1
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Anami S, Yamashino T, Kikuchi H, Suzuki R, Aoki S. Nuclear interactions between the Pseudo-Response Regulator clock proteins and the Multi-Step Phosphorelay mediator Histidine-containing phosphotransfers in the moss Physcomitrium patens. Biochem Biophys Res Commun 2024; 733:150734. [PMID: 39332156 DOI: 10.1016/j.bbrc.2024.150734] [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: 09/18/2024] [Revised: 09/19/2024] [Accepted: 09/20/2024] [Indexed: 09/29/2024]
Abstract
Pseudo-Response Regulator (PRR) proteins constitute a fundamental set of circadian clock components in plants. PRRs have an amino acid sequence stretch with similarity to the receiver (REC) domain of response regulators (RRs) in the Multi-Step Phosphorelay (MSP). However, it has never been elucidated whether PRRs interact with Histidine-containing Phosphotransfer (HPt) proteins, which transfer a phosphate to RRs. Here, we studied whether PRRs interact with HPts in the moss Physcomitrium patens by the Yeast Two-Hybrid system and Bimolecular Fluorescence Complementation. P. patens PRR1/2/3 interacted with HPt1/2 in the nucleus, but not with HPt3, suggesting that P. patens PRRs function as authentic RRs. We discuss these results in relation to the evolution and diversity of the plant circadian clocks.
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Affiliation(s)
- Shu Anami
- Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Takafumi Yamashino
- Graduate School of Bioagriculture, Nagoya University, Furo- Cho, Chikusa-ku, Nagoya, 464-8601, Japan.
| | - Haruki Kikuchi
- Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Ryo Suzuki
- Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Setsuyuki Aoki
- Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
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2
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Romeiro Motta M, Nédélec F, Saville H, Woelken E, Jacquerie C, Pastuglia M, Stolze SC, Van De Slijke E, Böttger L, Belcram K, Nakagami H, De Jaeger G, Bouchez D, Schnittger A. The cell cycle controls spindle architecture in Arabidopsis by activating the augmin pathway. Dev Cell 2024:S1534-5807(24)00484-2. [PMID: 39191252 DOI: 10.1016/j.devcel.2024.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 05/25/2024] [Accepted: 08/05/2024] [Indexed: 08/29/2024]
Abstract
To ensure an even segregation of chromosomes during somatic cell division, eukaryotes rely on mitotic spindles. Here, we measured prime characteristics of the Arabidopsis mitotic spindle and built a three-dimensional dynamic model using Cytosim. We identified the cell-cycle regulator CYCLIN-DEPENDENT KINASE B1 (CDKB1) together with its cyclin partner CYCB3;1 as key regulators of spindle morphology in Arabidopsis. We found that the augmin component ENDOSPERM DEFECTIVE1 (EDE1) is a substrate of the CDKB1;1-CYCB3;1 complex. A non-phosphorylatable mutant rescue of ede1 resembled the spindle phenotypes of cycb3;1 and cdkb1 mutants and the protein associated less efficiently with spindle microtubules. Accordingly, reducing the level of augmin in simulations recapitulated the phenotypes observed in the mutants. Our findings emphasize the importance of cell-cycle-dependent phospho-control of the mitotic spindle in plant cells and support the validity of our model as a framework for the exploration of mechanisms controlling the organization of the eukaryotic spindle.
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Affiliation(s)
- Mariana Romeiro Motta
- Department of Developmental Biology, Institute for Plant Sciences and Microbiology, University of Hamburg, Hamburg 22609, Germany; Laboratoire de Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon 69007, France
| | - François Nédélec
- Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, UK.
| | - Helen Saville
- Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, UK
| | - Elke Woelken
- Department of Aquatic Ecophysiology and Phycology, Institute for Plant Sciences and Microbiology, University of Hamburg, Hamburg 22609, Germany
| | - Claire Jacquerie
- Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, UK
| | - Martine Pastuglia
- Institute Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles 78026, France
| | | | - Eveline Van De Slijke
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium; Vlaams Instituut voor Biotechnologie (VIB) Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Lev Böttger
- Department of Developmental Biology, Institute for Plant Sciences and Microbiology, University of Hamburg, Hamburg 22609, Germany
| | - Katia Belcram
- Institute Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles 78026, France
| | - Hirofumi Nakagami
- Max-Planck-Institute for Plant Breeding Research, Cologne 50829, Germany
| | - Geert De Jaeger
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium; Vlaams Instituut voor Biotechnologie (VIB) Center for Plant Systems Biology, Ghent 9052, Belgium
| | - David Bouchez
- Institute Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles 78026, France
| | - Arp Schnittger
- Department of Developmental Biology, Institute for Plant Sciences and Microbiology, University of Hamburg, Hamburg 22609, Germany.
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3
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Kiyomitsu A, Nishimura T, Hwang SJ, Ansai S, Kanemaki MT, Tanaka M, Kiyomitsu T. Ran-GTP assembles a specialized spindle structure for accurate chromosome segregation in medaka early embryos. Nat Commun 2024; 15:981. [PMID: 38302485 PMCID: PMC10834446 DOI: 10.1038/s41467-024-45251-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 01/19/2024] [Indexed: 02/03/2024] Open
Abstract
Despite drastic cellular changes during cleavage, a mitotic spindle assembles in each blastomere to accurately segregate duplicated chromosomes. Mechanisms of mitotic spindle assembly have been extensively studied using small somatic cells. However, mechanisms of spindle assembly in large vertebrate embryos remain little understood. Here, we establish functional assay systems in medaka (Oryzias latipes) embryos by combining CRISPR knock-in with auxin-inducible degron technology. Live imaging reveals several unexpected features of microtubule organization and centrosome positioning that achieve rapid, accurate cleavage. Importantly, Ran-GTP assembles a dense microtubule network at the metaphase spindle center that is essential for chromosome segregation in early embryos. This unique spindle structure is remodeled into a typical short, somatic-like spindle after blastula stages, when Ran-GTP becomes dispensable for chromosome segregation. We propose that despite the presence of centrosomes, the chromosome-derived Ran-GTP pathway has essential roles in functional spindle assembly in large, rapidly dividing vertebrate early embryos, similar to acentrosomal spindle assembly in oocytes.
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Affiliation(s)
- Ai Kiyomitsu
- Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa, 904-0495, Japan
| | - Toshiya Nishimura
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan
- Hokkaido University Fisheries Sciences, 3-1-1, Minato-cho, Hakodate, Hokkaido, 041-8611, Japan
| | - Shiang Jyi Hwang
- Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa, 904-0495, Japan
| | - Satoshi Ansai
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, 980-8577, Japan
- Laboratory of Genome Editing Breeding, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Masato T Kanemaki
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS), and Graduate Institute for Advanced Studies, SOKENDAI, Yata 1111, Mishima, Shizuoka, 411-8540, Japan
- Department of Biological Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Minoru Tanaka
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Tomomi Kiyomitsu
- Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa, 904-0495, Japan.
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4
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Tang H, Lu KJ, Zhang Y, Cheng YL, Tu SL, Friml J. Divergence of trafficking and polarization mechanisms for PIN auxin transporters during land plant evolution. PLANT COMMUNICATIONS 2024; 5:100669. [PMID: 37528584 PMCID: PMC10811345 DOI: 10.1016/j.xplc.2023.100669] [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: 01/06/2023] [Revised: 07/03/2023] [Accepted: 07/30/2023] [Indexed: 08/03/2023]
Abstract
The phytohormone auxin, and its directional transport through tissues, plays a fundamental role in the development of higher plants. This polar auxin transport predominantly relies on PIN-FORMED (PIN) auxin exporters. Hence, PIN polarization is crucial for development, but its evolution during the rise of morphological complexity in land plants remains unclear. Here, we performed a cross-species investigation by observing the trafficking and localization of endogenous and exogenous PINs in two bryophytes, Physcomitrium patens and Marchantia polymorpha, and in the flowering plant Arabidopsis thaliana. We confirmed that the GFP fusion did not compromise the auxin export function of all examined PINs by using a radioactive auxin export assay and by observing the phenotypic changes in transgenic bryophytes. Endogenous PINs polarize to filamentous apices, while exogenous Arabidopsis PINs distribute symmetrically on the membrane in both bryophytes. In the Arabidopsis root epidermis, bryophytic PINs have no defined polarity. Pharmacological interference revealed a strong cytoskeletal dependence of bryophytic but not Arabidopsis PIN polarization. The divergence of PIN polarization and trafficking is also observed within the bryophyte clade and between tissues of individual species. These results collectively reveal the divergence of PIN trafficking and polarity mechanisms throughout land plant evolution and the co-evolution of PIN sequence-based and cell-based polarity mechanisms.
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Affiliation(s)
- Han Tang
- Institute of Science and Technology Austria (ISTA), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Kuan-Ju Lu
- Graduate Institute of Biotechnology, National Chung Hsing University, No. 145, Xingda Rd., South Dist., Taichung 40227, Taiwan, R.O.C
| | - YuZhou Zhang
- College of Life Sciences, Northwest A&F University, Shaanxi, Yangling, China
| | - You-Liang Cheng
- Institute of Plant and Microbial Biology, Academia Sinica, 128 Sec. 2, Academia Rd, Nankang, Taipei 11529, Taiwan, R.O.C
| | - Shih-Long Tu
- Institute of Plant and Microbial Biology, Academia Sinica, 128 Sec. 2, Academia Rd, Nankang, Taipei 11529, Taiwan, R.O.C
| | - Jiří Friml
- Institute of Science and Technology Austria (ISTA), Am Campus 1, 3400 Klosterneuburg, Austria.
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Yoshida MW, Oguri N, Goshima G. Physcomitrium patens SUN2 Mediates MTOC Association with the Nuclear Envelope and Facilitates Chromosome Alignment during Spindle Assembly. PLANT & CELL PHYSIOLOGY 2023; 64:1106-1117. [PMID: 37421143 DOI: 10.1093/pcp/pcad074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/19/2023] [Accepted: 07/07/2023] [Indexed: 07/09/2023]
Abstract
Plant cells lack centrosomes and instead utilize acentrosomal microtubule organizing centers (MTOCs) to rapidly increase the number of microtubules at the onset of spindle assembly. Although several proteins required for MTOC formation have been identified, how the MTOC is positioned at the right place is not known. Here, we show that the inner nuclear membrane protein SUN2 is required for MTOC association with the nuclear envelope (NE) during mitotic prophase in the moss Physcomitrium patens. In actively dividing protonemal cells, microtubules accumulate around the NE during prophase. In particular, regional MTOC is formed at the apical surface of the nucleus. However, microtubule accumulation around the NE was impaired and apical MTOCs were mislocalized in sun2 knockout cells. Upon NE breakdown, the mitotic spindle was assembled with mislocalized MTOCs. However, completion of chromosome alignment in the spindle was delayed; in severe cases, the chromosome was transiently detached from the spindle body. SUN2 tended to localize to the apical surface of the nucleus during prophase in a microtubule-dependent manner. Based on these results, we propose that SUN2 facilitates the attachment of microtubules to chromosomes during spindle assembly by localizing microtubules to the NE. MTOC mispositioning was also observed during the first division of the gametophore tissue. Thus, this study suggests that microtubule-nucleus linking, a well-known function of SUN in animals and yeast, is conserved in plants.
