1
|
Keeling PJ. Horizontal gene transfer in eukaryotes: aligning theory with data. Nat Rev Genet 2024; 25:416-430. [PMID: 38263430 DOI: 10.1038/s41576-023-00688-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2023] [Indexed: 01/25/2024]
Abstract
Horizontal gene transfer (HGT), or lateral gene transfer, is the non-sexual movement of genetic information between genomes. It has played a pronounced part in bacterial and archaeal evolution, but its role in eukaryotes is less clear. Behaviours unique to eukaryotic cells - phagocytosis and endosymbiosis - have been proposed to increase the frequency of HGT, but nuclear genomes encode fewer HGTs than bacteria and archaea. Here, I review the existing theory in the context of the growing body of data on HGT in eukaryotes, which suggests that any increased chance of acquiring new genes through phagocytosis and endosymbiosis is offset by a reduced need for these genes in eukaryotes, because selection in most eukaryotes operates on variation not readily generated by HGT.
Collapse
Affiliation(s)
- Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
2
|
D'Ambrosio HK, Keeler AM, Derbyshire ER. Examination of Secondary Metabolite Biosynthesis in Apicomplexa. Chembiochem 2023; 24:e202300263. [PMID: 37171468 DOI: 10.1002/cbic.202300263] [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: 04/01/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/13/2023]
Abstract
Natural product discovery has traditionally relied on the isolation of small molecules from producing species, but genome-sequencing technology and advances in molecular biology techniques have expanded efforts to a wider array of organisms. Protists represent an underexplored kingdom for specialized metabolite searches despite bioinformatic analysis that suggests they harbor distinct biologically active small molecules. Specifically, pathogenic apicomplexan parasites, responsible for billions of global infections, have been found to possess multiple biosynthetic gene clusters, which hints at their capacity to produce polyketide metabolites. Biochemical studies have revealed unique features of apicomplexan polyketide synthases, but to date, the identity and function of the polyketides synthesized by these megaenzymes remains unknown. Herein, we discuss the potential for specialized metabolite production in protists and the possible evolution of polyketide biosynthetic gene clusters in apicomplexan parasites. We then focus on a polyketide synthase from the apicomplexan Toxoplasma gondii to discuss the unique domain architecture and properties of these proteins when compared to previously characterized systems, and further speculate on the possible functions for polyketides in these pathogenic parasites.
Collapse
Affiliation(s)
- Hannah K D'Ambrosio
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Aaron M Keeler
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Emily R Derbyshire
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, NC 27710, USA
| |
Collapse
|
3
|
Sato N. Are Cyanobacteria an Ancestor of Chloroplasts or Just One of the Gene Donors for Plants and Algae? Genes (Basel) 2021; 12:genes12060823. [PMID: 34071987 PMCID: PMC8227023 DOI: 10.3390/genes12060823] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/08/2021] [Accepted: 05/25/2021] [Indexed: 12/04/2022] Open
Abstract
Chloroplasts of plants and algae are currently believed to originate from a cyanobacterial endosymbiont, mainly based on the shared proteins involved in the oxygenic photosynthesis and gene expression system. The phylogenetic relationship between the chloroplast and cyanobacterial genomes was important evidence for the notion that chloroplasts originated from cyanobacterial endosymbiosis. However, studies in the post-genomic era revealed that various substances (glycolipids, peptidoglycan, etc.) shared by cyanobacteria and chloroplasts are synthesized by different pathways or phylogenetically unrelated enzymes. Membranes and genomes are essential components of a cell (or an organelle), but the origins of these turned out to be different. Besides, phylogenetic trees of chloroplast-encoded genes suggest an alternative possibility that chloroplast genes could be acquired from at least three different lineages of cyanobacteria. We have to seriously examine that the chloroplast genome might be chimeric due to various independent gene flows from cyanobacteria. Chloroplast formation could be more complex than a single event of cyanobacterial endosymbiosis. I present the “host-directed chloroplast formation” hypothesis, in which the eukaryotic host cell that had acquired glycolipid synthesis genes as an adaptation to phosphate limitation facilitated chloroplast formation by providing glycolipid-based membranes (pre-adaptation). The origins of the membranes and the genome could be different, and the origin of the genome could be complex.
