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Schmittling SR, Muhammad D, Haque S, Long TA, Williams CM. Cellular clarity: a logistic regression approach to identify root epidermal regulators of iron deficiency response. BMC Genomics 2023; 24:620. [PMID: 37853316 PMCID: PMC10583470 DOI: 10.1186/s12864-023-09714-6] [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: 03/14/2023] [Accepted: 10/03/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Plants respond to stress through highly tuned regulatory networks. While prior works identified master regulators of iron deficiency responses in A. thaliana from whole-root data, identifying regulators that act at the cellular level is critical to a more comprehensive understanding of iron homeostasis. Within the root epidermis complex molecular mechanisms that facilitate iron reduction and uptake from the rhizosphere are known to be regulated by bHLH transcriptional regulators. However, many questions remain about the regulatory mechanisms that control these responses, and how they may integrate with developmental processes within the epidermis. Here, we use transcriptional profiling to gain insight into root epidermis-specific regulatory processes. RESULTS Set comparisons of differentially expressed genes (DEGs) between whole root and epidermis transcript measurements identified differences in magnitude and timing of organ-level vs. epidermis-specific responses. Utilizing a unique sampling method combined with a mutual information metric across time-lagged and non-time-lagged windows, we identified relationships between clusters of functionally relevant differentially expressed genes suggesting that developmental regulatory processes may act upstream of well-known Fe-specific responses. By integrating static data (DNA motif information) with time-series transcriptomic data and employing machine learning approaches, specifically logistic regression models with LASSO, we also identified putative motifs that served as crucial features for predicting differentially expressed genes. Twenty-eight transcription factors (TFs) known to bind to these motifs were not differentially expressed, indicating that these TFs may be regulated post-transcriptionally or post-translationally. Notably, many of these TFs also play a role in root development and general stress response. CONCLUSIONS This work uncovered key differences in -Fe response identified using whole root data vs. cell-specific root epidermal data. Machine learning approaches combined with additional static data identified putative regulators of -Fe response that would not have been identified solely through transcriptomic profiles and reveal how developmental and general stress responses within the epidermis may act upstream of more specialized -Fe responses for Fe uptake.
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Affiliation(s)
- Selene R Schmittling
- Department of Electrical & Computer Engineering, North Carolina State University, Raleigh, USA
| | | | - Samiul Haque
- Life Sciences Customer Advisory, SAS Institute Inc, Cary, USA
| | - Terri A Long
- Department of Plant & Microbial Biology, North Carolina State University, Raleigh, USA
| | - Cranos M Williams
- Department of Electrical & Computer Engineering, North Carolina State University, Raleigh, USA.
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Yang L, Min X, Wei Z, Liu N, Li J, Zhang Y, Yang Y. Genome-Wide Identification and Expression Analysis of the Dof Transcription Factor in Annual Alfalfa Medicago polymorpha. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091831. [PMID: 37176890 PMCID: PMC10181442 DOI: 10.3390/plants12091831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 04/20/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023]
Abstract
The Dof transcription factor is a plant-specific transcription gene family that plays various biological functions in plant development and stress response. However, no relevant research has been conducted on Medicago polymorpha. Here, 36 MpDof genes were identified in the M. polymorpha genome and further divided into 10 groups based on the comparative phylogenetic analysis. The essential information of MpDof genes, such as chromosomal localization, gene structure, conserved motifs, and selective pressures were systematically analyzed. All 36 MpDof genes were predicted to contain more cis-acting elements related to hormone response. MpDof24 and MpDof25 were predicted to interact with MpDof11 and MpDof26 to involve in the photoperiod blooms process. The MpDof genes showed a diverse expression pattern in different tissues. Notably, MpDof29 and MpDof31 were specifically expressed in the large pod and root, respectively, suggesting their crucial role in the pod and root development. qRT-PCR analysis indicated that the expression levels of MpDof10, MpDof25, MpDof26, and MpDof29 were obviously up-regulated under drought, salt, and cold stress. Collectively, genome-wide identification, evolutionary, and expression analysis of the Dof transcription gene family in M. polymorpha will provide new information to further understand and utilize the function of these Dof genes in Medicago plants.