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Affiliation(s)
- Mari W Yoshida
- Department of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
| | - Noiri Oguri
- Department of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
| | - Gohta Goshima
- Department of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, 429-63 Sugashima-cho, Toba, 517-0004 Japan
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6
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Causier B, McKay M, Hopes T, Lloyd J, Wang D, Harrison CJ, Davies B. The TOPLESS corepressor regulates developmental switches in the bryophyte Physcomitrium patens that were critical for plant terrestrialisation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1331-1344. [PMID: 37243383 PMCID: PMC10953049 DOI: 10.1111/tpj.16322] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/27/2023] [Accepted: 05/23/2023] [Indexed: 05/28/2023]
Abstract
The plant-specific TOPLESS (TPL) family of transcriptional corepressors is integral to multiple angiosperm developmental processes. Despite this, we know little about TPL function in other plants. To address this gap, we investigated the roles TPL plays in the bryophyte Physcomitrium patens, which diverged from angiosperms approximately 0.5 billion years ago. Although complete loss of PpTPL function is lethal, transgenic lines with reduced PpTPL activity revealed that PpTPLs are essential for two fundamental developmental switches in this plant: the transitions from basal photosynthetic filaments (chloronemata) to specialised foraging filaments (caulonemata) and from two-dimensional (2D) to three-dimensional (3D) growth. Using a transcriptomics approach, we integrated PpTPL into the regulatory network governing 3D growth and we propose that PpTPLs represent another important class of regulators that are essential for the 2D-to-3D developmental switch. Transcriptomics also revealed a previously unknown role for PpTPL in the regulation of flavonoids. Intriguingly, 3D growth and the formation of caulonemata were crucial innovations that facilitated the colonisation of land by plants, a major transformative event in the history of life on Earth. We conclude that TPL, which existed before the land plants, was co-opted into new developmental pathways, enabling phytoterrestrialisation and the evolution of land plants.
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Affiliation(s)
- Barry Causier
- Centre for Plant Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
| | - Mary McKay
- Centre for Plant Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
| | - Tayah Hopes
- Centre for Plant Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
- School of Molecular and Cellular Biology, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
| | - James Lloyd
- Centre for Plant Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Molecular SciencesThe University of Western AustraliaPerthWA6009Australia
| | - Dapeng Wang
- LeedsOmicsUniversity of LeedsLeedsLS2 9JTUK
- National Heart and Lung Institute, Imperial College LondonLondonSW3 6LYUK
| | - C. Jill Harrison
- School of Biological SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
| | - Brendan Davies
- Centre for Plant Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
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7
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Yoshida MW, Hakozaki M, Goshima G. Armadillo repeat-containing kinesin represents the versatile plus-end-directed transporter in Physcomitrella. NATURE PLANTS 2023; 9:733-748. [PMID: 37142749 DOI: 10.1038/s41477-023-01397-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 03/21/2023] [Indexed: 05/06/2023]
Abstract
Kinesin-1, also known as conventional kinesin, is widely used for microtubule plus-end-directed (anterograde) transport of various cargos in animal cells. However, a motor functionally equivalent to the conventional kinesin has not been identified in plants, which lack the kinesin-1 genes. Here we show that plant-specific armadillo repeat-containing kinesin (ARK) is the long sought-after versatile anterograde transporter in plants. In ARK mutants of the moss Physcomitrium patens, the anterograde motility of nuclei, chloroplasts, mitochondria and secretory vesicles was suppressed. Ectopic expression of non-motile or tail-deleted ARK did not restore organelle distribution. Another prominent macroscopic phenotype of ARK mutants was the suppression of cell tip growth. We showed that this defect was attributed to the mislocalization of actin regulators, including RopGEFs; expression and forced apical localization of RopGEF3 partially rescued the growth phenotype of the ARK mutant. The mutant phenotypes were partially rescued by ARK homologues in Arabidopsis thaliana, suggesting the conservation of ARK functions in plants.
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Affiliation(s)
- Mari W Yoshida
- Department of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Maya Hakozaki
- Department of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Gohta Goshima
- Department of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Toba, Japan.
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8
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Bellinger MA, Uyehara AN, Allsman L, Martinez P, McCarthy MC, Rasmussen CG. Cortical microtubules contribute to division plane positioning during telophase in maize. THE PLANT CELL 2023; 35:1496-1512. [PMID: 36753568 PMCID: PMC10118269 DOI: 10.1093/plcell/koad033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Cell divisions are accurately positioned to generate cells of the correct size and shape. In plant cells, the new cell wall is built in the middle of the cell by vesicles trafficked along an antiparallel microtubule and a microfilament array called the phragmoplast. The phragmoplast expands toward a specific location at the cell cortex called the division site, but how it accurately reaches the division site is unclear. We observed microtubule arrays that accumulate at the cell cortex during the telophase transition in maize (Zea mays) leaf epidermal cells. Before the phragmoplast reaches the cell cortex, these cortical-telophase microtubules transiently interact with the division site. Increased microtubule plus end capture and pausing occur when microtubules contact the division site-localized protein TANGLED1 or other closely associated proteins. Microtubule capture and pausing align the cortical microtubules perpendicular to the division site during telophase. Once the phragmoplast reaches the cell cortex, cortical-telophase microtubules are incorporated into the phragmoplast primarily by parallel bundling. The addition of microtubules into the phragmoplast promotes fine-tuning of the positioning at the division site. Our hypothesis is that division site-localized proteins such as TANGLED1 organize cortical microtubules during telophase to mediate phragmoplast positioning at the final division plane.
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Affiliation(s)
- Marschal A Bellinger
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
| | - Aimee N Uyehara
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
| | - Lindy Allsman
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
| | - Pablo Martinez
- Biochemistry Graduate Group, University of California, Riverside, CA 92508, USA
| | | | - Carolyn G Rasmussen
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
- Biochemistry Graduate Group, University of California, Riverside, CA 92508, USA
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9
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Hsiao AS, Huang JY. Microtubule Regulation in Plants: From Morphological Development to Stress Adaptation. Biomolecules 2023; 13:biom13040627. [PMID: 37189374 DOI: 10.3390/biom13040627] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/09/2023] [Accepted: 03/25/2023] [Indexed: 04/03/2023] Open
Abstract
Microtubules (MTs) are essential elements of the eukaryotic cytoskeleton and are critical for various cell functions. During cell division, plant MTs form highly ordered structures, and cortical MTs guide the cell wall cellulose patterns and thus control cell size and shape. Both are important for morphological development and for adjusting plant growth and plasticity under environmental challenges for stress adaptation. Various MT regulators control the dynamics and organization of MTs in diverse cellular processes and response to developmental and environmental cues. This article summarizes the recent progress in plant MT studies from morphological development to stress responses, discusses the latest techniques applied, and encourages more research into plant MT regulation.
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10
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Ta KN, Yoshida MW, Tezuka T, Shimizu-Sato S, Nosaka-Takahashi M, Toyoda A, Suzuki T, Goshima G, Sato Y. Control of Plant Cell Growth and Proliferation by MO25A, a Conserved Major Component of the Mammalian Sterile 20-Like Kinase Pathway. PLANT & CELL PHYSIOLOGY 2023; 64:336-351. [PMID: 36639938 PMCID: PMC10016325 DOI: 10.1093/pcp/pcad005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 01/07/2023] [Accepted: 01/12/2023] [Indexed: 05/22/2023]
Abstract
The precise control of cell growth and proliferation underpins the development of plants and animals. These factors affect the development and size of organs and the body. In plants, the growth and proliferation of cells are regulated by environmental stimuli and intrinsic signaling, allowing different cell types to have specific growth and proliferation characteristics. An increasing number of factors that control cell division and growth have been identified. However, the mechanisms underlying cell type-specific cell growth and proliferation characteristics in the normal developmental context are poorly understood. Here, we analyzed the rice mutant osmo25a1, which is defective in the progression of embryogenesis. The osmo25a1 mutant embryo developed incomplete embryonic organs, such as the shoot and root apical meristems. It showed a delayed progression of embryogenesis, associated with the reduced mitotic activity. The causal gene of this mutation encodes a member of the Mouse protein-25A (MO25A) family of proteins that have pivotal functions in a signaling pathway that governs cell proliferation and polarity in animals, yeasts and filamentous fungi. To elucidate the function of plant MO25A at the cellular level, we performed a functional analysis of MO25A in the moss Physcomitrium patens. Physcomitrium patens MO25A was uniformly distributed in the cytoplasm and functioned in cell tip growth and the initiation of cell division in stem cells. Overall, we demonstrated that MO25A proteins are conserved factors that control cell proliferation and growth.
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Affiliation(s)
- Kim Nhung Ta
- Department of Genome and Evolutionary Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
| | - Mari W Yoshida
- Department of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
| | - Takumi Tezuka
- Department of Genetics, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
| | - Sae Shimizu-Sato
- Department of Genome and Evolutionary Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
| | - Misuzu Nosaka-Takahashi
- Department of Genome and Evolutionary Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
- Department of Genetics, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
| | - Atsushi Toyoda
- Department of Genome and Evolutionary Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
| | - Takamasa Suzuki
- College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi, 487-8501 Japan
| | - Gohta Goshima
- Department of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, 429-63 Sugashima, Toba, 517-0004 Japan
| | - Yutaka Sato
- Department of Genome and Evolutionary Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
- Department of Genetics, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), 1111 Yata, Mishima, Shizuoka, 411-8540 Japan
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11
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Yoshida MW, Kozgunova E. Microfluidic Device for High-Resolution Cytoskeleton Imaging and Washout Assays in Physcomitrium (Physcomitrella) patens. Methods Mol Biol 2023; 2604:143-158. [PMID: 36773231 DOI: 10.1007/978-1-0716-2867-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Visualizing cytoskeleton dynamics at high spatiotemporal resolution provides valuable insights into the way the dynamics change as well as its interactions with multiple proteins in order to maintain cellular function. Oblique illumination fluorescent microscopy is a popular technique to image cellular events localized near the plasma membrane. In this chapter, we provide detailed protocols for high-resolution cytoskeleton imaging using protonema and gametophore cells of the moss Physcomitrella (Physcomitrium patens) in the microfluidic device. These include preparation of the polydimethylsiloxane (PDMS) device, culture of moss cells, and both short- and long-term oblique illumination fluorescent microscopy. We also describe how to introduce to, and wash out from, the device chemical compounds, such as microtubule-disrupting drugs, during live-cell imaging.
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Affiliation(s)
- Mari W Yoshida
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi, Japan
| | - Elena Kozgunova
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi, Japan. .,Institute for Advanced Research, Nagoya University, Nagoya, Japan.
