1
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Wallner ES, Mair A, Handler D, McWhite C, Xu SL, Dolan L, Bergmann DC. Spatially resolved proteomics of the Arabidopsis stomatal lineage identifies polarity complexes for cell divisions and stomatal pores. Dev Cell 2024; 59:1096-1109.e5. [PMID: 38518768 DOI: 10.1016/j.devcel.2024.03.001] [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: 12/14/2023] [Revised: 02/23/2024] [Accepted: 03/05/2024] [Indexed: 03/24/2024]
Abstract
Cell polarity is used to guide asymmetric divisions and create morphologically diverse cells. We find that two oppositely oriented cortical polarity domains present during the asymmetric divisions in the Arabidopsis stomatal lineage are reconfigured into polar domains marking ventral (pore-forming) and outward-facing domains of maturing stomatal guard cells. Proteins that define these opposing polarity domains were used as baits in miniTurboID-based proximity labeling. Among differentially enriched proteins, we find kinases, putative microtubule-interacting proteins, and polar SOSEKIs with their effector ANGUSTIFOLIA. Using AI-facilitated protein structure prediction models, we identify potential protein-protein interaction interfaces among them. Functional and localization analyses of the polarity protein OPL2 and its putative interaction partners suggest a positive interaction with mitotic microtubules and a role in cytokinesis. This combination of proteomics and structural modeling with live-cell imaging provides insights into how polarity is rewired in different cell types and cell-cycle stages.
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Affiliation(s)
- Eva-Sophie Wallner
- Department of Biology, Stanford University, Stanford, CA 94305-5020, USA; Gregor Mendel Institute, Dr. Bohr-Gasse 3, 1030 Wien, Austria; Howard Hughes Medical Institute, Stanford, CA 94305, USA.
| | - Andrea Mair
- Howard Hughes Medical Institute, Stanford, CA 94305, USA
| | | | - Claire McWhite
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Shou-Ling Xu
- Carnegie Institution for Science, Stanford, CA 94305, USA; Carnegie Mass Spectrometry Facility, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Liam Dolan
- Gregor Mendel Institute, Dr. Bohr-Gasse 3, 1030 Wien, Austria
| | - Dominique C Bergmann
- Department of Biology, Stanford University, Stanford, CA 94305-5020, USA; Howard Hughes Medical Institute, Stanford, CA 94305, USA.
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2
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Blanco-Touriñán N, Hardtke CS. Connecting emerging with existing vasculature above and below ground. CURRENT OPINION IN PLANT BIOLOGY 2023; 76:102461. [PMID: 37774454 DOI: 10.1016/j.pbi.2023.102461] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/29/2023] [Accepted: 09/03/2023] [Indexed: 10/01/2023]
Abstract
The vascular system was essential for plants to colonize land by facilitating the transport of water, nutrients, and minerals throughout the body. Our current knowledge on the molecular-genetic control of vascular tissue specification and differentiation is mostly based on studies in the Arabidopsis primary root. To what degree these regulatory mechanisms in the root meristem can be extrapolated to vascular tissue development in other organs is a question of great interest. In this review, we discuss the most recent progress on cotyledon vein formation, with a focus on polar auxin transport-dependent and -independent mechanisms. We also provide an overview of vasculature formation in postembryonic organs, namely lateral roots, which is more complex than anticipated as several tissues of the parent root must act in a spatio-temporally coordinated manner.
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Affiliation(s)
- Noel Blanco-Touriñán
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, 1015 Lausanne, Switzerland.
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, 1015 Lausanne, Switzerland.
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3
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Muniz AC, de Oliveira Buzatti RS, de Lemos-Filho JP, Heuertz M, Nazareno AG, Lovato MB. Genomic signatures of ecological divergence between savanna and forest populations of a Neotropical tree. ANNALS OF BOTANY 2023; 132:523-540. [PMID: 37642427 PMCID: PMC10667007 DOI: 10.1093/aob/mcad120] [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: 05/01/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023]
Abstract
BACKGROUND AND AIMS In eastern Neotropical South America, the Cerrado, a large savanna vegetation, and the Atlantic Forest harbour high biodiversity levels, and their habitats are rather different from each other. The biomes have intrinsic evolutionary relationships, with high lineage exchange that can be attributed, in part, to a large contact zone between them. The genomic study of ecotypes, i.e. populations adapted to divergent habitats, can be a model to study the genomic signatures of ecological divergence. Here, we investigated two ecotypes of the tree Plathymenia reticulata, one from the Cerrado and the other from the Atlantic Forest, which have a hybrid zone in the ecotonal zone of Atlantic Forest-Cerrado. METHODS The ecotypes were sampled in the two biomes and their ecotone. The evolutionary history of the divergence of the species was analysed with double-digest restriction site-associated DNA sequencing. The genetic structure and the genotypic composition of the hybrid zone were determined. Genotype-association analyses were performed, and the loci under putative selection and their functions were investigated. KEY RESULTS High divergence between the two ecotypes was found, and only early-generation hybrids were found in the hybrid zone, suggesting a partial reproductive barrier. Ancient introgression between the Cerrado and Atlantic Forest was not detected. The soil and climate were associated with genetic divergence in Plathymenia ecotypes and outlier loci were found to be associated with the stress response, with stomatal and root development and with reproduction. CONCLUSIONS The high genomic, ecological and morphophysiological divergence between ecotypes, coupled with partial reproductive isolation, indicate that the ecotypes represent two species and should be managed as different evolutionary lineages. We advise that the forest species should be re-evaluated and restated as vulnerable. Our results provide insights into the genomic mechanisms underlying the diversification of species across savanna and forest habitats and the evolutionary forces acting in the species diversification in the Neotropics.
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Affiliation(s)
- André Carneiro Muniz
- Departamento de Genética, Ecologia e Evolução, Universidade Federal de Minas Gerais, CP 486, Belo Horizonte, MG 31270-901, Brazil
| | | | - José Pires de Lemos-Filho
- Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Myriam Heuertz
- Biogeco, INRAE, Univ. Bordeaux, 69 route d’Arcachon, 33610 Cestas, France
| | - Alison Gonçalves Nazareno
- Departamento de Genética, Ecologia e Evolução, Universidade Federal de Minas Gerais, CP 486, Belo Horizonte, MG 31270-901, Brazil
| | - Maria Bernadete Lovato
- Departamento de Genética, Ecologia e Evolução, Universidade Federal de Minas Gerais, CP 486, Belo Horizonte, MG 31270-901, Brazil
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4
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Wallner ES, Dolan L, Bergmann DC. Arabidopsis stomatal lineage cells establish bipolarity and segregate differential signaling capacity to regulate stem cell potential. Dev Cell 2023; 58:1643-1656.e5. [PMID: 37607546 DOI: 10.1016/j.devcel.2023.07.024] [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: 02/14/2023] [Revised: 04/04/2023] [Accepted: 07/31/2023] [Indexed: 08/24/2023]
Abstract
Cell polarity combined with asymmetric cell divisions (ACDs) generates cellular diversity. In the Arabidopsis stomatal lineage, a single cortical polarity domain marked by BASL orients ACDs and is segregated to the larger daughter to enforce cell fate. We discovered a second, oppositely positioned polarity domain defined by OCTOPUS-LIKE (OPL) proteins, which forms prior to ACD and is segregated to the smaller (meristemoid) daughter. Genetic and misexpression analyses show that OPLs promote meristemoid-amplifying divisions and delay stomatal fate progression. Polarity mediates OPL segregation into meristemoids but is not required for OPL function. OPL localization and activity are largely independent of other stomatal polarity genes and of the brassinosteroid signaling components associated with OPLs in other contexts. While OPLs are unique to seed plants, ectopic expression in the liverwort Marchantia suppressed epidermal fate progression, suggesting that OPLs engage ancient and broadly conserved pathways to regulate cell division and cell fate.