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Affiliation(s)
- Linghua Yang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Xueyang Min
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Zhenwu Wei
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Nana Liu
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Jiaqing Li
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Youxin Zhang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
| | - Yuwei Yang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
- Institution of Grassland Science, Yangzhou University, Yangzhou 225009, China
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Li J, Zhang Y, Xu L, Wang C, Luo Y, Feng S, Yuan Y, Yang Q, Feng B. Genome-Wide Identification of DNA Binding with One Finger ( Dof) Gene Family in Tartary Buckwheat ( Fagopyrum tataricum) and Analysis of Its Expression Pattern after Exogenous Hormone Stimulation. BIOLOGY 2022; 11:biology11020173. [PMID: 35205040 PMCID: PMC8869700 DOI: 10.3390/biology11020173] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 01/11/2023]
Abstract
Simple Summary A number of studies have demonstrated that DNA binding with one finger (Dof) proteins are involved in multiple biological processes. In the present study, Dof genes or proteins in Tartary buckwheat (FtDofs) were systematically analysed, including their physical properties, phylogenetic relationships, structure, motif composition, cis-acting elements present in promoter regions, chromosomal distribution, gene duplication events, syntenic relationships, expression patterns in different tissues and different fruit developmental stages and responses to exogenous hormone stimulation. The results indicated that the expansion of FtDofs was mainly due to segmental duplication. The tissue-specific expression patterns of FtDofs and their positive responses to exogenous hormone stimulation suggest that they play important roles in the growth and development of Tartary buckwheat as well as in the adaptation to environmental changes. Collectively, this study lays a foundation for further exploration of the function of FtDof genes in Tartary buckwheat. Abstract DNA binding with one finger (Dof) proteins have been proven to be involved in multiple biological processes. However, genome-wide identification of the Dof gene family has not been reported for Tartary buckwheat (Fagopyrum tataricum). In this study, 35 FtDof proteins were identified, and they could be divided into nine phylogenetic subgroups. Proteins within the same subgroup had similar gene structure and motif composition. Moreover, abundant cis-acting elements were present in the promoter regions of FtDof genes. Segmental duplication was the primary driving force for the evolution of the FtDof gene family. Synteny analysis indicated that Tartary buckwheat was closer to dicotyledons, and more orthologous Dof genes existed among them. The expression pattern of FtDofs in different tissues and at different fruit developmental stages varied. Different tissues contained several genes that were specifically expressed. FtDof expression was mainly upregulated under methyl jasmonate treatment and downregulated under other hormone treatments. Taken together, FtDofs may play important roles in the growth and development of Tartary buckwheat and in response to abiotic and biotic stresses. Therefore, the genome-wide identification and expression pattern analysis of the Tartary buckwheat Dof gene family lays a foundation for further exploration of the functional characteristics of FtDofs in the future.
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Affiliation(s)
- Jing Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Yuchuan Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Lei Xu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Chenyang Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Yan Luo
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Shan Feng
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710129, China;
| | - Yuhao Yuan
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Qinghua Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
| | - Baili Feng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712000, China; (J.L.); (Y.Z.); (L.X.); (C.W.); (Y.L.); (Y.Y.); (Q.Y.)
- Correspondence:
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Tocci N, Gaid M, Kaftan F, Belkheir AK, Belhadj I, Liu B, Svatoš A, Hänsch R, Pasqua G, Beerhues L. Exodermis and endodermis are the sites of xanthone biosynthesis in Hypericum perforatum roots. THE NEW PHYTOLOGIST 2018; 217:1099-1112. [PMID: 29210088 DOI: 10.1111/nph.14929] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 10/20/2017] [Indexed: 05/09/2023]
Abstract
Xanthones are specialized metabolites with antimicrobial properties, which accumulate in roots of Hypericum perforatum. This medicinal plant provides widely taken remedies for depressive episodes and skin disorders. Owing to the array of pharmacological activities, xanthone derivatives attract attention for drug design. Little is known about the sites of biosynthesis and accumulation of xanthones in roots. Xanthone biosynthesis is localized at the transcript, protein, and product levels using in situ mRNA hybridization, indirect immunofluorescence detection, and high lateral and mass resolution mass spectrometry imaging (AP-SMALDI-FT-Orbitrap MSI), respectively. The carbon skeleton of xanthones is formed by benzophenone synthase (BPS), for which a cDNA was cloned from root cultures of H. perforatum var. angustifolium. Both the BPS protein and the BPS transcripts are localized to the exodermis and the endodermis of roots. The xanthone compounds as the BPS products are detected in the same tissues. The exodermis and the endodermis, which are the outermost and innermost cell layers of the root cortex, respectively, are not only highly specialized barriers for controlling the passage of water and solutes but also preformed lines of defence against soilborne pathogens and predators.
