51
|
Ball SG, Colleoni C, Kadouche D, Ducatez M, Arias MC, Tirtiaux C. Toward an understanding of the function of Chlamydiales in plastid endosymbiosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:495-504. [PMID: 25687892 DOI: 10.1016/j.bbabio.2015.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 02/03/2015] [Accepted: 02/07/2015] [Indexed: 12/29/2022]
Abstract
Plastid endosymbiosis defines a process through which a fully evolved cyanobacterial ancestor has transmitted to a eukaryotic phagotroph the hundreds of genes required to perform oxygenic photosynthesis, together with the membrane structures, and cellular compartment associated with this process. In this review, we will summarize the evidence pointing to an active role of Chlamydiales in metabolic integration of free living cyanobacteria, within the cytosol of the last common plant ancestor.
Collapse
Affiliation(s)
- Steven G Ball
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France.
| | - Christophe Colleoni
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France
| | - Derifa Kadouche
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France
| | - Mathieu Ducatez
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France
| | - Maria-Cecilia Arias
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France
| | - Catherine Tirtiaux
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d'Ascq cedex, France
| |
Collapse
|
52
|
Bobik K, Burch-Smith TM. Chloroplast signaling within, between and beyond cells. FRONTIERS IN PLANT SCIENCE 2015; 6:781. [PMID: 26500659 PMCID: PMC4593955 DOI: 10.3389/fpls.2015.00781] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/10/2015] [Indexed: 05/18/2023]
Abstract
The most conspicuous function of plastids is the oxygenic photosynthesis of chloroplasts, yet plastids are super-factories that produce a plethora of compounds that are indispensable for proper plant physiology and development. Given their origins as free-living prokaryotes, it is not surprising that plastids possess their own genomes whose expression is essential to plastid function. This semi-autonomous character of plastids requires the existence of sophisticated regulatory mechanisms that provide reliable communication between them and other cellular compartments. Such intracellular signaling is necessary for coordinating whole-cell responses to constantly varying environmental cues and cellular metabolic needs. This is achieved by plastids acting as receivers and transmitters of specific signals that coordinate expression of the nuclear and plastid genomes according to particular needs. In this review we will consider the so-called retrograde signaling occurring between plastids and nuclei, and between plastids and other organelles. Another important role of the plastid we will discuss is the involvement of plastid signaling in biotic and abiotic stress that, in addition to influencing retrograde signaling, has direct effects on several cellular compartments including the cell wall. We will also review recent evidence pointing to an intriguing function of chloroplasts in regulating intercellular symplasmic transport. Finally, we consider an intriguing yet less widely known aspect of plant biology, chloroplast signaling from the perspective of the entire plant. Thus, accumulating evidence highlights that chloroplasts, with their complex signaling pathways, provide a mechanism for exquisite regulation of plant development, metabolism and responses to the environment. As chloroplast processes are targeted for engineering for improved productivity the effect of such modifications on chloroplast signaling will have to be carefully considered in order to avoid unintended consequences on plant growth and development.
Collapse
Affiliation(s)
| | - Tessa M. Burch-Smith
- *Correspondence: Tessa M. Burch-Smith, Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, 1414 Cumberland Avenue, M407 Walters Life Science, Knoxville, TN 37932, USA,
| |
Collapse
|
53
|
Knie N, Polsakiewicz M, Knoop V. Horizontal gene transfer of chlamydial-like tRNA genes into early vascular plant mitochondria. Mol Biol Evol 2014; 32:629-34. [PMID: 25415968 DOI: 10.1093/molbev/msu324] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mitochondrial genomes of lycophytes are surprisingly diverse, including strikingly different transfer RNA (tRNA) gene complements: No mitochondrial tRNA genes are present in the spikemoss Selaginella moellendorffii, whereas 26 tRNAs are encoded in the chondrome of the clubmoss Huperzia squarrosa. Reinvestigating the latter we found that trnL(gag) and trnS(gga) had never before been identified in any other land plant mitochondrial DNA. Sensitive sequence comparisons showed these two tRNAs as well as trnN(guu) and trnS(gcu) to be very similar to their respective counterparts in chlamydial bacteria. We identified homologs of these chlamydial-type tRNAs also in other lycophyte, fern, and gymnosperm DNAs, suggesting horizontal gene transfer (HGT) into mitochondria in the early vascular plant stem lineages. These findings extend plant mitochondrial HGT to affect individual tRNA genes, to include bacterial donors, and suggest that Chlamydiae on top of their recently proposed key role in primary chloroplast establishment may also have participated in early tracheophyte genome evolution.
