1
|
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
|
2
|
Usmani M, Coudray N, Riggi M, Raghu R, Ramchandani H, Bobe D, Kopylov M, Zhong ED, Iwasa JH, Ekiert DC, Bhabha G. Cryo-ET reveals the in situ architecture of the polar tube invasion apparatus from microsporidian parasites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.13.603322. [PMID: 39026755 PMCID: PMC11257570 DOI: 10.1101/2024.07.13.603322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Microsporidia are divergent fungal pathogens that employ a harpoon-like apparatus called the polar tube (PT) to invade host cells. The PT architecture and its association with neighboring organelles remain poorly understood. Here, we use cryo-electron tomography to investigate the structural cell biology of the PT in dormant spores from the human-infecting microsporidian species, Encephalitozoon intestinalis . Segmentation and subtomogram averaging of the PT reveal at least four layers: two protein-based layers surrounded by a membrane, and filled with a dense core. Regularly spaced protein filaments form the structural skeleton of the PT. Combining cryo-electron tomography with cellular modeling, we propose a model for the 3-dimensional organization of the polaroplast, an organelle that is continuous with the membrane layer that envelops the PT. Our results reveal the ultrastructure of the microsporidian invasion apparatus in situ , laying the foundation for understanding infection mechanisms.
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
|
Yuanlae S, Prasartset T, Reamtong O, Munkongwongsiri N, Panphloi M, Preechakul T, Suebsing R, Thitamadee S, Prachumwat A, Itsathitphaisarn O, Taengchaiyaphum S, Kasamechotchung C. Shrimp injection with dsRNA targeting the microsporidian EHP polar tube protein reduces internal and external parasite amplification. Sci Rep 2024; 14:4830. [PMID: 38413745 PMCID: PMC10899260 DOI: 10.1038/s41598-024-55400-2] [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: 10/18/2023] [Accepted: 02/22/2024] [Indexed: 02/29/2024] Open
Abstract
The microsporidian Enterocytozoon hepatopenaei (EHP) is a major threat to shrimp health worldwide. Severe EHP infections in shrimp cause growth retardation and increase susceptibility to opportunistic infections. EHP produces spores with a chitin wall that enables them to survive prolonged environmental exposure. Previous studies showed that polar tube extrusion is a prerequisite for EHP infection, such that inhibiting extrusion should prevent infection. Using a proteomic approach, polar tube protein 2 of EHP (EhPTP2) was found abundantly in protein extracts obtained from extruded spores. Using an immunofluorescent antibody against EhPTP2 for immunohistochemistry, extruded spores were found in the shrimp hepatopancreas (HP) and intestine, but not in the stomach. We hypothesized that presence of EhPTP2 might be required for successful EHP spore extrusion. To test this hypothesis, we injected EhPTP2-specific double-stranded RNA (dsRNA) and found that it significantly diminished EHP copy numbers in infected shrimp. This indicated reduced amplification of EHP-infected cells in the HP by spores released from previously infected cells. In addition, injection of the dsRNA into EHP-infected shrimp prior to their use in cohabitation with naïve shrimp significantly (p < 0.05) reduced the rate of EHP transmission to naïve shrimp. The results revealed that EhPTP2 plays a crucial role in the life cycle of EHP and that dsRNA targeting EHP mRNA can effectively reach the parasite developing in host cells. This approach is a model for future investigations to identify critical genes for EHP survival and spread as potential targets for preventative and therapeutic measures in shrimp.
Collapse
Affiliation(s)
- Satika Yuanlae
- Department of Biochemistry, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
- Center for Excellence in Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Tharinthon Prasartset
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Onrapak Reamtong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Natthinee Munkongwongsiri
- Aquatic Animal Health Research Team (AQHT), Integrative Aquaculture Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Yothi Office, Rama VI Rd., Bangkok, 10400, Thailand
| | - Muthita Panphloi
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Thanchanok Preechakul
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
- Enzyme Technology Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phaholyothin Road, Khlong Luang, Pathumthani, 12120, Thailand
| | - Rungkarn Suebsing
- Center for Excellence in Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Siripong Thitamadee
- Center for Excellence in Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
- Analytical Sciences and National Doping Test Institute, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Anuphap Prachumwat
- Aquatic Animal Health Research Team (AQHT), Integrative Aquaculture Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Yothi Office, Rama VI Rd., Bangkok, 10400, Thailand
| | - Ornchuma Itsathitphaisarn
- Department of Biochemistry, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
- Center for Excellence in Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Rama VI Rd., Bangkok, 10400, Thailand
| | - Suparat Taengchaiyaphum
- Aquatic Animal Health Research Team (AQHT), Integrative Aquaculture Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Yothi Office, Rama VI Rd., Bangkok, 10400, Thailand.
