1
|
Kirimoto Y, Yamano-Adachi N, Koga Y, Omasa T. Effect of co-overexpression of the cargo receptor ERGIC-53/MCFD2 on antibody production and intracellular IgG secretion in recombinant Chinese hamster ovary cells. J Biosci Bioeng 2023; 136:400-406. [PMID: 35963666 DOI: 10.1016/j.jbiosc.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 11/26/2022]
Abstract
Therapeutic antibodies are attractive biopharmaceuticals because of their high therapeutic effects, fewer side effects, and prolonged half-life in the blood. Chinese hamster ovary (CHO) cells are the most widely used host cell lines to produce therapeutic antibodies in industries. High-producing recombinant CHO cells can be established via overexpression of endogenous proteins. In this study, we focused on the intracellular traffic of an antibody-producing CHO cell line, CHO-HcD6. Assembled antibodies were accumulated in the endoplasmic reticulum (ER) in the cell. We hypothesized that the accumulation was due to the insufficient number of cargo receptors in the cell and focused on a cargo receptor, the ERGIC-53-MCFD2 complex, which transports expressed proteins from the ER to the Golgi apparatus. Overexpression of the cargo receptor transport was expected to improve antibody production. Exogenous ERGIC-53 and MCFD2 were transfected into CHO-HcD6 cells, and overexpressing CHO-HcD6 cells were constructed. As a result of overexpression, antibody productivity increased in batch cultivation. However, the chase assay results and immunofluorescence microscopic observations revealed intracellular IgG accumulation in the overexpressing cells. These results suggest that overexpression of cargo receptors not only promoted extracellular secretion but also enhanced the retention of intracellular antibodies.
Collapse
Affiliation(s)
- Yutaka Kirimoto
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Noriko Yamano-Adachi
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Manufacturing Technology Association of Biologics, 7-1-49 Minatojima-minami, Kobe, Hyogo 650-0047, Japan; Industrial Biotechnology Initiative Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuichi Koga
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Industrial Biotechnology Initiative Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takeshi Omasa
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Manufacturing Technology Association of Biologics, 7-1-49 Minatojima-minami, Kobe, Hyogo 650-0047, Japan; Industrial Biotechnology Initiative Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
2
|
Novak N, Baumann M, Friss A, Cairns V, DeMaria C, Borth N. LncRNA analysis of mAb producing CHO clones reveals marker and engineering potential. Metab Eng 2023; 78:26-40. [PMID: 37196898 DOI: 10.1016/j.ymben.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/09/2023] [Accepted: 05/14/2023] [Indexed: 05/19/2023]
Abstract
Long non-coding RNAs (lncRNAs) are a potential new cell line engineering tool for improvement of yield and stability of CHO cells. In this study, we performed RNA sequencing of mAb producer CHO clones to study the lncRNA and protein coding transcriptome in relation to productivity. First, a robust linear model was used to identify genes correlating to productivity. To unravel specific patterns in expression of these genes, we employed weighted gene coexpression analysis (WGCNA) to find coexpressed modules, looking both for lncRNAs and coding genes. There was little overlap in the genes associated with productivity between the two products studied, possibly due to the difference in absolute range of productivity between the two mAbs. Therefore, we focused on the product with higher productivity and stronger candidate lncRNAs. To evaluate their potential as engineering targets, these candidate lncRNAs were transiently overexpressed or deleted by stable CRISPR Cas9 knock out both in a high and a low productivity subclone. We found that the thus achieved expression level of the identified lncRNAs, as confirmed by qPCR, does correlate well to productivity, so that they represent good markers that may be used for early clone selection. Additionally, we found that the deletion of one tested lncRNA region decreased viable cell density (VCD), prolonged culture time and increased cell size, final titer and specific productivity per cell. These results demonstrate the feasibility and usefulness of engineering lncRNA expression in production cell lines.
