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Scintu D, Scacchi E, Cazzaniga F, Vinciarelli F, De Vivo M, Shtin M, Svolacchia N, Bertolotti G, Unterholzner SJ, Del Bianco M, Timmermans M, Di Mambro R, Vittorioso P, Sabatini S, Costantino P, Dello Ioio R. microRNA165 and 166 modulate response of the Arabidopsis root apical meristem to salt stress. Commun Biol 2023; 6:834. [PMID: 37567954 PMCID: PMC10421904 DOI: 10.1038/s42003-023-05201-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 08/01/2023] [Indexed: 08/13/2023] Open
Abstract
In plants, developmental plasticity allows for the modulation of organ growth in response to environmental cues. Being in contact with soil, roots are the first organ that responds to various types of soil abiotic stress such as high salt concentration. In the root, developmental plasticity relies on changes in the activity of the apical meristem, the region at the tip of the root where a set of self-renewing undifferentiated stem cells sustain growth. Here, we show that salt stress promotes differentiation of root meristem cells via reducing the dosage of the microRNAs miR165 and 166. By means of genetic, molecular and computational analysis, we show that the levels of miR165 and 166 respond to high salt concentration, and that miR165 and 166-dependent PHABULOSA (PHB) modulation is central to the response of root growth to this stress. Specifically, we show that salt-dependent reduction of miR165 and 166 causes a rapid increase in PHB expression and, hence, production of the root meristem pro-differentiation hormone cytokinin. Our data provide direct evidence for how the miRNA-dependent modulation of transcription factor dosage mediates plastic development in plants.
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Affiliation(s)
- Daria Scintu
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
- Department of Biology, University of Pisa, via L. Ghini, 13, 56126, Pisa, Italy
| | - Emanuele Scacchi
- Center for Plant Molecular Biology, University of Tübingen, Auf der Morgenstelle 32, Tübingen, 72076, Germany
| | - Francesca Cazzaniga
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Federico Vinciarelli
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Mirko De Vivo
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Margaryta Shtin
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
- Department of Biology, University of Pisa, via L. Ghini, 13, 56126, Pisa, Italy
| | - Noemi Svolacchia
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Gaia Bertolotti
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Simon Josef Unterholzner
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazzale Università, 5, 39100, Bolzano, Italy
| | | | - Marja Timmermans
- Center for Plant Molecular Biology, University of Tübingen, Auf der Morgenstelle 32, Tübingen, 72076, Germany
| | - Riccardo Di Mambro
- Department of Biology, University of Pisa, via L. Ghini, 13, 56126, Pisa, Italy
| | - Paola Vittorioso
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Sabrina Sabatini
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Paolo Costantino
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie Charles Darwin, Università di Roma, Sapienza - via dei Sardi, 70, 00185, Rome, Italy.
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2
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Shtin M, Dello Ioio R, Del Bianco M. It's Time for a Change: The Role of Gibberellin in Root Meristem Development. FRONTIERS IN PLANT SCIENCE 2022; 13:882517. [PMID: 35592570 PMCID: PMC9112047 DOI: 10.3389/fpls.2022.882517] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/14/2022] [Indexed: 05/21/2023]
Abstract
One of the most amazing characteristics of plants is their ability to grow and adapt their development to environmental changes. This fascinating feature is possible thanks to the activity of meristems, tissues that contain lasting self-renewal stem cells. Because of its simple and symmetric structure, the root meristem emerged as a potent system to uncover the developmental mechanisms behind the development of the meristems. The root meristem is formed during embryogenesis and sustains root growth for all the plant's lifetime. In the last decade, gibberellins have emerged as a key regulator for root meristem development. This phytohormone functions as a molecular clock for root development. This mini review discusses the latest advances in understanding the role of gibberellin in root development and highlights the central role of this hormone as developmental timer.