| | - Chanadda Kasamechotchung
- Department of Fisheries, Faculty of Agriculture and Natural Resources, Rajamangala University of Technology Tawan-ok, Chonburi, 20110, Thailand.
| |
Collapse
|
5
|
Lv Q, Hong L, Qi L, Chen Y, Xie Z, Liao H, Li C, Li T, Meng X, Chen J, Bao J, Wei J, Han B, Shen Q, Weiss LM, Zhou Z, Long M, Pan G. Microsporidia dressing up: the spore polaroplast transport through the polar tube and transformation into the sporoplasm membrane. mBio 2024; 15:e0274923. [PMID: 38193684 PMCID: PMC10865828 DOI: 10.1128/mbio.02749-23] [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: 10/11/2023] [Accepted: 11/30/2023] [Indexed: 01/10/2024] Open
Abstract
Microsporidia are obligate intracellular parasites that infect a wide variety of hosts including humans. Microsporidian spores possess a unique, highly specialized invasion apparatus involving the polar filament, polaroplast, and posterior vacuole. During spore germination, the polar filament is discharged out of the spore forming a hollow polar tube that transports the sporoplasm components including the nucleus into the host cell. Due to the complicated topological changes occurring in this process, the details of sporoplasm formation are not clear. Our data suggest that the limiting membrane of the nascent sporoplasm is formed by the polaroplast after microsporidian germination. Using electron microscopy and 1,1'-dioctadecyl-3,3,3',3' tetramethyl indocarbocyanine perchlorate staining, we describe that a large number of vesicles, nucleus, and other cytoplasm contents were transported out via the polar tube during spore germination, while the posterior vacuole and plasma membrane finally remained in the empty spore coat. Two Nosema bombycis sporoplasm surface proteins (NbTMP1 and NoboABCG1.1) were also found to localize in the region of the polaroplast and posterior vacuole in mature spores and in the discharged polar tube, which suggested that the polaroplast during transport through the polar tube became the limiting membrane of the sporoplasm. The analysis results of Golgi-tracker green and Golgi marker protein syntaxin 6 were also consistent with the model of the transported polaroplast derived from Golgi transformed into the nascent sporoplasm membrane.IMPORTANCEMicrosporidia, which are obligate intracellular pathogenic organisms, cause huge economic losses in agriculture and even threaten human health. The key to successful infection by the microsporidia is their unique invasion apparatus which includes the polar filament, polaroplast, and posterior vacuole. When the mature spore is activated to geminate, the polar filament uncoils and undergoes a rapid transition into the hollow polar tube that transports the sporoplasm components including the microsporidian nucleus into host cells. Details of the structural difference between the polar filament and polar tube, the process of cargo transport in extruded polar tube, and the formation of the sporoplasm membrane are still poorly understood. Herein, we verify that the polar filament evaginates to form the polar tube, which serves as a conduit for transporting the nucleus and other sporoplasm components. Furthermore, our results indicate that the transported polaroplast transforms into the sporoplasm membrane during spore germination. Our study provides new insights into the cargo transportation process of the polar tube and origin of the sporoplasm membrane, which provide important clarification of the microsporidian infection mechanism.
Collapse
Affiliation(s)
- Qing Lv
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Liuyi Hong
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Lei Qi
- Biomedical Research Center for Structural Analysis, Shandong University, Jinan, Shandong, China
| | - Yuqing Chen
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Zhengkai Xie
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Hongjie Liao
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Chunfeng Li
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Tian Li
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Xianzhi Meng
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jie Chen
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jialing Bao
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Junhong Wei
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Bing Han
- Department of Pathogenic Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Qingtao Shen
- School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Louis M. Weiss
- Department of Pathology, Albert Einstein College of Medicine, New York, USA
| | - Zeyang Zhou
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- College of Life Sciences, Chongqing Normal University, Chongqing, China
| | - Mengxian Long
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guoqing Pan
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| |
Collapse
|
6
|
Sharma H, Jespersen N, Ehrenbolger K, Carlson LA, Barandun J. Ultrastructural insights into the microsporidian infection apparatus reveal the kinetics and morphological transitions of polar tube and cargo during host cell invasion. PLoS Biol 2024; 22:e3002533. [PMID: 38422169 DOI: 10.1371/journal.pbio.3002533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 03/12/2024] [Accepted: 01/29/2024] [Indexed: 03/02/2024] Open
Abstract
During host cell invasion, microsporidian spores translocate their entire cytoplasmic content through a thin, hollow superstructure known as the polar tube. To achieve this, the polar tube transitions from a compact spring-like state inside the environmental spore to a long needle-like tube capable of long-range sporoplasm delivery. The unique mechanical properties of the building blocks of the polar tube allow for an explosive transition from compact to extended state and support the rapid cargo translocation process. The molecular and structural factors enabling this ultrafast process and the structural changes during cargo delivery are unknown. Here, we employ light microscopy and in situ cryo-electron tomography to visualize multiple ultrastructural states of the Vairimorpha necatrix polar tube, allowing us to evaluate the kinetics of its germination and characterize the underlying morphological transitions. We describe a cargo-filled state with a unique ordered arrangement of microsporidian ribosomes, which cluster along the thin tube wall, and an empty post-translocation state with a reduced diameter but a thicker wall. Together with a proteomic analysis of endogenously affinity-purified polar tubes, our work provides comprehensive data on the infection apparatus of microsporidia and uncovers new aspects of ribosome regulation and transport.
