1
|
Yuan M, Yan J, Xun J, Chen C, Zhang Y, Wang M, Chu W, Song Z, Hu Y, Zhang S, Zhang X. Enhanced human enterovirus 71 infection by endocytosis inhibitors reveals multiple entry pathways by enterovirus causing hand-foot-and-mouth diseases. Virol J 2018; 15:1. [PMID: 29298696 PMCID: PMC5751926 DOI: 10.1186/s12985-017-0913-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 12/18/2017] [Indexed: 12/23/2022] Open
Abstract
Background Human enterovirus 71 (EV71) was previously known to enter cells through clathrin or caveolar mediated endocytic pathways. However, we observed chlorpromazine (CPZ) or dynasore (DNS), which inhibit clathrin and dynamin mediated endocytosis, did not suppress EV71 cell entry in particular cell types. So the current knowledge of entry mechanisms by EV71 is not complete. Methods Viral infection was examined by flow cytometry or end-point dilution assays. Viral entry was monitored by immunofluorescence or pseudoviral infections. Various inhibitors were utilized for manipulating endocytic pathways. Cellular proteins were knockdown by siRNA. Results CPZ and DNS did not inhibit but rather enhance viral infection in A549 cells, while they inhibited infections in other cells tested. We further found CPZ did not affect EV71 binding to target cells and failed to affect viral translation and replication, but enhanced viral entry in A549 cells. Immunofluorescence microscopy further confirmed this increased entry. Using siRNA experiment, we found that the enhancement of EV71 infection by CPZ did not require the components of clathrin mediated endocytosis. Finally, CPZ also enhanced infection by Coxackivirus A16 in A549 cells. Conclusions CPZ and DNS, previously reported as EV71 entry inhibitors, may rather lead to increased viral infection in particular cell types. CPZ and DNS increased viral entry and not other steps of viral life cycles. Therefore, our study indicated an unknown dynamin-independent entry pathway utilized by enteroviruses that cause Hand-Foot-and-Mouth Diseases. Electronic supplementary material The online version of this article (10.1186/s12985-017-0913-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Meichun Yuan
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jingjing Yan
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jingna Xun
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Chong Chen
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Yuling Zhang
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Min Wang
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Wenqi Chu
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Zhigang Song
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Yunwen Hu
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Shuye Zhang
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China. .,Key Laboratory of Medical Molecular Virology of Ministries of Education/Health, Institute of Medical Microbiology, Shanghai Medical College of Fudan University, Shanghai, China. .,Department of Scientific Research, Shanghai Emerging and Re-emerging infectious Diseases Institute, 2901 Caolang Road, Jin-Shan District, Shanghai, 201508, People's Republic of China.
| | - Xiaoyan Zhang
- Shanghai Public Health Clinical Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, China. .,Department of Scientific Research, Shanghai Emerging and Re-emerging infectious Diseases Institute, 2901 Caolang Road, Jin-Shan District, Shanghai, 201508, People's Republic of China.
| |
Collapse
|
2
|
Mondal Roy S, Sarkar M. Membrane fusion induced by small molecules and ions. J Lipids 2011; 2011:528784. [PMID: 21660306 PMCID: PMC3108104 DOI: 10.1155/2011/528784] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 01/28/2011] [Accepted: 02/25/2011] [Indexed: 01/11/2023] Open
Abstract
Membrane fusion is a key event in many biological processes. These processes are controlled by various fusogenic agents of which proteins and peptides from the principal group. The fusion process is characterized by three major steps, namely, inter membrane contact, lipid mixing forming the intermediate step, pore opening and finally mixing of inner contents of the cells/vesicles. These steps are governed by energy barriers, which need to be overcome to complete fusion. Structural reorganization of big molecules like proteins/peptides, supplies the required driving force to overcome the energy barrier of the different intermediate steps. Small molecules/ions do not share this advantage. Hence fusion induced by small molecules/ions is expected to be different from that induced by proteins/peptides. Although several reviews exist on membrane fusion, no recent review is devoted solely to small moleculs/ions induced membrane fusion. Here we intend to present, how a variety of small molecules/ions act as independent fusogens. The detailed mechanism of some are well understood but for many it is still an unanswered question. Clearer understanding of how a particular small molecule can control fusion will open up a vista to use these moleucles instead of proteins/peptides to induce fusion both in vivo and in vitro fusion processes.
Collapse
Affiliation(s)
- Sutapa Mondal Roy
- Chemical Sciences Division, Saha Institute of Nuclear Physics, Sector 1, Block AF, Bidhannagar, Kolkata 700064, India
| | - Munna Sarkar
- Chemical Sciences Division, Saha Institute of Nuclear Physics, Sector 1, Block AF, Bidhannagar, Kolkata 700064, India
| |
Collapse
|
3
|
Ryu BY, Zavorotinskaya T, Trentin B, Albritton LM. The block to membrane fusion differs with the site of ligand insertion in modified retroviral envelope proteins. J Gen Virol 2008; 89:1049-1058. [PMID: 18343849 DOI: 10.1099/vir.0.83445-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Efforts to achieve cell type-specific transduction of retroviral vectors for gene therapy have centred on modification of the envelope protein (Env). Typically, addition of a ligand to Env gives binding to the new or target receptor, but little or no infection, and affects the subunit association of the modified Env. We previously discovered two point mutations that increase targeted infection by over 1000-fold when added to an Env modified by N-terminal insertion of the receptor-binding domain from amphotropic murine leukemia virus Env. Here, we asked whether these mutations would similarly increase transduction by Env modified with a clinically relevant ligand, human interleukin-13 (IL-13L). Addition of the point mutations stabilized the weak subunit association observed in some IL-13L-modified Env proteins, but infection via the target IL-13 receptor still did not occur. Fluorescence-based cell-cell fusion assays and studies with a membrane-curving agent revealed that defects in membrane fusion differed with the site of ligand insertion. When IL-13 was inserted into the N terminus of Env, membrane fusion was blocked prior to membrane-lipid mixing, regardless of whether flanking flexible linkers were added. Unexpectedly, insertion of IL-13 in the proline-rich region showed evidence of initiation of fusion and fusion-peptide exposure, but fusion was blocked at a subsequent step prior to fusion-pore formation. Thus, the site of ligand insertion influenced initiation of membrane fusion and its progression. These observations suggest that a novel site for ligand insertion must be identified before clinically useful targeted transduction will be achieved.
Collapse
Affiliation(s)
- Byoung Y Ryu
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Tatiana Zavorotinskaya
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Bernadette Trentin
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Lorraine M Albritton
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| |
Collapse
|