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Affiliation(s)
- Margaryta Shtin
- Department of Biology and Biotechnology “C. Darwin”, Laboratory of Functional Genomics and Proteomics of Model Systems, University of Rome “Sapienza”, Rome, Italy
| | - Raffaele Dello Ioio
- Department of Biology and Biotechnology “C. Darwin”, Laboratory of Functional Genomics and Proteomics of Model Systems, University of Rome “Sapienza”, Rome, Italy
- *Correspondence: Raffaele Dello Ioio,
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Hernández-Coronado M, Ortiz-Ramírez C. Root Patterning: Tuning SHORT ROOT Function Creates Diversity in Form. FRONTIERS IN PLANT SCIENCE 2021; 12:745861. [PMID: 34659316 PMCID: PMC8514818 DOI: 10.3389/fpls.2021.745861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
Roots have a fundamental role in plant growth and adaptation to different environments. Diversity in root morphology and architecture enables plants to acquire water and nutrients in contrasting substrate conditions, resist biotic and abiotic stress, and develop symbiotic associations. At its most fundamental level, morphology is determined by discrete changes in tissue patterning. Differences in the number and arrangement of the cell layers in the root can change tissue structure, as well as root length and girth, affecting important productivity traits. Therefore, understanding the molecular mechanisms controlling variation in developmental patterning is an important goal in biology. The ground tissue (GT) system is an ideal model to study the genetic basis of morphological diversity because it displays great interspecific variability in cell layer number. In addition, the genetic circuit controlling GT patterning in Arabidopsis thaliana has been well described, although little is known about species with more complex root anatomies. In this review, we will describe the Arabidopsis model for root radial patterning and present recent progress in elucidating the genetic circuitry controlling GT patterning in monocots and the legume Medicago truncatula (Mt), species that develop roots with more complex anatomies and multilayered cortex.
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Affiliation(s)
| | - Carlos Ortiz-Ramírez
- UGA Laboratorio Nacional de Genómica para la Biodiversidad, CINVESTAV Irapuato, Guanajuato, Mexico
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4
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Bertolotti G, Unterholzner SJ, Scintu D, Salvi E, Svolacchia N, Di Mambro R, Ruta V, Linhares Scaglia F, Vittorioso P, Sabatini S, Costantino P, Dello Ioio R. A PHABULOSA-Controlled Genetic Pathway Regulates Ground Tissue Patterning in the Arabidopsis Root. Curr Biol 2021; 31:420-426.e6. [PMID: 33176130 PMCID: PMC7846283 DOI: 10.1016/j.cub.2020.10.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 09/07/2020] [Accepted: 10/13/2020] [Indexed: 12/03/2022]
Abstract
In both animals and plants, development involves anatomical modifications. In the root of Arabidopsis thaliana, maturation of the ground tissue (GT)—a tissue comprising all cells between epidermal and vascular ones—is a paradigmatic example of these modifications, as it generates an additional tissue layer, the middle cortex (MC).1, 2, 3, 4 In early post-embryonic phases, the Arabidopsis root GT is composed of one layer of endodermis and one of cortex. A second cortex layer, the MC, is generated by asymmetric cell divisions in about 80% of Arabidopsis primary roots, in a time window spanning from 7 to 14 days post-germination (dpg). The cell cycle regulator CYCLIN D6;1 (CYCD6;1) plays a central role in this process, as its accumulation in the endodermis triggers the formation of MC.5 The phytohormone gibberellin (GA) is a key regulator of the timing of MC formation, as alterations in its signaling and homeostasis result in precocious endodermal asymmetric cell divisions.3,6,7 However, little is known on how GAs are regulated during GT maturation. Here, we show that the HOMEODOMAIN LEUCINE ZIPPER III (HD-ZIPIII) transcription factor PHABULOSA (PHB) is a master regulator of MC formation, controlling the accumulation of CYCD6;1 in the endodermis in a cell non-autonomous manner. We show that PHB activates the GA catabolic gene GIBBERELLIN 2 OXIDASE 2 (GA2ox2) in the vascular tissue, thus regulating the stability of the DELLA protein GIBBERELLIN INSENSITIVE (GAI)—a GA signaling repressor—in the root and, hence, CYCD6;1 expression in the endodermis. PHB regulates cell non-autonomously the timing of MC formation A time-dependent rise of PHB expression controls the CYCD6;1 switch in the GT PHB regulates GAI stability modulating GA levels PHB regulates root GA levels activating GA2ox2 expression in the vasculature
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Affiliation(s)
- Gaia Bertolotti
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Simon Josef Unterholzner
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazzale Università, 5, 39100 Bolzano, Italy
| | - Daria Scintu
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Elena Salvi
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Noemi Svolacchia
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Riccardo Di Mambro
- Department of Biology, University of Pisa, via L. Ghini, 13, 56126 Pisa, Italy
| | - Veronica Ruta
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | | | - Paola Vittorioso
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Sabrina Sabatini
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Paolo Costantino
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70, 00185 Rome, Italy.