Collapse
Affiliation(s)
- Neža Novak
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria; ACIB, Austrian Centre of Industrial Biotechnology, Graz, Austria
| | - Martina Baumann
- ACIB, Austrian Centre of Industrial Biotechnology, Graz, Austria
| | - Amy Friss
- Sanofi Biopharmaceutics Development, Framingham, MA, USA
| | - Victor Cairns
- Sanofi Biopharmaceutics Development, Framingham, MA, USA
| | | | - Nicole Borth
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria; ACIB, Austrian Centre of Industrial Biotechnology, Graz, Austria.
| |
Collapse
|
3
|
Spatial Proteomics Reveals Differences in the Cellular Architecture of Antibody-Producing CHO and Plasma Cell-Derived Cells. Mol Cell Proteomics 2022; 21:100278. [PMID: 35934186 PMCID: PMC9562429 DOI: 10.1016/j.mcpro.2022.100278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 07/28/2022] [Accepted: 07/30/2022] [Indexed: 01/18/2023] Open
Abstract
Most of the recombinant biotherapeutics employed today to combat severe illnesses, for example, various types of cancer or autoimmune diseases, are produced by Chinese hamster ovary (CHO) cells. To meet the growing demand of these pharmaceuticals, CHO cells are under constant development in order to enhance their stability and productivity. The last decades saw a shift from empirical cell line optimization toward rational cell engineering using a growing number of large omics datasets to alter cell physiology on various levels. Especially proteomics workflows reached new levels in proteome coverage and data quality because of advances in high-resolution mass spectrometry instrumentation. One type of workflow concentrates on spatial proteomics by usage of subcellular fractionation of organelles with subsequent shotgun mass spectrometry proteomics and machine learning algorithms to determine the subcellular localization of large portions of the cellular proteome at a certain time point. Here, we present the first subcellular spatial proteome of a CHO-K1 cell line producing high titers of recombinant antibody in comparison to the spatial proteome of an antibody-producing plasma cell-derived myeloma cell line. Both cell lines show colocalization of immunoglobulin G chains with chaperones and proteins associated in protein glycosylation within the endoplasmic reticulum compartment. However, we report differences in the localization of proteins associated to vesicle-mediated transport, transcription, and translation, which may affect antibody production in both cell lines. Furthermore, pairing subcellular localization data with protein expression data revealed elevated protein masses for organelles in the secretory pathway in plasma cell-derived MPC-11 (Merwin plasma cell tumor-11) cells. Our study highlights the potential of subcellular spatial proteomics combined with protein expression as potent workflow to identify characteristics of highly efficient recombinant protein-expressing cell lines. Data are available via ProteomeXchange with identifier PXD029115.
Collapse
|
4
|
McGraw CE, Peng D, Sandoval NR. Synthetic biology approaches: the next tools for improved protein production from CHO cells. Curr Opin Chem Eng 2020. [DOI: 10.1016/j.coche.2020.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
5
|
Berger A, Le Fourn V, Masternak J, Regamey A, Bodenmann I, Girod P, Mermod N. Overexpression of transcription factor Foxa1 and target genes remediate therapeutic protein production bottlenecks in Chinese hamster ovary cells. Biotechnol Bioeng 2020; 117:1101-1116. [PMID: 31956982 PMCID: PMC7079004 DOI: 10.1002/bit.27274] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 12/27/2019] [Accepted: 01/12/2020] [Indexed: 12/13/2022]
Abstract
Despite extensive research conducted to increase protein production from Chinese hamster ovary (CHO) cells, cellular bottlenecks often remain, hindering high yields. In this study, a transcriptomic analysis led to the identification of 32 genes that are consistently upregulated in high producer clones and thus might mediate high productivity. Candidate genes were associated with functions such as signaling, protein folding, cytoskeleton organization, and cell survival. We focused on two engineering targets, Erp27, which binds unfolded proteins and the Erp57 disulfide isomerase in the endoplasmic reticulum, and Foxa1, a pioneering transcription factor involved in organ development. Erp27 moderate overexpression increased production of an easy-to-express antibody, whereas Erp27 and Erp57 co-overexpression increased cell density, viability, and the yield of difficult-to-express proteins. Foxa1 overexpression increased cell density, cell viability, and easy- and difficult-to-express protein yields, whereas it decreased reactive oxygen species late in fed-batch cultures. Foxa1 overexpression upregulated two other candidate genes that increased the production of difficult- and/or easy-to-express proteins, namely Ca3, involved in protecting cells from oxidative stress, and Tagap, involved in signaling and cytoskeleton remodeling. Overall, several genes allowing to overcome CHO cell bottlenecks were identified, including Foxa1, which mediated multiple favorable metabolic changes that improve therapeutic protein yields.