Collapse
Affiliation(s)
- Naoki Sato
- Graduate School of Arts and Sciences, University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| |
Collapse
|
4
|
Is mitochondrial DNA profiling predictive for athletic performance? Mitochondrion 2019; 47:125-138. [PMID: 31228565 DOI: 10.1016/j.mito.2019.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 06/03/2019] [Accepted: 06/17/2019] [Indexed: 11/20/2022]
Abstract
Mitochondrial DNA encodes some proteins of the oxidative phosphorylation enzymatic complex, playing an important role in aerobic ATP production; therefore, it can contribute to the ability to respond to endurance exercise training. The accumulation of mitochondrial mutations and the migratory processes of populations have given a great contribution to the development of haplogroups with a different distribution in the world. Several studies have shown the important role of gene polymorphisms in aerobic performance. In this review, some mitochondrial haplogroups and multiple rare alleles were taken into consideration and could be linked to the athlete's physical performance of different ethnic groups.
Collapse
|
5
|
Shapiro JA. No genome is an island: toward a 21st century agenda for evolution. Ann N Y Acad Sci 2019; 1447:21-52. [DOI: 10.1111/nyas.14044] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/17/2019] [Accepted: 02/02/2019] [Indexed: 12/21/2022]
Affiliation(s)
- James A. Shapiro
- Department of Biochemistry and Molecular BiologyUniversity of Chicago Chicago Illinois
| |
Collapse
|
6
|
Oborník M. In the beginning was the word: How terminology drives our understanding of endosymbiotic organelles. MICROBIAL CELL (GRAZ, AUSTRIA) 2019; 6:134-141. [PMID: 30740458 PMCID: PMC6364260 DOI: 10.15698/mic2019.02.669] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 11/14/2018] [Accepted: 11/29/2018] [Indexed: 11/24/2022]
Abstract
The names we give objects of research, to some extent, predispose our ways of thinking about them. Misclassifications of Oomycota, Microsporidia, Myxosporidia, and Helicosporidia have obviously affected not only their formal taxonomic names, but also the methods and approaches with which they have been investigated. Therefore, it is important to name biological entities with accurate terms in order to avoid discrepancies in researching them. The endosymbiotic origin of mitochondria and plastids is now the most accepted scenario for their evolution. Since it is apparent that there is no natural definitive border between bacteria and semiautonomous organelles, I propose that mitochondria and plastids should be called bacteria and classified accordingly, in the bacterial classification system. I discuss some consequences of this approach, including: i) the resulting "changes" in the abundances of bacteria, ii) the definitions of terms like microbiome or multicellularity, and iii) the concept of endosymbiotic domestication.
Collapse
Affiliation(s)
- Miroslav Oborník
- Biology Centre CAS, Institute of Parasitology, České Budějovice, Czech Republic
- University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| |
Collapse
|
7
|
Tilquin A, Christie JR, Kokko H. Mitochondrial complementation: a possible neglected factor behind early eukaryotic sex. J Evol Biol 2018; 31:1152-1164. [DOI: 10.1111/jeb.13293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/17/2018] [Accepted: 05/22/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Anaïs Tilquin
- Department of Evolutionary Biology and Environmental Studies; University of Zurich; Zurich Switzerland
- Finnish Centre of Excellence in Biological Interactions; Jyväskylä Finland
| | - Joshua R. Christie
- Department of Evolutionary Biology and Environmental Studies; University of Zurich; Zurich Switzerland
- Finnish Centre of Excellence in Biological Interactions; Jyväskylä Finland
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies; University of Zurich; Zurich Switzerland
- Finnish Centre of Excellence in Biological Interactions; Jyväskylä Finland
| |
Collapse
|
8
|
Eme L, Spang A, Lombard J, Stairs CW, Ettema TJG. Archaea and the origin of eukaryotes. Nat Rev Microbiol 2017; 15:711-723. [DOI: 10.1038/nrmicro.2017.133] [Citation(s) in RCA: 279] [Impact Index Per Article: 39.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
9
|
Ganley JG, Toro-Moreno M, Derbyshire ER. Exploring the Untapped Biosynthetic Potential of Apicomplexan Parasites. Biochemistry 2017; 57:365-375. [DOI: 10.1021/acs.biochem.7b00877] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jack G. Ganley
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
| | - Maria Toro-Moreno
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
| | - Emily R. Derbyshire
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
- Department
of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, North Carolina 27710, United States