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Affiliation(s)
- Eva-Sophie Wallner
- Department of Biology, Stanford University, Stanford, CA 94305-5020, USA; Gregor Mendel Institute, Dr.-Bohr-Gasse 3, 1030 Wien, Austria; Howard Hughes Medical Institute, Stanford, CA 94305, USA.
| | - Liam Dolan
- Gregor Mendel Institute, Dr.-Bohr-Gasse 3, 1030 Wien, Austria
| | - Dominique C Bergmann
- Department of Biology, Stanford University, Stanford, CA 94305-5020, USA; Howard Hughes Medical Institute, Stanford, CA 94305, USA.
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5
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Greenwood KN, King CL, Melena I, Stegemann KA, Donnelly M, Childers A, Mozal R, Collins CA, Spears BJ. The brassinosteroid-responsive protein OCTOPUS is a novel regulator of Arabidopsis thaliana immune signaling. PLANT DIRECT 2023; 7:e524. [PMID: 37638229 PMCID: PMC10448135 DOI: 10.1002/pld3.524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/27/2023] [Indexed: 08/29/2023]
Abstract
Phloem is a critical tissue for transport of photosynthates and extracellular signals in vascular plants. However, it also represents an ideal environment for pathogens seeking access to valuable host nutrients. Although many vascular pathogens induce economically relevant crop damage, there is still little known about the mechanisms by which immune signaling operates through the phloem. An existing phosphoproteomic dataset was mined to identify proteins that were both phosphorylated in response to the defense-elicitor flagellin (flg22) and expressed in vascular cells. A single candidate, OCTOPUS (OPS), is polarly associated with the plasma membrane of sieve element cells and has been characterized as an inhibitor of brassinosteroid insensitive-2 in promotion of brassinosteroid-related phytohormone signaling. The observation that OPS is differentially phosphorylated in response to flg22 led us to the examine whether OPS may also regulate flg22-induced immune signaling. Two independent alleles of ops exhibited enhanced immunity outputs across multiple signaling branches of PAMP-triggered immunity (PTI), constitutively and in response to flg22 treatment. Together with our observation that interactions between OPS and brassinosteroid insensitive-2 were disrupted by induction of salicylic acid and depletion of brassinosteriod, these data support a model whereby OPS modulates brassinolide and immune signaling to control downstream responses. We present OPS as a novel addition to the list of proteins with documented roles in PAMP-PTI signaling. These results further indicate that immune signaling in the phloem may be a significant and unique component of the host detection and response to pathogens in vascular plants.
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Affiliation(s)
- Kaitlyn N. Greenwood
- Department of Chemistry and PhysicsDrury UniversitySpringfieldMissouriUSA
- Present address:
DaVita DialysisOverland ParkKansasUSA
| | - Courtney L. King
- Department of Chemistry and PhysicsDrury UniversitySpringfieldMissouriUSA
- Present address:
Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndianaUSA
| | - Isabella Melena
- Department of Chemistry and PhysicsDrury UniversitySpringfieldMissouriUSA
- Present address:
School of MedicineWashington University in St. LouisSt. LouisMissouriUSA
| | - Katherine A. Stegemann
- Department of BiologyMarian UniversityIndianapolisIndianaUSA
- Present address:
Krannert School of Physical TherapyUniversity of IndianapolisIndianapolisIndianaUSA
| | - Maura Donnelly
- Present address:
Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Anna Childers
- Present address:
Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Raegan Mozal
- Present address:
Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Carina A. Collins
- Department of Chemistry and PhysicsDrury UniversitySpringfieldMissouriUSA
- Department of BiologyMarian UniversityIndianapolisIndianaUSA
- Present address:
Eli Lilly and CompanyLilly Corporate CenterIndianapolisIndianaUSA
| | - Benjamin J. Spears
- Present address:
Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
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6
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Pandey SS, Xu J, Achor DS, Li J, Wang N. Microscopic and Transcriptomic Analyses of Early Events Triggered by ' Candidatus Liberibacter asiaticus' in Young Flushes of Huanglongbing-Positive Citrus Trees. PHYTOPATHOLOGY 2023; 113:985-997. [PMID: 36449527 DOI: 10.1094/phyto-10-22-0360-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
'Candidatus Liberibacter asiaticus' (CLas) is associated with the devastating citrus disease Huanglongbing (HLB). Young flushes are the center of the HLB pathosystem due to their roles in the psyllid life cycle and in the acquisition and transmission of CLas. However, the early events of CLas infection and how CLas modulates young flush physiology remain poorly understood. Here, transmission electron microscopy analysis showed that the mean diameter of the sieve pores decreased in young leaves of HLB-positive trees after CLas infection, consistent with CLas-triggered callose deposition. RNA-seq-based global expression analysis of young leaves of HLB-positive sweet orange with (CLas-Pos) and without (CLas-Neg) detectable CLas demonstrated a significant impact on gene expression in young leaves, including on the expression of genes involved in host immunity, stress response, and plant hormone biosynthesis and signaling. CLas-Pos and CLas-Neg expression data displayed distinct patterns. The number of upregulated genes was higher than that of the downregulated genes in CLas-Pos for plant-pathogen interactions, glutathione metabolism, peroxisome, and calcium signaling, which are commonly associated with pathogen infections, compared with the healthy control. On the contrary, the number of upregulated genes was lower than that of the downregulated genes in CLas-Neg for genes involved in plant-pathogen interactions and peroxisome biogenesis/metabolism. Additionally, a time-course quantitative reverse transcription-PCR-based expression analysis visualized the induced expression of companion cell-specific genes, phloem protein 2 genes, and sucrose transport genes in young flushes triggered by CLas. This study advances our understanding of early events during CLas infection of citrus young flushes.