Collapse
Affiliation(s)
- Audrey Berger
- Department of Fundamental Microbiology, Institute of BiotechnologyUniversity of LausanneLausanneSwitzerland
- Present address: Laboratory of Microsystems LMIS4Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | | | - Jacqueline Masternak
- Department of Fundamental Microbiology, Institute of BiotechnologyUniversity of LausanneLausanneSwitzerland
| | | | | | | | - Nicolas Mermod
- Department of Fundamental Microbiology, Institute of BiotechnologyUniversity of LausanneLausanneSwitzerland
| |
Collapse
|
6
|
Zhu J, Hatton D. New Mammalian Expression Systems. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2019; 165:9-50. [PMID: 28585079 DOI: 10.1007/10_2016_55] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
There are an increasing number of recombinant antibodies and proteins in preclinical and clinical development for therapeutic applications. Mammalian expression systems are key to enabling the production of these molecules, and Chinese hamster ovary (CHO) cell platforms continue to be central to delivery of the stable cell lines required for large-scale production. Increasing pressure on timelines and efficiency, further innovation of molecular formats and the shift to new production systems are driving developments of these CHO cell line platforms. The availability of genome and transcriptome data coupled with advancing gene editing tools are increasing the ability to design and engineer CHO cell lines to meet these challenges. This chapter aims to give an overview of the developments in CHO expression systems and some of the associated technologies over the past few years.
Collapse
Affiliation(s)
- Jie Zhu
- MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, USA
| | - Diane Hatton
- MedImmune, Milstein Building, Granta Park, Cambridge, CB21 6GH, UK.
| |
Collapse
|
7
|
Gutiérrez-González M, Latorre Y, Zúñiga R, Aguillón JC, Molina MC, Altamirano C. Transcription factor engineering in CHO cells for recombinant protein production. Crit Rev Biotechnol 2019; 39:665-679. [PMID: 31030575 DOI: 10.1080/07388551.2019.1605496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The continuous increase of approved biopharmaceutical products drives the development of more efficient recombinant protein expression systems. Chinese hamster ovary (CHO) cells are the mainstay for this purpose but have some drawbacks, such as low levels of expression. Several strategies have been applied to increase the productivity of CHO cells with different outcomes. Transcription factor (TF) engineering has emerged as an interesting and successful approach, as these proteins can act as master regulators; the expression and function of a TF can be controlled by small molecules, and it is possible to design tailored TFs and promoters with desired features. To date, the majority of studies have focused on the use of TFs with growth, metabolic, cell cycle or endoplasmic reticulum functions, although there is a trend to develop new, synthetic TFs. Moreover, new synthetic biological approaches are showing promising advances for the development of specific TFs, even with tailored ligand sensitivity. In this article, we summarize the strategies to increase recombinant protein expression by modulating and designing TFs and with advancements in synthetic biology. We also illustrate how this class of proteins can be used to develop more robust expression systems.
Collapse
Affiliation(s)
| | - Yesenia Latorre
- b Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso , Valparaíso , Chile
| | - Roberto Zúñiga
- a Centro de InmunoBiotecnología, Universidad de Chile , Santiago , Chile
| | | | | | - Claudia Altamirano
- b Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso , Valparaíso , Chile
| |
Collapse
|
8
|
Mortazavi M, Shokrgozar MA, Sardari S, Azadmanesh K, Mahdian R, Kaghazian H, Hosseini SN, Hedayati MH. Using chemical chaperones to increase recombinant human erythropoietin secretion in CHO cell line. Prep Biochem Biotechnol 2019; 49:535-544. [PMID: 30990119 DOI: 10.1080/10826068.2018.1479865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In recombinant protein production, over-expressed genes induce unfolded protein response (UPR), overloaded protein aggregation in endoplasmic reticulum and its expansion. In this study, we have used 16 chemicals to improve erythropoietin production in engineered CHO cells and tried to study the mechanism of reducing protein aggregation in each treatment. Endoplasmic reticulum expansion was studied through endoplasmic reticulum specific labeling with utilizing fluorescent glibenclamide and its molecular chaperones expression were studied by real-time polymerase chain reaction. The increase in the mRNA level of EPO and endoplasmic reticulum chaperones GRP78/BiP, XBP1, ATF6, and ATF4 in different chemical treatments were not related to ER expansion. On the other hand, ER expansion in beta alanine, beta cyclodextrin and taurine treatments resulted in increased EPO secretion. Dramatically increase in EPO expression in conjugated linoleic acid, spermidine, trehalose, and maltose (19, 20, 16, and 19-fold, respectively) did not increase erythropoietin productivity, but betaine which did not caused ER expansion, with minor increase in EPO gene expression increase EPO productivity. The results indicated that betaine increase EPO secretion in engineered CHO cell line without relation to ER expansion and molecular chaperones expression.
