1
|
Huang Q, Hu W, Meng X, Chen J, Pan G. Nosema bombycis: A remarkable unicellular parasite infecting insects. J Eukaryot Microbiol 2024:e13045. [PMID: 39095558 DOI: 10.1111/jeu.13045] [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: 05/10/2024] [Revised: 06/12/2024] [Accepted: 06/17/2024] [Indexed: 08/04/2024]
Abstract
Microsporidia are opportunistic fungal-like pathogens that cause microsporidiosis, which results in significant economic losses and threatens public health. Infection of domesticated silkworms by the microsporidium Nosema bombycis causes pébrine disease, for which this species of microsporidia has received much attention. Research has been conducted extensively on this microsporidium over the past few decades to better understand its infection, transmission, host-parasite interaction, and detection. Several tools exist to study this species including the complete genome sequence of N. bombycis. In addition to the understanding of N. bombycis being important for the silkworm industry, this species has become a model organism for studying microsporidia. Research on biology of N. bombycis will contribute to the development of knowledge regarding microsporidia and potential antimicrosporidia drugs. Furthermore, this will provide insight into the molecular evolution and functioning of other fungal pathogens.
Collapse
Affiliation(s)
- Qingyuan Huang
- State Key Laboratory of Resource Insects, Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Wanying Hu
- State Key Laboratory of Resource Insects, Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Xianzhi Meng
- State Key Laboratory of Resource Insects, Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Jie Chen
- State Key Laboratory of Resource Insects, Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guoqing Pan
- State Key Laboratory of Resource Insects, Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| |
Collapse
|
2
|
Peyretaillade E, Akossi RF, Tournayre J, Delbac F, Wawrzyniak I. How to overcome constraints imposed by microsporidian genome features to ensure gene prediction? J Eukaryot Microbiol 2024:e13038. [PMID: 38934348 DOI: 10.1111/jeu.13038] [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: 06/03/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024]
Abstract
Since the advent of sequencing techniques and due to their continuous evolution, it has become easier and less expensive to obtain the complete genome sequence of any organism. Nevertheless, to elucidate all biological processes governing organism development, quality annotation is essential. In genome annotation, predicting gene structure is one of the most important and captivating challenges for computational biology. This aspect of annotation requires continual optimization, particularly for genomes as unusual as those of microsporidia. Indeed, this group of fungal-related parasites exhibits specific features (highly reduced gene sizes, sequences with high rate of evolution) linked to their evolution as intracellular parasites, requiring the implementation of specific annotation approaches to consider all these features. This review aimed to outline these characteristics and to assess the increasingly efficient approaches and tools that have enhanced the accuracy of gene prediction for microsporidia, both in terms of sensitivity and specificity. Subsequently, a final part will be dedicated to postgenomic approaches aimed at reinforcing the annotation data generated by prediction software. These approaches include the characterization of other understudied genes, such as those encoding regulatory noncoding RNAs or very small proteins, which also play crucial roles in the life cycle of these microorganisms.
Collapse
Affiliation(s)
| | - Reginal F Akossi
- LMGE, CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Jérémy Tournayre
- INRAE, UMR Herbivores, Université Clermont Auvergne, VetAgro Sup, Saint-Genès-Champanelle, France
| | - Frédéric Delbac
- LMGE, CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Ivan Wawrzyniak
- LMGE, CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
| |
Collapse
|
3
|
Tournayre J, Polonais V, Wawrzyniak I, Akossi RF, Parisot N, Lerat E, Delbac F, Souvignet P, Reichstadt M, Peyretaillade E. MicroAnnot: A Dedicated Workflow for Accurate Microsporidian Genome Annotation. Int J Mol Sci 2024; 25:880. [PMID: 38255958 PMCID: PMC10815200 DOI: 10.3390/ijms25020880] [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: 10/27/2023] [Revised: 12/29/2023] [Accepted: 01/04/2024] [Indexed: 01/24/2024] Open
Abstract
With nearly 1700 species, Microsporidia represent a group of obligate intracellular eukaryotes with veterinary, economic and medical impacts. To help understand the biological functions of these microorganisms, complete genome sequencing is routinely used. Nevertheless, the proper prediction of their gene catalogue is challenging due to their taxon-specific evolutionary features. As innovative genome annotation strategies are needed to obtain a representative snapshot of the overall lifestyle of these parasites, the MicroAnnot tool, a dedicated workflow for microsporidian sequence annotation using data from curated databases of accurately annotated microsporidian genes, has been developed. Furthermore, specific modules have been implemented to perform small gene (<300 bp) and transposable element identification. Finally, functional annotation was performed using the signature-based InterProScan software. MicroAnnot's accuracy has been verified by the re-annotation of four microsporidian genomes for which structural annotation had previously been validated. With its comparative approach and transcriptional signal identification method, MicroAnnot provides an accurate prediction of translation initiation sites, an efficient identification of transposable elements, as well as high specificity and sensitivity for microsporidian genes, including those under 300 bp.
