1
|
Li Z, Zhang R, Xu F, Yang J, Zhou L, Mao H. A Cell State Monitoring System with Integrated In Situ Imaging and pH Detection. SENSORS (BASEL, SWITZERLAND) 2023; 23:9340. [PMID: 38067713 PMCID: PMC10708649 DOI: 10.3390/s23239340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/29/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023]
Abstract
Cell models are one of the most widely used basic models in biological research, and a variety of in vitro cell culture techniques and models have been developed recently to simulate the physiological microenvironment in vivo. However, regardless of the technique or model, cell culture is the most fundamental but crucial component. As a result, we have developed a cell culture monitoring system to assess the functional status of cells within a biochip. This article focuses on a mini-microscope made from a readily available camera for in situ continuous observation of cell growth within a biochip and a pH sensor based on optoelectronic sensing for measuring pH. With the aid of this monitoring system, scientists can keep an eye on cell growth in real time and learn how the pH of the culture medium affects it. This study offers a new approach for tracking cells on biochips and serves as a valuable resource for enhancing cell culture conditions.
Collapse
Affiliation(s)
- Zening Li
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China; (Z.L.); (F.X.); (L.Z.)
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rongtao Zhang
- State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China; (R.Z.); (J.Y.)
| | - Fangliang Xu
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China; (Z.L.); (F.X.); (L.Z.)
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Yang
- State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China; (R.Z.); (J.Y.)
- Haihe Laboratory of Modern Chinese Medicine, Tianjin 301617, China
| | - Lin Zhou
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China; (Z.L.); (F.X.); (L.Z.)
| | - Hongju Mao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China; (Z.L.); (F.X.); (L.Z.)
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
2
|
Chen S, Harris M. NS5A domain I antagonises PKR to facilitate the assembly of infectious hepatitis C virus particles. PLoS Pathog 2023; 19:e1010812. [PMID: 36795772 PMCID: PMC9977016 DOI: 10.1371/journal.ppat.1010812] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 03/01/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
Hepatitis C virus NS5A is a multifunctional phosphoprotein comprised of three domains (DI, DII and DIII). DI and DII have been shown to function in genome replication, whereas DIII has a role in virus assembly. We previously demonstrated that DI in genotype 2a (JFH1) also plays a role in virus assembly, exemplified by the P145A mutant which blocked infectious virus production. Here we extend this analysis to identify two other conserved and surface exposed residues proximal to P145 (C142 and E191) that exhibited no defect in genome replication but impaired virus production. Further analysis revealed changes in the abundance of dsRNA, the size and distribution of lipid droplets (LD) and the co-localisation between NS5A and LDs in cells infected with these mutants, compared to wildtype. In parallel, to investigate the mechanism(s) underpinning this role of DI, we assessed the involvement of the interferon-induced double-stranded RNA-dependent protein kinase (PKR). In PKR-silenced cells, C142A and E191A exhibited levels of infectious virus production, LD size and co-localisation between NS5A and LD that were indistinguishable from wildtype. Co-immunoprecipitation and in vitro pulldown experiments confirmed that wildtype NS5A domain I (but not C142A or E191A) interacted with PKR. We further showed that the assembly phenotype of C142A and E191A was restored by ablation of interferon regulatory factor-1 (IRF1), a downstream effector of PKR. These data suggest a novel interaction between NS5A DI and PKR that functions to evade an antiviral pathway that blocks virus assembly through IRF1.
Collapse
Affiliation(s)
- Shucheng Chen
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
| |
Collapse
|
3
|
Gonzalez-Pastor R, Carrera-Pacheco SE, Zúñiga-Miranda J, Rodríguez-Pólit C, Mayorga-Ramos A, Guamán LP, Barba-Ostria C. Current Landscape of Methods to Evaluate Antimicrobial Activity of Natural Extracts. Molecules 2023; 28:molecules28031068. [PMID: 36770734 PMCID: PMC9920787 DOI: 10.3390/molecules28031068] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 01/24/2023] Open
Abstract
Natural extracts have been and continue to be used to treat a wide range of medical conditions, from infectious diseases to cancer, based on their convenience and therapeutic potential. Natural products derived from microbes, plants, and animals offer a broad variety of molecules and chemical compounds. Natural products are not only one of the most important sources for innovative drug development for animal and human health, but they are also an inspiration for synthetic biology and chemistry scientists towards the discovery of new bioactive compounds and pharmaceuticals. This is particularly relevant in the current context, where antimicrobial resistance has risen as a global health problem. Thus, efforts are being directed toward studying natural compounds' chemical composition and bioactive potential to generate drugs with better efficacy and lower toxicity than existing molecules. Currently, a wide range of methodologies are used to analyze the in vitro activity of natural extracts to determine their suitability as antimicrobial agents. Despite traditional technologies being the most employed, technological advances have contributed to the implementation of methods able to circumvent issues related to analysis capacity, time, sensitivity, and reproducibility. This review produces an updated analysis of the conventional and current methods to evaluate the antimicrobial activity of natural compounds.
Collapse
Affiliation(s)
- Rebeca Gonzalez-Pastor
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
| | - Saskya E. Carrera-Pacheco
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
| | - Johana Zúñiga-Miranda
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
| | - Cristina Rodríguez-Pólit
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
| | - Arianna Mayorga-Ramos
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
| | - Linda P. Guamán
- Biomedical Research Center (CENBIO), Eugenio Espejo School of Health Sciences, Universidad UTE, Quito 170527, Ecuador
- Correspondence: (L.P.G.); (C.B.-O.)
| | - Carlos Barba-Ostria
- School of Medicine, College of Health Sciences, Universidad San Francisco de Quito (USFQ), Quito 170901, Ecuador
- Correspondence: (L.P.G.); (C.B.-O.)
| |
Collapse
|
4
|
Marques M, Ferreira AR, Ribeiro D. Determining the Importance of Peroxisomal Proteins for Viral Infections in Cultured Mammalian Cells. Methods Mol Biol 2023; 2643:309-319. [PMID: 36952194 DOI: 10.1007/978-1-0716-3048-8_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
Peroxisomes have recently been shown to play important roles in the context of viral infections. However, further and more detailed studies should be performed to unravel the specific mechanisms involved. The analysis of the relevance of particular peroxisomal components, such as peroxisomal proteins, for viral infections can be performed by comparing the production of new virus particles in the absence and presence of those specific components. Different methodologies are used to quantify the production of infectious virus particles, depending on the virus, cell type, and the specific characteristics of the viral infection to be analyzed. Here we provide a detailed protocol to study the importance of a putative peroxisomal protein on infection by viruses that induce the death of their host cells. We use the influenza A virus (IAV) infection in A549 cells as a model, and the quantification of the newly produced infectious virus particles is performed by a plaque assay.