Collapse
Affiliation(s)
- Mehri Mortazavi
- a National Cell Bank of Iran (NCBI), Pasteur Institute of Iran , Tehran , Iran
| | | | - Soroush Sardari
- b Unit of Drug Design and Bioinformatics, Department of Medical Biotechnology, Biotechnology Research Center , Pasteur Institute of Iran , Tehran , Iran
| | - Kayhan Azadmanesh
- c Department of Virology , Pasteur Institute of Iran , Tehran , Iran
| | - Reza Mahdian
- d Department of Molecular Medicine , Pasteur Institute of Iran , Tehran , Iran
| | - Hooman Kaghazian
- e Department of Recombinant Biopharmaceutical Production , Pasteur Institute of Iran , Karaj , Iran
| | | | - Mohammad Hossein Hedayati
- g Department of Quality Control , Production and Research Complex, Pasteur Institute of Iran , Tehran , Iran
| |
Collapse
|
9
|
Kaneyoshi K, Uchiyama K, Onitsuka M, Yamano N, Koga Y, Omasa T. Analysis of intracellular IgG secretion in Chinese hamster ovary cells to improve IgG production. J Biosci Bioeng 2019; 127:107-113. [DOI: 10.1016/j.jbiosc.2018.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/08/2018] [Accepted: 06/20/2018] [Indexed: 02/03/2023]
|
10
|
Lu Y, Zhou Q, Han Q, Wu P, Zhang L, Zhu L, Weaver DT, Xu C, Zhang B. Inactivation of deubiquitinase CYLD enhances therapeutic antibody production in Chinese hamster ovary cells. Appl Microbiol Biotechnol 2018; 102:6081-6093. [DOI: 10.1007/s00253-018-9070-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/03/2018] [Accepted: 05/06/2018] [Indexed: 12/20/2022]
|
11
|
Tung M, Tang D, Wang SH, Zhan D, Kiplinger K, Pan S, Jing Y, Shen A, Ahyow P, Snedecor B, Gawlitzek M, Misaghi S. High Intracellular Seed Train BiP Levels Correlate With Poor Production Culture Performance in CHO Cells. Biotechnol J 2018; 13:e1700746. [PMID: 29635750 DOI: 10.1002/biot.201700746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/28/2018] [Indexed: 12/31/2022]
Abstract
Consistent cell culture performance is a prerequisite to ensure product quality consistency and achieve productivity goals for the manufacture of recombinant protein therapeutics, including monoclonal antibodies. Here a peculiar observation is reported where high levels of intracellular BiP in seed train cultures are consistently predictive of poor cell culture performance in the subsequent inoculum and production cultures for a monoclonal antibody produced in CHO cells. This investigation suggests that in this cell line the high intracellular BiP levels in the seed train are triggered by a slightly lower culture pH, which interferes with proper antibody folding and secretion. While the seed train culture does not display any obvious signs of the problem at slightly lower culture pH, inoculum trains, and production cultures sourced from these low pH seed trains display significantly lower cell growth and cell size. High intracellular BiP levels may interfere with UPR signaling, thereby hampering a proper and timely UPR response in the production media. Studies of other problematic cell lines have shown a similar correlation between intracellular BiP accumulation and poor production performance. The authors believe intracellular BiP levels in seed train should hence be low in order to increase the success rate in production.
