core ligand-binding domain. The review shows that these simulations are consistent with experimental evidence and provide insight into the functional capabilities conferred by the extensive flexible motion of PDI.
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Marschall R, Tudzynski P. The Protein Disulfide Isomerase of Botrytis cinerea: An ER Protein Involved in Protein Folding and Redox Homeostasis Influences NADPH Oxidase Signaling Processes. Front Microbiol 2017; 8:960. [PMID: 28611757 PMCID: PMC5447010 DOI: 10.3389/fmicb.2017.00960] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/15/2017] [Indexed: 11/13/2022] Open
Abstract
Botrytis cinerea is a filamentous plant pathogen, which infects hundreds of plant species; within its lifestyle, the production of reactive oxygen species (ROS) and a balanced redox homeostasis are essential parameters. The pathogen is capable of coping with the plant’s oxidative burst and even produces its own ROS to enhance the plant’s oxidative burst. Highly conserved NADPH oxidase (Nox) complexes produce the reactive molecules. The membrane-associated complexes regulate a large variety of vegetative and pathogenic processes. Besides their commonly accepted function at the plasma membrane, recent studies reveal that Nox complexes are also active at the membrane of the endoplasmic reticulum. In this study, we identified the essential ER protein BcPdi1 as new interaction partner of the NoxA complex in B. cinerea. Mutants that lack this ER chaperone display overlapping phenotypes to mutants of the NoxA signaling pathway. The protein appears to be involved in all major developmental processes, such as the formation of sclerotia, conidial anastomosis tubes and infection cushions (IC’s) and is needed for full virulence. Moreover, expression analyses and reporter gene studies indicate that BcPdi1 affects the redox homeostasis and unfolded protein response (UPR)-related genes. Besides the close association between BcPdi1 and BcNoxA, interaction studies provide evidence that the ER protein might likewise be involved in Ca2+ regulated processes. Finally, we were able to show that the potential key functions of the protein BcPdi1 might be affected by its phosphorylation state.
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Affiliation(s)
- Robert Marschall
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität MünsterMünster, Germany
| | - Paul Tudzynski
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität MünsterMünster, Germany
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15
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Protein disulfide isomerase a4 acts as a novel regulator of cancer growth through the procaspase pathway. Oncogene 2017; 36:5484-5496. [PMID: 28534513 DOI: 10.1038/onc.2017.156] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 04/18/2017] [Accepted: 04/19/2017] [Indexed: 12/21/2022]
Abstract
Protein disulfide isomerase a4 (PDIA4) is implicated in the growth and death of tumor cells; however, its molecular mechanism and therapeutic potential in cancer are unclear. Here, we found that PDIA4 expression was upregulated in a variety of tumor cell lines and human lung adenocarcinoma tissues. Knockdown and overexpression of PDIA4 in tumor cells showed that PDIA4 facilitated cell growth via the reduction of caspases 3 and 7 activity. Consistently, Lewis lung carcinoma cells overexpressing PDIA4 grew faster than did parental cells in tumor-bearing mice, as shown by a reduced survival rate, increased tumor size and metastasis, and decreased cell death and caspases 3 and 7 activity. PDIA4 knockdown resulted in opposite outcomes. Moreover, results obtained in mice with spontaneous hepatoma indicated that PDIA4 deficiency significantly reduced hepatic tumorigenesis and cyst formation and increased mouse survival, tumor death, and caspases 3 and 7 activity. Mechanistic studies illustrated that PDIA4 negatively regulated tumor cell death by inhibiting degradation and activation of procaspases 3 and 7 via their mutual interaction in a CGHC-dependent manner. Finally, we found that 1,2-dihydroxytrideca-5,7,9,11-tetrayne, a PDIA4 inhibitor, reduced tumor development via enhancement of caspase-mediated cell death in TSA tumor-bearing mice. These findings characterize PDIA4 as a negative regulator of cancer cell apoptosis and suggest that PDIA4 is a potential therapeutic target for cancer.
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16
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Pfeiffer A, Stephanowitz H, Krause E, Volkwein C, Hirsch C, Jarosch E, Sommer T. A Complex of Htm1 and the Oxidoreductase Pdi1 Accelerates Degradation of Misfolded Glycoproteins. J Biol Chem 2016; 291:12195-207. [PMID: 27053108 DOI: 10.1074/jbc.m115.703256] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 11/06/2022] Open
Abstract
A quality control system in the endoplasmic reticulum (ER) efficiently discriminates polypeptides that are in the process of productive folding from conformers that are trapped in an aberrant state. Only the latter are transported into the cytoplasm and degraded in a process termed ER-associated protein degradation (ERAD). In the ER, an enzymatic cascade generates a specific N-glycan structure of seven mannosyl and two N-acetylglucosamine residues (Man7GlcNAc2) on misfolded glycoproteins to facilitate their disposal. We show that a complex encompassing the yeast lectin-like protein Htm1 and the oxidoreductase Pdi1 converts Man8GlcNAc2 on glycoproteins into the Man7GlcNAc2 signal. In vitro the Htm1-Pdi1 complex processes both unfolded and native proteins albeit with a preference for the former. In vivo, elevated expression of HTM1 causes glycan trimming on misfolded and folded proteins, but only degradation of the non-native species is accelerated. Thus, modification with a Man7GlcNAc2 structure does not inevitably commit a protein for ER-associated protein degradation. The function of Htm1 in ERAD relies on its association with Pdi1, which appears to regulate the access to substrates. Our data support a model in which the balanced activities of Pdi1 and Htm1 are crucial determinants for the efficient removal of misfolded secretory glycoproteins.