Collapse
Affiliation(s)
- Jérémy Tournayre
- INRAE, UMR Herbivores, Université Clermont Auvergne, VetAgro Sup, 63122 Saint-Genès-Champanelle, France; (J.T.); (P.S.); (M.R.)
| | - Valérie Polonais
- LMGE, CNRS, Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (V.P.); (I.W.); (R.F.A.); (F.D.)
| | - Ivan Wawrzyniak
- LMGE, CNRS, Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (V.P.); (I.W.); (R.F.A.); (F.D.)
| | - Reginald Florian Akossi
- LMGE, CNRS, Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (V.P.); (I.W.); (R.F.A.); (F.D.)
| | - Nicolas Parisot
- UMR 203, BF2I, INRAE, INSA Lyon, Université de Lyon, 69621 Villeurbanne, France
| | - Emmanuelle Lerat
- VAS, CNRS, UMR5558, LBBE, Université Claude Bernard Lyon 1, 69622 Villeurbanne, France;
| | - Frédéric Delbac
- LMGE, CNRS, Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (V.P.); (I.W.); (R.F.A.); (F.D.)
| | - Pierre Souvignet
- INRAE, UMR Herbivores, Université Clermont Auvergne, VetAgro Sup, 63122 Saint-Genès-Champanelle, France; (J.T.); (P.S.); (M.R.)
| | - Matthieu Reichstadt
- INRAE, UMR Herbivores, Université Clermont Auvergne, VetAgro Sup, 63122 Saint-Genès-Champanelle, France; (J.T.); (P.S.); (M.R.)
| | - Eric Peyretaillade
- LMGE, CNRS, Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (V.P.); (I.W.); (R.F.A.); (F.D.)
| |
Collapse
|
4
|
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
|
5
|
Xu Y, Tang Y, Feng W, Yang Y, Cui Z. Comparative Analysis of Transposable Elements Reveals the Diversity of Transposable Elements in Decapoda and Their Effects on Genomic Evolution. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2023; 25:1136-1146. [PMID: 37923816 DOI: 10.1007/s10126-023-10265-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 10/17/2023] [Indexed: 11/06/2023]
Abstract
Transposable elements (TEs) are mobile genetic elements that exist in the host genome and exert considerable influence on the evolution of the host genome. Since crustaceans, including decapoda, are considered ideal models for studying the relationship between adaptive evolution and TEs, TEs were identified and classified in the genomes of eight decapoda species and one diplostraca species (as the outgroup) using two strategies, namely homology-based annotation and de novo annotation. The statistics and classification of TEs showed that their proportion in the genome and their taxonomic composition in decapoda were different. Moreover, correlation analysis and transcriptome data demonstrated that there were more PIF-Harbinger TEs in the genomes of Eriocheir sinensis and Scylla paramamosain, and the expression patterns of PIF-Harbingers were significantly altered under air exposure stress conditions. These results signaled that PIF-Harbingers expanded in the genome of E. sinensis and S. paramamosain and might be related to their air exposure tolerance levels. Meanwhile, sequence alignment revealed that some Jockey-like sequences (JLSs) with high similarity to specific regions of the White spot syndrome virus (WSSV) genome existed in all eight decapod species. At the same time, phylogenetic comparison exposed that the phylogenetic tree constructed by JLSs was not in agreement with that of the species tree, and the distribution of each branch was significantly different. The abovementioned results signaled that these WSSV-specific JLSs might transfer horizontally and contribute to the emergence of WSSV. This study accumulated data for expanding research on TEs in decapod species and also provided new insights and future direction for the breeding of stress-resistant and disease-resistant crab breeds.