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12
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Mills AM, Morris VH, Rasmussen CG. The localization of PHRAGMOPLAST ORIENTING KINESIN1 at the division site depends on the microtubule-binding proteins TANGLED1 and AUXIN-INDUCED IN ROOT CULTURES9 in Arabidopsis. THE PLANT CELL 2022; 34:4583-4599. [PMID: 36005863 PMCID: PMC9614452 DOI: 10.1093/plcell/koac266] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/08/2022] [Indexed: 05/04/2023]
Abstract
Proper plant growth and development require spatial coordination of cell divisions. Two unrelated microtubule-binding proteins, TANGLED1 (TAN1) and AUXIN-INDUCED IN ROOT CULTURES9 (AIR9), are together required for normal growth and division plane orientation in Arabidopsis (Arabidopsis thaliana). The tan1 air9 double mutant has synthetic growth and division plane orientation defects, while single mutants lack obvious defects. Here we show that the division site-localized protein, PHRAGMOPLAST ORIENTING KINESIN1 (POK1), was aberrantly lost from the division site during metaphase and telophase in the tan1 air9 mutant. Since TAN1 and POK1 interact via the first 132 amino acids of TAN1 (TAN11-132), we assessed the localization and function of TAN11-132 in the tan1 air9 double mutant. TAN11-132 rescued tan1 air9 mutant phenotypes and localized to the division site during telophase. However, replacing six amino-acid residues within TAN11-132, which disrupted the POK1-TAN1 interaction in the yeast-two-hybrid system, caused loss of both rescue and division site localization of TAN11-132 in the tan1 air9 mutant. Full-length TAN1 with the same alanine substitutions had defects in phragmoplast guidance and reduced TAN1 and POK1 localization at the division site but rescued most tan1 air9 mutant phenotypes. Together, these data suggest that TAN1 and AIR9 are required for POK1 localization, and yet unknown proteins may stabilize TAN1-POK1 interactions.
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Affiliation(s)
- Alison M Mills
- Graduate Group in Biochemistry and Molecular Biology, University of California, Riverside, California, USA
| | - Victoria H Morris
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside, California, USA
| | - Carolyn G Rasmussen
- Graduate Group in Biochemistry and Molecular Biology, University of California, Riverside, California, USA
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside, California, USA
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13
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The augmin complex architecture reveals structural insights into microtubule branching. Nat Commun 2022; 13:5635. [PMID: 36163468 PMCID: PMC9512787 DOI: 10.1038/s41467-022-33228-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/05/2022] [Indexed: 11/24/2022] Open
Abstract
In mitosis, the augmin complex binds to spindle microtubules to recruit the γ-tubulin ring complex (γ-TuRC), the principal microtubule nucleator, for the formation of branched microtubules. Our understanding of augmin-mediated microtubule branching is hampered by the lack of structural information on the augmin complex. Here, we elucidate the molecular architecture and conformational plasticity of the augmin complex using an integrative structural biology approach. The elongated structure of the augmin complex is characterised by extensive coiled-coil segments and comprises two structural elements with distinct but complementary functions in γ-TuRC and microtubule binding, linked by a flexible hinge. The augmin complex is recruited to microtubules via a composite microtubule binding site comprising a positively charged unordered extension and two calponin homology domains. Our study provides the structural basis for augmin function in branched microtubule formation, decisively fostering our understanding of spindle formation in mitosis. The formation of branched microtubule networks in mitotic spindles depends on the augmin complex. Zupa, Würtz et al. elucidate the molecular architecture and conformational plasticity of the augmin complex using integrative structural biology, providing structural insights into microtubule branching.
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14
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Diurnal control of intracellular distributions of PAS-Histidine kinase 1 and its interactions with partner proteins in the moss Physcomitrium patens. Biochem Biophys Res Commun 2022; 616:1-7. [DOI: 10.1016/j.bbrc.2022.05.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 11/20/2022]
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15
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Abstract
In contrast to well-studied fungal and animal cells, plant cells assemble bipolar spindles that exhibit a great deal of plasticity in the absence of structurally defined microtubule-organizing centers like the centrosome. While plants employ some evolutionarily conserved proteins to regulate spindle morphogenesis and remodeling, many essential spindle assembly factors found in vertebrates are either missing or not required for producing the plant bipolar microtubule array. Plants also produce proteins distantly related to their fungal and animal counterparts to regulate critical events such as the spindle assembly checkpoint. Plant spindle assembly initiates with microtubule nucleation on the nuclear envelope followed by bipolarization into the prophase spindle. After nuclear envelope breakdown, kinetochore fibers are assembled and unified into the spindle apparatus with convergent poles. Of note, compared to fungal and animal systems, relatively little is known about how plant cells remodel the spindle microtubule array during anaphase. Uncovering mitotic functions of novel proteins for spindle assembly in plants will illuminate both common and divergent mechanisms employed by different eukaryotic organisms to segregate genetic materials.
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Affiliation(s)
- Bo Liu
- Department of Plant Biology, University of California, Davis, California, USA; ,
| | - Yuh-Ru Julie Lee
- Department of Plant Biology, University of California, Davis, California, USA; ,
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16
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Spindle motility skews division site determination during asymmetric cell division in Physcomitrella. Nat Commun 2022; 13:2488. [PMID: 35513464 PMCID: PMC9072379 DOI: 10.1038/s41467-022-30239-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 04/21/2022] [Indexed: 01/09/2023] Open
Abstract
Asymmetric cell division (ACD) underlies the development of multicellular organisms. In animal ACD, the cell division site is determined by active spindle-positioning mechanisms. In contrast, it is considered that the division site in plants is determined prior to mitosis by the microtubule-actin belt known as the preprophase band (PPB) and that the localization of the mitotic spindle is typically static and does not govern the division plane. However, in some plant species, ACD occurs in the absence of PPB. Here, we isolate a hypomorphic mutant of the conserved microtubule-associated protein TPX2 in the moss Physcomitrium patens (Physcomitrella) and observe spindle motility during PPB-independent cell division. This defect compromises the position of the division site and produces inverted daughter cell sizes in the first ACD of gametophore (leafy shoot) development. The phenotype is rescued by restoring endogenous TPX2 function and, unexpectedly, by depolymerizing actin filaments. Thus, we identify an active spindle-positioning mechanism that, reminiscent of acentrosomal ACD in animals, involves microtubules and actin filaments, and sets the division site in plants.
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17
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Weiss JD, McVey SL, Stinebaugh SE, Sullivan CF, Dawe RK, Nannas NJ. Frequent Spindle Assembly Errors Require Structural Rearrangement to Complete Meiosis in Zea mays. Int J Mol Sci 2022; 23:ijms23084293. [PMID: 35457112 PMCID: PMC9031645 DOI: 10.3390/ijms23084293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/01/2022] [Accepted: 04/05/2022] [Indexed: 12/04/2022] Open
Abstract
The success of an organism is contingent upon its ability to faithfully pass on its genetic material. In the meiosis of many species, the process of chromosome segregation requires that bipolar spindles be formed without the aid of dedicated microtubule organizing centers, such as centrosomes. Here, we describe detailed analyses of acentrosomal spindle assembly and disassembly in time-lapse images, from live meiotic cells of Zea mays. Microtubules organized on the nuclear envelope with a perinuclear ring structure until nuclear envelope breakdown, at which point microtubules began bundling into a bipolar form. However, the process and timing of spindle assembly was highly variable, with frequent assembly errors in both meiosis I and II. Approximately 61% of cells formed incorrect spindle morphologies, with the most prevalent being tripolar spindles. The erroneous spindles were actively rearranged to bipolar through a coalescence of poles before proceeding to anaphase. Spindle disassembly occurred as a two-state process with a slow depolymerization, followed by a quick collapse. The results demonstrate that maize meiosis I and II spindle assembly is remarkably fluid in the early assembly stages, but otherwise proceeds through a predictable series of events.
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Affiliation(s)
- Jodi D. Weiss
- Department of Biology, Hamilton College, Clinton, NY 13323, USA; (J.D.W.); (S.L.M.); (S.E.S.); (C.F.S.)
| | - Shelby L. McVey
- Department of Biology, Hamilton College, Clinton, NY 13323, USA; (J.D.W.); (S.L.M.); (S.E.S.); (C.F.S.)
| | - Sarah E. Stinebaugh
- Department of Biology, Hamilton College, Clinton, NY 13323, USA; (J.D.W.); (S.L.M.); (S.E.S.); (C.F.S.)
| | - Caroline F. Sullivan
- Department of Biology, Hamilton College, Clinton, NY 13323, USA; (J.D.W.); (S.L.M.); (S.E.S.); (C.F.S.)
| | - R. Kelly Dawe
- Department of Genetics, University of Georgia, Athens, GA 30602, USA;
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Natalie J. Nannas
- Department of Biology, Hamilton College, Clinton, NY 13323, USA; (J.D.W.); (S.L.M.); (S.E.S.); (C.F.S.)
- Correspondence:
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18
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Shen A, Liu L, Huang Y, Shen Z, Wu M, Chen X, Wu X, Lin X, Chen Y, Li L, Cheng Y, Chu J, Sferra TJ, Wei L, Zhuang Q, Peng J. Down-Regulating HAUS6 Suppresses Cell Proliferation by Activating the p53/p21 Pathway in Colorectal Cancer. Front Cell Dev Biol 2022; 9:772077. [PMID: 35096810 PMCID: PMC8790508 DOI: 10.3389/fcell.2021.772077] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/24/2021] [Indexed: 12/15/2022] Open
Abstract
Background: HAUS6 participates in microtubule-dependent microtubule amplification, but its role in malignancies including colorectal cancer (CRC) has not been explored. We therefore assessed the potential oncogenic activities of HAUS6 in CRC. Results: HAUS6 mRNA and protein expression is higher in CRC tissues, and high HAUS6 expression is correlated with shorter overall survival in CRC patients. HAUS6 knockdown in CRC cell lines suppressed cell growth in vitro and in vivo by inhibiting cell viability, survival and arresting cell cycle progression at G0/G1, while HAUS6 over-expression increased cell viability. We showed that these effects are dependent on activation of the p53/p21 signalling pathway by reducing p53 and p21 degradation. Moreover, combination of HAUS6 knockdown and 5-FU treatment further enhanced the suppression of cell proliferation of CRC cells by increasing activation of the p53/p21 pathway. Conclusion: Our study highlights a potential oncogenic role for HAUS6 in CRC. Targeting HAUS6 may be a promising novel prognostic marker and chemotherapeutic target for treating CRC patients.