Collapse
Affiliation(s)
- Mariana Marques
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Ana Rita Ferreira
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Daniela Ribeiro
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences, University of Aveiro, Aveiro, Portugal.
| |
Collapse
|
5
|
Labisch JJ, Wiese GP, Barnes K, Bollmann F, Pflanz K. Infectious titer determination of lentiviral vectors using a temporal immunological real-time imaging approach. PLoS One 2021; 16:e0254739. [PMID: 34265014 PMCID: PMC8281989 DOI: 10.1371/journal.pone.0254739] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/01/2021] [Indexed: 11/18/2022] Open
Abstract
The analysis of the infectious titer of the lentiviral vector samples obtained during upstream and downstream processing is of major importance, however, also the most challenging method to be performed. Currently established methods like flow cytometry or qPCR lack the capability of enabling high throughput sample processing while they require a lot of manual handling. To address this limitation, we developed an immunological real-time imaging method to quantify the infectious titer of anti-CD19 CAR lentiviral vectors with a temporal readout using the Incucyte® S3 live-cell analysis system. The infective titers determined with the Incucyte® approach when compared with the flow cytometry-based assay had a lower standard deviation between replicates and a broader linear range. A major advantage of the method is the ability to obtain titer results in real-time, enabling an optimal readout time. The presented protocol significantly decreased labor and increased throughput. The ability of the assay to process high numbers of lentiviral samples in a high throughput manner was proven by performing a virus stability study, demonstrating the effects of temperature, salt, and shear stress on LV infectivity.
Collapse
Affiliation(s)
- Jennifer J. Labisch
- Lab Essentials Applications Development, Sartorius Stedim Biotech GmbH, Göttingen, Lower Saxony, Germany
- Institute of Technical Chemistry, Leibniz University Hannover, Hannover, Lower Saxony, Germany
- * E-mail:
| | - G. Philip Wiese
- Lab Essentials Applications Development, Sartorius Stedim Biotech GmbH, Göttingen, Lower Saxony, Germany
- Faculty of Mathematics, Computer Science and Natural Sciences, RWTH Aachen University, Aachen, North Rhine-Westphalia, Germany
| | - Kalpana Barnes
- BioAnalytics Applications, Essen BioScience, Royston, Hertfordshire, United Kingdom
| | - Franziska Bollmann
- Segment Marketing Viral-based Therapeutics, Sartorius Stedim Biotech GmbH, Göttingen, Lower Saxony, Germany
| | - Karl Pflanz
- Lab Essentials Applications Development, Sartorius Stedim Biotech GmbH, Göttingen, Lower Saxony, Germany
| |
Collapse
|
6
|
Fu R, Su Y, Wang R, Lin X, Jin X, Yang H, Du W, Shan X, Lv W, Huang G. Single cell capture, isolation, and long-term in-situ imaging using quantitative self-interference spectroscopy. Cytometry A 2021; 99:601-609. [PMID: 33704903 DOI: 10.1002/cyto.a.24333] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 11/09/2022]
Abstract
Single cell research with microfluidic chip is of vital importance in biomedical studies and clinical medicine. Simultaneous microfluidic cell manipulations and long-term cell monitoring needs further investigations due to the lack of label-free quantitative imaging techniques and systems. In this work, single cell capture, isolation and long-term in-situ monitoring was realized with a microfluidic cell chip, compact cell incubator and quantitative self-interference spectroscopy. The proposed imaging method could obtain quantitative and dynamic refractive index distribution in living cells. And the designed microfluidic chip could capture and isolate single cells. The customized incubator could support cell growth conditions when single cell was captured in microfluidic chip. According to the results, single cells could be trapped, transferred and pushed into the culture chamber with the microfluidic chip. The incubator could culture single cells in the chip for 120 h. The refractive index sensitivity of the proposed quantitative imaging method was 0.0282 and the relative error was merely 0.04%.
Collapse
Affiliation(s)
- Rongxin Fu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Ya Su
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Ruliang Wang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xue Lin
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xiangyu Jin
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Han Yang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Wenli Du
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xiaohui Shan
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Wenqi Lv
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Guoliang Huang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China.,National Engineering Research Center for Beijing Biochip Technology, Beijing, China
| |
Collapse
|
7
|
Shaw J, Gosain R, Kalita MM, Foster TL, Kankanala J, Mahato DR, Abas S, King BJ, Scott C, Brown E, Bentham MJ, Wetherill L, Bloy A, Samson A, Harris M, Mankouri J, Rowlands DJ, Macdonald A, Tarr AW, Fischer WB, Foster R, Griffin S. Rationally derived inhibitors of hepatitis C virus (HCV) p7 channel activity reveal prospect for bimodal antiviral therapy. eLife 2020; 9:e52555. [PMID: 33169665 PMCID: PMC7714397 DOI: 10.7554/elife.52555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/09/2020] [Indexed: 12/26/2022] Open
Abstract
Since the 1960s, a single class of agent has been licensed targeting virus-encoded ion channels, or 'viroporins', contrasting the success of channel blocking drugs in other areas of medicine. Although resistance arose to these prototypic adamantane inhibitors of the influenza A virus (IAV) M2 proton channel, a growing number of clinically and economically important viruses are now recognised to encode essential viroporins providing potential targets for modern drug discovery. We describe the first rationally designed viroporin inhibitor with a comprehensive structure-activity relationship (SAR). This step-change in understanding not only revealed a second biological function for the p7 viroporin from hepatitis C virus (HCV) during virus entry, but also enabled the synthesis of a labelled tool compound that retained biological activity. Hence, p7 inhibitors (p7i) represent a unique class of HCV antiviral targeting both the spread and establishment of infection, as well as a precedent for future viroporin-targeted drug discovery.