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Cesarino I, Dello Ioio R, Kirschner GK, Ogden MS, Picard KL, Rast-Somssich MI, Somssich M. Plant science's next top models. ANNALS OF BOTANY 2020; 126:1-23. [PMID: 32271862 PMCID: PMC7304477 DOI: 10.1093/aob/mcaa063] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/08/2020] [Indexed: 05/05/2023]
Abstract
BACKGROUND Model organisms are at the core of life science research. Notable examples include the mouse as a model for humans, baker's yeast for eukaryotic unicellular life and simple genetics, or the enterobacteria phage λ in virology. Plant research was an exception to this rule, with researchers relying on a variety of non-model plants until the eventual adoption of Arabidopsis thaliana as primary plant model in the 1980s. This proved to be an unprecedented success, and several secondary plant models have since been established. Currently, we are experiencing another wave of expansion in the set of plant models. SCOPE Since the 2000s, new model plants have been established to study numerous aspects of plant biology, such as the evolution of land plants, grasses, invasive and parasitic plant life, adaptation to environmental challenges, and the development of morphological diversity. Concurrent with the establishment of new plant models, the advent of the 'omics' era in biology has led to a resurgence of the more complex non-model plants. With this review, we introduce some of the new and fascinating plant models, outline why they are interesting subjects to study, the questions they will help to answer, and the molecular tools that have been established and are available to researchers. CONCLUSIONS Understanding the molecular mechanisms underlying all aspects of plant biology can only be achieved with the adoption of a comprehensive set of models, each of which allows the assessment of at least one aspect of plant life. The model plants described here represent a step forward towards our goal to explore and comprehend the diversity of plant form and function. Still, several questions remain unanswered, but the constant development of novel technologies in molecular biology and bioinformatics is already paving the way for the next generation of plant models.
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Affiliation(s)
- Igor Cesarino
- Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, Butantã, São Paulo, Brazil
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Università di Roma La Sapienza, Rome, Italy
| | - Gwendolyn K Kirschner
- University of Bonn, Institute of Crop Science and Resource Conservation (INRES), Division of Crop Functional Genomics, Bonn, Germany
| | - Michael S Ogden
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Kelsey L Picard
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
| | - Madlen I Rast-Somssich
- School of Biological Sciences, Monash University, Clayton Campus, Melbourne, VIC, Australia
| | - Marc Somssich
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
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6
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Root stem cells: how to establish and maintain the eternal youth. RENDICONTI LINCEI. SCIENZE FISICHE E NATURALI 2020. [DOI: 10.1007/s12210-020-00893-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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7
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Kirbis A, Waller M, Ricca M, Bont Z, Neubauer A, Goffinet B, Szövényi P. Transcriptional Landscapes of Divergent Sporophyte Development in Two Mosses, Physcomitrium (Physcomitrella) patens and Funaria hygrometrica. FRONTIERS IN PLANT SCIENCE 2020; 11:747. [PMID: 32587596 PMCID: PMC7299128 DOI: 10.3389/fpls.2020.00747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/11/2020] [Indexed: 05/03/2023]
Abstract
Understanding the molecular basis of morphological shifts is a fundamental question of evolutionary biology. New morphologies may arise through the birth/death of genes (gene gain/loss) or by reutilizing existing gene sets. Yet, the relative contribution of these two processes to radical morphological shifts is still poorly understood. Here, we use the model system of two mosses, Funaria hygrometrica and Physcomitrium (Physcomitrella) patens, to investigate the molecular mechanisms underlying contrasting sporophyte architectures. We used comparative analysis of time-series expression data for four stages of sporophyte development in both species to address this question in detail. We found that large-scale differences in sporophytic architecture are mainly governed by orthologous (i.e., shared) genes frequently experiencing temporal gene expression shifts between the two species. While the absolute number of species-specific genes expressed during sporophyte development is somewhat smaller, we observed a significant increase of their proportion in preferentially sporophyte expressed genes, suggesting a fundamental role in the sporophyte phase. However, further functional studies are necessary to determine their contribution to diverging sporophyte morphologies. Our results add to the growing set of studies suggesting that radical changes in morphology may rely on the heterochronic expression of conserved regulators.