Collapse
Affiliation(s)
- Yuanfeng Xu
- School of Marine Sciences, Ningbo University, Ningbo, 315020, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Yongkai Tang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Wenrong Feng
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, 214081, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Yanan Yang
- School of Marine Sciences, Ningbo University, Ningbo, 315020, China.
| | - Zhaoxia Cui
- School of Marine Sciences, Ningbo University, Ningbo, 315020, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| |
Collapse
|
6
|
Angst P, Pombert JF, Ebert D, Fields PD. Near chromosome-level genome assembly of the microsporidium Hamiltosporidium tvaerminnensis. G3 (BETHESDA, MD.) 2023; 13:jkad185. [PMID: 37565496 PMCID: PMC10542269 DOI: 10.1093/g3journal/jkad185] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 08/05/2023] [Indexed: 08/12/2023]
Abstract
Microsporidia are intracellular parasitic fungi whose genomes rank among the smallest of all known eukaryotes. A number of outstanding questions remain concerning the evolution of their large-scale variation in genome architecture, responsible for genome size variation of more than an order of magnitude. This genome report presents the first near-chromosomal assembly of a large-genome microsporidium, Hamiltosporidium tvaerminnensis. Combined Oxford Nanopore, Pacific Biosciences (PacBio), and Illumina sequencing led to a genome assembly of 17 contigs, 11 of which represent complete chromosomes. Our assembly is 21.64 Mb in length, has an N50 of 1.44 Mb, and consists of 39.56% interspersed repeats. We introduce a novel approach in microsporidia, PacBio Iso-Seq, as part of a larger annotation pipeline for obtaining high-quality annotations of 3,573 protein-coding genes. Based on direct evidence from the full-length Iso-Seq transcripts, we present evidence for alternative polyadenylation and variation in splicing efficiency, which are potential regulation mechanisms for gene expression in microsporidia. The generated high-quality genome assembly is a necessary resource for comparative genomics that will help elucidate the evolution of genome architecture in response to intracellular parasitism.
Collapse
Affiliation(s)
- Pascal Angst
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | | | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| |
Collapse
|
7
|
Akossi RF, Delbac F, El Alaoui H, Wawrzyniak I, Peyretaillade E. The intracellular parasite Anncaliia algerae induces a massive miRNA down-regulation in human cells. Noncoding RNA Res 2023; 8:363-375. [PMID: 37275245 PMCID: PMC10238475 DOI: 10.1016/j.ncrna.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/27/2023] [Accepted: 05/07/2023] [Indexed: 06/07/2023] Open
Abstract
Anncaliia algerae belongs to microsporidia, a group of obligate intracellular parasites related to fungi. These parasites are largely spread in water and food-webs and can infect a wide variety of hosts ranging from invertebrates to vertebrates including humans. In humans, microsporidian infections are mainly opportunistic as immunocompetent hosts can clear parasites naturally. Recent studies however have reported persistent microsporidian infections and have highlighted them as a risk factor in colon cancer. This may be a direct result of cell infection or may be an indirect effect of the infectious microenvironment and the host's response. In both cases, this raises the question of the effects of microsporidian infection at the host and host-cell levels. We aimed to address the question of human host intracellular response to microsporidian infection through a transcriptomic kinetic study of human foreskin fibroblasts (HFF) infected with A.algerae, a human infecting microsporidia with an exceptionally wide host range. We focused solely on host response studying both coding and small non-coding miRNA expression. Our study revealed a generalized down-regulation of cell miRNAs throughout infection with up to 547 different miRNAs downregulated at some timepoints and also transcriptomic dysregulations that could facilitate parasite development with immune and lipid metabolism genes modulation. We also hypothesize possible small nucleic acid expropriation explaining the miRNA downregulation. This work contributes to a better understanding of the dialogue that can occur between an intracellular parasite and its host at the cellular level, and can guide future studies on microsporidian infection biology to unravel the mode of action of these minimalist parasites at the tissue or host levels.We have also generated a kinetic and comprehensive transcriptomic data set of an infectious process that can help support comparative studies in the broader field of parasitology. Lastly, these results may warrant for caution regarding microsporidian exposure and persistent infections.