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Affiliation(s)
- Aling Shen
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Liya Liu
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Yue Huang
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Zhiqing Shen
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Meizhu Wu
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Xiaoping Chen
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Xiangyan Wu
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Xiaoying Lin
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Youqin Chen
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China.,Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, Cleveland, OH, United States
| | - Li Li
- Department of Health Management, Fujian Provincial Hospital, Fuzhou, China
| | - Ying Cheng
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Jianfeng Chu
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Thomas J Sferra
- Department of Health Management, Fujian Provincial Hospital, Fuzhou, China
| | - Lihui Wei
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Qunchuan Zhuang
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Jun Peng
- Academy of Integrative Medicine, Fuzhou, China.,Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, China
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19
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Gu Y, Rasmussen CG. Cell biology of primary cell wall synthesis in plants. THE PLANT CELL 2022; 34:103-128. [PMID: 34613413 PMCID: PMC8774047 DOI: 10.1093/plcell/koab249] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/01/2021] [Indexed: 05/07/2023]
Abstract
Building a complex structure such as the cell wall, with many individual parts that need to be assembled correctly from distinct sources within the cell, is a well-orchestrated process. Additional complexity is required to mediate dynamic responses to environmental and developmental cues. Enzymes, sugars, and other cell wall components are constantly and actively transported to and from the plasma membrane during diffuse growth. Cell wall components are transported in vesicles on cytoskeletal tracks composed of microtubules and actin filaments. Many of these components, and additional proteins, vesicles, and lipids are trafficked to and from the cell plate during cytokinesis. In this review, we first discuss how the cytoskeleton is initially organized to add new cell wall material or to build a new cell wall, focusing on similarities during these processes. Next, we discuss how polysaccharides and enzymes that build the cell wall are trafficked to the correct location by motor proteins and through other interactions with the cytoskeleton. Finally, we discuss some of the special features of newly formed cell walls generated during cytokinesis.
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Affiliation(s)
- Ying Gu
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Carolyn G Rasmussen
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, University of California, Riverside, California 92521
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20
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Gomes Pereira S, Sousa AL, Nabais C, Paixão T, Holmes AJ, Schorb M, Goshima G, Tranfield EM, Becker JD, Bettencourt-Dias M. The 3D architecture and molecular foundations of de novo centriole assembly via bicentrioles. Curr Biol 2021; 31:4340-4353.e7. [PMID: 34433076 DOI: 10.1101/2020.12.21.423647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 05/19/2023]
Abstract
Centrioles are structurally conserved organelles, composing both centrosomes and cilia. In animal cycling cells, centrioles often form through a highly characterized process termed canonical duplication. However, a large diversity of eukaryotes assemble centrioles de novo through uncharacterized pathways. This unexplored diversity is key to understanding centriole assembly mechanisms and how they evolved to assist specific cellular functions. Here, we show that, during spermatogenesis of the bryophyte Physcomitrium patens, centrioles are born as a co-axially oriented centriole pair united by a cartwheel. Interestingly, we observe that these centrioles are twisted in opposite orientations. Microtubules emanate from the bicentrioles, which localize to the spindle poles during cell division. After their separation, the two resulting sister centrioles mature asymmetrically, elongating specific microtubule triplets and a naked cartwheel. Subsequently, two motile cilia are assembled that appear to alternate between different motility patterns. We further show that centriolar components SAS6, Bld10, and POC1, which are conserved across eukaryotes, are expressed during spermatogenesis and required for this de novo biogenesis pathway. Our work supports a scenario where centriole biogenesis, while driven by conserved molecular modules, is more diverse than previously thought.
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Affiliation(s)
- Sónia Gomes Pereira
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
| | - Ana Laura Sousa
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Catarina Nabais
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Tiago Paixão
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Alexander J Holmes
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Martin Schorb
- Electron Microscopy Core Facility, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Gohta Goshima
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, 429-63, Toba 517-0004, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Erin M Tranfield
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal.
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21
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Gomes Pereira S, Sousa AL, Nabais C, Paixão T, Holmes AJ, Schorb M, Goshima G, Tranfield EM, Becker JD, Bettencourt-Dias M. The 3D architecture and molecular foundations of de novo centriole assembly via bicentrioles. Curr Biol 2021; 31:4340-4353.e7. [PMID: 34433076 DOI: 10.1016/j.cub.2021.07.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 12/18/2022]
Abstract
Centrioles are structurally conserved organelles, composing both centrosomes and cilia. In animal cycling cells, centrioles often form through a highly characterized process termed canonical duplication. However, a large diversity of eukaryotes assemble centrioles de novo through uncharacterized pathways. This unexplored diversity is key to understanding centriole assembly mechanisms and how they evolved to assist specific cellular functions. Here, we show that, during spermatogenesis of the bryophyte Physcomitrium patens, centrioles are born as a co-axially oriented centriole pair united by a cartwheel. Interestingly, we observe that these centrioles are twisted in opposite orientations. Microtubules emanate from the bicentrioles, which localize to the spindle poles during cell division. After their separation, the two resulting sister centrioles mature asymmetrically, elongating specific microtubule triplets and a naked cartwheel. Subsequently, two motile cilia are assembled that appear to alternate between different motility patterns. We further show that centriolar components SAS6, Bld10, and POC1, which are conserved across eukaryotes, are expressed during spermatogenesis and required for this de novo biogenesis pathway. Our work supports a scenario where centriole biogenesis, while driven by conserved molecular modules, is more diverse than previously thought.
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Affiliation(s)
- Sónia Gomes Pereira
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
| | - Ana Laura Sousa
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Catarina Nabais
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Tiago Paixão
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Alexander J Holmes
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Martin Schorb
- Electron Microscopy Core Facility, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Gohta Goshima
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, 429-63, Toba 517-0004, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Erin M Tranfield
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal.
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22
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Anami S, Yamashino T, Suzuki R, Nakai K, Sato K, Wu B, Ryo M, Sugita M, Aoki S. Red light-regulated interaction of Per-Arnt-Sim histidine kinases with partner histidine-containing phosphotransfer proteins in Physcomitrium patens. Genes Cells 2021; 26:698-713. [PMID: 34086383 DOI: 10.1111/gtc.12878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 05/24/2021] [Accepted: 06/02/2021] [Indexed: 11/29/2022]
Abstract
Multi-step phosphorelay (MSP) is a broadly distributed signaling system in organisms. In MSP, histidine kinases (HKs) receive various environmental signals and transmit them by autophosphorylation followed by phosphotransfer to partner histidine-containing phosphotransfer proteins (HPts). Previously, we reported that Per-Arnt-Sim (PAS) domain-containing HK1 (PHK1) and PHK2 of the moss Physcomitrium (Physcomitrella) patens repressed red light-induced protonema branching, a critical step in the moss life cycle. In plants, PHK homolog-encoding genes are conserved only in early-diverging lineages such as bryophytes and lycophytes. PHKs-mediated signaling machineries attract attention especially from an evolutionary viewpoint, but they remain uninvestigated. Here, we studied the P. patens PHKs focusing on their subcellular patterns of localization and interaction with HPts. Yeast two-hybrid analysis, a localization assay with a green fluorescent protein, and a bimolecular fluorescence complementation analysis together showed that PHKs are localized and interact with partner HPts mostly in the nucleus, as unprecedented features for plant HKs. Additionally, red light triggered the interactions between PHKs and HPts in the cytoplasm, and light co-repressed the expression of PHK1 and PHK2 as well as genes encoding their partner HPts. Our results emphasize the uniqueness of PHKs-mediated signaling machineries, and functional implications of this uniqueness are discussed.
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Affiliation(s)
- Shu Anami
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | | | - Ryo Suzuki
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Kota Nakai
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Kensuke Sato
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Bowen Wu
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Masashi Ryo
- Graduate School of Information Science, Nagoya University, Nagoya, Japan
| | - Mamoru Sugita
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Setsuyuki Aoki
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
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23
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Overdijk EJR, Putker V, Smits J, Tang H, Bouwmeester K, Govers F, Ketelaar T. Phytophthora infestans RXLR effector AVR1 disturbs the growth of Physcomitrium patens without affecting Sec5 localization. PLoS One 2021; 16:e0249637. [PMID: 33831039 PMCID: PMC8031463 DOI: 10.1371/journal.pone.0249637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 03/22/2021] [Indexed: 11/19/2022] Open
Abstract
Plant pathogens often exploit a whole range of effectors to facilitate infection. The RXLR effector AVR1 produced by the oomycete plant pathogen Phytophthora infestans suppresses host defense by targeting Sec5. Sec5 is a subunit of the exocyst, a protein complex that is important for mediating polarized exocytosis during plant development and defense against pathogens. The mechanism by which AVR1 manipulates Sec5 functioning is unknown. In this study, we analyzed the effect of AVR1 on Sec5 localization and functioning in the moss Physcomitrium patens. P. patens has four Sec5 homologs. Two (PpSec5b and PpSec5d) were found to interact with AVR1 in yeast-two-hybrid assays while none of the four showed a positive interaction with AVR1ΔT, a truncated version of AVR1. In P. patens lines carrying β-estradiol inducible AVR1 or AVR1ΔT transgenes, expression of AVR1 or AVR1ΔT caused defects in the development of caulonemal protonema cells and abnormal morphology of chloronema cells. Similar phenotypes were observed in Sec5- or Sec6-silenced P. patens lines, suggesting that both AVR1 and AVR1ΔT affect exocyst functioning in P. patens. With respect to Sec5 localization we found no differences between β-estradiol-treated and untreated transgenic AVR1 lines. Sec5 localizes at the plasma membrane in growing caulonema cells, also during pathogen attack, and its subcellular localization is the same, with or without AVR1 in the vicinity.
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Affiliation(s)
- Elysa J. R. Overdijk
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
| | - Vera Putker
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Joep Smits
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Han Tang
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Klaas Bouwmeester
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
- Biosystematics Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Francine Govers
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
- * E-mail:
| | - Tijs Ketelaar
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
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24
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Orr RG, Foley SJ, Sherman C, Abreu I, Galotto G, Liu B, González-Guerrero M, Vidali L. Robust Survival-Based RNA Interference of Gene Families Using in Tandem Silencing of Adenine Phosphoribosyltransferase. PLANT PHYSIOLOGY 2020; 184:607-619. [PMID: 32764132 PMCID: PMC7536682 DOI: 10.1104/pp.20.00865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 07/15/2020] [Indexed: 05/07/2023]
Abstract
RNA interference (RNAi) enables flexible and dynamic interrogation of entire gene families or essential genes without the need for exogenous proteins, unlike CRISPR-Cas technology. Unfortunately, isolation of plants undergoing potent gene silencing requires laborious design, visual screening, and physical separation for downstream characterization. Here, we developed an adenine phosphoribosyltransferase (APT)-based RNAi technology (APTi) in Physcomitrella patens that improves upon the multiple limitations of current RNAi techniques. APTi exploits the prosurvival output of transiently silencing APT in the presence of 2-fluoroadenine, thereby establishing survival itself as a reporter of RNAi. To maximize the silencing efficacy of gene targets, we created vectors that facilitate insertion of any gene target sequence in tandem with the APT silencing motif. We tested the efficacy of APTi with two gene families, the actin-dependent motor, myosin XI (a,b), and the putative chitin receptor Lyk5 (a,b,c). The APTi approach resulted in a homogenous population of transient P. patens mutants specific for our gene targets with zero surviving background plants within 8 d. The observed mutants directly corresponded to a maximal 93% reduction of myosin XI protein and complete loss of chitin-induced calcium spiking in the Lyk5-RNAi background. The positive selection nature of APTi represents a fundamental improvement in RNAi technology and will contribute to the growing demand for technologies amenable to high-throughput phenotyping.