Collapse
Affiliation(s)
- Himanshu Sharma
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Science for Life Laboratory, Umeå University, Umeå, Sweden
- Department of Medical Biochemistry and Biophysics, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Wallenberg Centre for Molecular Medicine, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Nathan Jespersen
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Science for Life Laboratory, Umeå University, Umeå, Sweden
| | - Kai Ehrenbolger
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Science for Life Laboratory, Umeå University, Umeå, Sweden
- Department of Medical Biochemistry and Biophysics, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Wallenberg Centre for Molecular Medicine, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Lars-Anders Carlson
- Department of Medical Biochemistry and Biophysics, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Wallenberg Centre for Molecular Medicine, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Jonas Barandun
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Science for Life Laboratory, Umeå University, Umeå, Sweden
| |
Collapse
|
7
|
Svedberg D, Winiger RR, Berg A, Sharma H, Tellgren-Roth C, Debrunner-Vossbrinck BA, Vossbrinck CR, Barandun J. Functional annotation of a divergent genome using sequence and structure-based similarity. BMC Genomics 2024; 25:6. [PMID: 38166563 PMCID: PMC10759460 DOI: 10.1186/s12864-023-09924-y] [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: 08/27/2023] [Accepted: 12/18/2023] [Indexed: 01/04/2024] Open
Abstract
BACKGROUND Microsporidia are a large taxon of intracellular pathogens characterized by extraordinarily streamlined genomes with unusually high sequence divergence and many species-specific adaptations. These unique factors pose challenges for traditional genome annotation methods based on sequence similarity. As a result, many of the microsporidian genomes sequenced to date contain numerous genes of unknown function. Recent innovations in rapid and accurate structure prediction and comparison, together with the growing amount of data in structural databases, provide new opportunities to assist in the functional annotation of newly sequenced genomes. RESULTS In this study, we established a workflow that combines sequence and structure-based functional gene annotation approaches employing a ChimeraX plugin named ANNOTEX (Annotation Extension for ChimeraX), allowing for visual inspection and manual curation. We employed this workflow on a high-quality telomere-to-telomere sequenced tetraploid genome of Vairimorpha necatrix. First, the 3080 predicted protein-coding DNA sequences, of which 89% were confirmed with RNA sequencing data, were used as input. Next, ColabFold was used to create protein structure predictions, followed by a Foldseek search for structural matching to the PDB and AlphaFold databases. The subsequent manual curation, using sequence and structure-based hits, increased the accuracy and quality of the functional genome annotation compared to results using only traditional annotation tools. Our workflow resulted in a comprehensive description of the V. necatrix genome, along with a structural summary of the most prevalent protein groups, such as the ricin B lectin family. In addition, and to test our tool, we identified the functions of several previously uncharacterized Encephalitozoon cuniculi genes. CONCLUSION We provide a new functional annotation tool for divergent organisms and employ it on a newly sequenced, high-quality microsporidian genome to shed light on this uncharacterized intracellular pathogen of Lepidoptera. The addition of a structure-based annotation approach can serve as a valuable template for studying other microsporidian or similarly divergent species.
Collapse
Affiliation(s)
- Dennis Svedberg
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Science for Life Laboratory, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, 90187, Sweden
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, 90736, Sweden
| | - Rahel R Winiger
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Science for Life Laboratory, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, 90187, Sweden
| | - Alexandra Berg
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Science for Life Laboratory, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, 90187, Sweden
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, 90736, Sweden
| | - Himanshu Sharma
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Science for Life Laboratory, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, 90187, Sweden
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, 90736, Sweden
| | - Christian Tellgren-Roth
- Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | | | - Charles R Vossbrinck
- Department of Environmental Science, Connecticut Agricultural Experiment Station, New Haven, CT, 06504, USA
| | - Jonas Barandun
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Science for Life Laboratory, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, 90187, Sweden.
| |
Collapse
|