Collapse
Affiliation(s)
- Reginald Florian Akossi
- Laboratoire “Microorganismes: Génome et Environnement” (LMGE), UMR 6023, Université Clermont Auvergne and CNRS, F-63000, Clermont-Ferrand, France
| | - Fréderic Delbac
- Laboratoire “Microorganismes: Génome et Environnement” (LMGE), UMR 6023, Université Clermont Auvergne and CNRS, F-63000, Clermont-Ferrand, France
| | - Hicham El Alaoui
- Laboratoire “Microorganismes: Génome et Environnement” (LMGE), UMR 6023, Université Clermont Auvergne and CNRS, F-63000, Clermont-Ferrand, France
| | - Ivan Wawrzyniak
- Laboratoire “Microorganismes: Génome et Environnement” (LMGE), UMR 6023, Université Clermont Auvergne and CNRS, F-63000, Clermont-Ferrand, France
| | - Eric Peyretaillade
- Laboratoire “Microorganismes: Génome et Environnement” (LMGE), UMR 6023, Université Clermont Auvergne and CNRS, F-63000, Clermont-Ferrand, France
| |
Collapse
|
8
|
Žárský V, Karnkowska A, Boscaro V, Trznadel M, Whelan TA, Hiltunen-Thorén M, Onut-Brännström I, Abbott CL, Fast NM, Burki F, Keeling PJ. Contrasting outcomes of genome reduction in mikrocytids and microsporidians. BMC Biol 2023; 21:137. [PMID: 37280585 DOI: 10.1186/s12915-023-01635-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/26/2023] [Indexed: 06/08/2023] Open
Abstract
BACKGROUND Intracellular symbionts often undergo genome reduction, losing both coding and non-coding DNA in a process that ultimately produces small, gene-dense genomes with few genes. Among eukaryotes, an extreme example is found in microsporidians, which are anaerobic, obligate intracellular parasites related to fungi that have the smallest nuclear genomes known (except for the relic nucleomorphs of some secondary plastids). Mikrocytids are superficially similar to microsporidians: they are also small, reduced, obligate parasites; however, as they belong to a very different branch of the tree of eukaryotes, the rhizarians, such similarities must have evolved in parallel. Since little genomic data are available from mikrocytids, we assembled a draft genome of the type species, Mikrocytos mackini, and compared the genomic architecture and content of microsporidians and mikrocytids to identify common characteristics of reduction and possible convergent evolution. RESULTS At the coarsest level, the genome of M. mackini does not exhibit signs of extreme genome reduction; at 49.7 Mbp with 14,372 genes, the assembly is much larger and gene-rich than those of microsporidians. However, much of the genomic sequence and most (8075) of the protein-coding genes code for transposons, and may not contribute much of functional relevance to the parasite. Indeed, the energy and carbon metabolism of M. mackini share several similarities with those of microsporidians. Overall, the predicted proteome involved in cellular functions is quite reduced and gene sequences are extremely divergent. Microsporidians and mikrocytids also share highly reduced spliceosomes that have retained a strikingly similar subset of proteins despite having reduced independently. In contrast, the spliceosomal introns in mikrocytids are very different from those of microsporidians in that they are numerous, conserved in sequence, and constrained to an exceptionally narrow size range (all 16 or 17 nucleotides long) at the shortest extreme of known intron lengths. CONCLUSIONS Nuclear genome reduction has taken place many times and has proceeded along different routes in different lineages. Mikrocytids show a mix of similarities and differences with other extreme cases, including uncoupling the actual size of a genome with its functional reduction.