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Affiliation(s)
| | - Heike Stephanowitz
- the Leibniz Institute for Molecular Pharmacology, 13125 Berlin, Germany and
| | - Eberhard Krause
- the Leibniz Institute for Molecular Pharmacology, 13125 Berlin, Germany and
| | | | | | - Ernst Jarosch
- From the Max-Delbrück-Center for Molecular Medicine and
| | - Thomas Sommer
- From the Max-Delbrück-Center for Molecular Medicine and Humboldt University, Faculty of Life Science, Institute of Biology, 10099 Berlin, Germany
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Stothert AR, Fontaine SN, Sabbagh JJ, Dickey CA. Targeting the ER-autophagy system in the trabecular meshwork to treat glaucoma. Exp Eye Res 2015; 144:38-45. [PMID: 26302411 DOI: 10.1016/j.exer.2015.08.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/23/2015] [Accepted: 08/18/2015] [Indexed: 12/19/2022]
Abstract
A major drainage network involved in aqueous humor dynamics is the conventional outflow pathway, which is gated by the trabecular meshwork (TM). The TM acts as a molecular sieve, providing resistance to aqueous outflow, which is responsible for regulating intraocular pressure (IOP). If the TM is damaged, aqueous outflow is impaired, IOP increases and glaucoma can manifest. Mutations in the MYOC gene cause hereditary primary open-angle glaucoma (POAG) by promoting the abnormal amyloidosis of the myocilin protein in the endoplasmic reticulum (ER), leading to ER stress-induced TM cell death. Myocilin accumulation is observed in approximately 70-80% of all glaucoma cases suggesting that environmental or other genetic factors may also promote myocilin toxicity. For example, simply preventing myocilin glycosylation is sufficient to promote its abnormal accretion. These myocilin amyloids are unique as there are no other known pathogenic proteins that accumulate within the ER of TM cells and cause toxicity. Moreover, this pathogenic accumulation only kills TM cells, despite expression of this protein in other cell types, suggesting that another modifier exclusive to the TM participates in the proteotoxicity of myocilin. ER autophagy (reticulophagy) is one of the pathways essential for myocilin clearance that can be impacted dramatically by aging and other environmental factors such as nutrition. This review will discuss the link between myocilin and autophagy, evaluating the role of this degradation pathway in glaucoma as well as its potential as a therapeutic target.
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Affiliation(s)
- Andrew R Stothert
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, University of South Florida, Tampa, FL 33613, USA
| | - Sarah N Fontaine
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, University of South Florida, Tampa, FL 33613, USA
| | - Jonathan J Sabbagh
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, University of South Florida, Tampa, FL 33613, USA
| | - Chad A Dickey
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, University of South Florida, Tampa, FL 33613, USA.
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18
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Biran S, Gat Y, Fass D. The Eps1p protein disulfide isomerase conserves classic thioredoxin superfamily amino acid motifs but not their functional geometries. PLoS One 2014; 9:e113431. [PMID: 25437863 PMCID: PMC4249923 DOI: 10.1371/journal.pone.0113431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 10/24/2014] [Indexed: 02/04/2023] Open
Abstract
The widespread thioredoxin superfamily enzymes typically share the following features: a characteristic α-β fold, the presence of a Cys-X-X-Cys (or Cys-X-X-Ser) redox-active motif, and a proline in the cis configuration abutting the redox-active site in the tertiary structure. The Cys-X-X-Cys motif is at the solvent-exposed amino terminus of an α-helix, allowing the first cysteine to engage in nucleophilic attack on substrates, or substrates to attack the Cys-X-X-Cys disulfide, depending on whether the enzyme functions to reduce, isomerize, or oxidize its targets. We report here the X-ray crystal structure of an enzyme that breaks many of our assumptions regarding the sequence-structure relationship of thioredoxin superfamily proteins. The yeast Protein Disulfide Isomerase family member Eps1p has Cys-X-X-Cys motifs and proline residues at the appropriate primary structural positions in its first two predicted thioredoxin-fold domains. However, crystal structures show that the Cys-X-X-Cys of the second domain is buried and that the adjacent proline is in the trans, rather than the cis isomer. In these configurations, neither the “active-site” disulfide nor the backbone carbonyl preceding the proline is available to interact with substrate. The Eps1p structures thus expand the documented diversity of the PDI oxidoreductase family and demonstrate that conserved sequence motifs in common folds do not guarantee structural or functional conservation.
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Affiliation(s)
- Shai Biran
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Yair Gat
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Deborah Fass
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
- * E-mail:
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Byun H, Gou Y, Zook A, Lozano MM, Dudley JP. ERAD and how viruses exploit it. Front Microbiol 2014; 5:330. [PMID: 25071743 PMCID: PMC4080680 DOI: 10.3389/fmicb.2014.00330] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 06/16/2014] [Indexed: 01/09/2023] Open
Abstract
Endoplasmic reticulum (ER)-associated degradation (ERAD) is a universally important process among eukaryotic cells. ERAD is necessary to preserve cell integrity since the accumulation of defective proteins results in diseases associated with neurological dysfunction, cancer, and infections. This process involves recognition of misfolded or misassembled proteins that have been translated in association with ER membranes. Recognition of ERAD substrates leads to their extraction through the ER membrane (retrotranslocation or dislocation), ubiquitination, and destruction by cytosolic proteasomes. This review focuses on ERAD and its components as well as how viruses use this process to promote their replication and to avoid the immune response.
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Affiliation(s)
- Hyewon Byun
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Yongqiang Gou
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Adam Zook
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Mary M Lozano
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Jaquelin P Dudley
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
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Bergdahl B, Gorwa-Grauslund MF, van Niel EWJ. Physiological effects of over-expressing compartment-specific components of the protein folding machinery in xylose-fermenting Saccharomyces cerevisiae. BMC Biotechnol 2014; 14:28. [PMID: 24758421 PMCID: PMC4021093 DOI: 10.1186/1472-6750-14-28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 04/11/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Efficient utilization of both glucose and xylose is necessary for a competitive ethanol production from lignocellulosic materials. Although many advances have been made in the development of xylose-fermenting strains of Saccharomyces cerevisiae, the productivity remains much lower compared to glucose. Previous transcriptional analyses of recombinant xylose-fermenting strains have mainly focused on central carbon metabolism. Very little attention has been given to other fundamental cellular processes such as the folding of proteins. Analysis of previously measured transcript levels in a recombinant XR/XDH-strain showed a wide down-regulation of genes targeted by the unfolded protein response during xylose fermentation. Under anaerobic conditions the folding of proteins is directly connected with fumarate metabolism and requires two essential enzymes: FADH2-dependent fumarate reductase (FR) and Ero1p. In this study we tested whether these enzymes impair the protein folding process causing the very slow growth of recombinant yeast strains on xylose under anaerobic conditions. RESULTS Four strains over-expressing the cytosolic (FRD1) or mitochondrial (OSM1) FR genes and ERO1 in different combinations were constructed. The growth and fermentation performance was evaluated in defined medium as well as in a complex medium containing glucose and xylose. Over-expression of FRD1, alone or in combination with ERO1, did not have any significant effect on xylose fermentation in any medium used. Over-expression of OSM1, on the other hand, led to a diversion of carbon from glycerol to acetate and a decrease in growth rate by 39% in defined medium and by 25% in complex medium. Combined over-expression of OSM1 and ERO1 led to the same diversion of carbon from glycerol to acetate and had a stronger detrimental effect on the growth in complex medium. CONCLUSIONS Increasing the activities of the FR enzymes and Ero1p is not sufficient to increase the anaerobic growth on xylose. So additional components of the protein folding mechanism that were identified in transcription analysis of UPR related genes may also be limiting. This includes i) the transcription factor encoded by HAC1 ii) the activity of Pdi1p and iii) the requirement of free FAD during anaerobic growth.