Collapse
Affiliation(s)
- Nils Knie
- Abteilung Molekulare Evolution, Institut für Zelluläre und Molekulare Botanik, Universität Bonn, Bonn, Germany
| | - Monika Polsakiewicz
- Abteilung Molekulare Evolution, Institut für Zelluläre und Molekulare Botanik, Universität Bonn, Bonn, Germany
| | - Volker Knoop
- Abteilung Molekulare Evolution, Institut für Zelluläre und Molekulare Botanik, Universität Bonn, Bonn, Germany
| |
Collapse
|
54
|
Rockwell NC, Lagarias JC, Bhattacharya D. Primary endosymbiosis and the evolution of light and oxygen sensing in photosynthetic eukaryotes. Front Ecol Evol 2014; 2. [PMID: 25729749 DOI: 10.3389/fevo.2014.00066] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The origin of the photosynthetic organelle in eukaryotes, the plastid, changed forever the evolutionary trajectory of life on our planet. Plastids are highly specialized compartments derived from a putative single cyanobacterial primary endosymbiosis that occurred in the common ancestor of the supergroup Archaeplastida that comprises the Viridiplantae (green algae and plants), red algae, and glaucophyte algae. These lineages include critical primary producers of freshwater and terrestrial ecosystems, progenitors of which provided plastids through secondary endosymbiosis to other algae such as diatoms and dinoflagellates that are critical to marine ecosystems. Despite its broad importance and the success of algal and plant lineages, the phagotrophic origin of the plastid imposed an interesting challenge on the predatory eukaryotic ancestor of the Archaeplastida. By engulfing an oxygenic photosynthetic cell, the host lineage imposed an oxidative stress upon itself in the presence of light. Adaptations to meet this challenge were thus likely to have occurred early on during the transition from a predatory phagotroph to an obligate phototroph (or mixotroph). Modern algae have recently been shown to employ linear tetrapyrroles (bilins) to respond to oxidative stress under high light. Here we explore the early events in plastid evolution and the possible ancient roles of bilins in responding to light and oxygen.
Collapse
Affiliation(s)
- Nathan C Rockwell
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616
| | - J Clark Lagarias
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616
| | - Debashish Bhattacharya
- Department of Ecology, Evolution, and Natural Resources; Institute of Marine and Coastal Science, Rutgers University, New Brunswick, NJ 08903
| |
Collapse
|
55
|
Moreira D, Deschamps P. What was the real contribution of endosymbionts to the eukaryotic nucleus? Insights from photosynthetic eukaryotes. Cold Spring Harb Perspect Biol 2014; 6:a016014. [PMID: 24984774 DOI: 10.1101/cshperspect.a016014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Eukaryotic genomes are composed of genes of different evolutionary origins. This is especially true in the case of photosynthetic eukaryotes, which, in addition to typical eukaryotic genes and genes of mitochondrial origin, also contain genes coming from the primary plastids and, in the case of secondary photosynthetic eukaryotes, many genes provided by the nuclei of red or green algal endosymbionts. Phylogenomic analyses have been applied to detect those genes and, in some cases, have led to proposing the existence of cryptic, no longer visible endosymbionts. However, detecting them is a very difficult task because, most often, those genes were acquired a long time ago and their phylogenetic signal has been heavily erased. We revisit here two examples, the putative cryptic endosymbiosis of green algae in diatoms and chromerids and of Chlamydiae in the first photosynthetic eukaryotes. We show that the evidence sustaining them has been largely overestimated, and we insist on the necessity of careful, accurate phylogenetic analyses to obtain reliable results.
Collapse
Affiliation(s)
- David Moreira
- Unité d'Ecologie, Systématique et Evolution, UMR CNRS 8079, Université Paris-Sud, 91405 Orsay Cedex, France
| | - Philippe Deschamps
- Unité d'Ecologie, Systématique et Evolution, UMR CNRS 8079, Université Paris-Sud, 91405 Orsay Cedex, France
| |
Collapse
|
56
|
Nakabachi A, Ishida K, Hongoh Y, Ohkuma M, Miyagishima SY. Aphid gene of bacterial origin encodes a protein transported to an obligate endosymbiont. Curr Biol 2014; 24:R640-R641. [DOI: 10.1016/j.cub.2014.06.038] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
57
|
Abstract
In this review, we consider a selection of recent advances in chloroplast biology. These include new findings concerning chloroplast evolution, such as the identification of Chlamydiae as a third partner in primary endosymbiosis, a second instance of primary endosymbiosis represented by the chromatophores found in amoebae of the genus Paulinella, and a new explanation for the longevity of captured chloroplasts (kleptoplasts) in sacoglossan sea slugs. The controversy surrounding the three-dimensional structure of grana, its recent resolution by tomographic analyses, and the role of the CURVATURE THYLAKOID1 (CURT1) proteins in supporting grana formation are also discussed. We also present an updated inventory of photosynthetic proteins and the factors involved in the assembly of thylakoid multiprotein complexes, and evaluate findings that reveal that cyclic electron flow involves NADPH dehydrogenase (NDH)- and PGRL1/PGR5-dependent pathways, both of which receive electrons from ferredoxin. Other topics covered in this review include new protein components of nucleoids, an updated inventory of the chloroplast proteome, new enzymes in chlorophyll biosynthesis and new candidate messengers in retrograde signaling. Finally, we discuss the first successful synthetic biology approaches that resulted in chloroplasts in which electrons from the photosynthetic light reactions are fed to enzymes derived from secondary metabolism.
