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Brunet T, Booth DS. Cell polarity in the protist-to-animal transition. Curr Top Dev Biol 2023; 154:1-36. [PMID: 37100515 DOI: 10.1016/bs.ctdb.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
A signature feature of the animal kingdom is the presence of epithelia: sheets of polarized cells that both insulate the organism from its environment and mediate interactions with it. Epithelial cells display a marked apico-basal polarity, which is highly conserved across the animal kingdom, both in terms of morphology and of molecular regulators. How did this architecture first evolve? Although the last eukaryotic common ancestor almost certainly possessed a simple form of apico-basal polarity (marked by the presence of one or several flagella at a single cellular pole), comparative genomics and evolutionary cell biology reveal that the polarity regulators of animal epithelial cells have a surprisingly complex and stepwise evolutionary history. Here, we retrace their evolutionary assembly. We suggest that the "polarity network" that polarized animal epithelial cells evolved by integration of initially independent cellular modules that evolved at distinct steps of our evolutionary ancestry. The first module dates back to the last common ancestor of animals and amoebozoans and involved Par1, extracellular matrix proteins, and the integrin-mediated adhesion complex. Other regulators, such as Cdc42, Dlg, Par6 and cadherins evolved in ancient unicellular opisthokonts, and might have first been involved in F-actin remodeling and filopodial dynamics. Finally, the bulk of "polarity proteins" as well as specialized adhesion complexes evolved in the metazoan stem-line, in concert with the newly evolved intercellular junctional belts. Thus, the polarized architecture of epithelia can be understood as a palimpsest of components of distinct histories and ancestral functions, which have become tightly integrated in animal tissues.
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Cavalier-Smith T. Ciliary transition zone evolution and the root of the eukaryote tree: implications for opisthokont origin and classification of kingdoms Protozoa, Plantae, and Fungi. PROTOPLASMA 2022; 259:487-593. [PMID: 34940909 PMCID: PMC9010356 DOI: 10.1007/s00709-021-01665-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 05/03/2021] [Indexed: 05/19/2023]
Abstract
I thoroughly discuss ciliary transition zone (TZ) evolution, highlighting many overlooked evolutionarily significant ultrastructural details. I establish fundamental principles of TZ ultrastructure and evolution throughout eukaryotes, inferring unrecognised ancestral TZ patterns for Fungi, opisthokonts, and Corticata (i.e., kingdoms Plantae and Chromista). Typical TZs have a dense transitional plate (TP), with a previously overlooked complex lattice as skeleton. I show most eukaryotes have centriole/TZ junction acorn-V filaments (whose ancestral function was arguably supporting central pair microtubule-nucleating sites; I discuss their role in centriole growth). Uniquely simple malawimonad TZs (without TP, simpler acorn) pinpoint the eukaryote tree's root between them and TP-bearers, highlighting novel superclades. I integrate TZ/ciliary evolution with the best multiprotein trees, naming newly recognised major eukaryote clades and revise megaclassification of basal kingdom Protozoa. Recent discovery of non-photosynthetic phagotrophic flagellates with genome-free plastids (Rhodelphis), the sister group to phylum Rhodophyta (red algae), illuminates plant and chromist early evolution. I show previously overlooked marked similarities in cell ultrastructure between Rhodelphis and Picomonas, formerly considered an early diverging chromist. In both a nonagonal tube lies between their TP and an annular septum surrounding their 9+2 ciliary axoneme. Mitochondrial dense condensations and mitochondrion-linked smooth endomembrane cytoplasmic partitioning cisternae further support grouping Picomonadea and Rhodelphea as new plant phylum Pararhoda. As Pararhoda/Rhodophyta form a robust clade on site-heterogeneous multiprotein trees, I group Pararhoda and Rhodophyta as new infrakingdom Rhodaria of Plantae within subkingdom Biliphyta, which also includes Glaucophyta with fundamentally similar TZ, uniquely in eukaryotes. I explain how biliphyte TZs generated viridiplant stellate-structures.
