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Zhou F, Hu B, Li J, Yan H, Liu Q, Zeng B, Fan C. Exogenous applications of brassinosteroids promote secondary xylem differentiation in Eucalyptus grandis. PeerJ 2024; 12:e16250. [PMID: 38188140 PMCID: PMC10768668 DOI: 10.7717/peerj.16250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 09/18/2023] [Indexed: 01/09/2024] Open
Abstract
Brassinosteroids (BRs) play many pivotal roles in plant growth and development, especially in cell elongation and vascular development. Although its biosynthetic and signal transduction pathway have been well characterized in model plants, their biological roles in Eucalyptus grandis, a major hardwood tree providing fiber and energy worldwide, remain unclear. Here, we treated E. grandis plantlets with 24-epibrassinolide (EBL), the most active BR and/or BR biosynthesis inhibitor brassinazole. We recorded the plant growth and analyzed the cell structure of the root and stem with histochemical methods; then, we performed a secondary growth, BR synthesis, and signaling-related gene expression analysis. The results showed that the BRs dramatically increased the shoot length and diameter, and the exogenous BR increased the xylem area of the stem and root. In this process, EgrBRI1, EgrBZR1, and EgrBZR2 expression were induced by the BR treatment, and the expressions of HD-ZIPIII and cellulose synthase genes were also altered. To further verify the effect of BRs in secondary xylem development in Eucalyptus, we used six-month-old plants as the material and directly applied EBL to the xylem and cambium of the vertical stems. The xylem area, fiber cell length, and cell numbers showed considerable increases. Several key BR-signaling genes, secondary xylem development-related transcription factor genes, and cellulose and lignin biosynthetic genes were also considerably altered. Thus, BR had regulatory roles in secondary xylem development and differentiation via the BR-signaling pathway in this woody plant.
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Affiliation(s)
- Fangping Zhou
- Key Laboratory of State Forestry Administration on Tropical Forestry, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Bing Hu
- Key Laboratory of State Forestry Administration on Tropical Forestry, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Juan Li
- Key Laboratory of State Forestry Administration on Tropical Forestry, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Huifang Yan
- School of Life Sciences Fudan University, Shanghai, China
| | - Qianyu Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Bingshan Zeng
- Key Laboratory of State Forestry Administration on Tropical Forestry, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Chunjie Fan
- Key Laboratory of State Forestry Administration on Tropical Forestry, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
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HD-Zip III Gene Family: Identification and Expression Profiles during Leaf Vein Development in Soybean. PLANTS 2022; 11:plants11131728. [PMID: 35807680 PMCID: PMC9269512 DOI: 10.3390/plants11131728] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/16/2022] [Accepted: 06/24/2022] [Indexed: 12/14/2022]
Abstract
Leaf veins constitute the transport network for water and photosynthetic assimilates in vascular plants. The class III homeodomain-leucine zipper (HD-Zip III) gene family is central to the regulation of vascular development. In this research, we performed an overall analysis of the HD-Zip III genes in soybean (Glycine max L. Merr.). Our analysis included the phylogeny, conservation domains and cis-elements in the promoters of these genes. We used the quantitative reverse transcription-polymerase chain reaction to characterize the expression patterns of HD-Zip III genes in leaf vein development and analyze the effects of exogenous hormone treatments. In this study, twelve HD-Zip III genes were identified from the soybean genome and named. All soybean HD-Zip III proteins contained four highly conserved domains. GmHB15-L-1 transcripts showed steadily increasing accumulation during all stages of leaf vein development and were highly expressed in cambium cells. GmREV-L-1 and GmHB14-L-2 had nearly identical expression patterns in soybean leaf vein tissues. GmREV-L-1 and GmHB14-L-2 transcripts remained at stable high levels at all xylem developmental stages. GmREV-L-1 and GmHB14-L-2 were expressed at high levels in the vascular cambium and xylem cells. Overall, GmHB15-L-1 may be an essential regulator that is responsible for the formation or maintenance of soybean vein cambial cells. GmREV-L-1 and GmHB14-L-2 were correlated with xylem differentiation in soybean leaf veins. This study will pave the way for identifying the molecular mechanism of leaf vein development.