Collapse
Affiliation(s)
- Poul Erik Jensen
- Copenhagen Plant Science Center (CPSC), Department of Plant and Environmental Sciences, University of CopenhagenThorvaldsensvej 40, DK-1871 Frederiksberg CDenmark
| | - Dario Leister
- Copenhagen Plant Science Center (CPSC), Department of Plant and Environmental Sciences, University of CopenhagenThorvaldsensvej 40, DK-1871 Frederiksberg CDenmark
- Plant Molecular Biology, Department of Biology I, Ludwig-Maximilians-University MunichGroßhaderner Str. 2, D-82152 Planegg-MartinsriedGermany
| |
Collapse
|
58
|
Nougué O, Corbi J, Ball SG, Manicacci D, Tenaillon MI. Molecular evolution accompanying functional divergence of duplicated genes along the plant starch biosynthesis pathway. BMC Evol Biol 2014; 14:103. [PMID: 24884572 PMCID: PMC4041918 DOI: 10.1186/1471-2148-14-103] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 05/02/2014] [Indexed: 12/15/2022] Open
Abstract
Background Starch is the main source of carbon storage in the Archaeplastida. The starch biosynthesis pathway (sbp) emerged from cytosolic glycogen metabolism shortly after plastid endosymbiosis and was redirected to the plastid stroma during the green lineage divergence. The SBP is a complex network of genes, most of which are members of large multigene families. While some gene duplications occurred in the Archaeplastida ancestor, most were generated during the sbp redirection process, and the remaining few paralogs were generated through compartmentalization or tissue specialization during the evolution of the land plants. In the present study, we tested models of duplicated gene evolution in order to understand the evolutionary forces that have led to the development of SBP in angiosperms. We combined phylogenetic analyses and tests on the rates of evolution along branches emerging from major duplication events in six gene families encoding sbp enzymes. Results We found evidence of positive selection along branches following cytosolic or plastidial specialization in two starch phosphorylases and identified numerous residues that exhibited changes in volume, polarity or charge. Starch synthases, branching and debranching enzymes functional specializations were also accompanied by accelerated evolution. However, none of the sites targeted by selection corresponded to known functional domains, catalytic or regulatory. Interestingly, among the 13 duplications tested, 7 exhibited evidence of positive selection in both branches emerging from the duplication, 2 in only one branch, and 4 in none of the branches. Conclusions The majority of duplications were followed by accelerated evolution targeting specific residues along both branches. This pattern was consistent with the optimization of the two sub-functions originally fulfilled by the ancestral gene before duplication. Our results thereby provide strong support to the so-called “Escape from Adaptive Conflict” (EAC) model. Because none of the residues targeted by selection occurred in characterized functional domains, we propose that enzyme specialization has occurred through subtle changes in affinity, activity or interaction with other enzymes in complex formation, while the basic function defined by the catalytic domain has been maintained.
Collapse
Affiliation(s)
| | | | | | - Domenica Manicacci
- University Paris-Sud, UMR 0320/UMR 8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France.
| | | |
Collapse
|
59
|
McFadden GI. Origin and evolution of plastids and photosynthesis in eukaryotes. Cold Spring Harb Perspect Biol 2014; 6:a016105. [PMID: 24691960 DOI: 10.1101/cshperspect.a016105] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Recent progress in understanding the origins of plastids from endosymbiotic cyanobacteria is reviewed. Establishing when during geological time the endosymbiosis occurred remains elusive, but progress has been made in defining the cyanobacterial lineage most closely related to plastids, and some mechanistic insight into the possible existence of cryptic endosymbioses perhaps involving Chlamydia-like infections of the host have also been presented. The phylogenetic affinities of the host remain obscure. The existence of a second lineage of primary plastids in euglyphid amoebae has now been confirmed, but the quasipermanent acquisition of plastids by animals has been shown to be more ephemeral than initially suspected. A new understanding of how plastids have been integrated into their hosts by transfer of photosynthate, by endosymbiotic gene transfer and repatriation of gene products back to the endosymbiont, and by regulation of endosymbiont division is presented in context.
Collapse
|
60
|
Sloan DB, Nakabachi A, Richards S, Qu J, Murali SC, Gibbs RA, Moran NA. Parallel histories of horizontal gene transfer facilitated extreme reduction of endosymbiont genomes in sap-feeding insects. Mol Biol Evol 2014; 31:857-71. [PMID: 24398322 DOI: 10.1093/molbev/msu004] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Bacteria confined to intracellular environments experience extensive genome reduction. In extreme cases, insect endosymbionts have evolved genomes that are so gene-poor that they blur the distinction between bacteria and endosymbiotically derived organelles such as mitochondria and plastids. To understand the host's role in this extreme gene loss, we analyzed gene content and expression in the nuclear genome of the psyllid Pachypsylla venusta, a sap-feeding insect that harbors an ancient endosymbiont (Carsonella) with one of the most reduced bacterial genomes ever identified. Carsonella retains many genes required for synthesis of essential amino acids that are scarce in plant sap, but most of these biosynthetic pathways have been disrupted by gene loss. Host genes that are upregulated in psyllid cells housing Carsonella appear to compensate for endosymbiont gene losses, resulting in highly integrated metabolic pathways that mirror those observed in other sap-feeding insects. The host contribution to these pathways is mediated by a combination of native eukaryotic genes and bacterial genes that were horizontally transferred from multiple donor lineages early in the evolution of psyllids, including one gene that appears to have been directly acquired from Carsonella. By comparing the psyllid genome to a recent analysis of mealybugs, we found that a remarkably similar set of functional pathways have been shaped by independent transfers of bacterial genes to the two hosts. These results show that horizontal gene transfer is an important and recurring mechanism driving coevolution between insects and their bacterial endosymbionts and highlight interesting similarities and contrasts with the evolutionary history of mitochondria and plastids.