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Affiliation(s)
- Basti Bergdahl
- Division of Applied Microbiology, Department of Chemistry, Lund University, P,O, Box 124, Lund SE-22100, Sweden.
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Oxidative protein-folding systems in plant cells. Int J Cell Biol 2013; 2013:585431. [PMID: 24187554 PMCID: PMC3800646 DOI: 10.1155/2013/585431] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 08/01/2013] [Indexed: 12/13/2022] Open
Abstract
Plants are unique among eukaryotes in having evolved organelles: the protein storage vacuole, protein body, and chloroplast. Disulfide transfer pathways that function in the endoplasmic reticulum (ER) and chloroplasts of plants play critical roles in the development of protein storage organelles and the biogenesis of chloroplasts, respectively. Disulfide bond formation requires the cooperative function of disulfide-generating enzymes (e.g., ER oxidoreductase 1), which generate disulfide bonds de novo, and disulfide carrier proteins (e.g., protein disulfide isomerase), which transfer disulfides to substrates by means of thiol-disulfide exchange reactions. Selective molecular communication between disulfide-generating enzymes and disulfide carrier proteins, which reflects the molecular and structural diversity of disulfide carrier proteins, is key to the efficient transfer of disulfides to specific sets of substrates. This review focuses on recent advances in our understanding of the mechanisms and functions of the various disulfide transfer pathways involved in oxidative protein folding in the ER, chloroplasts, and mitochondria of plants.
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Abstract
The secretory pathway is responsible for the synthesis, folding, and delivery of a diverse array of cellular proteins. Secretory protein synthesis begins in the endoplasmic reticulum (ER), which is charged with the tasks of correctly integrating nascent proteins and ensuring correct post-translational modification and folding. Once ready for forward traffic, proteins are captured into ER-derived transport vesicles that form through the action of the COPII coat. COPII-coated vesicles are delivered to the early Golgi via distinct tethering and fusion machineries. Escaped ER residents and other cycling transport machinery components are returned to the ER via COPI-coated vesicles, which undergo similar tethering and fusion reactions. Ultimately, organelle structure, function, and cell homeostasis are maintained by modulating protein and lipid flux through the early secretory pathway. In the last decade, structural and mechanistic studies have added greatly to the strong foundation of yeast genetics on which this field was built. Here we discuss the key players that mediate secretory protein biogenesis and trafficking, highlighting recent advances that have deepened our understanding of the complexity of this conserved and essential process.
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Young CL, Raden DL, Robinson AS. Analysis of ER resident proteins in Saccharomyces cerevisiae: implementation of H/KDEL retrieval sequences. Traffic 2013; 14:365-81. [PMID: 23324027 DOI: 10.1111/tra.12041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 01/07/2013] [Accepted: 01/16/2013] [Indexed: 01/20/2023]
Abstract
An elaborate quality control system regulates endoplasmic reticulum (ER) homeostasis by ensuring the fidelity of protein synthesis and maturation. In budding yeast, genomic analyses and high-throughput proteomic studies have identified ER resident proteins that restore homeostasis following local perturbations. Yet, how these folding factors modulate stress has been largely unexplored. In this study, we designed a series of polymerase chain reaction (PCR)-based modules including codon-optimized epitopes and fluorescent protein (FP) variants complete with C-terminal H/KDEL retrieval motifs. These conserved sequences are inherent to most soluble ER resident proteins. To monitor multiple proteins simultaneously, H/KDEL cassettes are available with six different selection markers, providing optimal flexibility for live-cell imaging and multicolor labeling in vivo. A single pair of PCR primers can be used for the amplification of these 26 modules, enabling numerous combinations of tags and selection markers. The versatility of pCY H/KDEL cassettes was demonstrated by labeling BiP/Kar2p, Pdi1p and Scj1p with all novel tags, thus providing a direct comparison among FP variants. Furthermore, to advance in vitro studies of yeast ER proteins, Strep-tag II was engineered with a C-terminal retrieval sequence. Here, an efficient purification strategy was established for BiP under physiological conditions.
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Affiliation(s)
- Carissa L Young
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA
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Biology of the heat shock response and protein chaperones: budding yeast (Saccharomyces cerevisiae) as a model system. Microbiol Mol Biol Rev 2012; 76:115-58. [PMID: 22688810 DOI: 10.1128/mmbr.05018-11] [Citation(s) in RCA: 362] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The eukaryotic heat shock response is an ancient and highly conserved transcriptional program that results in the immediate synthesis of a battery of cytoprotective genes in the presence of thermal and other environmental stresses. Many of these genes encode molecular chaperones, powerful protein remodelers with the capacity to shield, fold, or unfold substrates in a context-dependent manner. The budding yeast Saccharomyces cerevisiae continues to be an invaluable model for driving the discovery of regulatory features of this fundamental stress response. In addition, budding yeast has been an outstanding model system to elucidate the cell biology of protein chaperones and their organization into functional networks. In this review, we evaluate our understanding of the multifaceted response to heat shock. In addition, the chaperone complement of the cytosol is compared to those of mitochondria and the endoplasmic reticulum, organelles with their own unique protein homeostasis milieus. Finally, we examine recent advances in the understanding of the roles of protein chaperones and the heat shock response in pathogenic fungi, which is being accelerated by the wealth of information gained for budding yeast.