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Affiliation(s)
- Alexander Kirbis
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich and Zurich-Basel Plant Science Center, Zurich, Switzerland
| | - Manuel Waller
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich and Zurich-Basel Plant Science Center, Zurich, Switzerland
| | - Mariana Ricca
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Zoe Bont
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Anna Neubauer
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich and Zurich-Basel Plant Science Center, Zurich, Switzerland
| | - Bernard Goffinet
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, United States
| | - Péter Szövényi
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich and Zurich-Basel Plant Science Center, Zurich, Switzerland
- *Correspondence: Péter Szövényi,
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8
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Pierdonati E, Unterholzner SJ, Salvi E, Svolacchia N, Bertolotti G, Dello Ioio R, Sabatini S, Di Mambro R. Cytokinin-Dependent Control of GH3 Group II Family Genes in the Arabidopsis Root. PLANTS 2019; 8:plants8040094. [PMID: 30965632 PMCID: PMC6524372 DOI: 10.3390/plants8040094] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/04/2019] [Accepted: 04/06/2019] [Indexed: 01/13/2023]
Abstract
The Arabidopsis root is a dynamic system where the interaction between different plant hormones controls root meristem activity and, thus, organ growth. In the root, a characteristic graded distribution of the hormone auxin provides positional information, coordinating the proliferating and differentiating cell status. The hormone cytokinin shapes this gradient by positioning an auxin minimum in the last meristematic cells. This auxin minimum triggers a cell developmental switch necessary to start the differentiation program, thus, regulating the root meristem size. To position the auxin minimum, cytokinin promotes the expression of the IAA-amido synthase group II gene GH3.17, which conjugates auxin with amino acids, in the most external layer of the root, the lateral root cap tissue. Since additional GH3 genes are expressed in the root, we questioned whether cytokinin to position the auxin minimum also operates via different GH3 genes. Here, we show that cytokinin regulates meristem size by activating the expression of GH3.5 and GH3.6 genes, in addition to GH3.17. Thus, cytokinin activity provides a robust control of auxin activity in the entire organ necessary to regulate root growth.
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Affiliation(s)
- Emanuela Pierdonati
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Simon Josef Unterholzner
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Elena Salvi
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Noemi Svolacchia
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Gaia Bertolotti
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Sabrina Sabatini
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza-via dei Sardi, 70⁻00185 Rome, Italy.
| | - Riccardo Di Mambro
- Department of Biology, University of Pisa-via L. Ghini, 13⁻56126 Pisa, Italy.