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Affiliation(s)
- Noemi Tocci
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
- Department of Environmental Biology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Mariam Gaid
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
| | - Filip Kaftan
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Asma K Belkheir
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
| | - Ines Belhadj
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
| | - Benye Liu
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
| | - Aleš Svatoš
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Robert Hänsch
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstraße 1, 38106, Braunschweig, Germany
| | - Gabriella Pasqua
- Department of Environmental Biology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Ludger Beerhues
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106, Braunschweig, Germany
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Kim CM, Han CD, Dolan L. RSL class I genes positively regulate root hair development in Oryza sativa. THE NEW PHYTOLOGIST 2017; 213:314-323. [PMID: 27716929 DOI: 10.1111/nph.14160] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/09/2016] [Indexed: 06/06/2023]
Abstract
Root hairs are filamentous protuberances from superficial cells of plant roots that are critical for nutrient uptake. Genes encoding ROOT HAIR DEFECTIVE-SIX LIKE (RSL) class I basic helix-loop-helix proteins are expressed in future root hair cells (trichoblasts) of the Arabidopsis thaliana root where they positively regulate root hair cell development. We characterized the function of class I genes in Oryza sativa root development. We show that there are three RSL class I genes in O. sativa and that each is expressed in developing root hair cells. Reduction of RSL class I function results in the development of shorter root hairs than in wild-type. Ectopic overexpression results in the development of ectopic root hair cells. These data suggest that expression of individual RSL class I proteins is sufficient for root hair development in the cereal O. sativa (rice). Therefore RSL class I genes have been conserved since O. sativa and A. thaliana last shared a common ancestor. However, given that RSL class I genes are not sufficient for root hair development in A. thaliana, it suggests that there are differences in the mechanisms repressing RSL class I gene activity between members of the Poaceae and Brassicaceae.
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Affiliation(s)
- Chul Min Kim
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, OX1 3RB, UK
- Oxford Martin School, Plants for the 21st Century Institute, University of Oxford, Oxford, OX1 3RB, UK
| | - Chang-Deok Han
- Division of Applied Life Science (BK21 Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Korea
| | - Liam Dolan
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, OX1 3RB, UK
- Oxford Martin School, Plants for the 21st Century Institute, University of Oxford, Oxford, OX1 3RB, UK
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Kim CM, Dolan L. ROOT HAIR DEFECTIVE SIX-LIKE Class I Genes Promote Root Hair Development in the Grass Brachypodium distachyon. PLoS Genet 2016; 12:e1006211. [PMID: 27494519 PMCID: PMC4975483 DOI: 10.1371/journal.pgen.1006211] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 07/05/2016] [Indexed: 11/18/2022] Open
Abstract
Genes encoding ROOT HAIR DEFECTIVE SIX-LIKE (RSL) class I basic helix loop helix proteins are expressed in future root hair cells of the Arabidopsis thaliana root meristem where they positively regulate root hair cell development. Here we show that there are three RSL class I protein coding genes in the Brachypodium distachyon genome, BdRSL1, BdRSL2 and BdRSL3, and each is expressed in developing root hair cells after the asymmetric cell division that forms root hair cells and hairless epidermal cells. Expression of BdRSL class I genes is sufficient for root hair cell development: ectopic overexpression of any of the three RSL class I genes induces the development of root hairs in every cell of the root epidermis. Expression of BdRSL class I genes in root hairless Arabidopsis thaliana root hair defective 6 (Atrhd6) Atrsl1 double mutants, devoid of RSL class I function, restores root hair development indicating that the function of these proteins has been conserved. However, neither AtRSL nor BdRSL class I genes is sufficient for root hair development in A. thaliana. These data demonstrate that the spatial pattern of class I RSL activity can account for the pattern of root hair cell differentiation in B. distachyon. However, the spatial pattern of class I RSL activity cannot account for the spatial pattern of root hair cells in A. thaliana. Taken together these data indicate that that the functions of RSL class I proteins have been conserved among most angiosperms-monocots and eudicots-despite the dramatically different patterns of root hair cell development.
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Affiliation(s)
- Chul Min Kim
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
- Oxford Martin School, University of Oxford, Oxford, United Kingdom
| | - Liam Dolan
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
- Oxford Martin School, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Zografidis A, Kapolas G, Podia V, Beri D, Papadopoulou K, Milioni D, Haralampidis K. Transcriptional regulation and functional involvement of the Arabidopsis pescadillo ortholog AtPES in root development. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 229:53-65. [PMID: 25443833 DOI: 10.1016/j.plantsci.2014.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 08/21/2014] [Indexed: 05/25/2023]
Abstract
The Pescadillo gene is highly conserved from yeasts to human and has been shown to impact on both the cell cycle and on ribosome biogenesis. However, the biological function and transcriptional regulation of the plant orthologs remain unclear. In the present study, we have implemented a combination of molecular and genetic approaches, in order to characterize the Arabidopsis thaliana pescadillo ortholog (AtPES) and its role in root development. The RNAi transgenic lines displayed severely compromised meristem structures and a reduction of the primary root length of up to 70%. The correct pattern of the cell files is distorted, whereas in the root elongation and differentiation zone the epidermal and cortex cells appear abnormally enlarged. Yeast two hybrid and BiFC experiments confirmed that AtPES interacts physically with AtPEIP1 and AtPEIP2, the orthologs of the murine Bop1 and WDR12. Promoter deletion analysis revealed that AtPES expression depends on a number of transcription factor binding sites, with the TELO-box being a crucial site for regulating its accurate tissue-specific manifestation. Our results indicate that AtPES is firmly regulated at the transcriptional level and that the corresponding protein plays a role in root developmental processes.