Collapse
|
61
|
Cenci U, Nitschke F, Steup M, Minassian BA, Colleoni C, Ball SG. Transition from glycogen to starch metabolism in Archaeplastida. TRENDS IN PLANT SCIENCE 2014; 19:18-28. [PMID: 24035236 DOI: 10.1016/j.tplants.2013.08.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/08/2013] [Accepted: 08/09/2013] [Indexed: 05/18/2023]
Abstract
In this opinion article we propose a scenario detailing how two crucial components have evolved simultaneously to ensure the transition of glycogen to starch in the cytosol of the Archaeplastida last common ancestor: (i) the recruitment of an enzyme from intracellular Chlamydiae pathogens to facilitate crystallization of α-glucan chains; and (ii) the evolution of novel types of polysaccharide (de)phosphorylating enzymes from preexisting glycogen (de)phosphorylation host pathways to allow the turnover of such crystals. We speculate that the transition to starch benefitted Archaeplastida in three ways: more carbon could be packed into osmotically inert material; the host could resume control of carbon assimilation from the chlamydial pathogen that triggered plastid endosymbiosis; and cyanobacterial photosynthate export could be integrated in the emerging Archaeplastida.
Collapse
Affiliation(s)
- Ugo Cenci
- Laboratoire de Chimie Biologique, Université des Sciences et Technologies de Lille, CNRS, UMR8576, Cité Scientifique, 59655 Villeneuve d'Ascq, France
| | - Felix Nitschke
- Institute of Biochemistry and Biology and Plant Physiology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
| | - Martin Steup
- Institute of Biochemistry and Biology and Plant Physiology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
| | - Berge A Minassian
- Division of Neurology, Department of Pediatrics, The Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada; Institute of Medical Sciences, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Christophe Colleoni
- Laboratoire de Chimie Biologique, Université des Sciences et Technologies de Lille, CNRS, UMR8576, Cité Scientifique, 59655 Villeneuve d'Ascq, France
| | - Steven G Ball
- Laboratoire de Chimie Biologique, Université des Sciences et Technologies de Lille, CNRS, UMR8576, Cité Scientifique, 59655 Villeneuve d'Ascq, France.
| |
Collapse
|
62
|
Subtil A, Collingro A, Horn M. Tracing the primordial Chlamydiae: extinct parasites of plants? TRENDS IN PLANT SCIENCE 2014; 19:36-43. [PMID: 24210739 DOI: 10.1016/j.tplants.2013.10.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 10/09/2013] [Accepted: 10/15/2013] [Indexed: 06/02/2023]
Abstract
Chlamydiae are obligate intracellular bacteria found as symbionts and pathogens in a wide range of eukaryotes, including protists, invertebrates, and vertebrates. It was recently proposed that an ancient chlamydial symbiont facilitated the establishment of primary plastids in a tripartite symbiosis with cyanobacteria and early eukaryotes. In this review, we summarize recent advances in understanding of the lifestyle and the evolutionary history of extant Chlamydiae. We reconstruct and describe key features of the ancient chlamydial symbiont. We propose that it was already adapted to an intracellular lifestyle before the emergence of Archaeplastida, and that several observations are compatible with an essential contribution of Chlamydiae to the evolution of algae and plants.
Collapse
Affiliation(s)
- Agathe Subtil
- Institut Pasteur, Unité de Biologie des Interactions Cellulaires, Paris, France; CNRS URA2582, Paris, France.
| | - Astrid Collingro
- University of Vienna, Division of Microbial Ecology, Vienna, Austria
| | - Matthias Horn
- University of Vienna, Division of Microbial Ecology, Vienna, Austria
| |
Collapse
|
63
|
Suwastika IN, Denawa M, Yomogihara S, Im CH, Bang WY, Ohniwa RL, Bahk JD, Takeyasu K, Shiina T. Evidence for lateral gene transfer (LGT) in the evolution of eubacteria-derived small GTPases in plant organelles. FRONTIERS IN PLANT SCIENCE 2014; 5:678. [PMID: 25566271 PMCID: PMC4263083 DOI: 10.3389/fpls.2014.00678] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 11/13/2014] [Indexed: 05/04/2023]
Abstract
The genomes of free-living bacteria frequently exchange genes via lateral gene transfer (LGT), which has played a major role in bacterial evolution. LGT also played a significant role in the acquisition of genes from non-cyanobacterial bacteria to the lineage of "primary" algae and land plants. Small GTPases are widely distributed among prokaryotes and eukaryotes. In this study, we inferred the evolutionary history of organelle-targeted small GTPases in plants. Arabidopsis thaliana contains at least one ortholog in seven subfamilies of OBG-HflX-like and TrmE-Era-EngA-YihA-Septin-like GTPase superfamilies (together referred to as Era-like GTPases). Subcellular localization analysis of all Era-like GTPases in Arabidopsis revealed that all 30 eubacteria-related GTPases are localized to chloroplasts and/or mitochondria, whereas archaea-related DRG and NOG1 are localized to the cytoplasm and nucleus, respectively, suggesting that chloroplast- and mitochondrion-localized GTPases are derived from the ancestral cyanobacterium and α-proteobacterium, respectively, through endosymbiotic gene transfer (EGT). However, phylogenetic analyses revealed that plant organelle GTPase evolution is rather complex. Among the eubacterium-related GTPases, only four localized to chloroplasts (including one dual targeting GTPase) and two localized to mitochondria were derived from cyanobacteria and α-proteobacteria, respectively. Three other chloroplast-targeted GTPases were related to α-proteobacterial proteins, rather than to cyanobacterial GTPases. Furthermore, we found that four other GTPases showed neither cyanobacterial nor α-proteobacterial affiliation. Instead, these GTPases were closely related to clades from other eubacteria, such as Bacteroides (Era1, EngB-1, and EngB-2) and green non-sulfur bacteria (HflX). This study thus provides novel evidence that LGT significantly contributed to the evolution of organelle-targeted Era-like GTPases in plants.
