1
|
Berg A, Berntsson RPA, Barandun J. Nematocida displodere mechanosensitive ion channel of small conductance 2 assembles into a unique 6-channel super-structure in vitro. PLoS One 2024; 19:e0301951. [PMID: 39038013 PMCID: PMC11262690 DOI: 10.1371/journal.pone.0301951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 07/09/2024] [Indexed: 07/24/2024] Open
Abstract
Mechanosensitive ion channels play an essential role in reacting to environmental signals and sustaining cell integrity by facilitating ion flux across membranes. For obligate intracellular pathogens like microsporidia, adapting to changes in the host environment is crucial for survival and propagation. Despite representing a eukaryote of extreme genome reduction, microsporidia have expanded the gene family of mechanosensitive ion channels of small conductance (mscS) through repeated gene duplication and horizontal gene transfer. All microsporidian genomes characterized to date contain mscS genes of both eukaryotic and bacterial origin. Here, we investigated the cryo-electron microscopy structure of the bacterially derived mechanosensitive ion channel of small conductance 2 (MscS2) from Nematocida displodere, an intracellular pathogen of Caenorhabditis elegans. MscS2 is the most compact MscS-like channel known and assembles into a unique superstructure in vitro with six heptameric MscS2 channels. Individual MscS2 channels are oriented in a heterogeneous manner to one another, resembling an asymmetric, flexible six-way cross joint. Finally, we show that microsporidian MscS2 still forms a heptameric membrane channel, however the extreme compaction suggests a potential new function of this MscS-like protein.
Collapse
Affiliation(s)
- Alexandra Berg
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Science for Life Laboratory, Umeå University, Umeå, Västerbotten, Sweden
- Department of Medical Biochemistry and Biophysics, Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Västerbotten, Sweden
| | - Ronnie P.-A. Berntsson
- Department of Medical Biochemistry and Biophysics, Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Västerbotten, Sweden
- Wallenberg Centre for Molecular Medicine & Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Jonas Barandun
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Science for Life Laboratory, Umeå University, Umeå, Västerbotten, Sweden
| |
Collapse
|
2
|
Tang L, Sabi MM, Fu M, Guan J, Wang Y, Xia T, Zheng K, Qu H, Han B. Host cell manipulation by microsporidia secreted effectors: Insights into intracellular pathogenesis. J Eukaryot Microbiol 2024:e13029. [PMID: 39030770 DOI: 10.1111/jeu.13029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/29/2024] [Accepted: 03/29/2024] [Indexed: 07/22/2024]
Abstract
Microsporidia are prolific producers of effector molecules, encompassing both proteins and nonproteinaceous effectors, such as toxins, small RNAs, and small peptides. These secreted effectors play a pivotal role in the pathogenicity of microsporidia, enabling them to subvert the host's innate immunity and co-opt metabolic pathways to fuel their own growth and proliferation. However, the genomes of microsporidia, despite falling within the size range of bacteria, exhibit significant reductions in both structural and physiological features, thereby affecting the repertoire of secretory effectors to varying extents. This review focuses on recent advances in understanding how microsporidia modulate host cells through the secretion of effectors, highlighting current challenges and proposed solutions in deciphering the complexities of microsporidial secretory effectors.