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Affiliation(s)
- Robert G Orr
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
| | - Stephen J Foley
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
| | - Catherine Sherman
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, Massachusetts 01605
| | - Isidro Abreu
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA), Universidad Politécnica de Madrid, Madrid 28223, Spain
| | - Giulia Galotto
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
| | - Boyuan Liu
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA), Universidad Politécnica de Madrid, Madrid 28223, Spain
| | - Luis Vidali
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609
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25
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Rho of Plants GTPases and Cytoskeletal Elements Control Nuclear Positioning and Asymmetric Cell Division during Physcomitrella patens Branching. Curr Biol 2020; 30:2860-2868.e3. [PMID: 32470363 DOI: 10.1016/j.cub.2020.05.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 04/06/2020] [Accepted: 05/06/2020] [Indexed: 02/02/2023]
Abstract
Branching morphogenesis is a widely used mechanism for development [1, 2]. In plants, it is initiated by the emergence of a new growth axis, which is of particular importance for plants to explore space and access resources [1]. Branches can emerge either from a single cell or from a group of cells [3-5]. In both cases, the mother cells that initiate branching must undergo dynamic morphological changes and/or adopt oriented asymmetric cell divisions (ACDs) to establish the new growth direction. However, the underlying mechanisms are not fully understood. Here, using the bryophyte moss Physcomitrella patens as a model, we show that side-branch formation in P. patens protonemata requires coordinated polarized cell expansion, directional nuclear migration, and orientated ACD. By combining pharmacological experiments, long-term time-lapse imaging, and genetic analyses, we demonstrate that Rho of plants (ROP) GTPases and actin are essential for cell polarization and local cell expansion (bulging). The growing bulge acts as a prerequisite signal to guide long-distance microtubule (MT)-dependent nuclear migration, which determines the asymmetric positioning of the division plane. MTs play an essential role in nuclear migration but are less involved in bulge formation. Hence, cell polarity and cytoskeletal elements act cooperatively to modulate cell morphology and nuclear positioning during branch initiation. We propose that polarity-triggered nuclear positioning and ACD comprise a fundamental mechanism for increasing multicellularity and tissue complexity during plant morphogenesis.
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26
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Rensing SA, Goffinet B, Meyberg R, Wu SZ, Bezanilla M. The Moss Physcomitrium ( Physcomitrella) patens: A Model Organism for Non-Seed Plants. THE PLANT CELL 2020; 32:1361-1376. [PMID: 32152187 PMCID: PMC7203925 DOI: 10.1105/tpc.19.00828] [Citation(s) in RCA: 149] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 02/17/2020] [Accepted: 03/05/2020] [Indexed: 05/06/2023]
Abstract
Since the discovery two decades ago that transgenes are efficiently integrated into the genome of Physcomitrella patens by homologous recombination, this moss has been a premier model system to study evolutionary developmental biology questions, stem cell reprogramming, and the biology of nonvascular plants. P patens was the first non-seed plant to have its genome sequenced. With this level of genomic information, together with increasing molecular genetic tools, a large number of reverse genetic studies have propelled the use of this model system. A number of technological advances have recently opened the door to forward genetics as well as extremely efficient and precise genome editing in P patens Additionally, careful phylogenetic studies with increased resolution have suggested that P patens emerged from within Physcomitrium Thus, rather than Physcomitrella patens, the species should be named Physcomitrium patens Here we review these advances and describe the areas where P patens has had the most impact on plant biology.
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Affiliation(s)
- Stefan A Rensing
- Faculty of Biology, Plant Cell Biology, Philipps University of Marburg, 35037 Marburg an der Lahn, Hesse, Germany
| | - Bernard Goffinet
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269
| | - Rabea Meyberg
- Faculty of Biology, Plant Cell Biology, Philipps University of Marburg, 35037 Marburg an der Lahn, Hesse, Germany
| | - Shu-Zon Wu
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755
| | - Magdalena Bezanilla
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755
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27
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Leong SY, Edzuka T, Goshima G, Yamada M. Kinesin-13 and Kinesin-8 Function during Cell Growth and Division in the Moss Physcomitrella patens. THE PLANT CELL 2020; 32:683-702. [PMID: 31919299 PMCID: PMC7054034 DOI: 10.1105/tpc.19.00521] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/25/2019] [Accepted: 01/07/2020] [Indexed: 05/03/2023]
Abstract
Kinesin-13 and Kinesin-8 are well-known microtubule (MT) depolymerases that regulate MT length and chromosome movement in animal mitosis. While much is unknown about plant Kinesin-8, Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) Kinesin-13 have been shown to depolymerize MTs in vitro. However, the mitotic function of both kinesins has yet to be determined in plants. Here, we generated complete null mutants of Kinesin-13 and Kinesin-8 in moss (Physcomitrella patens). Both kinesins were found to be nonessential for viability, but the Kinesin-13 knockout (KO) line had increased mitotic duration and reduced spindle length, whereas the Kinesin-8 KO line did not display obvious mitotic defects. Surprisingly, spindle MT poleward flux, which is mediated by Kinesin-13 in animals, was retained in the absence of Kinesin-13. MT depolymerase activity was not detectable for either kinesin in vitro, while MT catastrophe-inducing activity (Kinesin-13) or MT gliding activity (Kinesin-8) was observed. Interestingly, both KO lines showed waviness in their protonema filaments, which correlated with positional instability of the MT foci in their tip cells. Taken together, the results suggest that plant Kinesin-13 and Kinesin-8 have diverged in both mitotic function and molecular activity, acquiring roles in regulating MT foci positioning for directed tip growth.
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Affiliation(s)
- Shu Yao Leong
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Tomoya Edzuka
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Moé Yamada
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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28
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Alfaro-Aco R, Thawani A, Petry S. Biochemical reconstitution of branching microtubule nucleation. eLife 2020; 9:e49797. [PMID: 31933480 PMCID: PMC6959992 DOI: 10.7554/elife.49797] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 12/12/2019] [Indexed: 12/31/2022] Open
Abstract
Microtubules are nucleated from specific locations at precise times in the cell cycle. However, the factors that constitute these microtubule nucleation pathways and their mode of action still need to be identified. Using purified Xenopus laevis proteins we biochemically reconstitute branching microtubule nucleation, which is critical for chromosome segregation. We found that besides the microtubule nucleator gamma-tubulin ring complex (γ-TuRC), the branching effectors augmin and TPX2 are required to efficiently nucleate microtubules from pre-existing microtubules. TPX2 has the unexpected capacity to directly recruit γ-TuRC as well as augmin, which in turn targets more γ-TuRC along the microtubule lattice. TPX2 and augmin enable γ-TuRC-dependent microtubule nucleation at preferred branching angles of less than 90 degrees from regularly-spaced patches along microtubules. This work provides a blueprint for other microtubule nucleation pathways and helps explain how microtubules are generated in the spindle.
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Affiliation(s)
| | - Akanksha Thawani
- Department of Chemical and Biological EngineeringPrinceton UniversityPrincetonUnited States
| | - Sabine Petry
- Department of Molecular BiologyPrinceton UniversityPrincetonUnited States
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29
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Alfaro-Aco R, Thawani A, Petry S. Biochemical reconstitution of branching microtubule nucleation. eLife 2020. [PMID: 31933480 DOI: 10.1101/700047v1.full] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
Microtubules are nucleated from specific locations at precise times in the cell cycle. However, the factors that constitute these microtubule nucleation pathways and their mode of action still need to be identified. Using purified Xenopus laevis proteins we biochemically reconstitute branching microtubule nucleation, which is critical for chromosome segregation. We found that besides the microtubule nucleator gamma-tubulin ring complex (γ-TuRC), the branching effectors augmin and TPX2 are required to efficiently nucleate microtubules from pre-existing microtubules. TPX2 has the unexpected capacity to directly recruit γ-TuRC as well as augmin, which in turn targets more γ-TuRC along the microtubule lattice. TPX2 and augmin enable γ-TuRC-dependent microtubule nucleation at preferred branching angles of less than 90 degrees from regularly-spaced patches along microtubules. This work provides a blueprint for other microtubule nucleation pathways and helps explain how microtubules are generated in the spindle.
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Affiliation(s)
- Raymundo Alfaro-Aco
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Akanksha Thawani
- Department of Chemical and Biological Engineering, Princeton University, Princeton, United States
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, United States
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30
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The γ-tubulin complex protein GCP6 is crucial for spindle morphogenesis but not essential for microtubule reorganization in Arabidopsis. Proc Natl Acad Sci U S A 2019; 116:27115-27123. [PMID: 31818952 DOI: 10.1073/pnas.1912240116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
γ-Tubulin typically forms a ring-shaped complex with 5 related γ-tubulin complex proteins (GCP2 to GCP6), and this γ-tubulin ring complex (γTuRC) serves as a template for microtubule (MT) nucleation in plants and animals. While the γTuRC takes part in MT nucleation in most eukaryotes, in fungi such events take place robustly with just the γ-tubulin small complex (γTuSC) assembled by γ-tubulin plus GCP2 and GCP3. To explore whether the γTuRC is the sole functional γ-tubulin complex in plants, we generated 2 mutants of the GCP6 gene encoding the largest subunit of the γTuRC in Arabidopsis thaliana Both mutants showed similar phenotypes of dwarfed vegetative growth and reduced fertility. The gcp6 mutant assembled the γTuSC, while the wild-type cells had GCP6 join other GCPs to produce the γTuRC. Although the gcp6 cells had greatly diminished γ-tubulin localization on spindle MTs, the protein was still detected there. The gcp6 cells formed spindles that lacked MT convergence and discernable poles; however, they managed to cope with the challenge of MT disorganization and were able to complete mitosis and cytokinesis. Our results reveal that the γTuRC is not the only functional form of the γ-tubulin complex for MT nucleation in plant cells, and that γ-tubulin-dependent, but γTuRC-independent, mechanisms meet the basal need of MT nucleation. Moreover, we show that the γTuRC function is more critical for the assembly of spindle MT array than for the phragmoplast. Thus, our findings provide insight into acentrosomal MT nucleation and organization.
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31
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Wasteneys GO. Plant Cell Biology: Shifting CORDs to Fine-Tune Phragmoplast Microtubule Turnover. Curr Biol 2019; 29:R1235-R1238. [PMID: 31794755 DOI: 10.1016/j.cub.2019.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A new study provides insight into microtubule turnover during plant cell division. Using clever molecular-genetic and imaging strategies, the authors demonstrate that the recently discovered CORD4 and 5 proteins associate with phragmoplast microtubules and control recruitment and activity of the microtubule-severing protein katanin.