Collapse
Affiliation(s)
- Joseph Shaw
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Rajendra Gosain
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Monoj Mon Kalita
- Institute of Biophotonics, National Yang-Ming UniversityTaipeiTaiwan
| | - Toshana L Foster
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Jayakanth Kankanala
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - D Ram Mahato
- Institute of Biophotonics, National Yang-Ming UniversityTaipeiTaiwan
| | - Sonia Abas
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Barnabas J King
- School of Life Sciences, Faculty of Medicine & Health Sciences, University of Nottingham, Queen's Medical CentreNottinghamUnited Kingdom
| | - Claire Scott
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Emma Brown
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Matthew J Bentham
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Laura Wetherill
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Abigail Bloy
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Adel Samson
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
| | - Mark Harris
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Jamel Mankouri
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - David J Rowlands
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Andrew Macdonald
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Alexander W Tarr
- School of Life Sciences, Faculty of Medicine & Health Sciences, University of Nottingham, Queen's Medical CentreNottinghamUnited Kingdom
| | | | - Richard Foster
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
- School of Chemistry, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| | - Stephen Griffin
- Leeds Institute of Medical Research, School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University HospitalLeedsUnited Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse LaneLeedsUnited Kingdom
| |
Collapse
|
8
|
Dobson SJ, Mankouri J, Whitehouse A. Identification of potassium and calcium channel inhibitors as modulators of polyomavirus endosomal trafficking. Antiviral Res 2020; 179:104819. [PMID: 32389733 PMCID: PMC7205714 DOI: 10.1016/j.antiviral.2020.104819] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/02/2020] [Accepted: 05/04/2020] [Indexed: 12/12/2022]
Abstract
During virus entry, members of the Polyomaviridae transit the endolysosomal network en route to the endoplasmic reticulum (ER), from which degraded capsids escape into the cytoplasm and enter the nucleus. Emerging evidence suggests that viruses require both endosomal acidification and the correct ionic balance of K+ and Ca2+ ions in endosomes for correct virus trafficking and genome release. Here, using two polyomaviruses with different capsid architectures, namely Simian virus 40 (SV40) and Merkel cell polyomavirus (MCPyV), we describe methods to rapidly quantify virus infection using IncuCyte ZOOM imaging analysis, and use this system to investigate the role of both K+ and Ca2+ channels during the early stages of virus entry. Using broad spectrum blockers of both K+ and Ca2+ channels to specifically target host cell ion channel functionality, we show that MCPyV, but not SV40 can be inhibited by K+ channel modulators, whilst both viruses are restricted by the broad spectrum Ca2+ channel inhibitor verapamil. Using a panel of more specific Ca2+ blockers, we show that both MCPyV and SV40 are dependent on the activity of two-pore Ca2+ channels (TPCs), as the TPC-specific blocker tetrandrine prevented capsid disassembly and nuclear transport required for virus entry. We therefore reveal a novel target to restrict the entry of polyomaviruses, which given the known role of TPCs during endolysosomal-ER fusion, is likely to be applicable to other viruses that transit this pathway. We describe novel high-throughput assays to study SV40 and MCPyV infection. MCPyV, but not SV40, is sensitive to K+ channel inhibition. Verapamil inhibits MCPyV and SV40 infection. Tetrandrine is a potent inhibitor of MCPyV and SV40 infection. Two-pore channel 1/2 activity is essential for polyomavirus entry.
Collapse
Affiliation(s)
- Samuel J Dobson
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, United Kingdom
| | - Jamel Mankouri
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, United Kingdom; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom.
| | - Adrian Whitehouse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, United Kingdom; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom.
| |
Collapse
|
9
|
Panou MM, Antoni M, Morgan EL, Loundras EA, Wasson CW, Welberry-Smith M, Mankouri J, Macdonald A. Glibenclamide inhibits BK polyomavirus infection in kidney cells through CFTR blockade. Antiviral Res 2020; 178:104778. [PMID: 32229236 PMCID: PMC7322401 DOI: 10.1016/j.antiviral.2020.104778] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/07/2020] [Accepted: 03/18/2020] [Indexed: 02/08/2023]
Abstract
BK polyomavirus (BKPyV) is a ubiquitous pathogen in the human population that is asymptomatic in healthy individuals, but can be life-threatening in those undergoing kidney transplant. To-date, no vaccines or anti-viral therapies are available to treat human BKPyV infections. New therapeutic strategies are urgently required. In this study, using a rational pharmacological screening regimen of known ion channel modulating compounds, we show that BKPyV requires cystic fibrosis transmembrane conductance regulator (CFTR) activity to infect primary renal proximal tubular epithelial cells. Disrupting CFTR function through treatment with the clinically available drug glibenclamide, the CFTR inhibitor CFTR172, or CFTR-silencing, all reduced BKPyV infection. Specifically, time of addition assays and the assessment of the exposure of VP2/VP3 minor capsid proteins indicated a role for CFTR during BKPyV transport to the endoplasmic reticulum, an essential step during the early stages of BKPyV infection. We thus establish CFTR as an important host-factor in the BKPyV life cycle and reveal CFTR modulators as potential anti-BKPyV therapies. BK polyomavirus (BKPyV) is life-threatening in those undergoing kidney transplant. BKPyV requires CFTR to infect primary kidney cells. Disrupting CFTR function pharmacologically reduces BKPyV infection. CFTR is required during BKPyV transport to the endoplasmic reticulum.