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9
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Di Mambro R, Svolacchia N, Dello Ioio R, Pierdonati E, Salvi E, Pedrazzini E, Vitale A, Perilli S, Sozzani R, Benfey PN, Busch W, Costantino P, Sabatini S. The Lateral Root Cap Acts as an Auxin Sink that Controls Meristem Size. Curr Biol 2019; 29:1199-1205.e4. [PMID: 30880016 DOI: 10.1016/j.cub.2019.02.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 12/27/2018] [Accepted: 02/06/2019] [Indexed: 12/28/2022]
Abstract
Plant developmental plasticity relies on the activities of meristems, regions where stem cells continuously produce new cells [1]. The lateral root cap (LRC) is the outermost tissue of the root meristem [1], and it is known to play an important role during root development [2-6]. In particular, it has been shown that mechanical or genetic ablation of LRC cells affect meristem size [7, 8]; however, the molecular mechanisms involved are unknown. Root meristem size and, consequently, root growth depend on the position of the transition zone (TZ), a boundary that separates dividing from differentiating cells [9, 10]. The interaction of two phytohormones, cytokinin and auxin, is fundamental in controlling the position of the TZ [9, 10]. Cytokinin via the ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) control auxin distribution within the meristem, generating an instructive auxin minimum that positions the TZ [10]. We identify a cytokinin-dependent molecular mechanism that acts in the LRC to control the position of the TZ and meristem size. We show that auxin levels within the LRC cells depends on PIN-FORMED 5 (PIN5), a cytokinin-activated intracellular transporter that pumps auxin from the cytoplasm into the endoplasmic reticulum, and on irreversible auxin conjugation mediated by the IAA-amino synthase GRETCHEN HAGEN 3.17 (GH3.17). By titrating auxin in the LRC, the PIN5 and the GH3.17 genes control auxin levels in the entire root meristem. Overall, our results indicate that the LRC serves as an auxin sink that, under the control of cytokinin, regulates meristem size and root growth.
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Affiliation(s)
- Riccardo Di Mambro
- Department of Biology, University of Pisa - via L. Ghini, 13 - 56126 Pisa, Italy.
| | - Noemi Svolacchia
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Emanuela Pierdonati
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Elena Salvi
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Emanuela Pedrazzini
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche - Via Alfonso Corti, 12 - 20133 Milano, Italy
| | - Alessandro Vitale
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche - Via Alfonso Corti, 12 - 20133 Milano, Italy
| | - Serena Perilli
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Rosangela Sozzani
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, United States
| | - Philip N Benfey
- Department of Biology and Howard Hughes Medical Institute, Duke University, Durham, NC 27708, USA
| | - Wolfgang Busch
- Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Paolo Costantino
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy
| | - Sabrina Sabatini
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma, Sapienza - via dei Sardi, 70 - 00185 Rome, Italy.
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10
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Di Mambro R, Sabatini S, Dello Ioio R. Patterning the Axes: A Lesson from the Root. PLANTS 2018; 8:plants8010008. [PMID: 30602700 PMCID: PMC6358898 DOI: 10.3390/plants8010008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/19/2018] [Accepted: 12/24/2018] [Indexed: 12/12/2022]
Abstract
How the body plan is established and maintained in multicellular organisms is a central question in developmental biology. Thanks to its simple and symmetric structure, the root represents a powerful tool to study the molecular mechanisms underlying the establishment and maintenance of developmental axes. Plant roots show two main axes along which cells pass through different developmental stages and acquire different fates: the root proximodistal axis spans longitudinally from the hypocotyl junction (proximal) to the root tip (distal), whereas the radial axis spans transversely from the vasculature tissue (centre) to the epidermis (outer). Both axes are generated by stereotypical divisions occurring during embryogenesis and are maintained post-embryonically. Here, we review the latest scientific advances on how the correct formation of root proximodistal and radial axes is achieved.
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Affiliation(s)
- Riccardo Di Mambro
- Department of Biology, University of Pisa, via L. Ghini, 13-56126 Pisa, Italy.
| | - Sabrina Sabatini
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma "Sapienza", via dei Sardi, 70-00185 Rome, Italy.
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Laboratory of Functional Genomics and Proteomics of Model Systems, Università di Roma "Sapienza", via dei Sardi, 70-00185 Rome, Italy.