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Haque SJ, Majumdar T, Barik S. Redox-assisted protein folding systems in eukaryotic parasites. Antioxid Redox Signal 2012; 17:674-83. [PMID: 22122448 PMCID: PMC3373220 DOI: 10.1089/ars.2011.4433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
SIGNIFICANCE The cysteine (Cys) residues of proteins play two fundamentally important roles. They serve as sites of post-translational redox modifications as well as influence the conformation of the protein through the formation of disulfide bonds. RECENT ADVANCES Redox-related and redox-associated protein folding in protozoan parasites has been found to be a major mode of regulation, affecting myriad aspects of the parasitic life cycle, host-parasite interactions, and the disease pathology. Available genome sequences of various parasites have begun to complement the classical biochemical and enzymological studies of these processes. In this article, we summarize the reversible Cys disulfide (S-S) bond formation in various classes of strategically important parasitic proteins, and its structural consequence and functional relevance. CRITICAL ISSUES Molecular mechanisms of folding remain under-studied and often disconnected from functional relevance. FUTURE DIRECTIONS The clinical benefit of redox research will require a comprehensive characterization of the various isoforms and paralogs of the redox enzymes and their concerted effect on the structure and function of the specific parasitic client proteins.
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Affiliation(s)
- Saikh Jaharul Haque
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
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Grubb S, Guo L, Fisher EA, Brodsky JL. Protein disulfide isomerases contribute differentially to the endoplasmic reticulum-associated degradation of apolipoprotein B and other substrates. Mol Biol Cell 2011; 23:520-32. [PMID: 22190736 PMCID: PMC3279382 DOI: 10.1091/mbc.e11-08-0704] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
ER-associated degradation (ERAD) rids the early secretory pathway of misfolded or misprocessed proteins. Some members of the protein disulfide isomerase (PDI) family appear to facilitate ERAD substrate selection and retrotranslocation, but a thorough characterization of PDIs during the degradation of diverse substrates has not been undertaken, in part because there are 20 PDI family members in mammals. PDIs can also exhibit disulfide redox, isomerization, and/or chaperone activity, but which of these activities is required for the ERAD of different substrate classes is unknown. We therefore examined the fates of unique substrates in yeast, which expresses five PDIs. Through the use of a yeast expression system for apolipoprotein B (ApoB), which is disulfide rich, we discovered that Pdi1 interacts with ApoB and facilitates degradation through its chaperone activity. In contrast, Pdi1's redox activity was required for the ERAD of CPY* (a misfolded version of carboxypeptidase Y that has five disulfide bonds). The ERAD of another substrate, the alpha subunit of the epithelial sodium channel, was Pdi1 independent. Distinct effects of mammalian PDI homologues on ApoB degradation were then observed in hepatic cells. These data indicate that PDIs contribute to the ERAD of proteins through different mechanisms and that PDI diversity is critical to recognize the spectrum of potential ERAD substrates.
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Affiliation(s)
- Sarah Grubb
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
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Gauss R, Kanehara K, Carvalho P, Ng DTW, Aebi M. A complex of Pdi1p and the mannosidase Htm1p initiates clearance of unfolded glycoproteins from the endoplasmic reticulum. Mol Cell 2011; 42:782-93. [PMID: 21700223 DOI: 10.1016/j.molcel.2011.04.027] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 03/18/2011] [Accepted: 04/18/2011] [Indexed: 01/13/2023]
Abstract
Endoplasmic reticulum (ER)-resident mannosidases generate asparagine-linked oligosaccharide signals that trigger ER-associated protein degradation (ERAD) of unfolded glycoproteins. In this study, we provide in vitro evidence that a complex of the yeast protein disulfide isomerase Pdi1p and the mannosidase Htm1p processes Man(8)GlcNAc(2) carbohydrates bound to unfolded proteins, yielding Man(7)GlcNAc(2). This glycan serves as a signal for HRD ligase-mediated glycoprotein disposal. We identified a point mutation in PDI1 that prevents complex formation of the oxidoreductase with Htm1p, diminishes mannosidase activity, and delays degradation of unfolded glycoproteins in vivo. Our results show that Pdi1p is engaged in both recognition and glycan signal processing of ERAD substrates and suggest that protein folding and breakdown are not separated but interconnected processes. We propose a stochastic model for how a given glycoprotein is partitioned into folding or degradation pathways and how the flux through these pathways is adjusted to stress conditions.
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Affiliation(s)
- Robert Gauss
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology Zurich, 8093 Zurich, Switzerland
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28
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Cho K, Cho S, Lee SO, Oh C, Kang K, Ryoo J, Lee S, Kang S, Ahn K. Redox-regulated peptide transfer from the transporter associated with antigen processing to major histocompatibility complex class I molecules by protein disulfide isomerase. Antioxid Redox Signal 2011; 15:621-33. [PMID: 21299467 DOI: 10.1089/ars.2010.3756] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Most antigenic peptides are generated by proteasomes in the cytosol and are transported by the transporter associated with antigen processing (TAP) into the endoplasmic reticulum, where they bind with nascent major histocompatibilitiy complex class I molecule (MHC-I). Although the overall process of peptide-MHC-I complex assembly is well studied, the mechanism by which free peptides are delivered from TAP to MHC-I is unknown. In this study, we investigated the possible role of protein disulfide isomerase (PDI) as a peptide carrier between TAP and MHC-I. Analysis of PDI-peptide complexes reconstituted in vitro showed that PDI exhibits some degree of specificity for peptides corresponding to antigenic ligands of various human leukocyte antigen (HLA) alleles. Mutations of either anchor residues of the peptide ligand or the peptide-binding site of PDI inhibited the PDI-peptide interaction. The PDI-peptide interaction increased under reducing conditions, whereas binding of the peptide to PDI decreased under oxidizing conditions. TAP-associated PDI was predominantly present in the reduced form, whereas the MHC-I-associated PDI was present in the oxidized form. Further, upon binding of optimal peptides, PDI was released from TAP and sequentially associated with HLA-A2.1. Our data revealed a redox-regulated chaperone function of PDI in delivering antigenic peptides from TAP to MHC-I.
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Affiliation(s)
- Kwangmin Cho
- Department of Biological Sciences, National Creative Research Center for Antigen Presentation, Seoul National University, Seoul, South Korea
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Winter J, Gleiter S, Klappa P, Lilie H. Protein disulfide isomerase isomerizes non-native disulfide bonds in human proinsulin independent of its peptide-binding activity. Protein Sci 2011; 20:588-96. [PMID: 21308844 DOI: 10.1002/pro.592] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Protein disulfide isomerase (PDI) supports proinsulin folding as chaperone and isomerase. Here, we focus on how the two PDI functions influence individual steps in the complex folding process of proinsulin. We generated a PDI mutant (PDI-aba'c) where the b' domain was partially deleted, thus abolishing peptide binding but maintaining a PDI-like redox potential. PDI-aba'c catalyzes the folding of human proinsulin by increasing the rate of formation and the final yield of native proinsulin. Importantly, PDI-aba'c isomerizes non-native disulfide bonds in completely oxidized folding intermediates, thereby accelerating the formation of native disulfide bonds. We conclude that peptide binding to PDI is not essential for disulfide isomerization in fully oxidized proinsulin folding intermediates.