Collapse
Affiliation(s)
- Vojtečh Žárský
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada
| | - Anna Karnkowska
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada
- Institute of Evolutionary Biology, Faculty of Biology, University of Warsaw, 02-089, Warsaw, Poland
| | - Vittorio Boscaro
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada.
| | - Morelia Trznadel
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada
| | - Thomas A Whelan
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada
| | - Markus Hiltunen-Thorén
- Department of Organismal Biology, Uppsala University, Norbyv. 18D, 752 36, Uppsala, Sweden
- Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91, Stockholm, Sweden
| | - Ioana Onut-Brännström
- Department of Organismal Biology, Uppsala University, Norbyv. 18D, 752 36, Uppsala, Sweden
- Department of Ecology and Genetics, Uppsala University, 752 36, Uppsala, Sweden
- Natural History Museum, University of Oslo, 0562, Oslo, Norway
| | - Cathryn L Abbott
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, V9T 6N7, Canada
| | - Naomi M Fast
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada
| | - Fabien Burki
- Department of Organismal Biology, Uppsala University, Norbyv. 18D, 752 36, Uppsala, Sweden
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, V6T 1Z4, Vancouver, 3529-6270 University Boulevard, BC, Canada.
| |
Collapse
|
9
|
Angst P, Ebert D, Fields PD. Population genetic analysis of the microsporidium Ordospora colligata reveals the role of natural selection and phylogeography on its extremely compact and reduced genome. G3 (BETHESDA, MD.) 2023; 13:jkad017. [PMID: 36655395 PMCID: PMC9997559 DOI: 10.1093/g3journal/jkad017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 01/02/2023] [Accepted: 01/11/2023] [Indexed: 01/20/2023]
Abstract
The determinants of variation in a species' genome-wide nucleotide diversity include historical, environmental, and stochastic aspects. This diversity can inform us about the species' past and present evolutionary dynamics. In parasites, the mode of transmission and the interactions with the host might supersede the effects of these aspects in shaping parasite genomic diversity. We used genomic samples from 10 populations of the microsporidian parasite Ordospora colligata to investigate present genomic diversity and how it was shaped by evolutionary processes, specifically, the role of phylogeography, co-phylogeography (with the host), natural selection, and transmission mode. Although very closely related microsporidia cause diseases in humans, O. colligata is specific to the freshwater crustacean Daphnia magna and has one of the smallest known eukaryotic genomes. We found an overlapping phylogeography between O. colligata and its host highlighting the long-term, intimate relationship between them. The observed geographic distribution reflects previous findings that O. colligata exhibits adaptations to colder habitats, which differentiates it from other microsporidian gut parasites of D. magna predominantly found in warmer areas. The co-phylogeography allowed us to calibrate the O. colligata phylogeny and thus estimate its mutation rate. We identified several genetic regions under potential selection. Our whole-genome study provides insights into the evolution of one of the most reduced eukaryotic genomes and shows how different processes shape genomic diversity of an obligate parasite.