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Affiliation(s)
- Sheo Shankar Pandey
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Jin Xu
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Diann S Achor
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Jinyun Li
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
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7
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Hardtke CS. Phloem development. THE NEW PHYTOLOGIST 2023. [PMID: 37243530 DOI: 10.1111/nph.19003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 04/13/2023] [Indexed: 05/29/2023]
Abstract
The evolution of the plant vascular system is a key process in Earth history because it enabled plants to conquer land and transform the terrestrial surface. Among the vascular tissues, the phloem is particularly intriguing because of its complex functionality. In angiosperms, its principal components are the sieve elements, which transport phloem sap, and their neighboring companion cells. Together, they form a functional unit that sustains sap loading, transport, and unloading. The developmental trajectory of sieve elements is unique among plant cell types because it entails selective organelle degradation including enucleation. Meticulous analyses of primary, so-called protophloem in the Arabidopsis thaliana root meristem have revealed key steps in protophloem sieve element formation at single-cell resolution. A transcription factor cascade connects specification with differentiation and also orchestrates phloem pole patterning via noncell-autonomous action of sieve element-derived effectors. Reminiscent of vascular tissue patterning in secondary growth, these involve receptor kinase pathways, whose antagonists guide the progression of sieve element differentiation. Receptor kinase pathways may also safeguard phloem formation by maintaining the developmental plasticity of neighboring cell files. Our current understanding of protophloem development in the A. thaliana root has reached sufficient detail to instruct molecular-level investigation of phloem formation in other organs.
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Affiliation(s)
- Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, CH-1015, Lausanne, Switzerland
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8
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Koh SWH, Diaz-Ardila HN, Bascom CS, Berenguer E, Ingram G, Estelle M, Hardtke CS. Heterologous expression of a lycophyte protein enhances angiosperm seedling vigor. Development 2022; 149:dev200917. [PMID: 36196593 PMCID: PMC10655917 DOI: 10.1242/dev.200917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 09/26/2022] [Indexed: 03/15/2023]
Abstract
Seedling vigor is a key agronomic trait that determines juvenile plant performance. Angiosperm seeds develop inside fruits and are connected to the mother plant through vascular tissues. Their formation requires plant-specific genes, such as BREVIS RADIX (BRX) in Arabidopsis thaliana roots. BRX family proteins are found throughout the euphyllophytes but also occur in non-vascular bryophytes and non-seed lycophytes. They consist of four conserved domains, including the tandem BRX domains. We found that bryophyte or lycophyte BRX homologs can only partially substitute for Arabidopsis BRX (AtBRX) because they miss key features in the linker between the BRX domains. Intriguingly, however, expression of a BRX homolog from the lycophyte Selaginella moellendorffii (SmBRX) in an A. thaliana wild-type background confers robustly enhanced root growth vigor that persists throughout the life cycle. This effect can be traced to a substantial increase in seed and embryo size, is associated with enhanced vascular tissue proliferation, and can be reproduced with a modified, SmBRX-like variant of AtBRX. Our results thus suggest that BRX variants can boost seedling vigor and shed light on the activity of ancient, non-angiosperm BRX family proteins.
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Affiliation(s)
- Samuel W. H. Koh
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
| | | | - Carlisle S. Bascom
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093, USA
| | - Eduardo Berenguer
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, 69364 Lyon, France
| | - Gwyneth Ingram
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, 69364 Lyon, France
| | - Mark Estelle
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093, USA
| | - Christian S. Hardtke
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
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9
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Guo X, Dong J. Protein polarization: Spatiotemporal precisions in cell division and differentiation. CURRENT OPINION IN PLANT BIOLOGY 2022; 68:102257. [PMID: 35816992 PMCID: PMC9968528 DOI: 10.1016/j.pbi.2022.102257] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/01/2022] [Accepted: 06/01/2022] [Indexed: 05/16/2023]
Abstract
Specification of cell polarity is vital to normal cell growth, morphogenesis, and function. As other eukaryotes, plants generate cellular polarity that is coordinated with tissue polarity and organ axes. In development, new cell types are generated by stem-cell division and differentiation, a process often involving proteins that are polarized to cortical domains at the plasma membrane. In the past decade, pioneering work using the model plant Arabidopsis identified multiple proteins that are polarized in dividing cells to instruct divisional behaviors and/or specify cell fates. In this review, we use these polarized cell-division regulators as example to summarize key mechanisms underlying protein polarization in plant cells. Recent progress underscores that self-organizing amplification processes are commonly involved in establishing cell polarity, and cellular polarity is influenced by both tissue-level and local mechanochemical cues. In addition, protein polarization during asymmetric cell division shows a distinct feature of temporal control in the stomatal lineage. We further discuss possible coordination between protein polarization and the progression of cell cycle in this developmental context.
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Affiliation(s)
- Xiaoyu Guo
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
| | - Juan Dong
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
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10
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Kastanaki E, Blanco-Touriñán N, Sarazin A, Sturchler A, Gujas B, Vera-Sirera F, Agustí J, Rodriguez-Villalon A. A genetic framework for proximal secondary vein branching in the Arabidopsis thaliana embryo. Development 2022; 149:275816. [PMID: 35723181 PMCID: PMC9270971 DOI: 10.1242/dev.200403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 05/09/2022] [Indexed: 01/09/2023]
Abstract
Over time, plants have evolved flexible self-organizing patterning mechanisms to adapt tissue functionality for continuous organ growth. An example of this process is the multicellular organization of cells into a vascular network in foliar organs. An important, yet poorly understood component of this process is secondary vein branching, a mechanism employed to extend vascular tissues throughout the cotyledon surface. Here, we uncover two distinct branching mechanisms during embryogenesis by analyzing the discontinuous vein network of the double mutant cotyledon vascular pattern 2 (cvp2) cvp2-like 1 (cvl1). Similar to wild-type embryos, distal veins in cvp2 cvl1 embryos arise from the bifurcation of cell files contained in the midvein, whereas proximal branching is absent in this mutant. Restoration of this process can be achieved by increasing OCTOPUS dosage as well as by silencing RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2) expression. Although RPK2-dependent rescue of cvp2 cvl1 is auxin- and CLE peptide-independent, distal branching involves polar auxin transport and follows a distinct regulatory mechanism. Our work defines a genetic network that confers plasticity to Arabidopsis embryos to spatially adapt vascular tissues to organ growth.