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32
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Buschmann H, Müller S. Update on plant cytokinesis: rule and divide. CURRENT OPINION IN PLANT BIOLOGY 2019; 52:97-105. [PMID: 31542698 DOI: 10.1016/j.pbi.2019.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/28/2019] [Accepted: 07/09/2019] [Indexed: 06/10/2023]
Abstract
Many decisions made during plant development depend on the placement of the cytokinetic wall. Cytokinesis involves the biogenesis of the cell plate that progresses centrifugally and until the fusion of the cell plate with the parental cell wall. The phragmoplast facilitates the growth of the cell plate and directs it's insertion at the cell cortex by a mechanism known as phragmoplast guidance. Communication between the phragmoplast and its destination, the cortical division zone, however, is not well understood. The preprophase band predicts the site of cell plate fusion, seemingly controlling the site of the cortical division zone establishment, but recent results suggest the role of this cytoskeletal array to be rather subtle. This is indirectly supported by certain types of phragmoplast-driven cell division in mosses and algae, which lack preprophase bands. In this review article, we summarize recent insight concerning phragmoplast expansion and guidance.
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Affiliation(s)
| | - Sabine Müller
- Center for Plant Molecular Biology, University of Tübingen, Germany.
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33
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Kozgunova E, Goshima G. A versatile microfluidic device for highly inclined thin illumination microscopy in the moss Physcomitrella patens. Sci Rep 2019; 9:15182. [PMID: 31645620 PMCID: PMC6811556 DOI: 10.1038/s41598-019-51624-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/03/2019] [Indexed: 12/26/2022] Open
Abstract
High-resolution microscopy is a valuable tool for studying cellular processes, such as signalling, membrane trafficking, or cytoskeleton remodelling. Several techniques of inclined illumination microscopy allow imaging at a near single molecular level; however, the application of these methods to plant cells is limited, owing to thick cell walls as well as the necessity to excise a part of the tissue for sample preparation. In this study, we utilised a simple, easy-to-use microfluidic device for highly inclined and laminated optical sheet (HILO) microscopy using a model plant Physcomitrella patens. We demonstrated that the shallow microfluidic device can be used for long-term culture of living cells and enables high-resolution HILO imaging of microtubules without perturbing their dynamics. In addition, our microdevice allows the supply and robust washout of compounds during HILO microscopy imaging, for example, to perform a microtubule regrowth assay. Furthermore, we tested long-term (48 h) HILO imaging using a microdevice and visualised the developmental changes in the microtubule dynamics during tissue regeneration. These novel applications of the microfluidic device provide a valuable resource for studying molecular dynamics in living plant cells.
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Affiliation(s)
- Elena Kozgunova
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
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34
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Lee YRJ, Liu B. Microtubule nucleation for the assembly of acentrosomal microtubule arrays in plant cells. THE NEW PHYTOLOGIST 2019; 222:1705-1718. [PMID: 30681146 DOI: 10.1111/nph.15705] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/07/2019] [Indexed: 05/15/2023]
Abstract
Contents Summary I. Introduction II. MT arrays in plant cells III. γ-Tubulin and MT nucleation IV. MT nucleation sites or flexible MTOCs in plant cells V. MT-dependent MT nucleation VI. Generating new MTs for spindle assembly VII. Generation of MTs for phragmoplast expansion during cytokinesis VIII. MT generation for the cortical MT array IX. MT nucleation: looking forward Acknowledgements References SUMMARY: Cytoskeletal microtubules (MTs) have a multitude of functions including intracellular distribution of molecules and organelles, cell morphogenesis, as well as segregation of the genetic material and separation of the cytoplasm during cell division among eukaryotic organisms. In response to internal and external cues, eukaryotic cells remodel their MT network in a regulated manner in order to assemble physiologically important arrays for cell growth, cell proliferation, or for cells to cope with biotic or abiotic stresses. Nucleation of new MTs is a critical step for MT remodeling. Although many key factors contributing to MT nucleation and organization are well conserved in different kingdoms, the centrosome, representing the most prominent microtubule organizing centers (MTOCs), disappeared during plant evolution as angiosperms lack the structure. Instead, flexible MTOCs may emerge on the plasma membrane, the nuclear envelope, and even organelles depending on types of cells and organisms and/or physiological conditions. MT-dependent MT nucleation is particularly noticeable in plant cells because it accounts for the primary source of MT generation for assembling spindle, phragmoplast, and cortical arrays when the γ-tubulin ring complex is anchored and activated by the augmin complex. It is intriguing what proteins are associated with plant-specific MTOCs and how plant cells activate or inactivate MT nucleation activities in spatiotemporally regulated manners.
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Affiliation(s)
- Yuh-Ru Julie Lee
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Bo Liu
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
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35
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Thawani A, Stone HA, Shaevitz JW, Petry S. Spatiotemporal organization of branched microtubule networks. eLife 2019; 8:43890. [PMID: 31066674 PMCID: PMC6519983 DOI: 10.7554/elife.43890] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/07/2019] [Indexed: 11/13/2022] Open
Abstract
To understand how chromosomes are segregated, it is necessary to explain the precise spatiotemporal organization of microtubules (MTs) in the mitotic spindle. We use Xenopus egg extracts to study the nucleation and dynamics of MTs in branched networks, a process that is critical for spindle assembly. Surprisingly, new branched MTs preferentially originate near the minus-ends of pre-existing MTs. A sequential reaction model, consisting of deposition of nucleation sites on an existing MT, followed by rate-limiting nucleation of branches, reproduces the measured spatial profile of nucleation, the distribution of MT plus-ends and tubulin intensity. By regulating the availability of the branching effectors TPX2, augmin and γ-TuRC, combined with single-molecule observations, we show that first TPX2 is deposited on pre-existing MTs, followed by binding of augmin/γ-TuRC to result in the nucleation of branched MTs. In sum, regulating the localization and kinetics of nucleation effectors governs the architecture of branched MT networks.
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Affiliation(s)
- Akanksha Thawani
- Department of Chemical and Biological Engineering, Princeton University, Princeton, United States
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, United States
| | - Joshua W Shaevitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, United States.,Department of Physics, Princeton University, Princeton, United States
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, United States
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36
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Kozgunova E, Nishina M, Goshima G. Kinetochore protein depletion underlies cytokinesis failure and somatic polyploidization in the moss Physcomitrella patens. eLife 2019; 8:43652. [PMID: 30835203 PMCID: PMC6433463 DOI: 10.7554/elife.43652] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/04/2019] [Indexed: 12/17/2022] Open
Abstract
Lagging chromosome is a hallmark of aneuploidy arising from errors in the kinetochore–spindle attachment in animal cells. However, kinetochore components and cellular phenotypes associated with kinetochore dysfunction are much less explored in plants. Here, we carried out a comprehensive characterization of conserved kinetochore components in the moss Physcomitrella patens and uncovered a distinct scenario in plant cells regarding both the localization and cellular impact of the kinetochore proteins. Most surprisingly, knock-down of several kinetochore proteins led to polyploidy, not aneuploidy, through cytokinesis failure in >90% of the cells that exhibited lagging chromosomes for several minutes or longer. The resultant cells, containing two or more nuclei, proceeded to the next cell cycle and eventually developed into polyploid plants. As lagging chromosomes have been observed in various plant species in the wild, our observation raised a possibility that they could be one of the natural pathways to polyploidy in plants. Plants and animals, like all living things, are made of self-contained units called cells that are able to grow and multiply as required. Each cell contains structures called chromosomes that provide the genetic instructions needed to perform every task in the cell. When a cell is preparing to divide to make two identical daughter cells – a process called mitosis – it first needs to duplicate its chromosomes and separate them into two equal-sized sets. This process is carried out by complex cell machinery known as the spindle. Structures called kinetochores assemble on the chromosomes to attach them to the spindle. Previous studies in animal cells have shown that, if the kinetochores do not work properly, one or more chromosomes may be left behind when the spindle operates. These ‘lagging’ chromosomes may ultimately land up in the wrong daughter cell, resulting in one of the cells having more chromosomes than the other. This can lead to cancer or other serious diseases in animals. However, it was not known what happens in plant cells when kinetochores fail to work properly. To address this question, Kozgunova et al. used a technique called RNA interference (or RNAi for short) to temporarily interrupt the production of kinetochores in the cells of a moss called Physcomitrella patens. Unexpectedly, the experiments found that most of the moss cells with lagging chromosomes were unable to divide. Instead, they remained as single cells that had twice the number of chromosomes as normal, a condition known as polyploidy. After the effects of the RNAi wore off, these polyploid moss cells were able to divide normally and were successfully grown into moss plants with a polyploid number of chromosomes. Polyploidy is actually widespread in the plant kingdom, and it has major impacts on plant evolution. It is also known to increase the amount of food that crops produce. However, it is still unclear why polyploidy is so common in plants. By showing that errors in mitosis may also be able to double the number of chromosomes in plant cells, the findings of Kozgunova et al. provide new insights into plant evolution and, potentially, a method to increase polyploidy in crop plants in the future.
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Affiliation(s)
- Elena Kozgunova
- International Collaborative Programme in Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Momoko Nishina
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
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37
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Tang H, de Keijzer J, Overdijk EJR, Sweep E, Steentjes M, Vermeer JEM, Janson ME, Ketelaar T. Exocyst subunit Sec6 is positioned by microtubule overlaps in the moss phragmoplast prior to cell plate membrane arrival. J Cell Sci 2019; 132:jcs222430. [PMID: 30635445 DOI: 10.1242/jcs.222430] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 01/02/2019] [Indexed: 12/21/2022] Open
Abstract
During plant cytokinesis a radially expanding membrane-enclosed cell plate is formed from fusing vesicles that compartmentalizes the cell in two. How fusion is spatially restricted to the site of cell plate formation is unknown. Aggregation of cell-plate membrane starts near regions of microtubule overlap within the bipolar phragmoplast apparatus of the moss Physcomitrella patens Since vesicle fusion generally requires coordination of vesicle tethering and subsequent fusion activity, we analyzed the subcellular localization of several subunits of the exocyst, a tethering complex active during plant cytokinesis. We found that the exocyst complex subunit Sec6 but not the Sec3 or Sec5 subunits localized to microtubule overlap regions in advance of cell plate construction in moss. Moreover, Sec6 exhibited a conserved physical interaction with an ortholog of the Sec1/Munc18 protein KEULE, an important regulator for cell-plate membrane vesicle fusion in Arabidopsis Recruitment of the P. patens protein KEULE and vesicles to the early cell plate was delayed upon Sec6 gene silencing. Our findings, thus, suggest that vesicle-vesicle fusion is, in part, enabled by a pool of exocyst subunits at microtubule overlaps, which is recruited independently of vesicle delivery.