| |
Collapse
|
10
|
Abstract
Endosymbiosis is an idea that provided a remarkable amount of explanatory power about the origins of eukaryotic organelles. But it also promoted a number of assumptions that have also been influential, but are less well-examined. Here we look at two of these to see whether or not they fit current evidence. The assumption we first address is that endosymbiotic relationships such as nutritional symbioses and eukaryotic organelles are mutualisms. We argue instead that they are more one-sided associations that can be regarded as context-dependent power struggles like any other ecological interaction. The second assumption is that during endosymbiotic interactions (such as the origin of organelles), the host genomes will acquire a great many genes from endosymbionts that assume functions in host systems (as opposed to the well-documented genes whose products are simply targeted back to the endosymbiont or organelle). The idea that these genes exist in large numbers has been influential in a number of hypotheses about organelle evolution and distribution, but in the most carefully-examined systems no such mass migration of genes is evident. Overall, we argue that both the nature and impact of endosymbiosis need to be constantly re-evaluated to fully understand what roles it really plays in both cell biology and evolution.
Collapse
|
11
|
López-García P, Eme L, Moreira D. Symbiosis in eukaryotic evolution. J Theor Biol 2017; 434:20-33. [PMID: 28254477 DOI: 10.1016/j.jtbi.2017.02.031] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/19/2017] [Accepted: 02/25/2017] [Indexed: 01/27/2023]
Abstract
Fifty years ago, Lynn Margulis, inspiring in early twentieth-century ideas that put forward a symbiotic origin for some eukaryotic organelles, proposed a unified theory for the origin of the eukaryotic cell based on symbiosis as evolutionary mechanism. Margulis was profoundly aware of the importance of symbiosis in the natural microbial world and anticipated the evolutionary significance that integrated cooperative interactions might have as mechanism to increase cellular complexity. Today, we have started fully appreciating the vast extent of microbial diversity and the importance of syntrophic metabolic cooperation in natural ecosystems, especially in sediments and microbial mats. Also, not only the symbiogenetic origin of mitochondria and chloroplasts has been clearly demonstrated, but improvement in phylogenomic methods combined with recent discoveries of archaeal lineages more closely related to eukaryotes further support the symbiogenetic origin of the eukaryotic cell. Margulis left us in legacy the idea of 'eukaryogenesis by symbiogenesis'. Although this has been largely verified, when, where, and specifically how eukaryotic cells evolved are yet unclear. Here, we shortly review current knowledge about symbiotic interactions in the microbial world and their evolutionary impact, the status of eukaryogenetic models and the current challenges and perspectives ahead to reconstruct the evolutionary path to eukaryotes.
Collapse
Affiliation(s)
- Purificación López-García
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, Université Paris-Saclay, AgroParisTech, 91400 Orsay, France.
| | - Laura Eme
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada NS B3H 4R2
| | - David Moreira
- Ecologie Systématique Evolution, CNRS, Université Paris-Sud, Université Paris-Saclay, AgroParisTech, 91400 Orsay, France
| |
Collapse
|
12
|
Kurland CG, Harish A. The phylogenomics of protein structures: The backstory. Biochimie 2015; 119:284-302. [DOI: 10.1016/j.biochi.2015.07.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 07/28/2015] [Indexed: 12/11/2022]
|
13
|
Open Questions on the Origin of Eukaryotes. Trends Ecol Evol 2015; 30:697-708. [PMID: 26455774 DOI: 10.1016/j.tree.2015.09.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/03/2015] [Accepted: 09/04/2015] [Indexed: 12/21/2022]
Abstract
Despite recent progress, the origin of the eukaryotic cell remains enigmatic. It is now known that the last eukaryotic common ancestor was complex and that endosymbiosis played a crucial role in eukaryogenesis at least via the acquisition of the alphaproteobacterial ancestor of mitochondria. However, the nature of the mitochondrial host is controversial, although the recent discovery of an archaeal lineage phylogenetically close to eukaryotes reinforces models proposing archaea-derived hosts. We argue that, in addition to improved phylogenomic analyses with more comprehensive taxon sampling to pinpoint the closest prokaryotic relatives of eukaryotes, determining plausible mechanisms and selective forces at the origin of key eukaryotic features, such as the nucleus or the bacterial-like eukaryotic membrane system, is essential to constrain existing models.