Collapse
Affiliation(s)
- I. Nengah Suwastika
- Graduate School of Biostudies, Kyoto UniversityKyoto, Japan
- Department of Biology, Faculty of Science, Tadulako UniversityPalu, Indonesia
| | - Masatsugu Denawa
- Graduate School of Biostudies, Kyoto UniversityKyoto, Japan
- Graduate School of Medicine, Kyoto UniversityKyoto, Japan
| | - Saki Yomogihara
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural UniversityKyoto, Japan
| | - Chak Han Im
- Division of Life Science (BK21 plus program), Graduate School of Gyeongsang National UniversityJinju, South Korea
| | - Woo Young Bang
- Division of Life Science (BK21 plus program), Graduate School of Gyeongsang National UniversityJinju, South Korea
| | - Ryosuke L. Ohniwa
- Division of Biomedical Science, Faculty of Medicine, University of TsukubaTsukuba, Japan
| | - Jeong Dong Bahk
- Division of Life Science (BK21 plus program), Graduate School of Gyeongsang National UniversityJinju, South Korea
| | - Kunio Takeyasu
- Graduate School of Biostudies, Kyoto UniversityKyoto, Japan
| | - Takashi Shiina
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural UniversityKyoto, Japan
- *Correspondence: Takashi Shiina, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo-nakaragi-cho, Sakyo-ku, Kyoto 606-8522, Japan e-mail:
| |
Collapse
|
64
|
Qiu H, Price DC, Weber APM, Facchinelli F, Yoon HS, Bhattacharya D. Assessing the bacterial contribution to the plastid proteome. TRENDS IN PLANT SCIENCE 2013; 18:680-7. [PMID: 24139901 DOI: 10.1016/j.tplants.2013.09.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 09/11/2013] [Accepted: 09/18/2013] [Indexed: 05/08/2023]
Abstract
Plastids fulfill a variety of different functions (e.g., photosynthesis and amino acid biosynthesis) that rely on proteins of cyanobacterial (i.e., endosymbiont), noncyanobacterial, and 'host' (eukaryotic) origins. Analysis of plastid proteome data from glaucophytes and green algae allows robust inference of protein origins and organelle protein sharing across the >1 billion years of Archaeplastida evolution. Here, we show that more than one-third of genes encoding plastid proteins lack detectable homologs in Cyanobacteria, underlining the taxonomically broad contributions to plastid functions. Chlamydiae and Proteobacteria are the most significant other bacterial sources of plastid proteins. Mapping of plastid proteins to metabolic pathways shows a core set of anciently derived proteins in Archaeplastida, with many others being lineage specific and derived from independent horizontal gene transfer (HGT) events.
Collapse
Affiliation(s)
- Huan Qiu
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, NJ 08540, USA
| | | | | | | | | | | |
Collapse
|
65
|
Facchinelli F, Colleoni C, Ball SG, Weber APM. Chlamydia, cyanobiont, or host: who was on top in the ménage à trois? TRENDS IN PLANT SCIENCE 2013; 18:673-679. [PMID: 24126104 DOI: 10.1016/j.tplants.2013.09.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/13/2013] [Accepted: 09/18/2013] [Indexed: 06/02/2023]
Abstract
The endosymbiont hypothesis proposes that photosynthate from the cyanobiont was exported to the cytosol of the eukaryote host and polymerized from ADP-glucose into glycogen. Chlamydia-like pathogens are the second major source of foreign genes in Archaeplastida, suggesting that these obligate intracellular pathogens had a significant role during the establishment of endosymbiosis, likely through facilitating the metabolic integration between the endosymbiont and the eukaryotic host. In this opinion article, we propose that a hexose phosphate transporter of chlamydial origin was the first transporter responsible for exporting photosynthate out of the cyanobiont. This connection pre-dates the recruitment of the host-derived carbon translocators on the plastid inner membranes of green and red algae, land plants, and photosynthetic organisms of higher order endosymbiotic origin.