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Affiliation(s)
- Elizabeth Kastanaki
- Group of Plant Vascular Development, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland
| | - Noel Blanco-Touriñán
- Group of Plant Vascular Development, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland,Authors for correspondence (; )
| | - Alexis Sarazin
- Group of RNA Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland
| | - Alessandra Sturchler
- Group of Plant Vascular Development, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland
| | - Bojan Gujas
- Group of Plant Vascular Development, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland
| | - Francisco Vera-Sirera
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas (CSIC)-Universitat Politècnica de València (UPV), 46022 Valencia, Spain
| | - Javier Agustí
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas (CSIC)-Universitat Politècnica de València (UPV), 46022 Valencia, Spain
| | - Antia Rodriguez-Villalon
- Group of Plant Vascular Development, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092 Zurich, Switzerland,Authors for correspondence (; )
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11
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Hu C, Zhu Y, Cui Y, Zeng L, Li S, Meng F, Huang S, Wang W, Kui H, Yi J, Li J, Wan D, Gou X. A CLE-BAM-CIK signalling module controls root protophloem differentiation in Arabidopsis. THE NEW PHYTOLOGIST 2022; 233:282-296. [PMID: 34651321 DOI: 10.1111/nph.17791] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 10/03/2021] [Indexed: 06/13/2023]
Abstract
Exogenous application of CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION (CLE) peptides suppresses protophloem differentiation and leads to the consumption of the proximal root meristem. However, the exact CLE peptides and the corresponding receptor complex regulating protophloem differentiation have not yet been clarified. Through expression pattern and phylogenetic analyses, CLE25/26/45 were identified as candidate peptides. Further genetic analyses, physiological assays and specific protophloem marker observations indicated that CLE25/26/45, BARELY ANY MERISTEM1/3 (BAM1/3) and CLV3 INSENSITIVE KINASEs (CIKs) are involved in regulating protophloem differentiation. The cle25 26 45 and cik2 3 4 5 6 mutation can greatly rescue the root defects of brevis radix (brx) and octopus (ops) mutants. The protophloem differentiation and proximal root meristem consumption of clv1 bam1 3 and cik2 3 4 5 6 were insensitive to CLE25/26/45 treatments. cle25 26 45, clv1 bam1 3 and cik2 3 4 5 6 displayed similar premature protophloem. In addition, CLE25/26/45 induced the interactions between BAMs and CIKs in vivo. Furthermore, CLE25/26/45 enhanced the phosphorylation levels of CIKs, which were greatly impaired in clv1 bam1 3 mutant. Our work clarifies that the CLE25/26/45-BAM1/3-CIK2/3/4/5/6 signalling module genetically acts downstream of BRX and OPS to suppress protophloem differentiation.
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Affiliation(s)
- Chong Hu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yafen Zhu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yanwei Cui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Li Zeng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Sunjingnan Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Fanhui Meng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Shuting Huang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Wenping Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Hong Kui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Jing Yi
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Dongshi Wan
- State Key Laboratory of Grassland Agro-Ecosystem, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiaoping Gou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
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12
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Chen Y, Tong S, Jiang Y, Ai F, Feng Y, Zhang J, Gong J, Qin J, Zhang Y, Zhu Y, Liu J, Ma T. Transcriptional landscape of highly lignified poplar stems at single-cell resolution. Genome Biol 2021; 22:319. [PMID: 34809675 PMCID: PMC8607660 DOI: 10.1186/s13059-021-02537-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 11/10/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Plant secondary growth depends on the activity of the vascular cambium, which produces xylem and phloem. Wood derived from xylem is the most abundant form of biomass globally and has played key socio-economic and subsistence roles throughout human history. However, despite intensive study of vascular development, the full diversity of cell types and the gene networks engaged are still poorly understood. RESULTS Here, we have applied an optimized protoplast isolation protocol and RNA sequencing to characterize the high-resolution single-cell transcriptional landscape of highly lignified poplar stems. We identify 20 putative cell clusters with a series of novel cluster-specific marker genes and find that these cells are highly heterogeneous based on the transcriptome. Analysis of these marker genes' expression dynamics enables reconstruction of the cell differentiation trajectories involved in phloem and xylem development. We find that different cell clusters exhibit distinct patterns of phytohormone responses and emphasize the use of our data to predict potential gene redundancy and identify candidate genes related to vascular development in trees. CONCLUSIONS These findings establish the transcriptional landscape of major cell types of poplar stems at single-cell resolution and provide a valuable resource for investigating basic principles of vascular cell specification and differentiation in trees.
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Affiliation(s)
- Yang Chen
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Shaofei Tong
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Yuanzhong Jiang
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Fandi Ai
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Yanlin Feng
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Junlin Zhang
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Jue Gong
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Jiajia Qin
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Yuanyuan Zhang
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Yingying Zhu
- State Key Laboratory of Grassland Agro-Ecosystem, Institute of Innovation Ecology, Lanzhou University, Lanzhou, China
| | - Jianquan Liu
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
- State Key Laboratory of Grassland Agro-Ecosystem, Institute of Innovation Ecology, Lanzhou University, Lanzhou, China
| | - Tao Ma
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China.
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13
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Graeff M, Hardtke CS. Metaphloem development in the Arabidopsis root tip. Development 2021; 148:270791. [PMID: 34224570 DOI: 10.1242/dev.199766] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/29/2021] [Indexed: 11/20/2022]
Abstract
The phloem transport network is a major evolutionary innovation that enabled plants to dominate terrestrial ecosystems. In the growth apices, the meristems, apical stem cells continuously produce early 'protophloem'. This is easily observed in Arabidopsis root meristems, in which the differentiation of individual protophloem sieve element precursors into interconnected conducting sieve tubes is laid out in a spatio-temporal gradient. The mature protophloem eventually collapses as the neighboring metaphloem takes over its function further distal from the stem cell niche. Compared with protophloem, metaphloem ontogenesis is poorly characterized, primarily because its visualization is challenging. Here, we describe the improved TetSee protocol to investigate metaphloem development in Arabidopsis root tips in combination with a set of molecular markers. We found that mature metaphloem sieve elements are only observed in the late post-meristematic root, although their specification is initiated as soon as protophloem sieve elements enucleate. Moreover, unlike protophloem sieve elements, metaphloem sieve elements only differentiate once they have fully elongated. Finally, our results suggest that metaphloem differentiation is not directly controlled by protophloem-derived cues but rather follows a distinct, robust developmental trajectory.
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Affiliation(s)
- Moritz Graeff
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, 1015 Lausanne, Switzerland
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, 1015 Lausanne, Switzerland
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14
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Koh SWH, Marhava P, Rana S, Graf A, Moret B, Bassukas AEL, Zourelidou M, Kolb M, Hammes UZ, Schwechheimer C, Hardtke CS. Mapping and engineering of auxin-induced plasma membrane dissociation in BRX family proteins. THE PLANT CELL 2021; 33:1945-1960. [PMID: 33751121 PMCID: PMC8290284 DOI: 10.1093/plcell/koab076] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/03/2021] [Indexed: 05/04/2023]
Abstract
Angiosperms have evolved the phloem for the long-distance transport of metabolites. The complex process of phloem development involves genes that only occur in vascular plant lineages. For example, in Arabidopsis thaliana, the BREVIS RADIX (BRX) gene is required for continuous root protophloem differentiation, together with PROTEIN KINASE ASSOCIATED WITH BRX (PAX). BRX and its BRX-LIKE (BRXL) homologs are composed of four highly conserved domains including the signature tandem BRX domains that are separated by variable spacers. Nevertheless, BRX family proteins have functionally diverged. For instance, BRXL2 can only partially replace BRX in the root protophloem. This divergence is reflected in physiologically relevant differences in protein behavior, such as auxin-induced plasma membrane dissociation of BRX, which is not observed for BRXL2. Here we dissected the differential functions of BRX family proteins using a set of amino acid substitutions and domain swaps. Our data suggest that the plasma membrane-associated tandem BRX domains are both necessary and sufficient to convey the biological outputs of BRX function and therefore constitute an important regulatory entity. Moreover, PAX target phosphosites in the linker between the two BRX domains mediate the auxin-induced plasma membrane dissociation. Engineering these sites into BRXL2 renders this modified protein auxin-responsive and thereby increases its biological activity in the root protophloem context.