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Zhang J, Gao Y, Feng M, Cui Y, Li S, Liu L, Wang Y, Xu W, Li F. Genome-Wide Identification of the HD-ZIP III Subfamily in Upland Cotton Reveals the Involvement of GhHB8-5D in the Biosynthesis of Secondary Wall in Fiber and Drought Resistance. FRONTIERS IN PLANT SCIENCE 2022; 12:806195. [PMID: 35154197 PMCID: PMC8828970 DOI: 10.3389/fpls.2021.806195] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/20/2021] [Indexed: 05/24/2023]
Abstract
A subfamily of transcription factors known as HD-ZIP III plays distinct roles in the secondary cell wall biosynthesis, which could be attributed to the quality of cotton fiber and adaptation to drought stress. In this study, 18 HD-ZIP III genes were identified as genome wide from the upland cotton (Gossypium hirsutum). These genes are distributed on 14 different chromosomes, and all of them have undergone segmental duplications. Numerous cis-elements were identified in the promoter regions, which are related to phytohormone responses and abiotic stresses. Expression profiling of these genes by quantitative real-time (qRT)-PCR illustrated their differential spatial expression, with preferential expression in cotton fiber. Among these genes, GhHB8-5D was predicted to encode a protein that is targeted to the cell nucleus and having self-activation ability. In addition, the ectopic expression of GhHB8-5D or its synonymous mutant GhHB8-5Dm in Arabidopsis resulted in stunted plant growth, curly leaves, and twisted inflorescence stems. Microscopy examination revealed that the morphology of vascular bundles and deposition of secondary wall had substantially altered in stems, which is concomitant with the significant alteration in the transcription levels of secondary wall-related genes in these transgenic Arabidopsis. Further, ectopic expression of GhHB8-5D or GhHB8-5Dm in Arabidopsis also led to significant increase in green seedling rate and reduction in root length relative to wild type when the plants were grown under mimicked drought stress conditions. Taken together, our results may shed new light on the functional roles of GhHB8-5D that is attributable for secondary cell wall thickening in response to drought stress. Such a finding may facilitate a novel strategy for improving plant adaptations to environmental changes via regulating the biosynthesis of secondary cell wall.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Yanan Gao
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Mengru Feng
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Yuke Cui
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Shuaijie Li
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Le Liu
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Ye Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Wenliang Xu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Fuguang Li
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
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Lin W, Wang Y, Coudert Y, Kierzkowski D. Leaf Morphogenesis: Insights From the Moss Physcomitrium patens. FRONTIERS IN PLANT SCIENCE 2021; 12:736212. [PMID: 34630486 PMCID: PMC8494982 DOI: 10.3389/fpls.2021.736212] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 09/02/2021] [Indexed: 05/17/2023]
Abstract
Specialized photosynthetic organs have appeared several times independently during the evolution of land plants. Phyllids, the leaf-like organs of bryophytes such as mosses or leafy liverworts, display a simple morphology, with a small number of cells and cell types and lack typical vascular tissue which contrasts greatly with flowering plants. Despite this, the leaf structures of these two plant types share many morphological characteristics. In this review, we summarize the current understanding of leaf morphogenesis in the model moss Physcomitrium patens, focusing on the underlying cellular patterns and molecular regulatory mechanisms. We discuss this knowledge in an evolutionary context and identify parallels between moss and flowering plant leaf development. Finally, we propose potential research directions that may help to answer fundamental questions in plant development using moss leaves as a model system.
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Affiliation(s)
- Wenye Lin
- IRBV, Department of Biological Sciences, University of Montréal, Montréal, Montréal, QC, Canada
| | - Ying Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yoan Coudert
- Laboratoire Reproduction et Développement des Plantes, Ecole Normale Supérieure de Lyon, CNRS, INRA, Université Claude Bernard Lyon 1, INRIA, Lyon, France
| | - Daniel Kierzkowski
- IRBV, Department of Biological Sciences, University of Montréal, Montréal, Montréal, QC, Canada
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Xiao R, Zhang C, Guo X, Li H, Lu H. MYB Transcription Factors and Its Regulation in Secondary Cell Wall Formation and Lignin Biosynthesis during Xylem Development. Int J Mol Sci 2021; 22:3560. [PMID: 33808132 PMCID: PMC8037110 DOI: 10.3390/ijms22073560] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/26/2021] [Accepted: 03/26/2021] [Indexed: 01/12/2023] Open
Abstract
The secondary wall is the main part of wood and is composed of cellulose, xylan, lignin, and small amounts of structural proteins and enzymes. Lignin molecules can interact directly or indirectly with cellulose, xylan and other polysaccharide molecules in the cell wall, increasing the mechanical strength and hydrophobicity of plant cells and tissues and facilitating the long-distance transportation of water in plants. MYBs (v-myb avian myeloblastosis viral oncogene homolog) belong to one of the largest superfamilies of transcription factors, the members of which regulate secondary cell-wall formation by promoting/inhibiting the biosynthesis of lignin, cellulose, and xylan. Among them, MYB46 and MYB83, which comprise the second layer of the main switch of secondary cell-wall biosynthesis, coordinate upstream and downstream secondary wall synthesis-related transcription factors. In addition, MYB transcription factors other than MYB46/83, as well as noncoding RNAs, hormones, and other factors, interact with one another to regulate the biosynthesis of the secondary wall. Here, we discuss the biosynthesis of secondary wall, classification and functions of MYB transcription factors and their regulation of lignin polymerization and secondary cell-wall formation during wood formation.