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Nabais C, Pessoa D, de-Carvalho J, van Zanten T, Duarte P, Mayor S, Carneiro J, Telley IA, Bettencourt-Dias M. Plk4 triggers autonomous de novo centriole biogenesis and maturation. J Cell Biol 2021; 220:211915. [PMID: 33760919 PMCID: PMC7995200 DOI: 10.1083/jcb.202008090] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/14/2020] [Accepted: 02/18/2021] [Indexed: 12/23/2022] Open
Abstract
Centrioles form centrosomes and cilia. In most proliferating cells, centrioles assemble through canonical duplication, which is spatially, temporally, and numerically regulated by the cell cycle and the presence of mature centrioles. However, in certain cell types, centrioles assemble de novo, yet by poorly understood mechanisms. Herein, we established a controlled system to investigate de novo centriole biogenesis, using Drosophila melanogaster egg explants overexpressing Polo-like kinase 4 (Plk4), a trigger for centriole biogenesis. We show that at a high Plk4 concentration, centrioles form de novo, mature, and duplicate, independently of cell cycle progression and of the presence of other centrioles. Plk4 concentration determines the temporal onset of centriole assembly. Moreover, our results suggest that distinct biochemical kinetics regulate de novo and canonical biogenesis. Finally, we investigated which other factors modulate de novo centriole assembly and found that proteins of the pericentriolar material (PCM), and in particular γ-tubulin, promote biogenesis, likely by locally concentrating critical components.
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Affiliation(s)
| | | | | | | | - Paulo Duarte
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Satyajit Mayor
- National Centre for Biological Sciences, Bangalore, India
| | | | - Ivo A Telley
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
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Lindemann CB, Lesich KA. The many modes of flagellar and ciliary beating: Insights from a physical analysis. Cytoskeleton (Hoboken) 2021; 78:36-51. [PMID: 33675288 PMCID: PMC8048621 DOI: 10.1002/cm.21656] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 12/18/2022]
Abstract
The mechanism that allows the axoneme of eukaryotic cilia and flagella to produce both helical and planar beating is an enduring puzzle. The nine outer doublets of eukaryotic cilia and flagella are arranged in a circle. Therefore, each doublet pair with its associated dynein motors, should produce torque to bend the flagellum in a different direction. Sequential activation of each doublet pair should, therefore result in a helical bending wave. In reality, most cilia and flagella have a well‐defined bending plane and many exhibit an almost perfectly flat (planar) beating pattern. In this analysis we examine the physics that governs flagellar bending, and arrive at two distinct possibilities that could explain the mechanism of planar beating. Of these, the mechanism with the best observational support is that the flagellum behaves as two ribbons of doublets interacting with a central partition. We also examine the physics of torsion in flagella and conclude that torsion could play a role in transitioning from a planar to a helical beating modality in long flagella. Lastly, we suggest some tests that would provide theoretical and/or experimental evaluation of our proposals.
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Affiliation(s)
- Charles B Lindemann
- Department of Biological Sciences, Oakland University, Rochester, Michigan, USA
| | - Kathleen A Lesich
- Department of Biological Sciences, Oakland University, Rochester, Michigan, USA
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Kaczmarska I, Ehrman JM. Enlarge or die! An auxospore perspective on diatom diversification. ORG DIVERS EVOL 2021. [DOI: 10.1007/s13127-020-00476-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Exploring Molecular Signs of Sex in the Marine Diatom Skeletonema marinoi. Genes (Basel) 2019; 10:genes10070494. [PMID: 31261777 PMCID: PMC6678668 DOI: 10.3390/genes10070494] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 06/14/2019] [Accepted: 06/24/2019] [Indexed: 11/17/2022] Open
Abstract
Sexual reproduction plays a fundamental role in diatom life cycles. It contributes to increasing genetic diversity through meiotic recombination and also represents the phase where large-sized cells are produced to counteract the cell size reduction process that characterizes these microalgae. With the aim to identify genes linked to the sexual phase of the centric planktonic diatom Skeletonema marinoi, we carried out an RNA-seq experiment comparing the expression level of transcripts in sexualized cells with that of large cells not competent for sex. A set of genes involved in meiosis were found upregulated. Despite the fact that flagellate gametes were observed in the sample, we did not detect the expression of genes involved in the synthesis of flagella that were upregulated during sexual reproduction in another centric diatom. A comparison with the set of genes changing during the first phases of sexual reproduction of the pennate diatom Pseudo-nitzschia multistriata revealed the existence of commonalities, including the strong upregulation of genes with an unknown function that we named Sex Induced Genes (SIG). Our results further broadened the panel of genes that can be used as a marker for sexual reproduction of diatoms, crucial for the interpretation of metatranscriptomic datasets.