Collapse
Affiliation(s)
- Margarita-Maria Panou
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom
| | - Michelle Antoni
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom
| | - Ethan L Morgan
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom
| | - Eleni-Anna Loundras
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom
| | - Christopher W Wasson
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom
| | | | - Jamel Mankouri
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom.
| | - Andrew Macdonald
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom.
| |
Collapse
|
10
|
Live Monitoring and Analysis of Fungal Growth, Viability, and Mycelial Morphology Using the IncuCyte NeuroTrack Processing Module. mBio 2019; 10:mBio.00673-19. [PMID: 31138745 PMCID: PMC6538782 DOI: 10.1128/mbio.00673-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pathogenic fungi remain a major cause of infectious complications in immunocompromised patients. Microscopic techniques are crucial for our understanding of fungal biology, host-pathogen interaction, and the pleiotropic effects of antifungal drugs on fungal cell growth and morphogenesis. Taking advantage of the morphological similarities of neuronal cell networks and mycelial growth patterns, we employed the IncuCyte time-lapse microscopy system and its NeuroTrack image analysis software package to study growth and branching of a variety of pathogenic yeasts and molds. Using optimized image processing definitions, we validated IncuCyte NeuroTrack analysis as a reliable and efficient tool for translational applications such as antifungal efficacy evaluation and coculture with host immune effector cells. Hence, the IncuCyte system and its NeuroTrack module provide an appealing platform for efficient in vitro studies of antifungal compounds and immunotherapeutic strategies in medical mycology. Efficient live-imaging methods are pivotal to understand fungal morphogenesis, especially as it relates to interactions with host immune cells and mechanisms of antifungal drugs. Due to the notable similarities in growth patterns of neuronal cells and mycelial networks, we sought to repurpose the NeuroTrack (NT) processing module of the IncuCyte time-lapse microscopy system as a tool to quantify mycelial growth and branching of pathogenic fungi. We showed the robustness of NT analysis to study Candida albicans and five different molds and confirmed established characteristics of mycelial growth kinetics. We also documented high intra- and interassay reproducibility of the NT module for a spectrum of spore inocula and culture periods. Using GFP-expressing Aspergillus fumigatus and Rhizopus arrhizus, the feasibility of fluorescence-based NT analysis was validated. In addition, we performed proof-of-concept experiments of NT analysis for several translational applications such as studying the morphogenesis of a filamentation-defective C. albicans mutant, the effects of different classes of antifungals (polyenes, azoles, and echinocandins), and coculture with host immune cells. High accuracy was found, even at high immune cell-to-fungus ratios or in the presence of fungal debris. For antifungal efficacy studies, addition of a cytotoxicity dye further refined IncuCyte-based analysis, facilitating real-time determination of fungistatic and fungicidal activity in a single assay. Complementing conventional MIC-based assays, NT analysis is an appealing method to study fungal morphogenesis and viability in the context of antifungal compound screening and evaluation of novel immune therapeutics.
Collapse
|
11
|
Negash AA, Olson RM, Griffin S, Gale M. Modulation of calcium signaling pathway by hepatitis C virus core protein stimulates NLRP3 inflammasome activation. PLoS Pathog 2019; 15:e1007593. [PMID: 30811485 PMCID: PMC6392285 DOI: 10.1371/journal.ppat.1007593] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 01/23/2019] [Indexed: 12/19/2022] Open
Abstract
Hepatitis C virus (HCV) infection remains a major cause of hepatic inflammation and liver disease. HCV triggers NLRP3 inflammasome activation and interleukin-1β (IL-1β) production from hepatic macrophages, or Kupffer cells, to drive the hepatic inflammatory response. Here we examined HCV activation of the NLRP3 inflammasome signaling cascade in primary human monocyte derived macrophages and THP-1 cell models of hepatic macrophages to define the HCV-specific agonist and cellular processes of inflammasome activation. We identified the HCV core protein as a virion-specific factor of inflammasome activation. The core protein was both necessary and sufficient for IL-1β production from macrophages exposed to HCV or soluble core protein alone. NLRP3 inflammasome activation by the HCV core protein required calcium mobilization linked with phospholipase-C activation. Our findings reveal a molecular basis of hepatic inflammasome activation and IL-1β release triggered by HCV core protein. This study deciphers the molecular mechanism of Hepatitis C virus (HCV)-induced hepatic inflammation. HCV triggers NLRP3 inflammasome activation and IL-1β release from hepatic macrophages, thus driving liver inflammation. Using biochemical, virological, and genetic approaches we identified the HCV core protein as the specific viral stimulus that triggers intracellular calcium signaling linked with phospholipase-C activation to drive NLRP3 inflammasome activation and IL-1β release in macrophages.
Collapse
Affiliation(s)
- Amina A. Negash
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Rebecca M. Olson
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Stephen Griffin
- School of Medicine, Faculty of Medicine and Health, University of Leeds, St James’ University Hospital, Leeds, United Kingdom
| | - Michael Gale
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
- * E-mail:
| |
Collapse
|
12
|
Wang Y, Wu W, Wu X, Sun Y, Zhang YP, Deng LX, Walker MJ, Qu W, Chen C, Liu NK, Han Q, Dai H, Shields LB, Shields CB, Sengelaub DR, Jones KJ, Smith GM, Xu XM. Remodeling of lumbar motor circuitry remote to a thoracic spinal cord injury promotes locomotor recovery. eLife 2018; 7:39016. [PMID: 30207538 PMCID: PMC6170189 DOI: 10.7554/elife.39016] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 09/09/2018] [Indexed: 12/18/2022] Open
Abstract
Retrogradely-transported neurotrophin signaling plays an important role in regulating neural circuit specificity. Here we investigated whether targeted delivery of neurotrophin-3 (NT-3) to lumbar motoneurons (MNs) caudal to a thoracic (T10) contusive spinal cord injury (SCI) could modulate dendritic patterning and synapse formation of the lumbar MNs. In vitro, Adeno-associated virus serotype two overexpressing NT-3 (AAV-NT-3) induced NT-3 expression and neurite outgrowth in cultured spinal cord neurons. In vivo, targeted delivery of AAV-NT-3 into transiently demyelinated adult mouse sciatic nerves led to the retrograde transportation of NT-3 to the lumbar MNs, significantly attenuating SCI-induced lumbar MN dendritic atrophy. NT-3 enhanced sprouting and synaptic formation of descending serotonergic, dopaminergic, and propriospinal axons on lumbar MNs, parallel to improved behavioral recovery. Thus, retrogradely transported NT-3 stimulated remodeling of lumbar neural circuitry and synaptic connectivity remote to a thoracic SCI, supporting a role for retrograde transport of NT-3 as a potential therapeutic strategy for SCI.