Collapse
Affiliation(s)
- Pascal Angst
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| |
Collapse
|
10
|
Smith G, Manzano-Marín A, Reyes-Prieto M, Antunes CSR, Ashworth V, Goselle ON, Jan AAA, Moya A, Latorre A, Perotti MA, Braig HR. Human follicular mites: Ectoparasites becoming symbionts. Mol Biol Evol 2022; 39:msac125. [PMID: 35724423 PMCID: PMC9218549 DOI: 10.1093/molbev/msac125] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 05/23/2022] [Accepted: 05/31/2022] [Indexed: 12/13/2022] Open
Abstract
Most humans carry mites in the hair follicles of their skin for their entire lives. Follicular mites are the only metazoans tha continuously live on humans. We propose that Demodex folliculorum (Acari) represents a transitional stage from a host-injuring obligate parasite to an obligate symbiont. Here, we describe the profound impact of this transition on the genome and physiology of the mite. Genome sequencing revealed that the permanent host association of D. folliculorum led to an extensive genome reduction through relaxed selection and genetic drift, resulting in the smallest number of protein-coding genes yet identified among panarthropods. Confocal microscopy revealed that this gene loss coincided with an extreme reduction in the number of cells. Single uninucleate muscle cells are sufficient to operate each of the three segments that form each walking leg. While it has been assumed that the reduction of the cell number in parasites starts early in development, we identified a greater total number of cells in the last developmental stage (nymph) than in the terminal adult stage, suggesting that reduction starts at the adult or ultimate stage of development. This is the first evolutionary step in an arthropod species adopting a reductive, parasitic or endosymbiotic lifestyle. Somatic nuclei show underreplication at the diploid stage. Novel eye structures or photoreceptors as well as a unique human host melatonin-guided day/night rhythm are proposed for the first time. The loss of DNA repair genes coupled with extreme endogamy might have set this mite species on an evolutionary dead-end trajectory.
Collapse
Affiliation(s)
- Gilbert Smith
- School of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
| | - Alejandro Manzano-Marín
- Centre for Microbiology and Environmental Systems Science (CMESS), University of Vienna, Vienna, Austria
| | - Mariana Reyes-Prieto
- Institute of Integrative Systems Biology (I2Sysbio), Universitat de València and Spanish Research Council (CSIC), València, Spain
- Foundation for the Promotion of Health and Biomedical Research of the Valencian Community (FISABIO), València, Spain
| | | | - Victoria Ashworth
- School of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
| | - Obed Nanjul Goselle
- School of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
| | | | - Andrés Moya
- Institute of Integrative Systems Biology (I2Sysbio), Universitat de València and Spanish Research Council (CSIC), València, Spain
- Foundation for the Promotion of Health and Biomedical Research of the Valencian Community (FISABIO), València, Spain
- Center for Networked Biomedical Research in Epidemiology and Public Health (CIBEResp), Madrid, Spain
| | - Amparo Latorre
- Institute of Integrative Systems Biology (I2Sysbio), Universitat de València and Spanish Research Council (CSIC), València, Spain
- Foundation for the Promotion of Health and Biomedical Research of the Valencian Community (FISABIO), València, Spain
- Center for Networked Biomedical Research in Epidemiology and Public Health (CIBEResp), Madrid, Spain
| | - M Alejandra Perotti
- School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Henk R Braig
- School of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
- Institute and Museum of Natural Sciences, National University of San Juan, San Juan, Argentina
| |
Collapse
|
11
|
Angst P, Ebert D, Fields PD. Demographic history shapes genomic variation in an intracellular parasite with a wide geographic distribution. Mol Ecol 2022; 31:2528-2544. [DOI: 10.1111/mec.16419] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/14/2022] [Accepted: 02/28/2022] [Indexed: 11/27/2022]
Affiliation(s)
- Pascal Angst
- Department of Environmental Sciences, Zoology University of Basel Vesalgasse 1 4051 Basel Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology University of Basel Vesalgasse 1 4051 Basel Switzerland
| | - Peter D. Fields
- Department of Environmental Sciences, Zoology University of Basel Vesalgasse 1 4051 Basel Switzerland
| |
Collapse
|
12
|
van Dijk B, Bertels F, Stolk L, Takeuchi N, Rainey PB. Transposable elements promote the evolution of genome streamlining. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200477. [PMID: 34839699 PMCID: PMC8628081 DOI: 10.1098/rstb.2020.0477] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 08/30/2021] [Indexed: 12/25/2022] Open
Abstract
Eukaryotes and prokaryotes have distinct genome architectures, with marked differences in genome size, the ratio of coding/non-coding DNA, and the abundance of transposable elements (TEs). As TEs replicate independently of their hosts, the proliferation of TEs is thought to have driven genome expansion in eukaryotes. However, prokaryotes also have TEs in intergenic spaces, so why do prokaryotes have small, streamlined genomes? Using an in silico model describing the genomes of single-celled asexual organisms that coevolve with TEs, we show that TEs acquired from the environment by horizontal gene transfer can promote the evolution of genome streamlining. The process depends on local interactions and is underpinned by rock-paper-scissors dynamics in which populations of cells with streamlined genomes beat TEs, which beat non-streamlined genomes, which beat streamlined genomes, in continuous and repeating cycles. Streamlining is maladaptive to individual cells, but improves lineage viability by hindering the proliferation of TEs. Streamlining does not evolve in sexually reproducing populations because recombination partially frees TEs from the deleterious effects they cause. This article is part of the theme issue 'The secret lives of microbial mobile genetic elements'.