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Di Ruocco G, Di Mambro R, Dello Ioio R. Building the differences: a case for the ground tissue patterning in plants. Proc Biol Sci 2018; 285:20181746. [PMID: 30404875 PMCID: PMC6235038 DOI: 10.1098/rspb.2018.1746] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/12/2018] [Indexed: 01/03/2023] Open
Abstract
A key question in biology is to understand how interspecies morphological diversities originate. Plant roots present a huge interspecific phenotypical variability, mostly because roots largely contribute to adaptation to different kinds of soils. One example is the interspecific cortex layer number variability, spanning from one to several. Here, we review the latest advances in the understanding of the mechanisms expanding and/or restricting cortical layer number in Arabidopsis thaliana and their involvement in cortex pattern variability among multi-cortical layered species such as Cardamine hirsuta or Oryza sativa.
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Affiliation(s)
- Giovanna Di Ruocco
- Laboratory of Functional Genomics and Proteomics of Model Systems, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Via dei Sardi 70, 00185 Rome, Italy
| | - Riccardo Di Mambro
- Dipartimento di Biologia, Università di Pisa, via Luca Ghini, 13-56126 Pisa, Italy
| | - Raffaele Dello Ioio
- Laboratory of Functional Genomics and Proteomics of Model Systems, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Via dei Sardi 70, 00185 Rome, Italy
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Hofhuis HF, Heidstra R. Transcription factor dosage: more or less sufficient for growth. CURRENT OPINION IN PLANT BIOLOGY 2018; 45:50-58. [PMID: 29852330 DOI: 10.1016/j.pbi.2018.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 04/26/2018] [Accepted: 05/12/2018] [Indexed: 06/08/2023]
Abstract
Recent findings highlight three instances in which major aspects of plant development are controlled by dosage-dependent protein levels. In the shoot apical meristem the mobile transcription factor WUS displays an intricate function with respect to target regulation that involves WUS dosage, binding site affinity and protein dimerization. The size of the root meristem is controlled by dosage-dependent PLT protein activity. Recent identification of targets and feedbacks provide new insights and entry into possible mechanisms of dosage read-out. Finally, HD-ZIPIII dosage, enforced by a gradient of mobile miRNAs, presents a relatively unexplored case in the radial patterning of vasculature and ground tissue. We evaluate our current knowledge of these three examples and address molecular mechanisms of dosage translation where possible.
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Affiliation(s)
- Hugo F Hofhuis
- Department of Plant Sciences, Wageningen University Research, Netherlands
| | - Renze Heidstra
- Department of Plant Sciences, Wageningen University Research, Netherlands.
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Augstein F, Carlsbecker A. Getting to the Roots: A Developmental Genetic View of Root Anatomy and Function From Arabidopsis to Lycophytes. FRONTIERS IN PLANT SCIENCE 2018; 9:1410. [PMID: 30319672 PMCID: PMC6167918 DOI: 10.3389/fpls.2018.01410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 09/05/2018] [Indexed: 05/11/2023]
Abstract
Roots attach plants to the ground and ensure efficient and selective uptake of water and nutrients. These functions are facilitated by the morphological and anatomical structures of the root, formed by the activity of the root apical meristem (RAM) and consecutive patterning and differentiation of specific tissues with distinct functions. Despite the importance of this plant organ, its evolutionary history is not clear, but fossils suggest that roots evolved at least twice, in the lycophyte (clubmosses and their allies) and in the euphyllophyte (ferns and seed plants) lineages. Both lycophyte and euphyllophyte roots grow indeterminately by the action of an apical meristem, which is protected by a root cap. They produce root hairs, and in most species the vascular stele is guarded by a specialized endodermal cell layer. Hence, most of these traits must have evolved independently in these lineages. This raises the question if the development of these apparently analogous tissues is regulated by distinct or homologous genes, independently recruited from a common ancestor of lycophytes and euphyllophytes. Currently, there are few studies of the genetic and molecular regulation of lycophyte and fern roots. Therefore, in this review, we focus on key regulatory networks that operate in root development in the model angiosperm Arabidopsis. We describe current knowledge of the mechanisms governing RAM maintenance as well as patterning and differentiation of tissues, such as the endodermis and the vasculature, and compare with other species. We discuss the importance of comparative analyses of anatomy and morphology of extant and extinct species, along with analyses of gene regulatory networks and, ultimately, gene function in plants holding key phylogenetic positions to test hypotheses of root evolution.
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