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Yamada K, Nagasato C, Motomura T, Ichinomiya M, Kuwata A, Kamiya M, Ohki K, Yoshikawa S. Mitotic spindle formation in Triparma laevis NIES-2565(Parmales, Heterokontophyta). PROTOPLASMA 2017; 254:461-471. [PMID: 27048177 DOI: 10.1007/s00709-016-0967-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 03/23/2016] [Indexed: 06/05/2023]
Abstract
The parmalean algae possess a siliceous wall and represent the sister lineage of diatoms; they are thought to be a key group for understanding the evolution of diatoms. Diatoms possess well-characterized and unique mitotic structures, but the mitotic apparatus of Parmales is still unknown. We observed the microtubule (MT) array during interphase and mitosis in Triparma laevis using TEM. The interphase cells had four or five centrioles (∼80 nm in length), from which MTs emanated toward the cytoplasm. In prophase, the bundle of MTs arose at an extranuclear site. The position of centrioles with respect to an MT bundle changed during its elongation. Centrioles were observed on the lateral side of a shorter MT bundle (∼590 nm) and on either side of an extended MT bundle (∼700 nm). In metaphase, the spindle consisted of two types of MTs-MT bundle that passed through a cytoplasmic tunnel in the center of the nucleus and single MTs (possibly kinetochore MTs) that extended from the poles into the nucleus. The nuclear envelope disappeared only at the regions where the kinetochore MTs penetrated. In telophase, daughter chromosomes migrated toward opposite poles, and the MT bundle was observed between segregating chromosomes. These observations showed that MT nucleation does not always occur at the periphery of centrioles through cell cycle and that the spindle of T. laevis has a similar configuration to that of diatoms.
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Affiliation(s)
- Kazumasa Yamada
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0003, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0003, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0003, Japan
| | - Mutsuo Ichinomiya
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Higashi, 862-8502, Japan
| | - Akira Kuwata
- Tohoku National Fisheries Research Institute, Shiogama, 985-0001, Japan
| | - Mitsunobu Kamiya
- Faculty of Marine Bioscience, Fukui Prefectural University, Obama, 917-0003, Japan
| | - Kaori Ohki
- Faculty of Marine Bioscience, Fukui Prefectural University, Obama, 917-0003, Japan
| | - Shinya Yoshikawa
- Faculty of Marine Bioscience, Fukui Prefectural University, Obama, 917-0003, Japan.
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Fu G, Nagasato C, Yamagishi T, Kawai H, Okuda K, Takao Y, Horiguchi T, Motomura T. Ubiquitous distribution of helmchrome in phototactic swarmers of the stramenopiles. PROTOPLASMA 2016; 253:929-941. [PMID: 26202473 DOI: 10.1007/s00709-015-0857-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/13/2015] [Indexed: 12/16/2023]
Abstract
Most swarmers (swimming cells) of the stramenopile group, ranging from unicellular protist to giant kelps (brown algae), have two heterogeneous flagella: a long anterior flagellum (AF) and a relatively shorter posterior flagellum (PF). These flagellated cells often exhibit phototaxis upon light stimulation, although the mechanism by which how the phototactic response is regulated remains largely unknown. A flavoprotein concentrating at the paraflagellar body (PFB) on the basal part of the PF, which can emit green autofluorescence under blue light irradiance, has been proposed as a possible blue light photoreceptor for brown algal phototaxis although the nature of the flavoprotein still remains elusive. Recently, we identified helmchrome as a PF-specific flavoprotein protein in a LC-MS/MS-based proteomics study of brown algal flagella (Fu et al. 2014). To verify the conservation of helmchrome, in the present study, the absence or presence and the localization of helmchrome in swarmers of various algal species were investigated. The results showed that helmchrome was only detected in phototactic swarmers but not the non-phototactic ones of the stramenopile group. Electron microscopy further revealed that the helmchrome detectable swarmers bear a conserved PFB-eyespot complex, which may serve as structural basis for light sensing. It is speculated that all three conserved properties: helmchrome, the PFB structure, and the eyespot apparatus, will be essential parts for phototaxis of stramenopile swarmers.
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Affiliation(s)
- Gang Fu
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan
| | - Takahiro Yamagishi
- Research Center for Inland Seas, Kobe University, Rokkodai, Nadaku, Kobe, 657-8501, Japan
| | - Hiroshi Kawai
- Research Center for Inland Seas, Kobe University, Rokkodai, Nadaku, Kobe, 657-8501, Japan
| | - Kazuo Okuda
- Graduate School of Integrated Arts and Sciences, Kochi University, Kochi, 780-8520, Japan
| | - Yoshitake Takao
- Faculty of Marine Bioscience, Fukui Prefectural University, Obama, 917-0003, Japan
| | - Takeo Horiguchi
- Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan.