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Affiliation(s)
- Samuel W H Koh
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, Lausanne 1015, Switzerland
| | - Petra Marhava
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, Lausanne 1015, Switzerland
| | - Surbhi Rana
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, Lausanne 1015, Switzerland
| | - Alina Graf
- Plant Systems Biology, Technical University of Munich, Freising 85354, Germany
| | - Bernard Moret
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, Lausanne 1015, Switzerland
| | | | - Melina Zourelidou
- Plant Systems Biology, Technical University of Munich, Freising 85354, Germany
| | - Martina Kolb
- Plant Systems Biology, Technical University of Munich, Freising 85354, Germany
| | - Ulrich Z Hammes
- Plant Systems Biology, Technical University of Munich, Freising 85354, Germany
| | - Claus Schwechheimer
- Plant Systems Biology, Technical University of Munich, Freising 85354, Germany
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, Lausanne 1015, Switzerland
- Author for correspondence:
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15
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Gong Y, Varnau R, Wallner E, Acharya R, Bergmann DC, Cheung LS. Quantitative and dynamic cell polarity tracking in plant cells. THE NEW PHYTOLOGIST 2021; 230:867-877. [PMID: 33378550 PMCID: PMC8048652 DOI: 10.1111/nph.17165] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/12/2020] [Indexed: 05/02/2023]
Abstract
Quantitative information on the spatiotemporal distribution of polarised proteins is central for understanding cell-fate determination, yet collecting sufficient data for statistical analysis is difficult to accomplish with manual measurements. Here we present Polarity Measurement (Pome), a semi-automated pipeline for the quantification of cell polarity and demonstrate its application to a variety of developmental contexts. Pome analysis reveals that, during asymmetric cell divisions in the Arabidopsis thaliana stomatal lineage, polarity proteins BASL and BRXL2 are more asynchronous and less mutually dependent than previously thought. A similar analysis of the linearly arrayed stomatal lineage of Brachypodium distachyon revealed that the MAPKKK BdYDA1 is segregated and polarised following asymmetrical divisions. Our results demonstrate that Pome is a versatile tool, which by itself or combined with tissue-level studies and advanced microscopy techniques can help to uncover new mechanisms of cell polarity.
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Affiliation(s)
- Yan Gong
- Department of BiologyStanford UniversityStanfordCA94305USA
| | - Rachel Varnau
- Department of BiologyStanford UniversityStanfordCA94305USA
| | | | - Raghav Acharya
- School of Chemical and Biomolecular EngineeringGeorgia Institute of TechnologyAtlantaGA30332USA
| | - Dominique C. Bergmann
- Department of BiologyStanford UniversityStanfordCA94305USA
- Howard Hughes Medical InstituteStanford UniversityStanfordCA94305USA
| | - Lily S. Cheung
- School of Chemical and Biomolecular EngineeringGeorgia Institute of TechnologyAtlantaGA30332USA
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16
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Ou Y, Kui H, Li J. Receptor-like Kinases in Root Development: Current Progress and Future Directions. MOLECULAR PLANT 2021; 14:166-185. [PMID: 33316466 DOI: 10.1016/j.molp.2020.12.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/17/2020] [Accepted: 12/09/2020] [Indexed: 05/11/2023]
Abstract
Cell-to-cell and cell-to-environment communications are critical to the growth and development of plants. Cell surface-localized receptor-like kinases (RLKs) are mainly involved in sensing various extracellular signals to initiate their corresponding cellular responses. As important vegetative organs for higher plants to adapt to a terrestrial living situation, roots play a critical role for the survival of plants. It has been demonstrated that RLKs control many biological processes during root growth and development. In this review, we summarize several key regulatory processes during Arabidopsis root development in which RLKs play critical roles. We also put forward a number of relevant questions that are required to be explored in future studies.
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Affiliation(s)
- Yang Ou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Hong Kui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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17
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Wallner ES. The value of asymmetry: how polarity proteins determine plant growth and morphology. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:5733-5739. [PMID: 32687194 PMCID: PMC7888286 DOI: 10.1093/jxb/eraa329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
Cell polarity is indispensable for forming complex multicellular organisms. Proteins that polarize at specific plasma membrane domains can either serve as scaffolds for effectors or coordinate intercellular communication and transport. Here, I give an overview of polarity protein complexes and their fundamental importance for plant development, and summarize novel mechanistic insights into their molecular networks. Examples are presented for proteins that polarize at specific plasma membrane domains to orient cell division planes, alter cell fate progression, control transport, direct cell growth, read global polarity axes, or integrate external stimuli into plant growth. The recent advances in characterizing protein polarity during plant development enable a better understanding of coordinated plant growth and open up intriguing paths that could provide a means to modulate plant morphology and adaptability in the future.
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18
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Seo M, Kim H, Lee JY. Information on the move: vascular tissue development in space and time during postembryonic root growth. CURRENT OPINION IN PLANT BIOLOGY 2020; 57:110-117. [PMID: 32905917 DOI: 10.1016/j.pbi.2020.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/08/2020] [Accepted: 08/04/2020] [Indexed: 05/27/2023]
Abstract
Cascades of temporal and spatial regulation of gene expression play crucial roles in the vascular development in plant roots. Once vascular cell fates are determined, the timing of their differentiation is tightly controlled in a cell-autonomous manner. In contrast, extensive cell-to-cell communication contributes to the positioning and specifying of vascular cell types in the root meristem. Diverse factors moving short distances in a radial direction were found to be key contributors to these processes. Furthermore, signals from differentiated phloem were found to influence the phloem precursor and determine how the corresponding asymmetric cell division proceeded. These findings highlight the potential importance of underexplored types of intercellular communication in relation to vascular tissue development during postembryonic root growth.
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Affiliation(s)
- Minji Seo
- School of Biological Sciences, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyoujin Kim
- School of Biological Sciences, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji-Young Lee
- School of Biological Sciences, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea; Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Republic of Korea.
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19
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Tichá T, Samakovli D, Kuchařová A, Vavrdová T, Šamaj J. Multifaceted roles of HEAT SHOCK PROTEIN 90 molecular chaperones in plant development. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3966-3985. [PMID: 32293686 DOI: 10.1093/jxb/eraa177] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/06/2020] [Indexed: 05/20/2023]
Abstract
HEAT SHOCK PROTEINS 90 (HSP90s) are molecular chaperones that mediate correct folding and stability of many client proteins. These chaperones act as master molecular hubs involved in multiple aspects of cellular and developmental signalling in diverse organisms. Moreover, environmental and genetic perturbations affect both HSP90s and their clients, leading to alterations of molecular networks determining respectively plant phenotypes and genotypes and contributing to a broad phenotypic plasticity. Although HSP90 interaction networks affecting the genetic basis of phenotypic variation and diversity have been thoroughly studied in animals, such studies are just starting to emerge in plants. Here, we summarize current knowledge and discuss HSP90 network functions in plant development and cellular homeostasis.