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Affiliation(s)
- Han Tang
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Jeroen de Keijzer
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Elysa J R Overdijk
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Els Sweep
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Maikel Steentjes
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Joop E M Vermeer
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- Department of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, 8008 Zurich, Switzerland
| | - Marcel E Janson
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Tijs Ketelaar
- Laboratory of Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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Sakai K, Charlot F, Le Saux T, Bonhomme S, Nogué F, Palauqui JC, Fattaccioli J. Design of a comprehensive microfluidic and microscopic toolbox for the ultra-wide spatio-temporal study of plant protoplasts development and physiology. PLANT METHODS 2019; 15:79. [PMID: 31367225 PMCID: PMC6651895 DOI: 10.1186/s13007-019-0459-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 07/06/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Plant protoplasts are basic plant cells units in which the pecto-cellulosic cell wall has been removed, but the plasma membrane is intact. One of the main features of plant cells is their strong plasticity, and their propensity to regenerate an organism from a single cell. Methods and differentiation protocols used in plant physiology and biology usually involve macroscopic vessels and containers that make difficult, for example, to follow the fate of the same protoplast all along its full development cycle, but also to perform continuous studies of the influence of various gradients in this context. These limits have hampered the precise study of regeneration processes. RESULTS Herein, we present the design of a comprehensive, physiologically relevant, easy-to-use and low-cost microfluidic and microscopic setup for the monitoring of Physcomitrella patens (P. patens) growth and development on a long-term basis. The experimental solution we developed is made of two parts (i) a microfluidic chip composed of a single layer of about a hundred flow-through microfluidic traps for the immobilization of protoplasts, and (ii) a low-cost, light-controlled, custom-made microscope allowing the continuous recording of the moss development in physiological conditions. We validated the experimental setup with three proofs of concepts: (i) the kinetic monitoring of first division steps and cell wall regeneration, (ii) the influence of the photoperiod on growth of the protonemata, and (iii) finally the induction of leafy buds using a phytohormone, cytokinin. CONCLUSIONS We developed the design of a comprehensive, physiologically relevant, easy-to-use and low-cost experimental setup for the study of P. patens development in a microfluidic environment. This setup allows imaging of P. patens development at high resolution and over long time periods.
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Affiliation(s)
- Kaori Sakai
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
| | - Florence Charlot
- INRA, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
| | - Thomas Le Saux
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Sandrine Bonhomme
- INRA, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
| | - Fabien Nogué
- INRA, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
| | - Jean-Christophe Palauqui
- INRA, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, Versailles, France
| | - Jacques Fattaccioli
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
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Yi P, Goshima G. Microtubule nucleation and organization without centrosomes. CURRENT OPINION IN PLANT BIOLOGY 2018; 46:1-7. [PMID: 29981930 DOI: 10.1016/j.pbi.2018.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/11/2018] [Accepted: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Centrosomes play various critical roles in animal cells such as microtubule nucleation and stabilization, mitotic spindle morphogenesis, and spindle orientation. Land plants have lost centrosomes and yet must execute many of these functions. Recent studies have revealed the crucial roles played by morphologically distinct cytoplasmic microtubule-organizing centers (MTOCs) in initiating spindle bipolarity and maintaining spindle orientation robustness. These MTOCs resemble centrosomes in many aspects, implying an evolutionary divergence of MT-organizing structures in plants. However, their functions rely on conserved nucleation and amplification mechanisms, indicating a similarity in MT network establishment between animals and plants. Moreover, recent characterization of a plant-specific MT minus-end tracking protein suggests that plants have developed functionally equivalent modules to stabilize and organize MTs at minus ends. These findings support the theory that plants overcome centrosome loss by utilizing modified but substantially conserved mechanisms to organize MT networks.
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Affiliation(s)
- Peishan Yi
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
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40
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Yamada M, Goshima G. The KCH Kinesin Drives Nuclear Transport and Cytoskeletal Coalescence to Promote Tip Cell Growth in Physcomitrella patens. THE PLANT CELL 2018; 30:1496-1510. [PMID: 29880712 PMCID: PMC6096588 DOI: 10.1105/tpc.18.00038] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/01/2018] [Accepted: 06/07/2018] [Indexed: 05/03/2023]
Abstract
Long-distance transport along microtubules (MTs) is critical for intracellular organization. In animals, antagonistic motor proteins kinesin (plus end directed) and dynein (minus end directed) drive cargo transport. In land plants, however, the identity of motors responsible for transport is poorly understood, as genes encoding cytoplasmic dynein are absent in plant genomes. How other functions of dynein are brought about in plants also remains unknown. Here, we show that a subclass of the kinesin-14 family, KCH (kinesin with calponin homology domain), which can also bind actin, drives MT minus end-directed nuclear transport in the moss Physcomitrella patens When all four KCH genes were deleted, the nucleus was not maintained in the cell center but was translocated to the apical end of protonemal cells. In the knockout (KO) line, apical cell tip growth was also severely suppressed. KCH was localized to MTs, including at the MT focal point near the tip of protonemal cells, where MT plus ends coalesced with actin filaments. MT focus was not stably maintained in KCH KO lines, whereas actin destabilization also disrupted the MT focus in wild-type lines despite KCH remaining on unfocused MTs. KCH had distinct functions in nuclear transport and tip growth, as a truncated KCH construct restored nuclear transport activity, but not tip growth retardation of the KO line. Thus, our study identified KCH as a long-distance retrograde transporter as well as a MT cross-linker, reminiscent of the versatile animal dynein.
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Affiliation(s)
- Moé Yamada
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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41
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Simultaneous imaging and functional studies reveal a tight correlation between calcium and actin networks. Proc Natl Acad Sci U S A 2018; 115:E2869-E2878. [PMID: 29507239 DOI: 10.1073/pnas.1711037115] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Tip-growing cells elongate in a highly polarized manner via focused secretion of flexible cell-wall material. Calcium has been implicated as a vital factor in regulating the deposition of cell-wall material. However, deciphering the molecular and mechanistic calcium targets in vivo has remained challenging. Here, we investigated intracellular calcium dynamics in the moss Physcomitrella patens, which provides a system with an abundant source of genetically identical tip-growing cells, excellent cytology, and a large molecular genetic tool kit. To visualize calcium we used a genetically encoded cytosolic FRET probe, revealing a fluctuating tipward gradient with a complex oscillatory profile. Wavelet analysis coupled with a signal-sifting algorithm enabled the quantitative comparison of the calcium behavior in cells where growth was inhibited mechanically, pharmacologically, or genetically. We found that cells with suppressed growth have calcium oscillatory profiles with longer frequencies, suggesting that there is a feedback between the calcium gradient and growth. To investigate the mechanistic basis for this feedback we simultaneously imaged cytosolic calcium and actin, which has been shown to be essential for tip growth. We found that high cytosolic calcium promotes disassembly of a tip-focused actin spot, while low calcium promotes assembly. In support of this, abolishing the calcium gradient resulted in dramatic actin accumulation at the tip. Together these data demonstrate that tipward calcium is quantitatively linked to actin accumulation in vivo and that the moss P. patens provides a powerful system to uncover mechanistic links between calcium, actin, and growth.
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42
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Smertenko A, Hewitt SL, Jacques CN, Kacprzyk R, Liu Y, Marcec MJ, Moyo L, Ogden A, Oung HM, Schmidt S, Serrano-Romero EA. Phragmoplast microtubule dynamics - a game of zones. J Cell Sci 2018; 131:jcs.203331. [PMID: 29074579 DOI: 10.1242/jcs.203331] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Plant morphogenesis relies on the accurate positioning of the partition (cell plate) between dividing cells during cytokinesis. The cell plate is synthetized by a specialized structure called the phragmoplast, which consists of microtubules, actin filaments, membrane compartments and associated proteins. The phragmoplast forms between daughter nuclei during the transition from anaphase to telophase. As cells are commonly larger than the originally formed phragmoplast, the construction of the cell plate requires phragmoplast expansion. This expansion depends on microtubule polymerization at the phragmoplast forefront (leading zone) and loss at the back (lagging zone). Leading and lagging zones sandwich the 'transition' zone. A population of stable microtubules in the transition zone facilitates transport of building materials to the midzone where the cell plate assembly takes place. Whereas microtubules undergo dynamic instability in all zones, the overall balance appears to be shifted towards depolymerization in the lagging zone. Polymerization of microtubules behind the lagging zone has not been reported to date, suggesting that microtubule loss there is irreversible. In this Review, we discuss: (1) the regulation of microtubule dynamics in the phragmoplast zones during expansion; (2) mechanisms of the midzone establishment and initiation of cell plate biogenesis; and (3) signaling in the phragmoplast.
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Affiliation(s)
- Andrei Smertenko
- Institute of Biological Chemistry, Pullman, WA 99164, USA .,Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA
| | - Seanna L Hewitt
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,Department of Horticulture, Washington State University, Pullman, WA 99164, USA
| | - Caitlin N Jacques
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,Department of Crop and Soil Sciences, Washington State University, Pullman, WA 99164, USA
| | - Rafal Kacprzyk
- Institute of Biological Chemistry, Pullman, WA 99164, USA
| | - Yan Liu
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
| | - Matthew J Marcec
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,Department of Plant Pathology, Washington State University, Pullman, WA 99164, USA
| | - Lindani Moyo
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,Department of Plant Pathology, Washington State University, Pullman, WA 99164, USA
| | - Aaron Ogden
- Institute of Biological Chemistry, Pullman, WA 99164, USA.,Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA
| | - Hui Min Oung
- Institute of Biological Chemistry, Pullman, WA 99164, USA.,Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA
| | - Sharol Schmidt
- Institute of Biological Chemistry, Pullman, WA 99164, USA.,Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA
| | - Erika A Serrano-Romero
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA 99164, USA.,School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
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43
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Lee YRJ, Hiwatashi Y, Hotta T, Xie T, Doonan JH, Liu B. The Mitotic Function of Augmin Is Dependent on Its Microtubule-Associated Protein Subunit EDE1 in Arabidopsis thaliana. Curr Biol 2017; 27:3891-3897.e4. [DOI: 10.1016/j.cub.2017.11.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/30/2017] [Accepted: 11/09/2017] [Indexed: 01/13/2023]
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44
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Kosetsu K, Murata T, Yamada M, Nishina M, Boruc J, Hasebe M, Van Damme D, Goshima G. Cytoplasmic MTOCs control spindle orientation for asymmetric cell division in plants. Proc Natl Acad Sci U S A 2017; 114:E8847-E8854. [PMID: 28973935 PMCID: PMC5651782 DOI: 10.1073/pnas.1713925114] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Proper orientation of the cell division axis is critical for asymmetric cell divisions that underpin cell differentiation. In animals, centrosomes are the dominant microtubule organizing centers (MTOC) and play a pivotal role in axis determination by orienting the mitotic spindle. In land plants that lack centrosomes, a critical role of a microtubular ring structure, the preprophase band (PPB), has been observed in this process; the PPB is required for orienting (before prophase) and guiding (in telophase) the mitotic apparatus. However, plants must possess additional mechanisms to control the division axis, as certain cell types or mutants do not form PPBs. Here, using live imaging of the gametophore of the moss Physcomitrella patens, we identified acentrosomal MTOCs, which we termed "gametosomes," appearing de novo and transiently in the prophase cytoplasm independent of PPB formation. We show that gametosomes are dispensable for spindle formation but required for metaphase spindle orientation. In some cells, gametosomes appeared reminiscent of the bipolar MT "polar cap" structure that forms transiently around the prophase nucleus in angiosperms. Specific disruption of the polar caps in tobacco cells misoriented the metaphase spindles and frequently altered the final division plane, indicating that they are functionally analogous to the gametosomes. These results suggest a broad use of transient MTOC structures as the spindle orientation machinery in plants, compensating for the evolutionary loss of centrosomes, to secure the initial orientation of the spindle in a spatial window that allows subsequent fine-tuning of the division plane axis by the guidance machinery.