Collapse
Affiliation(s)
- Liyuan Tang
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Musa Makongoro Sabi
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Ming Fu
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Jingyu Guan
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Yongliang Wang
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Tian Xia
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Kai Zheng
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
| | - Hongnan Qu
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
- Shenzhen Research Institute, Shandong University, Shenzhen, Guangdong, China
| | - Bing Han
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, Shandong, China
- Shenzhen Research Institute, Shandong University, Shenzhen, Guangdong, China
| |
Collapse
|
3
|
Fayet M, Long M, Han B, Belkorchia A, Delbac F, Polonais V. New insights into Microsporidia polar tube function and invasion mechanism. J Eukaryot Microbiol 2024:e13043. [PMID: 38973152 DOI: 10.1111/jeu.13043] [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: 03/18/2024] [Revised: 05/19/2024] [Accepted: 06/10/2024] [Indexed: 07/09/2024]
Abstract
Microsporidia comprise a large phylum of single-cell and obligate intracellular parasites that can infect a wide range of invertebrate and vertebrate hosts including humans. These fungal-related parasites are characterized by a highly reduced genome, a strong energy dependence on their host, but also by their unique invasion organelle known as the polar tube which is coiled within the resistant spore. Upon appropriate environmental stimulation, the long hollow polar tube (ranging from 50 to 500 μm in length) is extruded at ultra-fast speeds (300 μm/s) from the spore acting as a harpoon-like organelle to transport and deliver the infectious material or sporoplasm into the host cell. To date, seven polar tube proteins (PTPs) with distinct localizations along the extruded polar tube have been described. For example, the specific location of PTP4 and PTP7 at the tip of the polar tube supports their role in interacting with cellular receptor(s). This chapter provides a brief overview on the current understanding of polar tube structure and dynamics of extrusion, primarily through recent advancements in cryo-tomography and 3D reconstruction. It also explores the various mechanisms used for host cell invasion. Finally, recent studies on the structure and maturation of sporoplasm and its moving through the tube are discussed.
Collapse
Affiliation(s)
- Maurine Fayet
- Laboratoire "Microorganismes: Génome et Environnement", CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Mengxian Long
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Bing Han
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Department of Pathogenic Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Abdel Belkorchia
- Laboratoire "Microorganismes: Génome et Environnement", CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Frédéric Delbac
- Laboratoire "Microorganismes: Génome et Environnement", CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Valerie Polonais
- Laboratoire "Microorganismes: Génome et Environnement", CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| |
Collapse
|
4
|
Miao Z, Liao Y, Huang X, Wang X, Liao W, Wang G. New insights into the effects of UV light on individual Nosema bombycis spores, as determined using single-cell optical approaches. Photochem Photobiol 2024; 100:596-603. [PMID: 37698249 DOI: 10.1111/php.13858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/28/2023] [Accepted: 09/01/2023] [Indexed: 09/13/2023]
Abstract
Nosema bombycis (Nb) is a pathogen causing pebrine in sericulture. Ultraviolet (UV) light exposure is a common physical disinfection method, but the mechanisms underlying UV-based disinfection have only been studied at the population level. In this study, changes in and germination of UV-irradiated spores were observed using Raman tweezers and phase-contrast imaging to evaluate the effects of UV radiation on Nb spores at the single-cell level. We found that irradiation caused the complete leakage of trehalose from individual spores. We also found that more spores leaked as the UV dose increased. There was no significant loss of intracellular biomacromolecules and no marked changes in the peaks associated with protein secondary structures. Low-dose radiation promoted spore germination and high-dose radiation decreased the germination rate, while the germination time did not undergo significant alterations. These results suggest that UV radiation disrupts the permeability of the inner membrane and alters the spore wall, thereby affecting the ability of the spore to sense and respond to extracellular stimuli, which further triggers germination and reduces or stops spore germination. This study provides new insights into the molecular mechanisms underlying conventional disinfection measures on microsporidian spores.