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A paneukaryotic genomic analysis of the small GTPase RABL2 underscores the significance of recurrent gene loss in eukaryote evolution. Biol Direct 2016; 11:5. [PMID: 26832778 PMCID: PMC4736243 DOI: 10.1186/s13062-016-0107-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 01/27/2016] [Indexed: 12/30/2022] Open
Abstract
Background The cilium (flagellum) is a complex cellular structure inherited from the last eukaryotic common ancestor (LECA). A large number of ciliary proteins have been characterized in a few model organisms, but their evolutionary history often remains unexplored. One such protein is the small GTPase RABL2, recently implicated in the assembly of the sperm tail in mammals. Results Using the wealth of currently available genome and transcriptome sequences, including data from our on-going sequencing projects, we systematically analyzed the phylogenetic distribution and evolutionary history of RABL2 orthologs. Our dense taxonomic sampling revealed the presence of RABL2 genes in nearly all major eukaryotic lineages, including small “obscure” taxa such as breviates, ancyromonads, malawimonads, jakobids, picozoans, or palpitomonads. The phyletic pattern of RABL2 genes indicates that it was present already in the LECA. However, some organisms lack RABL2 as a result of secondary loss and our present sampling predicts well over 30 such independent events during the eukaryote evolution. The distribution of RABL2 genes correlates with the presence/absence of cilia: not a single well-established cilium-lacking species has retained a RABL2 ortholog. However, several ciliated taxa, most notably nematodes, some arthropods and platyhelminths, diplomonads, and ciliated subgroups of apicomplexans and embryophytes, lack RABL2 as well, suggesting some simplification in their cilium-associated functions. On the other hand, several algae currently unknown to form cilia, e.g., the “prasinophytes” of the genus Prasinoderma or the ochrophytes Pelagococcus subviridis and Pinguiococcus pyrenoidosus, turned out to encode not only RABL2, but also homologs of some hallmark ciliary proteins, suggesting the existence of a cryptic flagellated stage in their life cycles. We additionally obtained insights into the evolution of the RABL2 gene architecture, which seems to have ancestrally consisted of eight exons subsequently modified not only by lineage-specific intron loss and gain, but also by recurrent loss of the terminal exon encoding a poorly conserved C-terminal extension. Conclusions Our comparative analysis supports the notion that RABL2 is an ancestral component of the eukaryotic cilium and underscores the still underappreciated magnitude of recurrent gene loss, or reductive evolution in general, in the history of eukaryotic genomes and cells. Reviewers This article was reviewed by Berend Snel and James O. McInerney. Electronic supplementary material The online version of this article (doi:10.1186/s13062-016-0107-8) contains supplementary material, which is available to authorized users.
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Actin, actin-related proteins and profilin in diatoms: A comparative genomic analysis. Mar Genomics 2015; 23:133-42. [DOI: 10.1016/j.margen.2015.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 06/30/2015] [Accepted: 07/02/2015] [Indexed: 12/24/2022]
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Idei M, Sato S, Nagasato C, Motomura T, Toyoda K, Nagumo T, Mann DG. Spermatogenesis and auxospore structure in the multipolar centric diatom Hydrosera. JOURNAL OF PHYCOLOGY 2015; 51:144-158. [PMID: 26986265 DOI: 10.1111/jpy.12261] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 11/18/2014] [Indexed: 06/05/2023]
Abstract
Spermatogenesis and auxospore development were studied in the freshwater centric diatom Hydrosera triquetra. Spermatogenesis was unusual, lacking depauperating cell divisions within the spermatogonangium. Instead, a series of mitoses occurred within an undivided cell to produce a multinucleate plasmodium with peripheral nuclei, which then underwent meiosis. 32 or 64 sperm budded off from the plasmodium leaving a large residual cell containing all the chloroplasts. Similar development apparently occurs in Pleurosira, Aulacodiscus, and Guinardia, these being so distantly related that independent evolution of plasmodial spermatogenesis seems likely. After presumed fertilization, the Hydrosera egg cell expanded distally to form a triangular end part. However, unlike in other triangular diatoms (Lithodesmium, Triceratium), the development of triradiate symmetry was not controlled by the "canonical" method of a perizonium that constrains expansion to small terminal areas of the auxospore wall. Instead, the auxospore wall lacked a perizonium and possessed only scales and a dense mat of thin, apparently entangled strips of imperforate silica. No such structures have been reported from any other centric diatoms, the closest analogs being instead the incunabular strips of some raphid diatoms (Nitzschia and Pinnularia). Whether these silica structures are formed by the normal method (intracellular deposition within a silica deposition vesicle) is unknown. As well as being more rounded than vegetative cells, the initial cell is aberrant in its structure, since it has a less polarized distribution of the "triptych" pores characteristic of the species.