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Affiliation(s)
- Ken Kosetsu
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Takashi Murata
- Division of Evolutionary Biology, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Myodaiji-cho, Okazaki 444-8585, Japan
| | - Moé Yamada
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Momoko Nishina
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Joanna Boruc
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Mitsuyasu Hasebe
- Division of Evolutionary Biology, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Myodaiji-cho, Okazaki 444-8585, Japan
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium;
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan;
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45
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Roostalu J, Surrey T. Microtubule nucleation: beyond the template. Nat Rev Mol Cell Biol 2017; 18:702-710. [PMID: 28831203 DOI: 10.1038/nrm.2017.75] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microtubules are cytoskeletal filaments central to a wide range of essential cellular functions in eukaryotic cells. Consequently, cells need to exert tight control over when, where and how many microtubules are being made. Whereas the regulation of microtubule dynamics is well studied, the molecular mechanisms of microtubule nucleation are still poorly understood. Next to the established master template of nucleation, the γ-tubulin ring complex, other microtubule-associated proteins that affect microtubule dynamic properties have recently been found to contribute to nucleation. It has begun to emerge that the nucleation efficiency is controlled not only by template activity but also by, either additionally or alternatively, the stabilization of the nascent microtubule 'nucleus'. This suggests a simple conceptual framework for the mechanisms regulating microtubule nucleation in cells.
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Affiliation(s)
| | - Thomas Surrey
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
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46
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Russell JJ, Theriot JA, Sood P, Marshall WF, Landweber LF, Fritz-Laylin L, Polka JK, Oliferenko S, Gerbich T, Gladfelter A, Umen J, Bezanilla M, Lancaster MA, He S, Gibson MC, Goldstein B, Tanaka EM, Hu CK, Brunet A. Non-model model organisms. BMC Biol 2017; 15:55. [PMID: 28662661 PMCID: PMC5492503 DOI: 10.1186/s12915-017-0391-5] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Model organisms are widely used in research as accessible and convenient systems to study a particular area or question in biology. Traditionally only a handful of organisms have been widely studied, but modern research tools are enabling researchers to extend the set of model organisms to include less-studied and more unusual systems. This Forum highlights a range of 'non-model model organisms' as emerging systems for tackling questions across the whole spectrum of biology (and beyond), the opportunities and challenges, and the outlook for the future.
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Affiliation(s)
- James J Russell
- Department of Biology, Howard Hughes Medical Institute Stanford University, Stanford, CA, 94305, USA
| | - Julie A Theriot
- Departments of Biochemistry and of Microbiology & Immunology, Howard Hughes Medical Institute Stanford University, Stanford, CA, 94305, USA.
| | - Pranidhi Sood
- Department of Biochemistry & Biophysics, University of California San Francisco, 600 16th St, San Francisco, CA, 94158, USA
| | - Wallace F Marshall
- Department of Biochemistry & Biophysics, University of California San Francisco, 600 16th St, San Francisco, CA, 94158, USA.
| | - Laura F Landweber
- Departments of Biochemistry & Molecular Biophysics and Biological Sciences, Columbia University, New York, NY, 10032, USA
| | | | - Jessica K Polka
- Visiting Scholar, Whitehead Institute, 9 Cambridge Center, Cambridge, MA, 02142, USA
| | - Snezhana Oliferenko
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London, SE1 1UL, UK
| | - Therese Gerbich
- 516 Fordham Hall, University of North Carolina Chapel Hill, Chapel Hill, NC, 27514, USA
| | - Amy Gladfelter
- 516 Fordham Hall, University of North Carolina Chapel Hill, Chapel Hill, NC, 27514, USA
| | - James Umen
- Donald Danforth Plant Science Center, 975 N. Warson Rd, St. Louis, MO, 63132, USA
| | | | - Madeline A Lancaster
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, CB2 0QH, Cambridge, UK
| | - Shuonan He
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Matthew C Gibson
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- Department of Anatomy and Cell Biology, The University of Kansas School of Medicine, Kansas City, KS, 66160, USA
| | - Bob Goldstein
- Biology Department, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Elly M Tanaka
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus Vienna Biocenter 1, 1030, Vienna, Austria
| | - Chi-Kuo Hu
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
- Glenn Laboratories for the Biology of Aging at Stanford, Stanford, CA, 94305, USA
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47
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Yamada M, Tanaka-Takiguchi Y, Hayashi M, Nishina M, Goshima G. Multiple kinesin-14 family members drive microtubule minus end-directed transport in plant cells. J Cell Biol 2017; 216:1705-1714. [PMID: 28442535 PMCID: PMC5461021 DOI: 10.1083/jcb.201610065] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 02/05/2017] [Accepted: 03/17/2017] [Indexed: 12/25/2022] Open
Abstract
Minus end-directed cargo transport along microtubules (MTs) is exclusively driven by the molecular motor dynein in a wide variety of cell types. Interestingly, during evolution, plants have lost the genes encoding dynein; the MT motors that compensate for dynein function are unknown. Here, we show that two members of the kinesin-14 family drive minus end-directed transport in plants. Gene knockout analyses of the moss Physcomitrella patens revealed that the plant-specific class VI kinesin-14, KCBP, is required for minus end-directed transport of the nucleus and chloroplasts. Purified KCBP directly bound to acidic phospholipids and unidirectionally transported phospholipid liposomes along MTs in vitro. Thus, minus end-directed transport of membranous cargoes might be driven by their direct interaction with this motor protein. Newly nucleated cytoplasmic MTs represent another known cargo exhibiting minus end-directed motility, and we identified the conserved class I kinesin-14 (ATK) as the motor involved. These results suggest that kinesin-14 motors were duplicated and developed as alternative MT-based minus end-directed transporters in land plants.
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Affiliation(s)
- Moé Yamada
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Yohko Tanaka-Takiguchi
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Masahito Hayashi
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Momoko Nishina
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
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48
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Yamada M, Goshima G. Mitotic Spindle Assembly in Land Plants: Molecules and Mechanisms. BIOLOGY 2017; 6:biology6010006. [PMID: 28125061 PMCID: PMC5371999 DOI: 10.3390/biology6010006] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 11/29/2016] [Accepted: 01/08/2017] [Indexed: 11/16/2022]
Abstract
In textbooks, the mitotic spindles of plants are often described separately from those of animals. How do they differ at the molecular and mechanistic levels? In this chapter, we first outline the process of mitotic spindle assembly in animals and land plants. We next discuss the conservation of spindle assembly factors based on database searches. Searches of >100 animal spindle assembly factors showed that the genes involved in this process are well conserved in plants, with the exception of two major missing elements: centrosomal components and subunits/regulators of the cytoplasmic dynein complex. We then describe the spindle and phragmoplast assembly mechanisms based on the data obtained from robust gene loss-of-function analyses using RNA interference (RNAi) or mutant plants. Finally, we discuss future research prospects of plant spindles.
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Affiliation(s)
- Moé Yamada
- Graduate School of Science, Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
| | - Gohta Goshima
- Graduate School of Science, Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
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49
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Liu S, Yoder JI. Chemical induction of hairpin RNAi molecules to silence vital genes in plant roots. Sci Rep 2016; 6:37711. [PMID: 27898105 PMCID: PMC5127191 DOI: 10.1038/srep37711] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 11/02/2016] [Indexed: 11/29/2022] Open
Abstract
Understanding the functions encoded by plant genes can be facilitated by reducing transcript levels by hairpin RNA (hpRNA) mediated silencing. A bottleneck to this technology occurs when a gene encodes a phenotype that is necessary for cell viability and silencing the gene inhibits transformation. Here we compared the use of two chemically inducible plant promoter systems to drive hpRNA mediated gene silencing in transgenic, hairy roots. We cloned the gene encoding the Yellow Fluorescence Protein (YFP) into the dexamethasone inducible vector pOpOff2 and into the estradiol induced vector pER8. We then cloned a hpRNA targeting YFP under the regulation of the inducible promoters, transformed Medicago truncatula roots, and quantified YFP fluorescence and mRNA levels. YFP fluorescence was normal in pOpOff2 transformed roots without dexamethasone but was reduced with dexamethasone treatment. Interestingly, dexamethasone removal did not reverse YFP inhibition. YFP expression in roots transformed with pER8 was low even in the absence of inducer. We used the dexamethasone system to silence acetyl-CoA carboxylase gene and observed prolific root growth when this construct was transformed into Medicago until dexamethasone was applied. Our study shows that dexamethasone inducibility can be useful to silence vital genes in transgenic roots.
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Affiliation(s)
- Siming Liu
- Plant Sciences Department, University of California, Davis, CA 95616, USA
| | - John I. Yoder
- Plant Sciences Department, University of California, Davis, CA 95616, USA
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50
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Simple and Efficient Targeting of Multiple Genes Through CRISPR-Cas9 in Physcomitrella patens. G3-GENES GENOMES GENETICS 2016; 6:3647-3653. [PMID: 27613750 PMCID: PMC5100863 DOI: 10.1534/g3.116.033266] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Powerful genome editing technologies are needed for efficient gene function analysis. The CRISPR-Cas9 system has been adapted as an efficient gene-knock-out technology in a variety of species. However, in a number of situations, knocking out or modifying a single gene is not sufficient; this is particularly true for genes belonging to a common family, or for genes showing redundant functions. Like many plants, the model organism Physcomitrella patens has experienced multiple events of polyploidization during evolution that has resulted in a number of families of duplicated genes. Here, we report a robust CRISPR-Cas9 system, based on the codelivery of a CAS9 expressing cassette, multiple sgRNA vectors, and a cassette for transient transformation selection, for gene knock-out in multiple gene families. We demonstrate that CRISPR-Cas9-mediated targeting of five different genes allows the selection of a quintuple mutant, and all possible subcombinations of mutants, in one experiment, with no mutations detected in potential off-target sequences. Furthermore, we confirmed the observation that the presence of repeats in the vicinity of the cutting region favors deletion due to the alternative end joining pathway, for which induced frameshift mutations can be potentially predicted. Because the number of multiple gene families in Physcomitrella is substantial, this tool opens new perspectives to study the role of expanded gene families in the colonization of land by plants.
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