Collapse
Affiliation(s)
- Bram van Dijk
- Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Frederic Bertels
- Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Lianne Stolk
- Theoretical Biology, Department of Biology, Utrecht University, The Netherlands
| | - Nobuto Takeuchi
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Paul B. Rainey
- Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany
- Laboratory of Biophysics and Evolution, CBI, ESPCI Paris, Université PSL, CNRS, Paris, France
| |
Collapse
|
13
|
Pradhan RK, Ramakrishna W. Transposons: Unexpected players in cancer. Gene 2022; 808:145975. [PMID: 34592349 DOI: 10.1016/j.gene.2021.145975] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 09/19/2021] [Accepted: 09/24/2021] [Indexed: 12/21/2022]
Abstract
Transposons are repetitive DNA sequences encompassing about half of the human genome. They play a vital role in genome stability maintenance and contribute to genomic diversity and evolution. Their activity is regulated by various mechanisms considering the deleterious effects of these mobile elements. Various genetic risk factors and environmental stress conditions affect the regulatory pathways causing alteration of transposon expression. Our knowledge of the biological role of transposons is limited especially in various types of cancers. Retrotransposons of different types (LTR-retrotransposons, LINEs and SINEs) regulate a plethora of genes that have a role in cell reprogramming, tumor suppression, cell cycle, apoptosis, cell adhesion and migration, and DNA repair. The regulatory mechanisms of transposons, their deregulation and different mechanisms underlying transposon-mediated carcinogenesis in humans focusing on the three most prevalent types, lung, breast and colorectal cancers, were reviewed. The modes of regulation employed include alternative splicing, deletion, insertion, duplication in genes and promoters resulting in upregulation, downregulation or silencing of genes.
Collapse
|
14
|
Jespersen N, Monrroy L, Barandun J. Impact of Genome Reduction in Microsporidia. EXPERIENTIA SUPPLEMENTUM (2012) 2022; 114:1-42. [PMID: 35543997 DOI: 10.1007/978-3-030-93306-7_1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Microsporidia represent an evolutionary outlier in the tree of life and occupy the extreme edge of the eukaryotic domain with some of their biological features. Many of these unicellular fungi-like organisms have reduced their genomic content to potentially the lowest limit. With some of the most compacted eukaryotic genomes, microsporidia are excellent model organisms to study reductive evolution and its functional consequences. While the growing number of sequenced microsporidian genomes have elucidated genome composition and organization, a recent increase in complementary post-genomic studies has started to shed light on the impacts of genome reduction in these unique pathogens. This chapter will discuss the biological framework enabling genome minimization and will use one of the most ancient and essential macromolecular complexes, the ribosome, to illustrate the effects of extreme genome reduction on a structural, molecular, and cellular level. We outline how reductive evolution in microsporidia has shaped DNA organization, the composition and function of the ribosome, and the complexity of the ribosome biogenesis process. Studying compacted mechanisms, processes, or macromolecular machines in microsporidia illuminates their unique lifestyle and provides valuable insights for comparative eukaryotic structural biology.