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Affiliation(s)
- Jeannette Winter
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, 85747 Garching, Germany.
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30
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Ramos MA, Mares RE, Magaña PD, Rivas ID, Meléndez-López SG. Entamoeba histolytica: Biochemical characterization of a protein disulfide isomerase. Exp Parasitol 2011; 128:76-81. [DOI: 10.1016/j.exppara.2011.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 02/05/2011] [Accepted: 02/08/2011] [Indexed: 11/29/2022]
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31
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Comparative genomic study of protein disulfide isomerases from photosynthetic organisms. Genomics 2011; 97:37-50. [DOI: 10.1016/j.ygeno.2010.10.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 09/15/2010] [Accepted: 10/07/2010] [Indexed: 11/19/2022]
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32
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Finnis CJA, Payne T, Hay J, Dodsworth N, Wilkinson D, Morton P, Saxton MJ, Tooth DJ, Evans RW, Goldenberg H, Scheiber-Mojdehkar B, Ternes N, Sleep D. High-level production of animal-free recombinant transferrin from Saccharomyces cerevisiae. Microb Cell Fact 2010; 9:87. [PMID: 21083917 PMCID: PMC3000842 DOI: 10.1186/1475-2859-9-87] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 11/17/2010] [Indexed: 11/18/2022] Open
Abstract
Background Animal-free recombinant proteins provide a safe and effective alternative to tissue or serum-derived products for both therapeutic and biomanufacturing applications. While recombinant insulin and albumin already exist to replace their human counterparts in cell culture media, until recently there has been no equivalent for serum transferrin. Results The first microbial system for the high-level secretion of a recombinant transferrin (rTf) has been developed from Saccharomyces cerevisiae strains originally engineered for the commercial production of recombinant human albumin (Novozymes' Recombumin® USP-NF) and albumin fusion proteins (Novozymes' albufuse®). A full-length non-N-linked glycosylated rTf was secreted at levels around ten-fold higher than from commonly used laboratory strains. Modification of the yeast 2 μm-based expression vector to allow overexpression of the ER chaperone, protein disulphide isomerase, further increased the secretion of rTf approximately twelve-fold in high cell density fermentation. The rTf produced was functionally equivalent to plasma-derived transferrin. Conclusions A Saccharomyces cerevisiae expression system has enabled the cGMP manufacture of an animal-free rTf for industrial cell culture application without the risk of prion and viral contamination, and provides a high-quality platform for the development of transferrin-based therapeutics.
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Affiliation(s)
- Christopher J A Finnis
- Novozymes Biopharma UK Limited, Castle Court, 59 Castle Boulevard, Nottingham NG71FD, UK.
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Analysis by two-dimensional Blue Native/SDS-PAGE of membrane protein alterations in rat soleus muscle after hindlimb unloading. Eur J Appl Physiol 2010; 110:1215-24. [DOI: 10.1007/s00421-010-1592-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2010] [Indexed: 01/03/2023]
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Endoplasmic reticulum associated protein degradation: a chaperone assisted journey to hell. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1803:694-705. [PMID: 20219571 DOI: 10.1016/j.bbamcr.2010.02.005] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Revised: 02/11/2010] [Accepted: 02/18/2010] [Indexed: 01/16/2023]
Abstract
Recognition and elimination of misfolded proteins are essential cellular processes. More than thirty percent of the cellular proteins are proteins of the secretory pathway. They fold in the lumen or membrane of the endoplasmic reticulum from where they are sorted to their site of action. The folding process, as well as any refolding after cell stress, depends on chaperone activity. In case proteins are unable to acquire their native conformation, chaperones with different substrate specificity and activity guide them to elimination. For most misfolded proteins of the endoplasmic reticulum this requires retro-translocation to the cytosol and polyubiquitylation of the misfolded protein by an endoplasmic reticulum associated machinery. Thereafter ubiquitylated proteins are guided to the proteasome for degradation. This review summarizes our up to date knowledge of chaperone classes and chaperone function in endoplasmic reticulum associated degradation of protein waste.
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35
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Mukaiyama H, Tohda H, Takegawa K. Overexpression of protein disulfide isomerases enhances secretion of recombinant human transferrin in Schizosaccharomyces pombe. Appl Microbiol Biotechnol 2009; 86:1135-43. [DOI: 10.1007/s00253-009-2393-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Revised: 11/26/2009] [Accepted: 11/28/2009] [Indexed: 01/20/2023]
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Hatahet F, Ruddock LW. Protein disulfide isomerase: a critical evaluation of its function in disulfide bond formation. Antioxid Redox Signal 2009; 11:2807-50. [PMID: 19476414 DOI: 10.1089/ars.2009.2466] [Citation(s) in RCA: 479] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Disulfide bond formation is probably involved in the biogenesis of approximately one third of human proteins. A central player in this essential process is protein disulfide isomerase or PDI. PDI was the first protein-folding catalyst reported. However, despite more than four decades of study, we still do not understand much about its physiological mechanisms of action. This review examines the published literature with a critical eye. This review aims to (a) provide background on the chemistry of disulfide bond formation and rearrangement, including the concept of reduction potential, before examining the structure of PDI; (b) detail the thiol-disulfide exchange reactions that are catalyzed by PDI in vitro, including a critical examination of the assays used to determine them; (c) examine oxidation and reduction of PDI in vivo, including not only the role of ERo1 but also an extensive assessment of the role of glutathione, as well as other systems, such as peroxide, dehydroascorbate, and a discussion of vitamin K-based systems; (d) consider the in vivo reactions of PDI and the determination and implications of the redox state of PDI in vivo; and (e) discuss other human and yeast PDI-family members.