Collapse
Affiliation(s)
- Zhenbin Miao
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, Nanning, Guangxi, China
| | - Yanlian Liao
- Guangxi Vocational & Technical College, Nanning, Guangxi, China
| | - Xuhua Huang
- Guangxi Academy of Sericultural Sciences, Nanning, Guangxi, China
| | - Xiaochun Wang
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, Nanning, Guangxi, China
| | - Wei Liao
- Guangxi Vocational & Technical College, Nanning, Guangxi, China
| | - Guiwen Wang
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, Nanning, Guangxi, China
- Guangxi Key Laboratory of Marine Natural Products and Combinatorial Biosynthesis Chemistry, Nanning, Guangxi, China
| |
Collapse
|
5
|
Bao J, Tang Y, Chen Y, Jin J, Wang X, An G, Cao L, Zhang H, Cheng G, Pan G, Zhou Z. E. hellem Ser/Thr protein phosphatase PP1 targets the DC MAPK pathway and impairs immune functions. Life Sci Alliance 2024; 7:e202302375. [PMID: 38199846 PMCID: PMC10781585 DOI: 10.26508/lsa.202302375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/01/2024] [Accepted: 01/03/2024] [Indexed: 01/12/2024] Open
Abstract
Microsporidia are difficult to be completely eliminated once infected, and the persistence disrupts host cell functions. Here in this study, we aimed to elucidate the impairing effects and consequences of microsporidia on host DCs. Enterocytozoon hellem, one of the most commonly diagnosed zoonotic microsporidia species, was applied. In vivo models demonstrated that E. hellem-infected mice were more susceptible to further pathogenic challenges, and DCs were identified as the most affected groups of cells. In vitro assays revealed that E. hellem infection impaired DCs' immune functions, reflected by down-regulated cytokine expressions, lower extent of maturation, phagocytosis ability, and antigen presentations. E. hellem infection also detained DCs' potencies to prime and stimulate T cells; therefore, host immunities were disrupted. We found that E. hellem Ser/Thr protein phosphatase PP1 directly interacts with host p38α (MAPK14) to manipulate the p38α(MAPK14)/NFAT5 axis of the MAPK pathway. Our study is the first to elucidate the molecular mechanisms of the impairing effects of microsporidia on host DCs' immune functions. The emergence of microsporidiosis may be of great threat to public health.
Collapse
Affiliation(s)
- Jialing Bao
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Yunlin Tang
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Yebo Chen
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jiangyan Jin
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Xue Wang
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guozhen An
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Lu Cao
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Huarui Zhang
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Gong Cheng
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Medicine, Tsinghua University, Beijing, China
| | - Guoqing Pan
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Zeyang Zhou
- https://ror.org/01kj4z117 The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- https://ror.org/01kj4z117 Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| |
Collapse
|
6
|
Xin ZZ, Zhu ZQ, Chen JY, Xu YL, Zhang XT, Zhang JY. Insights into the differential molecular response of non-germinated and germinated spores of Ameson portunus in vitro by comparative transcriptome analysis. J Invertebr Pathol 2024; 203:108066. [PMID: 38246321 DOI: 10.1016/j.jip.2024.108066] [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: 11/13/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 01/23/2024]
Abstract
Ameson portunus, the recently discovered causative agent of "toothpaste disease" of pond-cultured swimming crabs in China has caused enormous economic losses in aquaculture. Understanding the process of spore germination is helpful to elucidate the molecular mechanism of its invasion of host cells. Here, we obtained mature and germinating spores by isolation and purification and in vitro stimulation, respectively. Then, non-germinated and germinated spores were subjected to the comparative transcriptomic analysis to disclose differential molecular responses of these two stages. The highest germination rate, i.e., 71.45 %, was achieved in 0.01 mol/L KOH germination solution. There were 9,609 significantly differentially expressed genes (DEGs), with 685 up-regulated and 8,924 down-regulated DEGs. The up-regulated genes were significantly enriched in ribosome pathway, and the down-regulated genes were significantly enriched in various metabolic pathways, including carbohydrate metabolism, amino acid metabolism and other metabolism. The results suggested that spores require various carbohydrates and amino acids as energy to support their life activities during germination and synthesize large amounts of ribosomal proteins to provide sites for DNA replication, transcription, translation and protein synthesis of the spores of A. portunus within the host cells. Functional genes related to spore germination, such as protein phosphatase CheZ and aquaporin, were also analyzed. The analysis of transcriptome data and identification of functional genes will help to understand the process of spore germination and invasion.
Collapse
Affiliation(s)
- Zhao-Zhe Xin
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China.
| | - Zhi-Qiang Zhu
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China.
| | - Jiu-Yang Chen
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China.
| | - Ya-Li Xu
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China.
| | - Xin-Tong Zhang
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China.
| | - Jin-Yong Zhang
- The Laboratory of Aquatic Parasitology, School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong 266237, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China.
| |
Collapse
|