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Affiliation(s)
- Aris Zografidis
- University of Athens, Faculty of Biology, Department of Botany, 15784 Athens, Greece.
| | - Giorgos Kapolas
- University of Athens, Faculty of Biology, Department of Botany, 15784 Athens, Greece.
| | - Varvara Podia
- University of Athens, Faculty of Biology, Department of Botany, 15784 Athens, Greece.
| | - Despoina Beri
- University of Athens, Faculty of Biology, Department of Botany, 15784 Athens, Greece.
| | - Kalliope Papadopoulou
- University of Thessaly, Department of Biochemistry & Biotechnology, 41221 Larissa, Greece.
| | - Dimitra Milioni
- Agricultural University of Athens, Department of Agricultural Biotechnology, 11855 Athens, Greece.
| | - Kosmas Haralampidis
- University of Athens, Faculty of Biology, Department of Botany, 15784 Athens, Greece.
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Kim CM, Dolan L. Root hair development involves asymmetric cell division in Brachypodium distachyon and symmetric division in Oryza sativa. THE NEW PHYTOLOGIST 2011; 192:601-10. [PMID: 21848982 DOI: 10.1111/j.1469-8137.2011.03839.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
• The root epidermis of most angiosperms comprises hair (H) cells and nonhair (N) cells. H cells are shorter than N cells in grasses (Poaceae). • The aim of this study was to determine the developmental basis for differences in H and N cell size in the grasses Brachypodium distachyon and Oryza sativa. • We show that cytokinesis in the last cell division in each epidermal file is asymmetric in B. distachyon. The smaller daughter cell becomes an H cell and the larger cell forms an N cell. By contrast, asymmetric cytokinesis does not occur during H cell and N cell development in O. sativa and the differences in size arise because there is more cell expansion in N cells than in H cells after root hair initiation. • The different sizes of mature H and N cells result from cell division asymmetry in B. distachyon but different rates of cell expansion in O. sativa. We hypothesize that the mechanism that includes asymmetric cytokinesis during the development of H and N cells evolved among the Pooideae or ancestors of this subfamily.
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Affiliation(s)
- Chul Min Kim
- Department of Plant Sciences, University of Oxford, Oxford, UK
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Ni DA, Sozzani R, Blanchet S, Domenichini S, Reuzeau C, Cella R, Bergounioux C, Raynaud C. The Arabidopsis MCM2 gene is essential to embryo development and its over-expression alters root meristem function. THE NEW PHYTOLOGIST 2009; 184:311-322. [PMID: 19650778 DOI: 10.1111/j.1469-8137.2009.02961.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
* Minichromosome maintenance (MCM) proteins are subunits of the pre-replication complex that probably function as DNA helicases during the S phase of the cell cycle. Here, we investigated the function of AtMCM2 in Arabidopsis. * To gain an insight into the function of AtMCM2, we combined loss- and gain-of-function approaches. To this end, we analysed two null alleles of AtMCM2, and generated transgenic plants expressing AtMCM2 downstream of the constitutive 35S promoter. * Disruption of AtMCM2 is lethal at a very early stage of embryogenesis, whereas its over-expression results in reduced growth and inhibition of endoreduplication. In addition, over-expression of AtMCM2 induces the formation of additional initials in the columella root cap. In the plt1,2 mutant, defective for root apical meristem maintenance, over-expression of AtMCM2 induces lateral root initiation close to the root tip, a phenotype not reported in the wild-type or in plt1,2 mutants, even when cell cycle regulators, such as AtCYCD3;1, were over-expressed. * Taken together, our results provide evidence for the involvement of AtMCM2 in DNA replication, and suggest that it plays a crucial role in root meristem function.
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Affiliation(s)
- Di An Ni
- Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France
| | - Rosangela Sozzani
- Department of Genetics and Microbiology, University of Pavia, Via Ferrata 1, 27100 Pavia, Italy
| | - Sophie Blanchet
- Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France
| | - Séverine Domenichini
- Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France
| | - Christophe Reuzeau
- CropDesign N.V.-a BASF Plant Science Company, Technologiepark 3, B-9052 Gent, Belgium
| | - Rino Cella
- Department of Genetics and Microbiology, University of Pavia, Via Ferrata 1, 27100 Pavia, Italy
| | - Catherine Bergounioux
- Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France
| | - Cécile Raynaud
- Institut de Biotechnologie des Plantes (UMR8618), Université Paris-XI, 91405 Orsay, France
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