Collapse
Affiliation(s)
- Fabio Facchinelli
- Institute for Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-University, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | | | | | | |
Collapse
|
66
|
Facon M, Lin Q, Azzaz AM, Hennen-Bierwagen TA, Myers AM, Putaux JL, Roussel X, D’Hulst C, Wattebled F. Distinct functional properties of isoamylase-type starch debranching enzymes in monocot and dicot leaves. PLANT PHYSIOLOGY 2013; 163:1363-75. [PMID: 24027240 PMCID: PMC3813656 DOI: 10.1104/pp.113.225565] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 09/06/2013] [Indexed: 05/20/2023]
Abstract
Isoamylase-type starch debranching enzymes (ISA) play important roles in starch biosynthesis in chloroplast-containing organisms, as shown by the strict conservation of both catalytically active ISA1 and the noncatalytic homolog ISA2. Functional distinctions exist between species, although they are not understood yet. Numerous plant tissues require both ISA1 and ISA2 for normal starch biosynthesis, whereas monocot endosperm and leaf exhibit nearly normal starch metabolism without ISA2. This study took in vivo and in vitro approaches to determine whether organism-specific physiology or evolutionary divergence between monocots and dicots is responsible for distinctions in ISA function. Maize (Zea mays) ISA1 was expressed in Arabidopsis (Arabidopsis thaliana) lacking endogenous ISA1 or lacking both native ISA1 and ISA2. The maize protein functioned in Arabidopsis leaves to support nearly normal starch metabolism in the absence of any native ISA1 or ISA2. Analysis of recombinant enzymes showed that Arabidopsis ISA1 requires ISA2 as a partner for enzymatic function, whereas maize ISA1 was active by itself. The electrophoretic mobility of recombinant and native maize ISA differed, suggestive of posttranslational modifications in vivo. Sedimentation equilibrium measurements showed recombinant maize ISA1 to be a dimer, in contrast to previous gel permeation data that estimated the molecular mass as a tetramer. These data demonstrate that evolutionary divergence between monocots and dicots is responsible for the distinctions in ISA1 function.
Collapse
|
67
|
Cenci U, Chabi M, Ducatez M, Tirtiaux C, Nirmal-Raj J, Utsumi Y, Kobayashi D, Sasaki S, Suzuki E, Nakamura Y, Putaux JL, Roussel X, Durand-Terrasson A, Bhattacharya D, Vercoutter-Edouart AS, Maes E, Arias MC, Palcic M, Sim L, Ball SG, Colleoni C. Convergent evolution of polysaccharide debranching defines a common mechanism for starch accumulation in cyanobacteria and plants. THE PLANT CELL 2013; 25:3961-75. [PMID: 24163312 PMCID: PMC3877820 DOI: 10.1105/tpc.113.118174] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Starch, unlike hydrosoluble glycogen particles, aggregates into insoluble, semicrystalline granules. In photosynthetic eukaryotes, the transition to starch accumulation occurred after plastid endosymbiosis from a preexisting cytosolic host glycogen metabolism network. This involved the recruitment of a debranching enzyme of chlamydial pathogen origin. The latter is thought to be responsible for removing misplaced branches that would otherwise yield a water-soluble polysaccharide. We now report the implication of starch debranching enzyme in the aggregation of semicrystalline granules of single-cell cyanobacteria that accumulate both glycogen and starch-like polymers. We show that an enzyme of analogous nature to the plant debranching enzyme but of a different bacterial origin was recruited for the same purpose in these organisms. Remarkably, both the plant and cyanobacterial enzymes have evolved through convergent evolution, showing novel yet identical substrate specificities from a preexisting enzyme that originally displayed the much narrower substrate preferences required for glycogen catabolism.
Collapse
Affiliation(s)
- Ugo Cenci
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Malika Chabi
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Mathieu Ducatez
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Catherine Tirtiaux
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Jennifer Nirmal-Raj
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Yoshinori Utsumi
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Daiki Kobayashi
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Satoshi Sasaki
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Eiji Suzuki
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Yasunori Nakamura
- Department of Biological Production, Akita Prefectural University, Akita 010-0195, Japan
| | - Jean-Luc Putaux
- Centre de Recherches sur Les Macromolécules Végétales (Centre National de la Recherche Scientifique), F-38041 Grenoble cedex 9, France (affiliated with Université Joseph Fourier and Member of Institut de Chimie Moléculaire de Grenoble and Insitut Carnot PolyNat)
| | - Xavier Roussel
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Amandine Durand-Terrasson
- Centre de Recherches sur Les Macromolécules Végétales (Centre National de la Recherche Scientifique), F-38041 Grenoble cedex 9, France (affiliated with Université Joseph Fourier and Member of Institut de Chimie Moléculaire de Grenoble and Insitut Carnot PolyNat)
| | - Debashish Bhattacharya