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Affiliation(s)
- Tereza Tichá
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Despina Samakovli
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Anna Kuchařová
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Tereza Vavrdová
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Jozef Šamaj
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
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20
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Receptor-like protein kinase-mediated signaling in controlling root meristem homeostasis. ABIOTECH 2020; 1:157-168. [PMID: 36303569 PMCID: PMC9590551 DOI: 10.1007/s42994-020-00024-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/09/2020] [Indexed: 02/01/2023]
Abstract
Generation of the root greatly benefits higher plants living on land. Continuous root growth and development are achieved by the root apical meristem, which acts as a reservoir of stem cells. The stem cells, on the one hand, constantly renew themselves through cell division. On the other hand, they differentiate into functional cells to form diverse tissues of the root. The balance between the maintenance and consumption of the root apical meristem is governed by cell-to-cell communications. Receptor-like protein kinases (RLKs), a group of signaling molecules localized on the cell surface, have been implicated in sensing multiple endogenous and environmental signals for plant development and stress adaptation. Over the past two decades, various RLKs and their ligands have been revealed to participate in regulating root meristem homeostasis. In this review, we focus on the recent studies about RLK-mediated signaling in regulating the maintenance and consumption of the root apical meristem.
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21
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Abstract
Cell polarity in plants operates across a broad range of spatial and temporal scales to control processes from acute cell growth to systemic hormone distribution. Similar to other eukaryotes, plants generate polarity at both the subcellular and tissue levels, often through polarization of membrane-associated protein complexes. However, likely due to the constraints imposed by the cell wall and their extremely plastic development, plants possess novel polarity molecules and mechanisms highly tuned to environmental inputs. Considerable progress has been made in identifying key plant polarity regulators, but detailed molecular understanding of polarity mechanisms remains incomplete in plants. Here, we emphasize the striking similarities in the conceptual frameworks that generate polarity in both animals and plants. To this end, we highlight how novel, plant-specific proteins engage in common themes of positive feedback, dynamic intracellular trafficking, and posttranslational regulation to establish polarity axes in development. We end with a discussion of how environmental signals control intrinsic polarity to impact postembryonic organogenesis and growth.
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Affiliation(s)
- Andrew Muroyama
- Howard Hughes Medical Institute, Stanford University, Stanford, California 94305-5020, USA; .,Department of Biology, Stanford University, Stanford, California 94305-5020, USA
| | - Dominique Bergmann
- Howard Hughes Medical Institute, Stanford University, Stanford, California 94305-5020, USA; .,Department of Biology, Stanford University, Stanford, California 94305-5020, USA
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22
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Tamaki T, Oya S, Naito M, Ozawa Y, Furuya T, Saito M, Sato M, Wakazaki M, Toyooka K, Fukuda H, Helariutta Y, Kondo Y. VISUAL-CC system uncovers the role of GSK3 as an orchestrator of vascular cell type ratio in plants. Commun Biol 2020; 3:184. [PMID: 32322004 PMCID: PMC7176705 DOI: 10.1038/s42003-020-0907-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 03/18/2020] [Indexed: 11/09/2022] Open
Abstract
The phloem transports photosynthetic assimilates and signalling molecules. It mainly consists of sieve elements (SEs), which act as "highways" for transport, and companion cells (CCs), which serve as "gates" to load/unload cargos. Though SEs and CCs function together, it remains unknown what determines the ratio of SE/CC in the phloem. Here we develop a new culture system for CC differentiation in Arabidopsis named VISUAL-CC, which almost mimics the process of the SE-CC complex formation. Comparative expression analysis in VISUAL-CC reveals that SE and CC differentiation tends to show negative correlation, while total phloem differentiation is unchanged. This varying SE/CC ratio is largely dependent on GSK3 kinase activity. Indeed, gsk3 hextuple mutants possess many more SEs and fewer CCs, whereas gsk3 gain-of-function mutants partially increase the CC number. Taken together, GSK3 activity appears to function as a cell-fate switch in the phloem, thereby balancing the SE/CC ratio.
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Affiliation(s)
- Takayuki Tamaki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Satoyo Oya
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Makiko Naito
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Yasuko Ozawa
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Tomoyuki Furuya
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan.,Department of Biology, Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Masato Saito
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Mayuko Sato
- RIKEN Centre for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Mayumi Wakazaki
- RIKEN Centre for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Kiminori Toyooka
- RIKEN Centre for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Hiroo Fukuda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Ykä Helariutta
- Institute of Biotechnology/Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Helsinki, Finland.,The Sainsbury Laboratory, University of Cambridge, Cambridge, CB2 1LR, UK
| | - Yuki Kondo
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan. .,Department of Biology, Graduate School of Science, Kobe University, Kobe, 657-8501, Japan.
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23
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Local and Systemic Effects of Brassinosteroid Perception in Developing Phloem. Curr Biol 2020; 30:1626-1638.e3. [PMID: 32220322 DOI: 10.1016/j.cub.2020.02.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/28/2020] [Accepted: 02/12/2020] [Indexed: 12/23/2022]
Abstract
The plant vasculature is an essential adaptation to terrestrial growth. Its phloem component permits efficient transfer of photosynthates between source and sink organs but also transports signals that systemically coordinate physiology and development. Here, we provide evidence that developing phloem orchestrates cellular behavior of adjacent tissues in the growth apices of plants, the meristems. Arabidopsis thaliana plants that lack the three receptor kinases BRASSINOSTEROID INSENSITIVE 1 (BRI1), BRI1-LIKE 1 (BRL1), and BRL3 ("bri3" mutants) can no longer sense brassinosteroid phytohormones and display severe dwarfism as well as patterning and differentiation defects, including disturbed phloem development. We found that, despite the ubiquitous expression of brassinosteroid receptors in growing plant tissues, exclusive expression of the BRI1 receptor in developing phloem is sufficient to systemically correct cellular growth and patterning defects that underlie the bri3 phenotype. Although this effect is brassinosteroid-dependent, it cannot be reproduced with dominant versions of known downstream effectors of BRI1 signaling and therefore possibly involves a non-canonical signaling output. Interestingly, the rescue of bri3 by phloem-specific BRI1 expression is associated with antagonism toward phloem-specific CLAVATA3/EMBRYO SURROUNDING REGION-RELATED 45 (CLE45) peptide signaling in roots. Hyperactive CLE45 signaling causes phloem sieve element differentiation defects, and consistently, knockout of CLE45 perception in bri3 background restores proper phloem development. However, bri3 dwarfism is retained in such lines. Our results thus reveal local and systemic effects of brassinosteroid perception in the phloem: whereas it locally antagonizes CLE45 signaling to permit phloem differentiation, it systemically instructs plant organ formation via a phloem-derived, non-cell-autonomous signal.