Collapse
Affiliation(s)
- Meg Tung
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Danming Tang
- Department of Early Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Szu-Han Wang
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Dejin Zhan
- Department of Early Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Karen Kiplinger
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Shu Pan
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Yifeng Jing
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Amy Shen
- Department of Early Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Patrick Ahyow
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Brad Snedecor
- Department of Early Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Martin Gawlitzek
- Department of Late Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Shahram Misaghi
- Department of Early Stage Cell Culture, Genentech, Inc., South San Francisco, CA, 94080, USA
| |
Collapse
|
12
|
Torres M, Zúñiga R, Gutierrez M, Vergara M, Collazo N, Reyes J, Berrios J, Aguillon JC, Molina MC, Altamirano C. Mild hypothermia upregulates myc and xbp1s expression and improves anti-TNFα production in CHO cells. PLoS One 2018; 13:e0194510. [PMID: 29566086 PMCID: PMC5864046 DOI: 10.1371/journal.pone.0194510] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 02/21/2018] [Indexed: 12/31/2022] Open
Abstract
Chinese hamster ovary (CHO) cells are the most frequently used host for commercial production of therapeutic proteins. However, their low protein productivity in culture is the main hurdle to overcome. Mild hypothermia has been established as an effective strategy to enhance protein specific productivity, although the causes of such improvement still remain unclear. The self-regulation of global transcriptional regulatory factors, such as Myc and XBP1s, seems to be involved in increased the recombinant protein production at low temperature. This study evaluated the impact of low temperature in CHO cell cultures on myc and xbp1s expression and their effects on culture performance and cell metabolism. Two anti-TNFα producing CHO cell lines were selected considering two distinct phenotypes: i.e. maximum cell growth, (CN1) and maximum specific anti-TNFα production (CN2), and cultured at 37, 33 and 31°C in a batch system. Low temperature led to an increase in the cell viability, the expression of the recombinant anti-TNFα and the production of anti-TNFα both in CN1 and CN2. The higher production of anti-TNFα in CN2 was mainly associated with the large expression of anti-TNFα. Under mild hypothermia myc and xbp1s expression levels were directly correlated to the maximal viable cell density and the specific anti-TNFα productivity, respectively. Moreover, cells showed a simultaneous metabolic shift from production to consumption of lactate and from consumption to production of glutamine, which were exacerbated by reducing culture temperature and coincided with the increased anti-TNFα production. Our current results provide new insights of the regulation of myc and xbp1s in CHO cells at low temperature, and suggest that the presence and magnitude of the metabolic shift might be a relevant metabolic marker of productive cell line.
Collapse
Affiliation(s)
- Mauro Torres
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Roberto Zúñiga
- Centro de InmunoBiotecnología, Programa D. de Inmunología, Instituto de Ciencias Biomédica (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Doctorado en Química, Universidad República Oriental del Uruguay, Montevideo, Uruguay
| | - Matias Gutierrez
- Centro de InmunoBiotecnología, Programa D. de Inmunología, Instituto de Ciencias Biomédica (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Mauricio Vergara
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
- Doctorado en Química, Universidad República Oriental del Uruguay, Montevideo, Uruguay
| | - Norberto Collazo
- Centro de InmunoBiotecnología, Programa D. de Inmunología, Instituto de Ciencias Biomédica (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Juan Reyes
- Instituto de Química, Pontificia Universidad Católica de Valparaíso, Valparaiso, Chile
| | - Julio Berrios
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Juan Carlos Aguillon
- Centro de InmunoBiotecnología, Programa D. de Inmunología, Instituto de Ciencias Biomédica (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Maria Carmen Molina
- Centro de InmunoBiotecnología, Programa D. de Inmunología, Instituto de Ciencias Biomédica (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Claudia Altamirano
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
- CREAS CONICYT Regional GORE, Valparaiso, Chile
- * E-mail:
| |
Collapse
|
13
|
Chalmers F, van Lith M, Sweeney B, Cain K, Bulleid NJ. Inhibition of IRE1α-mediated XBP1 mRNA cleavage by XBP1 reveals a novel regulatory process during the unfolded protein response. Wellcome Open Res 2017; 2:36. [PMID: 29062910 PMCID: PMC5645705 DOI: 10.12688/wellcomeopenres.11764.2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2017] [Indexed: 01/23/2023] Open
Abstract
Background: The mammalian endoplasmic reticulum (ER) continuously adapts to the cellular secretory load by the activation of an unfolded protein response (UPR). This stress response results in expansion of the ER, upregulation of proteins involved in protein folding and degradation, and attenuation of protein synthesis. The response is orchestrated by three signalling pathways each activated by a specific signal transducer, either inositol requiring enzyme α (IRE1α), double-stranded RNA-activated protein kinase-like ER kinase (PERK) or activating transcription factor 6 (ATF6). Activation of IRE1α results in its oligomerisation, autophosphorylation and stimulation of its ribonuclease activity. The ribonuclease initiates the splicing of an intron from mRNA encoding the transcription factor, X-box binding protein 1 (XBP1), as well as degradation of specific mRNAs and microRNAs. Methods: To investigate the consequence of expression of exogenous XBP1, we generated a stable cell-line expressing spliced XBP1 mRNA under the control of an inducible promotor. Results: Following induction of expression, high levels of XBP1 protein were detected, which allowed upregulation of target genes in the absence of induction of the UPR. Remarkably under stress conditions, the expression of exogenous XBP1 repressed splicing of endogenous XBP1 mRNA without repressing the activation of PERK. Conclusions: These results illustrate that a feedback mechanism exists to attenuate Ire1α ribonuclease activity in the presence of XBP1.