Collapse
|
14
|
|
15
|
Abstract
Historically, conceptualizations of symbiosis and endosymbiosis have been pitted against Darwinian or neo-Darwinian evolutionary theory. In more recent times, Lynn Margulis has argued vigorously along these lines. However, there are only shallow grounds for finding Darwinian concepts or population genetic theory incompatible with endosymbiosis. But is population genetics sufficiently explanatory of endosymbiosis and its role in evolution? Population genetics "follows" genes, is replication-centric, and is concerned with vertically consistent genetic lineages. It may also have explanatory limitations with regard to macroevolution. Even so, asking whether population genetics explains endosymbiosis may have the question the wrong way around. We should instead be asking how explanatory of evolution endosymbiosis is, and exactly which features of evolution it might be explaining. This paper will discuss how metabolic innovations associated with endosymbioses can drive evolution and thus provide an explanatory account of important episodes in the history of life. Metabolic explanations are both proximate and ultimate, in the same way genetic explanations are. Endosymbioses, therefore, point evolutionary biology toward an important dimension of evolutionary explanation.
Collapse
|
16
|
Abstract
Animals evolved in seas teeming with bacteria, yet the influences of bacteria on animal origins are poorly understood. Comparisons among modern animals and their closest living relatives, the choanoflagellates, suggest that the first animals used flagellated collar cells to capture bacterial prey. The cell biology of prey capture, such as cell adhesion between predator and prey, involves mechanisms that may have been co-opted to mediate intercellular interactions during the evolution of animal multicellularity. Moreover, a history of bacterivory may have influenced the evolution of animal genomes by driving the evolution of genetic pathways for immunity and facilitating lateral gene transfer. Understanding the interactions between bacteria and the progenitors of animals may help to explain the myriad ways in which bacteria shape the biology of modern animals, including ourselves.
Collapse
Affiliation(s)
- Rosanna A Alegado
- Department of Oceanography, Center for Microbial Oceanography: Research and Education, Sea Grant College, University of Hawai'i Mānoa, Honolulu, Hawaii 96822
| | - Nicole King
- Howard Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, California 94720
| |
Collapse
|
17
|
Gray MW. The pre-endosymbiont hypothesis: a new perspective on the origin and evolution of mitochondria. Cold Spring Harb Perspect Biol 2014; 6:6/3/a016097. [PMID: 24591518 DOI: 10.1101/cshperspect.a016097] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Mitochondrial DNA (mtDNA) is unquestionably the remnant of an α-proteobacterial genome, yet only ~10%-20% of mitochondrial proteins are demonstrably α-proteobacterial in origin (the "α-proteobacterial component," or APC). The evolutionary ancestry of the non-α-proteobacterial component (NPC) is obscure and not adequately accounted for in current models of mitochondrial origin. I propose that in the host cell that accommodated an α-proteobacterial endosymbiont, much of the NPC was already present, in the form of a membrane-bound metabolic organelle (the premitochondrion) that compartmentalized many of the non-energy-generating functions of the contemporary mitochondrion. I suggest that this organelle also possessed a protein import system and various ion and small-molecule transporters. In such a scenario, an α-proteobacterial endosymbiont could have been converted relatively directly and rapidly into an energy-generating organelle that incorporated the extant metabolic functions of the premitochondrion. This model (the "pre-endosymbiont hypothesis") effectively represents a synthesis of previous, contending mitochondrial origin hypotheses, with the bulk of the mitochondrial proteome (much of the NPC) having an endogenous origin and the minority component (the APC) having a xenogenous origin.
Collapse
Affiliation(s)
- Michael W Gray
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3M 4R2, Canada
| |
Collapse
|