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Affiliation(s)
- Feras Hatahet
- Department of Biochemistry, University of Oulu , Oulu, Finland
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37
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Interaction of human protein disulfide isomerase and human P5 with drug compounds: Analysis using biosensor technology. Process Biochem 2008. [DOI: 10.1016/j.procbio.2008.07.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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38
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Tian G, Kober FX, Lewandrowski U, Sickmann A, Lennarz WJ, Schindelin H. The catalytic activity of protein-disulfide isomerase requires a conformationally flexible molecule. J Biol Chem 2008; 283:33630-40. [PMID: 18815132 PMCID: PMC2586259 DOI: 10.1074/jbc.m806026200] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Indexed: 11/06/2022] Open
Abstract
Protein-disulfide isomerase (PDI) catalyzes the formation of the correct pattern of disulfide bonds in secretory proteins. A low resolution crystal structure of yeast PDI described here reveals large scale conformational changes compared with the initially reported structure, indicating that PDI is a highly flexible molecule with its catalytic domains, a and a', representing two mobile arms connected to a more rigid core composed of the b and b' domains. Limited proteolysis revealed that the linker between the a domain and the core is more susceptible to degradation than that connecting the a' domain to the core. By restricting the two arms with inter-domain disulfide bonds, the molecular flexibility of PDI, especially that of its a domain, was demonstrated to be essential for the enzymatic activity in vitro and in vivo. The crystal structure also featured a PDI dimer, and a propensity to dimerize in solution and in the ER was confirmed by cross-linking experiments and the split green fluorescent protein system. Although sedimentation studies suggested that the self-association of PDI is weak, we hypothesize that PDI exists as an interconvertible mixture of monomers and dimers in the endoplasmic reticulum due to its high abundance in this compartment.
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Affiliation(s)
- Geng Tian
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York 11794-5215, USA
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39
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Abstract
Protein folding in the endoplasmic reticulum is often associated with the formation of native disulfide bonds. Their primary function is to stabilize the folded structure of the protein, although disulfide bond formation can also play a regulatory role. Native disulfide bond formation is not trivial, so it is often the rate-limiting step of protein folding both in vivo and in vitro. Complex coordinated systems of molecular chaperones and protein folding catalysts have evolved to help proteins attain their correct folded conformation. This includes a family of enzymes involved in catalyzing thiol-disulfide exchange in the endoplasmic reticulum, the protein disulfide isomerase (PDI) family. There are now 17 reported PDI family members in the endoplasmic reticulum of human cells, but the functional differentiation of these is far from complete. Despite PDI being the first catalyst of protein folding reported, there is much that is still not known about its mechanisms of action. This review will focus on the interactions of the human PDI family members with substrates, including recent research on identifying and characterizing their substrate-binding sites and on determining their natural substrates in vivo.
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Affiliation(s)
- Feras Hatahet
- Biocenter Oulu and Department of Biochemistry, University of Oulu, Finland
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40
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Mouray E, Moutiez M, Girault S, Sergheraert C, Florent I, Grellier P. Biochemical properties and cellular localization of Plasmodium falciparum protein disulfide isomerase. Biochimie 2006; 89:337-46. [PMID: 17166645 DOI: 10.1016/j.biochi.2006.11.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Accepted: 11/02/2006] [Indexed: 11/21/2022]
Abstract
We have previously reported the isolation of a 52,000 M(r) protein (Pf52) displaying consensus sequences for thiol:disulfide oxidoreductases. Pf52 therefore represents the plasmodial protein disulfide isomerase (PDI). It has been renamed PfPDI and correlates to MAL8P1.17 in the annotated genome of P. falciparum (3D7 strain). Antibodies were raised against recombinant (His)(6)-tagged forms of PfPDI devoid of its signal peptide sequence, demonstrating a major co-localization of PfPDI with endoplasmic reticulum-resident proteins, PfBIP and PfERC, but not with the Golgi marker PfERD2. Recombinant PfPDI displayed typical biochemical functions of PDIs: oxidase/isomerase and reductase activities, as well as a chaperone-like behavior on the denaturated protein rhodanese. These activities were comparable to those measured for the purified native bovine PDI and the human recombinant PDI. The antiplasmodial compound DS61 does inhibit the recombinant PfPDI oxidase/isomerase activity but not that of the human recombinant PDI, suggesting structural differences between both enzymes. However, a discrepancy between the inhibitory activity of DS61 on the recombinant PfPDI (IC(50) of 430 microM) and its in vitro antiplasmodial activity (IC(50) of 0.1 microM) was observed, suggesting that PfPDI is not the only target of DS61. Taking into account its biochemical properties and its intracellular localization, the involvement of PfPDI in the parasite protein folding is discussed, as well as its potential for the development of alternative antimalarial chemotherapy strategies.
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Affiliation(s)
- Elisabeth Mouray
- USM 0504 Biologie Fonctionnelle des Protozoaires, EA3335, Département Régulations, Développement, Diversité Moléculaire, CP 52, Muséum National d'Histoire Naturelle, 75231 Paris cedex 05, France
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41
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Rassow J, Pfanner N. Molecular chaperones and intracellular protein translocation. Rev Physiol Biochem Pharmacol 2006; 126:199-264. [PMID: 7886379 DOI: 10.1007/bfb0049777] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- J Rassow
- Biochemisches Institut, Universität Freiburg, Germany
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Abstract
An emerging concept is that disulfide bonds can act as a dynamic scaffold to present mature proteins in different conformational and functional states on the cell surface. Two examples are the conversion of the receptor, integrin alphaIIbbeta3, from a low affinity to a high affinity state, and the interaction of CD4 receptor with the HIV-1 envelope glycoprotein gp120 to promote virus-cell fusion. In both of these cases there is a remodeling of the protein disulfide bonding pattern. The formation and rearrangement of disulfide bonds is modulated by a family of enzymes known as the thiol isomerases, which include protein disulfide isomerase (PDI), ERp5, ERp57, and ERp72. While these enzymes were reported originally to be restricted in location to the endoplasmic reticulum, in some cells thiol isomerases are found on the cell surface. This may indicate a wider role for these enzymes in cell function. In platelets it has been shown that reagents that react with cell surface sulfhydryl groups are capable of blocking a number of functional responses, including integrin-mediated aggregation, adhesion, and granule secretion. Furthermore, the use of function blocking antibodies to either PDI or ERp5 causes inhibition of these functional responses. This review summarizes current knowledge of the extracellular regulation of disulfide exchange and the implications of this in the regulation of cell function.