Collapse
Affiliation(s)
- Ying Wang
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States.,Neural Tissue Engineering Research Institute, Mudanjiang College of Medicine, Mudanjiang, China
| | - Wei Wu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Xiangbing Wu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Yan Sun
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States.,Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yi P Zhang
- Norton Neuroscience Institute, Norton Healthcare, Louisville, United States
| | - Ling-Xiao Deng
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Melissa Jane Walker
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Wenrui Qu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Chen Chen
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States.,Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indiana University School of Medicine, Indiana, United States
| | - Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Qi Han
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Heqiao Dai
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States
| | - Lisa Be Shields
- Norton Neuroscience Institute, Norton Healthcare, Louisville, United States
| | | | - Dale R Sengelaub
- Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, United States
| | - Kathryn J Jones
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, United States
| | - George M Smith
- Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, United States
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, United States.,Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, United States.,Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, United States
| |
Collapse
|
13
|
Visualisation and analysis of hepatitis C virus non-structural proteins using super-resolution microscopy. Sci Rep 2018; 8:13604. [PMID: 30206266 PMCID: PMC6134135 DOI: 10.1038/s41598-018-31861-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 08/29/2018] [Indexed: 01/17/2023] Open
Abstract
Hepatitis C virus (HCV) RNA replication occurs in the cytosol of infected cells within a specialised membranous compartment. How the viral non-structural (NS) proteins are associated and organised within these structures remains poorly defined. We employed a super-resolution microscopy approach to visualise NS3 and NS5A in HCV infected cells. Using single molecule localisation microscopy, both NS proteins were resolved as clusters of localisations smaller than the diffraction-limited volume observed by wide-field. Analysis of the protein clusters identified a significant difference in size between the NS proteins. We also observed a reduction in NS5A cluster size following inhibition of RNA replication using daclatasvir, a phenotype which was maintained in the presence of the Y93H resistance associated substitution and not observed for NS3 clusters. These results provide insight into the NS protein organisation within hepatitis C virus RNA replication complexes and the mode of action of NS5A inhibitors.
Collapse
|
14
|
Panou MM, Prescott EL, Hurdiss DL, Swinscoe G, Hollinshead M, Caller LG, Morgan EL, Carlisle L, Müller M, Antoni M, Kealy D, Ranson NA, Crump CM, Macdonald A. Agnoprotein Is an Essential Egress Factor during BK Polyomavirus Infection. Int J Mol Sci 2018; 19:ijms19030902. [PMID: 29562663 PMCID: PMC5877763 DOI: 10.3390/ijms19030902] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/16/2022] Open
Abstract
BK polyomavirus (BKPyV; hereafter referred to as BK) causes a lifelong chronic infection and is associated with debilitating disease in kidney transplant recipients. Despite its importance, aspects of the virus life cycle remain poorly understood. In addition to the structural proteins, the late region of the BK genome encodes for an auxiliary protein called agnoprotein. Studies on other polyomavirus agnoproteins have suggested that the protein may contribute to virion infectivity. Here, we demonstrate an essential role for agnoprotein in BK virus release. Viruses lacking agnoprotein fail to release from host cells and do not propagate to wild-type levels. Despite this, agnoprotein is not essential for virion infectivity or morphogenesis. Instead, agnoprotein expression correlates with nuclear egress of BK virions. We demonstrate that the agnoprotein binding partner α-soluble N-ethylmaleimide sensitive fusion (NSF) attachment protein (α-SNAP) is necessary for BK virion release, and siRNA knockdown of α-SNAP prevents nuclear release of wild-type BK virions. These data highlight a novel role for agnoprotein and begin to reveal the mechanism by which polyomaviruses leave an infected cell.
Collapse
Affiliation(s)
- Margarita-Maria Panou
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Emma L Prescott
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Daniel L Hurdiss
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Gemma Swinscoe
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Michael Hollinshead
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Laura G Caller
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Ethan L Morgan
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Louisa Carlisle
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Marietta Müller
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Michelle Antoni
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - David Kealy
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Neil A Ranson
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Colin M Crump
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Andrew Macdonald
- Faculty of Biological Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
| |
Collapse
|
15
|
A role for domain I of the hepatitis C virus NS5A protein in virus assembly. PLoS Pathog 2018; 14:e1006834. [PMID: 29352312 PMCID: PMC5792032 DOI: 10.1371/journal.ppat.1006834] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 01/31/2018] [Accepted: 12/19/2017] [Indexed: 12/12/2022] Open
Abstract
The NS5A protein of hepatitis C virus (HCV) plays roles in both virus genome replication and assembly. NS5A comprises three domains, of these domain I is believed to be involved exclusively in genome replication. In contrast, domains II and III are required for the production of infectious virus particles and are largely dispensable for genome replication. Domain I is highly conserved between HCV and related hepaciviruses, and is highly structured, exhibiting different dimeric conformations. To investigate the functions of domain I in more detail, we conducted a mutagenic study of 12 absolutely conserved and surface-exposed residues within the context of a JFH-1-derived sub-genomic replicon and infectious virus. Whilst most of these abrogated genome replication, three mutants (P35A, V67A and P145A) retained the ability to replicate but showed defects in virus assembly. P35A exhibited a modest reduction in infectivity, however V67A and P145A produced no infectious virus. Using a combination of density gradient fractionation, biochemical analysis and high resolution confocal microscopy we demonstrate that V67A and P145A disrupted the localisation of NS5A to lipid droplets. In addition, the localisation and size of lipid droplets in cells infected with these two mutants were perturbed compared to wildtype HCV. Biophysical analysis revealed that V67A and P145A abrogated the ability of purified domain I to dimerize and resulted in an increased affinity of binding to HCV 3’UTR RNA. Taken together, we propose that domain I of NS5A plays multiple roles in assembly, binding nascent genomic RNA and transporting it to lipid droplets where it is transferred to Core. Domain I also contributes to a change in lipid droplet morphology, increasing their size. This study reveals novel functions of NS5A domain I in assembly of infectious HCV and provides new perspectives on the virus lifecycle. Hepatitis C virus infects 170 million people worldwide, causing long term liver disease. Recently new therapies comprising direct-acting antivirals (DAAs), small molecule inhibitors of virus proteins, have revolutionised treatment for infected patients. Despite this, we have a limited understanding of how the virus replicates in infected liver cells. Here we identify a previously uncharacterised function of the NS5A protein–a target for one class of DAAs. NS5A is comprised of three domains–we show that the first of these (domain I) plays a role in the production of new, infectious virus particles. Previously it was thought that domain I was only involved in replicating the virus genome. Mutations in domain I perturb dimer formation, enhanced binding to the 3’ end of the virus RNA genome and prevented NS5A from interacting with lipid droplets, cellular lipid storage organelles that are required for assembly of new viruses. We propose that domain I of NS5A plays multiple roles in virus assembly. As domain I is the putative target for one class of DAAs, our observations may have implications for the as yet undefined mode of action of these compounds.