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Affiliation(s)
- Masahiko Idei
- Bunkyo University, 3337 Minami-ogishima, Koshigaya-shi, Saitama, 343-8851, Japan
| | - Shinya Sato
- Fukui Prefectural University, 1-1 Gakuen-cho, Obama, Fukui, 917-0003, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0003, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0003, Japan
| | - Kensuke Toyoda
- Department of Biology, Keio University, Yokohama, Kanagawa, 223-8521, Japan
| | - Tamotsu Nagumo
- The Nippon Dental University, Chiyoda-ku, Tokyo, 102-8159, Japan
| | - David G Mann
- Royal Botanic Garden Edinburgh, Edinburgh, EH3 5LR, UK
- Aquatic Ecosystems, Institute for Food and Agricultural Research and Technology (IRTA), Crta de Poble Nou Km 5.5, Sant Carles de la Ràpita, Catalunya, E-43540, Spain
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Moran J, McKean PG, Ginger ML. Eukaryotic Flagella: Variations in Form, Function, and Composition during Evolution. Bioscience 2014. [DOI: 10.1093/biosci/biu175] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Cavalier-Smith T. The neomuran revolution and phagotrophic origin of eukaryotes and cilia in the light of intracellular coevolution and a revised tree of life. Cold Spring Harb Perspect Biol 2014; 6:a016006. [PMID: 25183828 PMCID: PMC4142966 DOI: 10.1101/cshperspect.a016006] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Three kinds of cells exist with increasingly complex membrane-protein targeting: Unibacteria (Archaebacteria, Posibacteria) with one cytoplasmic membrane (CM); Negibacteria with a two-membrane envelope (inner CM; outer membrane [OM]); eukaryotes with a plasma membrane and topologically distinct endomembranes and peroxisomes. I combine evidence from multigene trees, palaeontology, and cell biology to show that eukaryotes and archaebacteria are sisters, forming the clade neomura that evolved ~1.2 Gy ago from a posibacterium, whose DNA segregation and cell division were destabilized by murein wall loss and rescued by the evolving novel neomuran endoskeleton, histones, cytokinesis, and glycoproteins. Phagotrophy then induced coevolving serial major changes making eukaryote cells, culminating in two dissimilar cilia via a novel gliding-fishing-swimming scenario. I transfer Chloroflexi to Posibacteria, root the universal tree between them and Heliobacteria, and argue that Negibacteria are a clade whose OM, evolving in a green posibacterium, was never lost.
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Fu G, Nagasato C, Oka S, Cock JM, Motomura T. Proteomics analysis of heterogeneous flagella in brown algae (stramenopiles). Protist 2014; 165:662-75. [PMID: 25150613 DOI: 10.1016/j.protis.2014.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/22/2014] [Accepted: 07/22/2014] [Indexed: 10/25/2022]
Abstract
Flagella are conserved organelles among eukaryotes and they are composed of many proteins, which are necessary for flagellar assembly, maintenance and function. Stramenopiles, which include brown algae, diatoms and oomycetes, possess two laterally inserted flagella. The anterior flagellum (AF) extends forward and bears tripartite mastigonemes, whilst the smooth posterior flagellum (PF) often has a paraflagellar body structure. These heterogeneous flagella have served as crucial structures in algal studies especially from a viewpoint of phylogeny. However, the protein compositions of the flagella are still largely unknown. Here we report a LC-MS/MS based proteomics analysis of brown algal flagella. In total, 495 flagellar proteins were identified. Functional annotation of the proteome data revealed that brown algal flagellar proteins were associated with cell motility, signal transduction and various metabolic activities. We separately isolated AF and PF and analyzed their protein compositions. This analysis led to the identification of several AF- and PF-specific proteins. Among the PF-specific proteins, we found a candidate novel blue light receptor protein involved in phototaxis, and named it HELMCHROME because of the steering function of PF. Immunological analysis revealed that this protein was localized along the whole length of the PF and concentrated in the paraflagellar body.
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Affiliation(s)
- Gang Fu
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran 051-0013, Hokkaido, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran 051-0013, Hokkaido, Japan
| | - Seiko Oka
- Instrumental Analysis Division, Equipment Management Center, Creative Research Institution, Hokkaido University, Sapporo 001-0021, Hokkaido, Japan
| | - J Mark Cock
- University Pierre et Marie Curie and Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7139, Laboratoire International Associé Dispersal and Adaptation in Marine Species, Station Biologique de Roscoff, 29682 Roscoff Cedex, France
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran 051-0013, Hokkaido, Japan.
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Nick P. You need to see what you want to understand--ultrastructure helps to uncover the mysteries of early life. PROTOPLASMA 2013; 250:797-798. [PMID: 23900778 DOI: 10.1007/s00709-013-0523-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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