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Affiliation(s)
- Peter A Jordan
- School of Animal and Microbial Sciences, University of Reading, Whiteknights, Reading, United Kingdom
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43
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Kulp MS, Frickel EM, Ellgaard L, Weissman JS. Domain Architecture of Protein-disulfide Isomerase Facilitates Its Dual Role as an Oxidase and an Isomerase in Ero1p-mediated Disulfide Formation. J Biol Chem 2006; 281:876-84. [PMID: 16368681 DOI: 10.1074/jbc.m511764200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Native disulfide bond formation in eukaryotes is dependent on protein-disulfide isomerase (PDI) and its homologs, which contain varying combinations of catalytically active and inactive thioredoxin domains. However, the specific contribution of PDI to the formation of new disulfides versus reduction/rearrangement of non-native disulfides is poorly understood. We analyzed the role of individual PDI domains in disulfide bond formation in a reaction driven by their natural oxidant, Ero1p. We found that Ero1p oxidizes the isolated PDI catalytic thioredoxin domains, A and A' at the same rate. In contrast, we found that in the context of full-length PDI, there is an asymmetry in the rate of oxidation of the two active sites. This asymmetry is the result of a dual effect: an enhanced rate of oxidation of the second catalytic (A') domain and the substrate-mediated inhibition of oxidation of the first catalytic (A) domain. The specific order of thioredoxin domains in PDI is important in establishing the asymmetry in the rate of oxidation of the two active sites thus allowing A and A', two thioredoxin domains that are similar in sequence and structure, to serve opposing functional roles as a disulfide isomerase and disulfide oxidase, respectively. These findings reveal how native disulfide folding is accomplished in the endoplasmic reticulum and provide a context for understanding the proliferation of PDI homologs with combinatorial arrangements of thioredoxin domains.
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Affiliation(s)
- Mohini S Kulp
- Howard Hughes Medical Institute, Department of Cellular and Molecular Pharmacology, University of California, San Francisco, 94158, USA
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44
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Kersteen EA, Barrows SR, Raines RT. Catalysis of protein disulfide bond isomerization in a homogeneous substrate. Biochemistry 2005; 44:12168-78. [PMID: 16142915 PMCID: PMC2526094 DOI: 10.1021/bi0507985] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Protein disulfide isomerase (PDI) catalyzes the rearrangement of nonnative disulfide bonds in the endoplasmic reticulum of eukaryotic cells, a process that often limits the rate at which polypeptide chains fold into a native protein conformation. The mechanism of the reaction catalyzed by PDI is unclear. In assays involving protein substrates, the reaction appears to involve the complete reduction of some or all of its nonnative disulfide bonds followed by oxidation of the resulting dithiols. The substrates in these assays are, however, heterogeneous, which complicates mechanistic analyses. Here, we report the first analysis of disulfide bond isomerization in a homogeneous substrate. Our substrate is based on tachyplesin I, a 17-mer peptide that folds into a beta hairpin stabilized by two disulfide bonds. We describe the chemical synthesis of a variant of tachyplesin I in which its two disulfide bonds are in a nonnative state and side chains near its N and C terminus contain a fluorescence donor (tryptophan) and acceptor (N(epsilon)-dansyllysine). Fluorescence resonance energy transfer from 280 to 465 nm increases by 28-fold upon isomerization of the disulfide bonds into their native state (which has a lower E(o') = -0.313 V than does PDI). We use this continuous assay to analyze catalysis by wild-type human PDI and a variant in which the C-terminal cysteine residue within each Cys-Gly-His-Cys active site is replaced with alanine. We find that wild-type PDI catalyzes the isomerization of the substrate with kcat/K(M) = 1.7 x 10(5) M(-1) s(-1), which is the largest value yet reported for catalysis of disulfide bond isomerization. The variant, which is a poor catalyst of disulfide bond reduction and dithiol oxidation, retains virtually all of the activity of wild-type PDI in catalysis of disulfide bond isomerization. Thus, the C-terminal cysteine residues play an insignificant role in the isomerization of the disulfide bonds in nonnative tachyplesin I. We conclude that catalysis of disulfide bond isomerization by PDI does not necessarily involve a cycle of substrate reduction/oxidation.
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Affiliation(s)
- Elizabeth A Kersteen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706-1544, USA
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45
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van Anken E, Braakman I. Versatility of the endoplasmic reticulum protein folding factory. Crit Rev Biochem Mol Biol 2005; 40:191-228. [PMID: 16126486 DOI: 10.1080/10409230591008161] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The endoplasmic reticulum (ER) is dedicated to import, folding and assembly of all proteins that travel along or reside in the secretory pathway of eukaryotic cells. Folding in the ER is special. For instance, newly synthesized proteins are N-glycosylated and by default form disulfide bonds in the ER, but not elsewhere in the cell. In this review, we discuss which features distinguish the ER as an efficient folding factory, how the ER monitors its output and how it disposes of folding failures.
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Affiliation(s)
- Eelco van Anken
- Department of Cellular Protein Chemistry, Bijvoet Center, Utrecht University, The Netherlands
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46
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Horibe T, Matsui H, Tanaka M, Nagai H, Yamaguchi Y, Kato K, Kikuchi M. Gentamicin binds to the lectin site of calreticulin and inhibits its chaperone activity. Biochem Biophys Res Commun 2004; 323:281-7. [PMID: 15351734 DOI: 10.1016/j.bbrc.2004.08.099] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Indexed: 11/19/2022]
Abstract
Recently, it became clear that aminoglycoside antibiotics affect protein-protein interactions involving protein disulfide isomerase as well as protein synthesis in the endoplasmic reticulum. In this study, we used affinity column chromatography to screen gentamicin-binding proteins in microsomes derived from bovine kidney in order to learn about the possible mechanisms of gentamicin-associated nephrotoxicity. One of the gentamicin-binding proteins was identified as calreticulin (CRT) by N-terminal amino acid sequence analysis. Interestingly, gentamicin inhibited the chaperone and oxidative refolding activities of CRT when N-glycosylated substrates such as alpha1-antitrypsin and alpha-mannosidase were used as substrates, but it did not inhibit the chaperone activity of CRT when unglycosylated citrate synthase was used. Moreover, CRT suppressed the aggregation of deglycosylated and denatured alpha-mannosidase, but gentamicin did not inhibit its chaperone activity. Experiments with domain mutants suggest that the lectin site of CRT is the main target for gentamicin binding and that binding of gentamicin to this site inhibits the chaperone activity of CRT.