- Department of Ecology, Evolution, and Natural Resources, Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Anne-Sophie Vercoutter-Edouart
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Emmanuel Maes
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Maria Cecilia Arias
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | | | - Lyann Sim
- Carlsberg Laboratory, Copenhagen V DK-1799, Denmark
| | - Steven G. Ball
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
| | - Christophe Colleoni
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, Unité Mixte de Recherche 8576, Centre National de la Recherche Scientifique, Cité Scientifique, 59655 Villeneuve d’Ascq cedex, France
- Address correspondence to
| |
Collapse
|
68
|
Qiu H, Yoon HS, Bhattacharya D. Algal endosymbionts as vectors of horizontal gene transfer in photosynthetic eukaryotes. FRONTIERS IN PLANT SCIENCE 2013; 4:366. [PMID: 24065973 PMCID: PMC3777023 DOI: 10.3389/fpls.2013.00366] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 08/28/2013] [Indexed: 05/08/2023]
Abstract
Photosynthesis in eukaryotes occurs in the plastid, an organelle that is derived from a single cyanobacterial primary endosymbiosis in the common ancestor of the supergroup Plantae (or Archaeplastida) that includes green, red, and glaucophyte algae and plants. However a variety of other phytoplankton such as the chlorophyll c-containing diatoms, dinoflagellates, and haptophytes contain a red alga-derived plastid that traces its origin to secondary or tertiary (eukaryote engulfs eukaryote) endosymbiosis. The hypothesis of Plantae monophyly has only recently been substantiated, however the extent and role of endosymbiotic and horizontal gene transfer (EGT and HGT) in algal genome evolution still remain to be fully understood. What is becoming clear from analysis of complete genome data is that algal gene complements can no longer be considered essentially eukaryotic in provenance; i.e., with the expected addition of several hundred cyanobacterial genes derived from EGT and a similar number derived from the mitochondrial ancestor. For example, we now know that foreign cells such as Chlamydiae and other prokaryotes have made significant contributions to plastid functions in Plantae. Perhaps more surprising is the recent finding of extensive bacterium-derived HGT in the nuclear genome of the unicellular red alga Porphyridium purpureum that does not relate to plastid functions. These non-endosymbiont gene transfers not only shaped the evolutionary history of Plantae but also were propagated via secondary endosymbiosis to a multitude of other phytoplankton. Here we discuss the idea that Plantae (in particular red algae) are one of the major players in eukaryote genome evolution by virtue of their ability to act as "sinks" and "sources" of foreign genes through HGT and endosymbiosis, respectively. This hypothesis recognizes the often under-appreciated Rhodophyta as major sources of genetic novelty among photosynthetic eukaryotes.
Collapse
Affiliation(s)
- Huan Qiu
- Department of Ecology, Evolution, and Natural Resources, Institute of Marine and Coastal Science, Rutgers UniversityNew Brunswick, NJ, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan UniversitySuwon, South Korea
| | - Debashish Bhattacharya
- Department of Ecology, Evolution, and Natural Resources, Institute of Marine and Coastal Science, Rutgers UniversityNew Brunswick, NJ, USA
- *Correspondence: Debashish Bhattacharya, Department of Ecology, Evolution, and Natural Resources, Institute of Marine and Coastal Science, Rutgers University, 59 Dudley Road, Foran Hall 102, New Brunswick, NJ 08901, USA e-mail:
| |
Collapse
|
69
|
Abstract
Using the repeat finding algorithm FT-Rep, we have identified 154 pentatricopeptide repeat (PPR) proteins in nine fully sequenced genomes from green algae (with a total of 1201 repeats) and grouped them in 47 orthologous groups. All data are available in a database, PPRdb, accessible online at http://giavap-genomes.ibpc.fr/ppr. Based on phylogenetic trees generated from the repeats, we propose evolutionary scenarios for PPR proteins. Two PPRs are clearly conserved in the entire green lineage: MRL1 is a stabilization factor for the rbcL mRNA, while HCF152 binds in plants to the psbH-petB intergenic region. MCA1 (the stabilization factor for petA) and PPR7 (a short PPR also acting on chloroplast mRNAs) are conserved across the entire Chlorophyta. The other PPRs are clade-specific, with evidence for gene losses, duplications, and horizontal transfer. In some PPR proteins, an additional domain found at the C terminus provides clues as to possible functions. PPR19 and PPR26 possess a methyltransferase_4 domain suggesting involvement in RNA guanosine methylation. PPR18 contains a C-terminal CBS domain, similar to the CBSPPR1 protein found in nucleoids. PPR16, PPR29, PPR37, and PPR38 harbor a SmR (MutS-related) domain similar to that found in land plants pTAC2, GUN1, and SVR7. The PPR-cyclins PPR3, PPR4, and PPR6, in addition, contain a cyclin domain C-terminal to their SmR domain. PPR31 is an unusual PPR-cyclin containing at its N terminus an OctotricoPeptide Repeat (OPR) and a RAP domain. We consider the possibility that PPR proteins with a SmR domain can introduce single-stranded nicks in the plastid chromosome.