Collapse
|
16
|
Gupta S, Chan DW, Zaal KJ, Kaplan MJ. A High-Throughput Real-Time Imaging Technique To Quantify NETosis and Distinguish Mechanisms of Cell Death in Human Neutrophils. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 200:869-879. [PMID: 29196457 PMCID: PMC5760330 DOI: 10.4049/jimmunol.1700905] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 11/01/2017] [Indexed: 12/31/2022]
Abstract
Neutrophils play a key role in host defenses and have recently been implicated in the pathogenesis of autoimmune diseases by various mechanisms, including formation of neutrophil extracellular traps through a recently described distinct form of programmed cell death called NETosis. Techniques to assess and quantitate NETosis in an unbiased, reproducible, and efficient way are lacking, considerably limiting the advancement of research in this field. We optimized and validated, a new method to automatically quantify the percentage of neutrophils undergoing NETosis in real time using the IncuCyte ZOOM imaging platform and the membrane-permeability properties of two DNA dyes. Neutrophils undergoing NETosis induced by various physiological stimuli showed distinct changes, with a loss of multilobulated nuclei, as well as nuclear decondensation followed by membrane compromise, and were accurately counted by applying filters based on fluorescence intensity and nuclear size. Findings were confirmed and validated with the established method of immunofluorescence microscopy. The platform was also validated to rapidly assess and quantify the dose-dependent effect of inhibitors of NETosis. In addition, this method was able to distinguish among neutrophils undergoing NETosis, apoptosis, or necrosis based on distinct changes in nuclear morphology and membrane integrity. The IncuCyte ZOOM platform is a novel real-time assay that quantifies NETosis in a rapid, automated, and reproducible way, significantly optimizing the study of neutrophils. This platform is a powerful tool to assess neutrophil physiology and NETosis, as well as to swiftly develop and test novel neutrophil targets.
Collapse
Affiliation(s)
- Sarthak Gupta
- Systemic Autoimmunity Branch, Intramural Research Program, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892; and
| | - Diana W Chan
- Systemic Autoimmunity Branch, Intramural Research Program, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892; and
| | - Kristien J Zaal
- Light Imaging Section, Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Mariana J Kaplan
- Systemic Autoimmunity Branch, Intramural Research Program, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892; and
| |
Collapse
|
17
|
Wewer Albrechtsen NJ, Albrechtsen R, Bremholm L, Svendsen B, Kuhre RE, Poulsen SS, Christiansen CB, Jensen EP, Janus C, Hilsted L, Deacon CF, Hartmann B, Holst JJ. Glucagon-like Peptide 1 Receptor Signaling in Acinar Cells Causes Growth-Dependent Release of Pancreatic Enzymes. Cell Rep 2017; 17:2845-2856. [PMID: 27974199 DOI: 10.1016/j.celrep.2016.11.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/31/2016] [Accepted: 11/15/2016] [Indexed: 12/19/2022] Open
Abstract
Incretin-based therapies are widely used for type 2 diabetes and now also for obesity, but they are associated with elevated plasma levels of pancreatic enzymes and perhaps a modestly increased risk of acute pancreatitis. However, little is known about the effects of the incretin hormone glucagon-like peptide 1 (GLP-1) on the exocrine pancreas. Here, we identify GLP-1 receptors on pancreatic acini and analyze the impact of receptor activation in humans, rodents, isolated acini, and cell lines from the exocrine pancreas. GLP-1 did not directly stimulate amylase or lipase release. However, we saw that GLP-1 induces phosphorylation of the epidermal growth factor receptor and activation of Foxo1, resulting in cell growth with concomitant enzyme release. Our work uncovers GLP-1-induced signaling pathways in the exocrine pancreas and suggests that increases in amylase and lipase levels in subjects treated with GLP-1 receptor agonists reflect adaptive growth rather than early-stage pancreatitis.
Collapse
Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Reidar Albrechtsen
- Department of Biomedical Sciences and Biotech Research and Innovation Centre (BRIC), University of Copenhagen, 2200 Copenhagen, Denmark
| | - Lasse Bremholm
- Department of Surgery, Zealand University Hospital, Lykkebækvej 1, 4600 Køge, Denmark
| | - Berit Svendsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Steen S Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Charlotte B Christiansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Elisa P Jensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Charlotte Janus
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Linda Hilsted
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
| |
Collapse
|
18
|
Goonawardane N, Ross-Thriepland D, Harris M. Regulation of hepatitis C virus replication via threonine phosphorylation of the NS5A protein. J Gen Virol 2017; 99:62-72. [PMID: 29139348 PMCID: PMC5882090 DOI: 10.1099/jgv.0.000975] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The hepatitis C virus non-structural 5A (NS5A) protein is highly phosphorylated and plays roles in both virus genome replication and assembly of infectious virus particles. NS5A comprises three domains separated by low complexity sequences (LCS). Mass spectrometry analysis of NS5A revealed the existence of a singly phosphorylated tryptic peptide corresponding to the end of LCS I and the beginning of domain II that contained a number of potential phosphorylatable residues (serines and threonines). Here we use a mutagenic approach to investigate the potential role of three of these threonine residues. Phosphomimetic mutations of two of these (T242E and T244E) resulted in significant reductions in virus genome replication and the production of infectious virus, suggesting that the phosphorylation of these residues negatively regulated virus RNA synthesis. Mutation of T245 had no effect, however when T245E was combined with the other two phosphomimetic mutations (TripleE) the inhibitory effect on replication was less pronounced. Effects of the mutations on the ratio of basally/hyperphosphorylated NS5A, together with the apparent molecular weight of the basally phosphorylated species were also observed. Lastly, two of the mutations (T245A and TripleE) resulted in a perinuclear restricted localization of NS5A. These data add further complexity to NS5A phosphorylation and suggest that this analysis be extended outwith the serine-rich cluster within LCS I.