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Affiliation(s)
- Tomohisa Horibe
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
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Xiao R, Wilkinson B, Solovyov A, Winther JR, Holmgren A, Lundström-Ljung J, Gilbert HF. The contributions of protein disulfide isomerase and its homologues to oxidative protein folding in the yeast endoplasmic reticulum. J Biol Chem 2004; 279:49780-6. [PMID: 15377672 DOI: 10.1074/jbc.m409210200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In vitro, protein disulfide isomerase (Pdi1p) introduces disulfides into proteins (oxidase activity) and provides quality control by catalyzing the rearrangement of incorrect disulfides (isomerase activity). Protein disulfide isomerase (PDI) is an essential protein in Saccharomyces cerevisiae, but the contributions of the catalytic activities of PDI to oxidative protein folding in the endoplasmic reticulum (ER) are unclear. Using variants of Pdi1p with impaired oxidase or isomerase activity, we show that isomerase-deficient mutants of PDI support wild-type growth even in a strain in which all of the PDI homologues of the yeast ER have been deleted. Although the oxidase activity of PDI is sufficient for wild-type growth, pulse-chase experiments monitoring the maturation of carboxypeptidase Y reveal that oxidative folding is greatly compromised in mutants that are defective in isomerase activity. Pdi1p and one or more of its ER homologues (Mpd1p, Mpd2p, Eug1p, Eps1p) are required for efficient carboxypeptidase Y maturation. Consistent with its function as a disulfide isomerase in vivo, the active sites of Pdi1p are partially reduced (32 +/- 8%) in vivo. These results suggest that PDI and its ER homologues contribute both oxidase and isomerase activities to the yeast ER. The isomerase activity of PDI can be compromised without affecting growth and viability, implying that yeast proteins that are essential under laboratory conditions may not require efficient disulfide isomerization.
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Affiliation(s)
- Ruoyu Xiao
- Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030, USA
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48
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Horibe T, Iguchi D, Masuoka T, Gomi M, Kimura T, Kikuchi M. Replacement of domain b of human protein disulfide isomerase-related protein with domain b' of human protein disulfide isomerase dramatically increases its chaperone activity. FEBS Lett 2004; 566:311-5. [PMID: 15147915 DOI: 10.1016/j.febslet.2004.03.103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Revised: 03/31/2004] [Accepted: 03/31/2004] [Indexed: 10/26/2022]
Abstract
We have reported that human protein disulfide isomerase-related protein (hPDIR) has isomerase and chaperone activities that are lower than those of the human protein disulfide isomerase (hPDI), and that the b domain of hPDIR is critical for its chaperone activity [J. Biol. Chem. 279 (2004) 4604]. To investigate the basis of the differences between hPDI and hPDIR, and to determine the functions of each hPDIR domain in detail, we constructed several hPDIR domain mutants. Interestingly, when the b domain of hPDIR was replaced with the b' domain of hPDI, a dramatic increase in chaperone activity that was close to that of hPDI itself was observed. However, this mutant showed decreased oxidative refolding of alpha1-antitrypsin. The replacement of the b domain of hPDIR with the c domain of hPDI also increased its chaperone activity. These observations suggest that putative peptide-binding sites of hPDI determine both its chaperone activity and its substrate specificity.
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Affiliation(s)
- Tomohisa Horibe
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga, 525-8577, Japan
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49
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Horibe T, Gomi M, Iguchi D, Ito H, Kitamura Y, Masuoka T, Tsujimoto I, Kimura T, Kikuchi M. Different Contributions of the Three CXXC Motifs of Human Protein-disulfide Isomerase-related Protein to Isomerase Activity and Oxidative Refolding. J Biol Chem 2004; 279:4604-11. [PMID: 14627699 DOI: 10.1074/jbc.m310922200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human protein-disulfide isomerase (hPDI)-related protein (hPDIR), which we previously cloned from a human placental cDNA library (Hayano, T., and Kikuchi, M. (1995) FEBS Lett. 372, 210-214), and its mutants were expressed in the Escherichia coli pET system and purified by sequential nickel affinity resin chromatography. Three thioredoxin motifs (CXXC) of purified hPDIR were found to contribute to its isomerase activity with a rank order of CGHC > CPHC > CSMC, although both the isomerase and chaperone activities of this protein were lower than those of hPDI. Screening for hPDIR-binding proteins using a T7 phage display system revealed that alpha1-antitrypsin binds to hPDIR. Surface plasmon resonance experiments demonstrated that alpha1-antitrypsin interacts with hPDIR, but not with hPDI or human P5 (hP5). Interestingly, the rate of oxidative refolding of alpha1-antitrypsin with hPDIR was much higher than with hPDI or hP5. Thus, the substrate specificity of hPDIR differed from that associated with isomerase activity, and the contribution of the CSMC motif to the oxidative refolding of alpha1-antitrypsin was the most definite of the three (CSMC, CGHC, CPHC). Substitution of SM and PH in the CXXC motifs with GH increased isomerase activity and decreased oxidative refolding. In contrast, substitution of GH and PH with SM decreased isomerase activity and increased oxidative refolding. Because CXXC motif mutants lacking isomerase activity retain chaperone activity for the substrate rhodanese, it is clear that, similar to PDI and hP5, the isomerase and chaperone activities of hPDIR are independent. These results suggest that the central dipeptide of the CXXC motif is critical for both redox activity and substrate specificity.
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Affiliation(s)
- Tomohisa Horibe
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
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50
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Abstract
Protein disulfide isomerase (PDI) catalyzes the formation of native disulfide pairings in secretory proteins. The ability of PDI to act as a disulfide isomerase makes it an essential enzyme in eukaryotes. PDI also fulfills other important roles. Recent studies have emphasized the importance of PDI as an oxidant in the endoplasmic reticulum. Intriguing questions remain regarding how PDI is able to catalyze both isomerization and oxidation in vivo. Studies of PDI and its homologues have led to the development of small-molecule folding catalysts that are able to accelerate disulfide isomerization in vitro and in vivo. PDI will continue to provide both an inspiration for the design of such artificial foldases and a benchmark with which to gauge the success of those designs. Here, we review current understanding of the chemistry and biology of PDI, its homologues, and small molecules that mimic its catalytic activity.
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Affiliation(s)
- Elizabeth A Kersteen
- Department of Biochemistry, University of Wisconsin--Madison, Madison, WI 53706, USA
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