Collapse
Affiliation(s)
- Nicolas J Tourasse
- UMR 7141 CNRS/UPMC; Institut de Biologie Physico-Chimique; F-75005 Paris, France
| | - Yves Choquet
- UMR 7141 CNRS/UPMC; Institut de Biologie Physico-Chimique; F-75005 Paris, France
| | - Olivier Vallon
- UMR 7141 CNRS/UPMC; Institut de Biologie Physico-Chimique; F-75005 Paris, France
| |
Collapse
|
70
|
Lagkouvardos I, Weinmaier T, Lauro FM, Cavicchioli R, Rattei T, Horn M. Integrating metagenomic and amplicon databases to resolve the phylogenetic and ecological diversity of the Chlamydiae. ISME JOURNAL 2013; 8:115-25. [PMID: 23949660 DOI: 10.1038/ismej.2013.142] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 07/12/2013] [Accepted: 07/16/2013] [Indexed: 11/09/2022]
Abstract
In the era of metagenomics and amplicon sequencing, comprehensive analyses of available sequence data remain a challenge. Here we describe an approach exploiting metagenomic and amplicon data sets from public databases to elucidate phylogenetic diversity of defined microbial taxa. We investigated the phylum Chlamydiae whose known members are obligate intracellular bacteria that represent important pathogens of humans and animals, as well as symbionts of protists. Despite their medical relevance, our knowledge about chlamydial diversity is still scarce. Most of the nine known families are represented by only a few isolates, while previous clone library-based surveys suggested the existence of yet uncharacterized members of this phylum. Here we identified more than 22,000 high quality, non-redundant chlamydial 16S rRNA gene sequences in diverse databases, as well as 1900 putative chlamydial protein-encoding genes. Even when applying the most conservative approach, clustering of chlamydial 16S rRNA gene sequences into operational taxonomic units revealed an unexpectedly high species, genus and family-level diversity within the Chlamydiae, including 181 putative families. These in silico findings were verified experimentally in one Antarctic sample, which contained a high diversity of novel Chlamydiae. In our analysis, the Rhabdochlamydiaceae, whose known members infect arthropods, represents the most diverse and species-rich chlamydial family, followed by the protist-associated Parachlamydiaceae, and a putative new family (PCF8) with unknown host specificity. Available information on the origin of metagenomic samples indicated that marine environments contain the majority of the newly discovered chlamydial lineages, highlighting this environment as an important chlamydial reservoir.
Collapse
Affiliation(s)
- Ilias Lagkouvardos
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Thomas Weinmaier
- Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Federico M Lauro
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Ricardo Cavicchioli
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Thomas Rattei
- Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Matthias Horn
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| |
Collapse
|
71
|
Baluška F, Mancuso S. Microorganism and filamentous fungi drive evolution of plant synapses. Front Cell Infect Microbiol 2013; 3:44. [PMID: 23967407 PMCID: PMC3744040 DOI: 10.3389/fcimb.2013.00044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 07/26/2013] [Indexed: 12/23/2022] Open
Abstract
In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and symbiotic microorganisms. These microorganisms are the driving force behind the evolution of plant synapses and other neuronal aspects of higher plants; this is especially pronounced in the root apices. Plant synapses allow synaptic cell–cell communication and coordination in plants, as well as sensory-motor integration in root apices searching for water and mineral nutrition. These neuronal aspects of higher plants are closely linked with their unique ability to adapt to environmental changes.
Collapse
Affiliation(s)
- František Baluška
- IZMB, Department of Plant Cell Biology, University of Bonn Bonn, Germany.
| | | |
Collapse
|
72
|
Facchinelli F, Pribil M, Oster U, Ebert NJ, Bhattacharya D, Leister D, Weber APM. Proteomic analysis of the Cyanophora paradoxa muroplast provides clues on early events in plastid endosymbiosis. PLANTA 2013; 237:637-51. [PMID: 23212214 DOI: 10.1007/s00425-012-1819-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 11/08/2012] [Indexed: 05/06/2023]
Abstract
Glaucophytes represent the first lineage of photosynthetic eukaryotes of primary endosymbiotic origin that diverged after plastid establishment. The muroplast of Cyanophora paradoxa represents a primitive plastid that resembles its cyanobacterial ancestor in pigment composition and the presence of a peptidoglycan wall. To attain insights into the evolutionary history of cyanobiont integration and plastid development, it would thus be highly desirable to obtain knowledge on the composition of the glaucophyte plastid proteome. Here, we provide the first proteomic analysis of the muroplast of C. paradoxa. Mass spectrometric analysis of the muroplast proteome identified 510 proteins with high confidence. The protein repertoire of the muroplast revealed novel paths for reduced carbon flow and export to the cytosol through a sugar phosphate transporter of chlamydial origin. We propose that C. paradoxa possesses a primordial plastid mirroring the situation in the early protoalga.
Collapse
Affiliation(s)
- Fabio Facchinelli
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences, Heinrich-Heine-University, Universitätsstraße 1, Düsseldorf, Germany
| | | | | | | | | | | | | |
Collapse
|
73
|
Abstract
The idea of an endosymbiotic origin of plastids has become incontrovertible, but many important aspects of plastid origins remain obscured in the mists of more than a billion years of evolutionary history. This commentary provides a critical summary of a recent proposal that primary plastid endosymbiosis was facilitated by the secretion into the host cytosol of effector proteins from intracellular Chlamydiales pathogens that allowed the host to utilize carbohydrates exported from the incipient plastid. Although not without flaws, the model provides an explanation for why primary plastids have evolved so rarely and why Archaeplastida, among all phagotrophic eukaryotes, succeeded in establishing primary plastids.
Collapse
Affiliation(s)
- David Baum
- Department of Botany, University of Wisconsin, Madison, Wisconsin 53706, USA.
| |
Collapse
|