Collapse
Affiliation(s)
- Niluka Goonawardane
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Douglas Ross-Thriepland
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,Present address: AstraZeneca, Cambridge Biomedical Campus, Cambridge, CB20AA, UK
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| |
Collapse
|
19
|
AAV-KLF7 Promotes Descending Propriospinal Neuron Axonal Plasticity after Spinal Cord Injury. Neural Plast 2017; 2017:1621629. [PMID: 28884027 PMCID: PMC5572611 DOI: 10.1155/2017/1621629] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/27/2017] [Accepted: 06/12/2017] [Indexed: 01/16/2023] Open
Abstract
DPSN axons mediate and maintain a variety of normal spinal functions. Unsurprisingly, DPSN tracts have been shown to mediate functional recovery following SCI. KLF7 could contribute to CST axon plasticity after spinal cord injury. In the present study, we assessed whether KLF7 could effectively promote DPSN axon regeneration and synapse formation following SCI. An AAV-KLF7 construct was used to overexpress KLF7. In vitro, KLF7 and target proteins were successfully elevated and axonal outgrowth was enhanced. In vivo, young adult C57BL/6 mice received a T10 contusion followed by an AAV-KLF7 injection at the T7–9 levels above the lesion. Five weeks later, overexpression of KLF7 was expressed in DPSN. KLF7 and KLF7 target genes (NGF, TrkA, GAP43, and P0) were detectably increased in the injured spinal cord. Myelin sparring at the lesion site, DPSN axonal regeneration and synapse formation, muscle weight, motor endplate morphology, and functional parameters were all additionally improved by KLF7 treatment. Our findings suggest that KLF7 promotes DPSN axonal plasticity and the formation of synapses with motor neurons at the caudal spinal cord, leading to improved functional recovery and further supporting the potential of AAV-KLF7 as a therapeutic agent for spinal cord injury.
Collapse
|
20
|
Liu CZ, Jiao XL, Gao DQ, Xing LB, Liu H, Luo Y, Gao YT. Real-time live-cell analysis system for screening single tumor cell clones and analyzing their colony-forming ability. Shijie Huaren Xiaohua Zazhi 2017; 25:881-890. [DOI: 10.11569/wcjd.v25.i10.881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To screen single tumor cell clones and evaluating their colony-forming ability by IncuCyte ZOOM.
METHODS Primary tumor cells were isolated by differential digestion and differential adherence method. On the basis of limited dilution, dynamic real-time tracking technology and full aperture imaging technology were used to track single cell clones and evaluate their colony-formation ability.
RESULTS Six lines of primary tumor cells (TJ3ZX-02 to 07) were isolated from 30 tumor tissues, and 89 persistently proliferative tumor cell clones were screened from five primary tumor cell lines (TJ3ZX-03 to 07), of which 67 were expanded and cryopreserved. Eighteen monoclonal cell lines were excluded due to the lack of expansion ability, and 28 polyclonal cell lines were excluded because of consisting of two or more cell types as revealed by the Sequence Diagram. The analysis of clone-forming ability of two monoclonal cell strains (TJ3ZX-06-B11, TJ3ZX-07-H11) showed that the clone-forming rates for the plate method (35.17%, 13.17%) were significantly higher than those for IncuCyte ZOOM (23.13%, 5.51%) at 14 d (P < 0.05), although there was no significant difference at 21 d (35.63% and 13.22% for IncuCyte ZOOM).
CONCLUSION IncuCyte ZOOM is simple, accurate and time-saving for screening single clones and measuring their colony-forming ability.
Collapse
|
21
|
Release of Infectious Hepatitis C Virus from Huh7 Cells Occurs via a trans-Golgi Network-to-Endosome Pathway Independent of Very-Low-Density Lipoprotein Secretion. J Virol 2016; 90:7159-70. [PMID: 27226379 PMCID: PMC4984645 DOI: 10.1128/jvi.00826-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 05/23/2016] [Indexed: 12/12/2022] Open
Abstract
The release of infectious hepatitis C virus (HCV) particles from infected cells remains poorly characterized. We previously demonstrated that virus release is dependent on the endosomal sorting complex required for transport (ESCRT). Here, we show a critical role of trans-Golgi network (TGN)-endosome trafficking during the assembly, but principally the secretion, of infectious virus. This was demonstrated by both small interfering RNA (siRNA)-mediated silencing of TGN-associated adaptor proteins and a panel of dominant negative (DN) Rab GTPases involved in TGN-endosome trafficking steps. Importantly, interfering with factors critical for HCV release did not have a concomitant effect on secretion of triglycerides, ApoB, or ApoE, indicating that particles are likely released from Huh7 cells via pathways distinct from that of very-low-density lipoprotein (VLDL). Finally, we show that HCV NS2 perturbs TGN architecture, redistributing TGN membranes to closely associate with HCV core protein residing on lipid droplets. These findings support the notion that HCV hijacks TGN-endosome trafficking to facilitate particle assembly and release. Moreover, although essential for assembly and infectivity, the trafficking of mature virions is seemingly independent of host lipoproteins. IMPORTANCE The mechanisms by which infectious hepatitis C virus particles are assembled and released from the cell are poorly understood. We show that the virus subverts host cell trafficking pathways to effect the release of virus particles and disrupts the structure of the Golgi apparatus, a key cellular organelle involved in secretion. In addition, we demonstrate that the mechanisms used by the virus to exit the cell are distinct from those used by the cell to release lipoproteins, suggesting that the virus effects a unique modification to cellular trafficking pathways.