Collapse
Affiliation(s)
- Fiona Chalmers
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marcel van Lith
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | | | | | - Neil J Bulleid
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| |
Collapse
|
14
|
Chalmers F, van Lith M, Sweeney B, Cain K, Bulleid NJ. Inhibition of IRE1α-mediated XBP1 mRNA cleavage by XBP1 reveals a novel regulatory process during the unfolded protein response. Wellcome Open Res 2017. [PMID: 29062910 DOI: 10.12688/wellcomeopenres.11764.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Background: The mammalian endoplasmic reticulum (ER) continuously adapts to the cellular secretory load by the activation of an unfolded protein response (UPR). This stress response results in expansion of the ER, upregulation of proteins involved in protein folding and degradation, and attenuation of protein synthesis. The response is orchestrated by three signalling pathways each activated by a specific signal transducer, either inositol requiring enzyme α (IRE1α), double-stranded RNA-activated protein kinase-like ER kinase (PERK) or activating transcription factor 6 (ATF6). Activation of IRE1α results in its oligomerisation, autophosphorylation and stimulation of its ribonuclease activity. The ribonuclease initiates the splicing of an intron from mRNA encoding the transcription factor, X-box binding protein 1 (XBP1), as well as degradation of specific mRNAs and microRNAs. Methods: To investigate the consequence of expression of exogenous XBP1, we generated a stable cell-line expressing spliced XBP1 mRNA under the control of an inducible promotor. Results: Following induction of expression, high levels of XBP1 protein were detected, which allowed upregulation of target genes in the absence of induction of the UPR. Remarkably under stress conditions, the expression of exogenous XBP1 repressed splicing of endogenous XBP1 mRNA without repressing the activation of PERK. Conclusions: These results illustrate that a feedback mechanism exists to attenuate Ire1α ribonuclease activity in the presence of XBP1.
Collapse
Affiliation(s)
- Fiona Chalmers
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marcel van Lith
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | | | | | - Neil J Bulleid
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| |
Collapse
|
15
|
Characterization of an In Vivo Z-DNA Detection Probe Based on a Cell Nucleus Accumulating Intrabody. Mol Biotechnol 2017; 58:585-94. [PMID: 27351554 DOI: 10.1007/s12033-016-9958-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Left-handed Z-DNA is a physiologically unstable DNA conformation, and its existence in vivo can be attributed to localized torsional distress. Despite evidence for the existence of Z-DNA in vivo, its precise role in the control of gene expression is not fully understood. Here, an in vivo probe based on an anti-Z-DNA intrabody is proposed for native Z-DNA detection. The probe was used for chromatin immunoprecipitation of potential Z-DNA-forming sequences in the human genome. One of the isolated putative Z-DNA-forming sequences was cloned upstream of a reporter gene expression cassette under control of the CMV promoter. The reporter gene encoded an antibody fragment fused to GFP. Transient co-transfection of this vector along with the Z-probe coding vector improved reporter gene expression. This improvement was demonstrated by measuring reporter gene mRNA and protein levels and the amount of fluorescence in co-transfected CHO-K1 cells. These results suggest that the presence of the anti-Z-DNA intrabody can interfere with a Z-DNA-containing reporter gene expression. Therefore, this in vivo probe for the detection of Z-DNA could be used for global correlation of Z-DNA-forming sequences and gene expression regulation.
Collapse
|
16
|
The art of CHO cell engineering: A comprehensive retrospect and future perspectives. Biotechnol Adv 2015; 33:1878-96. [DOI: 10.1016/j.biotechadv.2015.10.015] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 10/21/2015] [Accepted: 10/30/2015] [Indexed: 12/14/2022]
|