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24
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Campos R, Goff J, Rodriguez-Furlan C, Van Norman JM. The Arabidopsis Receptor Kinase IRK Is Polarized and Represses Specific Cell Divisions in Roots. Dev Cell 2020; 52:183-195.e4. [DOI: 10.1016/j.devcel.2019.12.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 09/30/2019] [Accepted: 11/25/2019] [Indexed: 01/05/2023]
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25
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Cattaneo P, Graeff M, Marhava P, Hardtke CS. Conditional effects of the epigenetic regulator JUMONJI 14 in Arabidopsis root growth. Development 2019; 146:146/23/dev183905. [PMID: 31826870 DOI: 10.1242/dev.183905] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/18/2019] [Indexed: 01/06/2023]
Abstract
Methylation of lysine 4 in histone 3 (H3K4) is a post-translational modification that promotes gene expression. H3K4 methylation can be reversed by specific demethylases with an enzymatic Jumonji C domain. In Arabidopsis thaliana, H3K4-specific JUMONJI (JMJ) proteins distinguish themselves by the association with an F/Y-rich (FYR) domain. Here, we report that jmj14 mutations partially suppress reduced root meristem size and growth vigor of brevis radix (brx) mutants. Similar to its close homologs, JMJ15, JMJ16 and JMJ18, the JMJ14 promoter confers expression in mature root vasculature. Yet, unlike jmj14, neither jmj16 nor jmj18 mutation markedly suppresses brx phenotypes. Domain-swapping experiments suggest that the specificity of JMJ14 function resides in the FYR domain. Despite JMJ14 promoter activity in the mature vasculature, jmj14 mutation affects root meristem size. However, JMJ14 protein is observed throughout the meristem, suggesting that the JMJ14 transcript region contributes substantially to the spatial aspect of JMJ14 expression. In summary, our data reveal a role for JMJ14 in root growth in sensitized genetic backgrounds that depends on its FYR domain and regulatory input from the JMJ14 cistron.
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Affiliation(s)
- Pietro Cattaneo
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Moritz Graeff
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Petra Marhava
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
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26
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Ren SC, Song XF, Chen WQ, Lu R, Lucas WJ, Liu CM. CLE25 peptide regulates phloem initiation in Arabidopsis through a CLERK-CLV2 receptor complex. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2019; 61:1043-1061. [PMID: 31127689 DOI: 10.1111/jipb.12846] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 05/24/2019] [Indexed: 05/29/2023]
Abstract
The phloem, located within the vascular system, is critical for delivery of nutrients and signaling molecules throughout the plant body. Although the morphological process and several factors regulating phloem differentiation have been reported, the molecular mechanism underlying its initiation remains largely unknown. Here, we report that the small peptide-coding gene, CLAVATA 3 (CLV3)/EMBEYO SURROUNDING REGION 25 (CLE25), the expression of which begins in provascular initial cells of 64-cell-staged embryos, and continues in sieve element-procambium stem cells and phloem lineage cells, during post-embryonic root development, facilitates phloem initiation in Arabidopsis. Knockout of CLE25 led to delayed protophloem formation, and in situ expression of an antagonistic CLE25G6T peptide compromised the fate-determining periclinal division of the sieve element precursor cell and the continuity of the phloem in roots. In stems of CLE25G6T plants the phloem formation was also compromised, and procambial cells were over-accumulated. Genetic and biochemical analyses indicated that a complex, consisting of the CLE-RESISTANT RECEPTOR KINASE (CLERK) leucine-rich repeat (LRR) receptor kinase and the CLV2 LRR receptor-like protein, is involved in perceiving the CLE25 peptide. Similar to CLE25, CLERK was also expressed during early embryogenesis. Taken together, our findings suggest that CLE25 regulates phloem initiation in Arabidopsis through a CLERK-CLV2 receptor complex.
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Affiliation(s)
- Shi-Chao Ren
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Xiu-Fen Song
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Wen-Qiang Chen
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ran Lu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - William J Lucas
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA, 95616, USA
| | - Chun-Ming Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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27
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A Cellular Insulator against CLE45 Peptide Signaling. Curr Biol 2019; 29:2501-2508.e3. [DOI: 10.1016/j.cub.2019.06.037] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/22/2019] [Accepted: 06/12/2019] [Indexed: 11/19/2022]
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28
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What Can Cell Culture Systems Reveal About Sieve Element Differentiation? Methods Mol Biol 2019. [PMID: 31197817 DOI: 10.1007/978-1-4939-9562-2_36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Tissue culture systems can be powerful tools for studying the process of cell differentiation in detail. Although a large number of cultures for xylem differentiation have been developed and utilized, there are only few reports on culture systems for ectopic phloem differentiation. Recently, a novel tissue culture system named Vascular cell Induction culture System Using Arabidopsis Leaves (VISUAL) was established, in which both xylem and phloem cells can be rapidly and efficiently induced in the model plant Arabidopsis thaliana. This chapter discusses the principle of VISUAL and how it can be used to investigate phloem differentiation, for example in combination with genetic experiments or transcriptome analysis. In addition, the protocol for establishing a phloem cell culture is provided.
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29
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Millar AH, Heazlewood JL, Giglione C, Holdsworth MJ, Bachmair A, Schulze WX. The Scope, Functions, and Dynamics of Posttranslational Protein Modifications. ANNUAL REVIEW OF PLANT BIOLOGY 2019; 70:119-151. [PMID: 30786234 DOI: 10.1146/annurev-arplant-050718-100211] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Assessing posttranslational modification (PTM) patterns within protein molecules and reading their functional implications present grand challenges for plant biology. We combine four perspectives on PTMs and their roles by considering five classes of PTMs as examples of the broader context of PTMs. These include modifications of the N terminus, glycosylation, phosphorylation, oxidation, and N-terminal and protein modifiers linked to protein degradation. We consider the spatial distribution of PTMs, the subcellular distribution of modifying enzymes, and their targets throughout the cell, and we outline the complexity of compartmentation in understanding of PTM function. We also consider PTMs temporally in the context of the lifetime of a protein molecule and the need for different PTMs for assembly, localization, function, and degradation. Finally, we consider the combined action of PTMs on the same proteins, their interactions, and the challenge ahead of integrating PTMs into an understanding of protein function in plants.