Collapse
|
22
|
Culley S, Towers GJ, Selwood DL, Henriques R, Grove J. Infection Counter: Automated Quantification of in Vitro Virus Replication by Fluorescence Microscopy. Viruses 2016; 8:v8070201. [PMID: 27455304 PMCID: PMC4974536 DOI: 10.3390/v8070201] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/01/2016] [Accepted: 07/05/2016] [Indexed: 01/24/2023] Open
Abstract
The ability to accurately and reliably quantify viral infection is essential to basic and translational virology research. Here, we describe a simple and robust automated method for using fluorescence microscopy to estimate the proportion of virally infected cells in a monolayer. We provide details of the automated analysis workflow along with a freely available open-source ImageJ plugin, Infection Counter, for performing image quantification. Using hepatitis C virus (HCV) as an example, we have experimentally verified our method, demonstrating that it is equivalent, if not better, than the established focus-forming assay. Finally, we used Infection Counter to assess the anti-HCV activity of SMBz-CsA, a non-immunosuppressive cyclosporine analogue.
Collapse
Affiliation(s)
- Siân Culley
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.
| | - Greg J Towers
- Division of Infection and Immunity, University College London, London WC1E 6BT, UK.
| | - David L Selwood
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK.
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.
| | - Joe Grove
- Division of Infection and Immunity, University College London, London WC1E 6BT, UK.
| |
Collapse
|
23
|
Loundras EA, Herod MR, Harris M, Stonehouse NJ. Foot-and-mouth disease virus genome replication is unaffected by inhibition of type III phosphatidylinositol-4-kinases. J Gen Virol 2016; 97:2221-2230. [PMID: 27323707 DOI: 10.1099/jgv.0.000527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Foot-and-mouth disease virus (FMDV) causes economically damaging infections of cloven-hooved animals, with outbreaks resulting in large financial losses to the agricultural industry. Due to the highly contagious nature of FMDV, research with infectious virus is restricted to a limited number of key facilities worldwide. FMDV sub-genomic replicons are therefore important tools for the study of viral translation and genome replication. The type III phosphatidylinositol-4-kinases (PI4Ks) are a family of enzymes that plays a key role in the production of replication complexes (viral factories) of a number of positive-sense RNA viruses and represents a potential target for novel pan-viral therapeutics. Here, we investigated whether type III PI4Ks also play a role in the FMDV life cycle, using a combination of FMDV sub-genomic replicons and bicistronic internal ribosome entry site (IRES)-containing reporter plasmids. We demonstrated that replication of the FMDV replicon was unaffected by inhibitors of either PI4KIIIα or PI4KIIIβ. However, PIK93, an inhibitor previously demonstrated to target PI4KIIIβ, did inhibit IRES-mediated protein translation. Consistent with this, cells transfected with FMDV replicons did not exhibit elevated levels of phosphatidylinositol-4-phosphate lipids. These results are therefore supportive of the hypothesis that FMDV genome replication does not require type III PI4K activity and does not activate these kinases.
Collapse
Affiliation(s)
- Eleni-Anna Loundras
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Morgan R Herod
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Nicola J Stonehouse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| |
Collapse
|
24
|
Stewart H, Bingham R, White SJ, Dykeman EC, Zothner C, Tuplin AK, Stockley PG, Twarock R, Harris M. Identification of novel RNA secondary structures within the hepatitis C virus genome reveals a cooperative involvement in genome packaging. Sci Rep 2016; 6:22952. [PMID: 26972799 PMCID: PMC4789732 DOI: 10.1038/srep22952] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 02/19/2016] [Indexed: 12/11/2022] Open
Abstract
The specific packaging of the hepatitis C virus (HCV) genome is hypothesised to be driven by Core-RNA interactions. To identify the regions of the viral genome involved in this process, we used SELEX (systematic evolution of ligands by exponential enrichment) to identify RNA aptamers which bind specifically to Core in vitro. Comparison of these aptamers to multiple HCV genomes revealed the presence of a conserved terminal loop motif within short RNA stem-loop structures. We postulated that interactions of these motifs, as well as sub-motifs which were present in HCV genomes at statistically significant levels, with the Core protein may drive virion assembly. We mutated 8 of these predicted motifs within the HCV infectious molecular clone JFH-1, thereby producing a range of mutant viruses predicted to possess altered RNA secondary structures. RNA replication and viral titre were unaltered in viruses possessing only one mutated structure. However, infectivity titres were decreased in viruses possessing a higher number of mutated regions. This work thus identified multiple novel RNA motifs which appear to contribute to genome packaging. We suggest that these structures act as cooperative packaging signals to drive specific RNA encapsidation during HCV assembly.
Collapse
MESH Headings
- Aptamers, Nucleotide/chemistry
- Aptamers, Nucleotide/genetics
- Aptamers, Nucleotide/metabolism
- Base Sequence
- Blotting, Western
- Cell Line, Tumor
- Gene Expression Regulation, Viral
- Genome, Viral/genetics
- Hepacivirus/genetics
- Hepacivirus/metabolism
- Humans
- Mutation
- Nucleic Acid Conformation
- Nucleotide Motifs/genetics
- Protein Binding
- RNA, Viral/chemistry
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- SELEX Aptamer Technique
- Viral Core Proteins/genetics
- Viral Core Proteins/metabolism
- Viral Proteins/genetics
- Viral Proteins/metabolism
- Virus Assembly/genetics
Collapse
Affiliation(s)
- H. Stewart
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - R.J. Bingham
- York Centre for Complex Systems Analysis, Departments of Mathematics and Biology, University of York, York, YO10 5DD, United Kingdom
| | - S. J. White
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - E. C. Dykeman
- York Centre for Complex Systems Analysis, Departments of Mathematics and Biology, University of York, York, YO10 5DD, United Kingdom
| | - C. Zothner
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - A. K. Tuplin
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - P. G. Stockley
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - R. Twarock
- York Centre for Complex Systems Analysis, Departments of Mathematics and Biology, University of York, York, YO10 5DD, United Kingdom
| | - M. Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| |
Collapse
|