Collapse
Affiliation(s)
- 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.
| | - Leonardo Monrroy
- 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
| | - 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
|
15
|
Williams BAP, Williams TA, Trew J. Comparative Genomics of Microsporidia. EXPERIENTIA SUPPLEMENTUM (2012) 2022; 114:43-69. [PMID: 35543998 DOI: 10.1007/978-3-030-93306-7_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The microsporidia are a phylum of intracellular parasites that represent the eukaryotic cell in a state of extreme reduction, with genomes and metabolic capabilities embodying eukaryotic cells in arguably their most streamlined state. Over the past 20 years, microsporidian genomics has become a rapidly expanding field starting with sequencing of the genome of Encephalitozoon cuniculi, one of the first ever sequenced eukaryotes, to the current situation where we have access to the data from over 30 genomes across 20+ genera. Reaching back further in evolutionary history, to the point where microsporidia diverged from other eukaryotic lineages, we now also have genomic data for some of the closest known relatives of the microsporidia such as Rozella allomycis, Metchnikovella spp. and Amphiamblys sp. Data for these organisms allow us to better understand the genomic processes that shaped the emergence of the microsporidia as a group. These intensive genomic efforts have revealed some of the processes that have shaped microsporidian cells and genomes including patterns of genome expansions and contractions through gene gain and loss, whole genome duplication, differential patterns of invasion and purging of transposable elements. All these processes have been shown to occur across short and longer time scales to give rise to a phylum of parasites with dynamic genomes with a diversity of sizes and organisations.
Collapse
Affiliation(s)
| | - Tom A Williams
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Jahcub Trew
- School of Biosciences, University of Exeter, Exeter, UK
| |
Collapse
|
16
|
Lopes ALK, Kriegová E, Lukeš J, Krieger MA, Ludwig A. Distribution of Merlin in eukaryotes and first report of DNA transposons in kinetoplastid protists. PLoS One 2021; 16:e0251133. [PMID: 33956864 PMCID: PMC8101967 DOI: 10.1371/journal.pone.0251133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 04/21/2021] [Indexed: 11/19/2022] Open
Abstract
DNA transposons are defined as repeated DNA sequences that can move within the host genome through the action of transposases. The transposon superfamily Merlin was originally found mainly in animal genomes. Here, we describe a global distribution of the Merlin in animals, fungi, plants and protists, reporting for the first time their presence in Rhodophyceae, Metamonada, Discoba and Alveolata. We identified a great variety of potentially active Merlin families, some containing highly imperfect terminal inverted repeats and internal tandem repeats. Merlin-related sequences with no evidence of mobilization capacity were also observed and may be products of domestication. The evolutionary trees support that Merlin is likely an ancient superfamily, with early events of diversification and secondary losses, although repeated re-invasions probably occurred in some groups, which would explain its diversity and discontinuous distribution. We cannot rule out the possibility that the Merlin superfamily is the product of multiple horizontal transfers of related prokaryotic insertion sequences. Moreover, this is the first account of a DNA transposon in kinetoplastid flagellates, with conserved Merlin transposase identified in Bodo saltans and Perkinsela sp., whereas it is absent in trypanosomatids. Based on the level of conservation of the transposase and overlaps of putative open reading frames with Merlin, we propose that in protists it may serve as a raw material for gene emergence.
Collapse
Affiliation(s)
- Ana Luisa Kalb Lopes
- Pós-Graduação em Biologia Celular e Molecular, Universidade Federal do Paraná, Curitiba, PR, Brazil
- Laboratório de Ciências e Tecnologias Aplicadas em Saúde (LaCTAS), Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, PR, Brazil
- Instituto de Biologia Molecular do Paraná, Curitiba, PR, Brazil
| | - Eva Kriegová
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Marco Aurélio Krieger
- Pós-Graduação em Biologia Celular e Molecular, Universidade Federal do Paraná, Curitiba, PR, Brazil
- Laboratório de Ciências e Tecnologias Aplicadas em Saúde (LaCTAS), Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, PR, Brazil
| | - Adriana Ludwig
- Laboratório de Ciências e Tecnologias Aplicadas em Saúde (LaCTAS), Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, PR, Brazil
- * E-mail:
| |
Collapse
|