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Affiliation(s)
- A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, University of Western Australia, Crawley, Western Australia 6009, Australia;
| | - Joshua L Heazlewood
- School of BioSciences, University of Melbourne, Melbourne, Victoria 3010, Australia;
| | - Carmela Giglione
- Institute for Integrative Biology of the Cell, CNRS UMR9198, F-91198 Gif-sur-Yvette Cedex, France;
| | - Michael J Holdsworth
- School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom;
| | - Andreas Bachmair
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria;
| | - Waltraud X Schulze
- Systembiologie der Pflanze, Universität Hohenheim, 70599 Stuttgart, Germany;
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30
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Marhava P, Bassukas AEL, Zourelidou M, Kolb M, Moret B, Fastner A, Schulze WX, Cattaneo P, Hammes UZ, Schwechheimer C, Hardtke CS. A molecular rheostat adjusts auxin flux to promote root protophloem differentiation. Nature 2018; 558:297-300. [DOI: 10.1038/s41586-018-0186-z] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 04/24/2018] [Indexed: 01/30/2023]
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31
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Anne P, Hardtke CS. Phloem function and development-biophysics meets genetics. CURRENT OPINION IN PLANT BIOLOGY 2018; 43:22-28. [PMID: 29278791 DOI: 10.1016/j.pbi.2017.12.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 11/10/2017] [Accepted: 12/12/2017] [Indexed: 05/07/2023]
Abstract
Evolution of the vascular tissues allowed plants to efficiently settle land, occupy new ecological niches, and thereby crucially shape earth's biosphere. Of the two conducting cell types in the plant vasculature, the tubular network of phloem sieve elements transports phloem sap from source to sink organs. Recent years have witnessed the identification of ever more regulators of sieve element differentiation, as well as a more detailed understanding of phloem physiology and function. From molecular regulators of the commitment to sieve element fate, to enzymatic executors of the differentiation process, the toolbox to investigate sieve element formation has been greatly enlarged. To connect the various players in different genetic layers, and thus to ultimately attain a comprehensive description and understanding of sieve element development at the molecular level, appears to be within reach.
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Affiliation(s)
- Pauline Anne
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland.
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32
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Anne P, Amiguet-Vercher A, Brandt B, Kalmbach L, Geldner N, Hothorn M, Hardtke CS. CLERK is a novel receptor kinase required for sensing of root-active CLE peptides in Arabidopsis. Development 2018; 145:145/10/dev162354. [PMID: 29789310 PMCID: PMC6001375 DOI: 10.1242/dev.162354] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 04/30/2018] [Indexed: 01/21/2023]
Abstract
CLAVATA3/EMBRYO SURROUNDING REGION (CLE) peptides are secreted endogenous plant ligands that are sensed by receptor kinases (RKs) to convey environmental and developmental inputs. Typically, this involves an RK with narrow ligand specificity that signals together with a more promiscuous co-receptor. For most CLEs, biologically relevant (co-)receptors are unknown. The dimer of the receptor-like protein CLAVATA 2 (CLV2) and the pseudokinase CORYNE (CRN) conditions perception of so-called root-active CLE peptides, the exogenous application of which suppresses root growth by preventing protophloem formation in the meristem. clv2 as well as crn null mutants are resistant to root-active CLE peptides, possibly because CLV2-CRN promotes expression of their cognate receptors. Here, we have identified the CLE-RESISTANT RECEPTOR KINASE (CLERK) gene, which is required for full sensing of root-active CLE peptides in early developing protophloem. CLERK protein can be replaced by its close homologs, SENESCENCE-ASSOCIATED RECEPTOR-LIKE KINASE (SARK) and NSP-INTERACTING KINASE 1 (NIK1). Yet neither CLERK nor NIK1 ectodomains interact biochemically with described CLE receptor ectodomains. Consistently, CLERK also acts genetically independently of CLV2-CRN We, thus, have discovered a novel hub for redundant CLE sensing in the root.
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Affiliation(s)
- Pauline Anne
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Amelia Amiguet-Vercher
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Benjamin Brandt
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - Lothar Kalmbach
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Niko Geldner
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Michael Hothorn
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
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33
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Blob B, Heo JO, Helariutta Y. Phloem differentiation: an integrative model for cell specification. JOURNAL OF PLANT RESEARCH 2018; 131:31-36. [PMID: 29204753 PMCID: PMC5762813 DOI: 10.1007/s10265-017-0999-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/18/2017] [Indexed: 05/21/2023]
Abstract
Plant vasculature consists of two major conductive cell types, xylem tracheary elements and phloem sieve elements (SEs). Both cell types undergo a highly specialized differentiation process. The root meristem of Arabidopsis displays a stereotypical anatomy in which the central vasculature is surrounded by concentric layers of outer tissues. Each cell file is derived from stem cells located in the root tip. A series of formative and proliferative divisions take place in the meristem; these are followed by cell expansion and differentiation. Protophloem differentiation is unique in being complete only 20-25 cells away from the first stem cell, and during the differentiation process the cells lose several organelles, including the nucleus, while the remaining organelles are rearranged. Defects in SE development have been shown to result in impaired auxin transport and response and therefore systemically affect root growth. Although a few genes have been demonstrated to function in phloem development, detailed analyses and a comprehensive understanding of sieve element development (i.e. how often the stem cells divide, how frequently enucleation takes place, and how SE development is coordinated between cell division and differentiation on a molecular level) are still lacking. Advanced live-imaging techniques which enable prolonged time-lapse captures of root tip growth as well as single-cell transcriptomic analysis of the 20-25 cells in the SE file could help resolve these questions. In addition, understanding the interplay between the PLETHORA (PLT) gradient, which is known to govern the root zonation, and phloem development within the root meristem could shed light on the rapidity of SE differentiation and its importance to the meristem.
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Affiliation(s)
- Bernhard Blob
- Sainsbury Laboratory, Cambridge University, Bateman Street, Cambridge, CB2 1LR, UK
| | - Jung-Ok Heo
- Sainsbury Laboratory, Cambridge University, Bateman Street, Cambridge, CB2 1LR, UK
- Institute of Biotechnology, University of Helsinki, 00014, Helsinki, Finland
| | - Yka Helariutta
- Sainsbury Laboratory, Cambridge University, Bateman Street, Cambridge, CB2 1LR, UK.
- Institute of Biotechnology, University of Helsinki, 00014, Helsinki, Finland.
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34
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Kondo Y. Reconstitutive approach for investigating plant vascular development. JOURNAL OF PLANT RESEARCH 2018; 131:23-29. [PMID: 29181650 DOI: 10.1007/s10265-017-0998-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 09/10/2017] [Indexed: 06/07/2023]
Abstract
Plants generate various tissues and organs via a strictly regulated developmental program. The plant vasculature is a complex tissue system consisting of xylem and phloem tissues with a layer of cambial cells in between. Multiple regulatory steps are involved in vascular development. Although molecular and genetic studies have uncovered a variety of key factors controlling vascular development, studies of the actual functions of these factors have been limited due to the inaccessibility of the plant vasculature. Thus, to obtain a different perspective, culture systems have been widely used to analyze the sequential processes that occur during vascular development. A tissue culture system known as VISUAL, in which molecular genetic analysis can easily be performed, was recently established in Arabidopsis thaliana. This reconstitutive approach to vascular development enables this process to be investigated quickly and easily. In this review, I summarize our recent knowledge of the regulatory mechanisms underlying vascular development and provide future perspectives on vascular analyses that can be performed using VISUAL.
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Affiliation(s)
- Yuki Kondo
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1130033, Japan.
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