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Affiliation(s)
- Ruixue Xiao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; (R.X.); (H.L.)
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; (C.Z.); (X.G.)
| | - Chong Zhang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; (C.Z.); (X.G.)
| | - Xiaorui Guo
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; (C.Z.); (X.G.)
| | - Hui Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; (R.X.); (H.L.)
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; (C.Z.); (X.G.)
| | - Hai Lu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; (R.X.); (H.L.)
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China; (C.Z.); (X.G.)
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Kaga Y, Yokoyama R, Sano R, Ohtani M, Demura T, Kuroha T, Shinohara N, Nishitani K. Interspecific Signaling Between the Parasitic Plant and the Host Plants Regulate Xylem Vessel Cell Differentiation in Haustoria of Cuscuta campestris. FRONTIERS IN PLANT SCIENCE 2020; 11:193. [PMID: 32231674 PMCID: PMC7082356 DOI: 10.3389/fpls.2020.00193] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/10/2020] [Indexed: 05/13/2023]
Abstract
The genus Cuscuta is stem parasitic angiosperms that parasitize a wide range of vascular plants via de novo formation of a distinctive parasitic organ called a haustorium. In the developing haustorium, meristematic cells, which are initiated from the stem cortical tissue, differentiate into haustorial parenchyma cells, which elongate, penetrate into the host tissues, and finally connect with the host vasculature. This interspecific vasculature connection allows the parasite to uptake water and nutrients from the host plant. Although histological aspects of haustorium development have been studied extensively, the molecular mechanisms underlying vasculature development and the interspecific connection with the host vasculature remain largely unknown. To gain insights into the interspecific cell-to-cell interactions involved in haustorium development, we established an in vitro haustorium induction system for Cuscuta campestris using Arabidopsis thaliana rosette leaves as the host plant tissue. The in vitro induction system was used to show that interaction with host tissue was required for the differentiation of parasite haustorial cells into xylem vessel cells. To further characterize the molecular events occurring during host-dependent xylem vessel cell differentiation in C. campestris, we performed a transcriptome analysis using samples from the in vitro induction system. The results showed that orthologs of genes involved in development and proliferation of vascular stem cells were up-regulated even in the absence of host tissue, whereas orthologs of genes required for xylem vessel cell differentiation were up-regulated only after some haustorial cells had elongated and contacted the host xylem. Consistent results were obtained by another transcriptome analysis of the haustorium development in C. campestris undergoing parasitization of an intact host plant. These findings suggest the involvement of host-derived signals in the regulation of non-autonomous xylem vessel differentiation and suggest that its connection to the host xylem during the haustorium development activates a set of key genes for differentiation into xylem vessel cells.
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Affiliation(s)
- Yuki Kaga
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Ryusuke Yokoyama
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Ryosuke Sano
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Japan
| | - Misato Ohtani
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Japan
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Taku Demura
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Japan
| | - Takeshi Kuroha
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Naoki Shinohara
- Faculty of Science, Kanagawa University, Hiratsuka, Kanagawa, Japan
| | - Kazuhiko Nishitani
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
- Faculty of Science, Kanagawa University, Hiratsuka, Kanagawa, Japan
- *Correspondence: Kazuhiko Nishitani,
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7
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Arreewichit P, Sae-Lim P, Nirapathpongporn K, Viboonjun U, Kongsawadworakul P, Narangajavana J. Opposite physiological effects upon jasmonic acid and brassinosteroid treatment on laticifer proliferation and co-occurrence of differential expression of genes involved in vascular development in rubber tree. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2019; 25:1283-1299. [PMID: 31564789 PMCID: PMC6745593 DOI: 10.1007/s12298-019-00686-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/18/2019] [Accepted: 06/25/2019] [Indexed: 06/10/2023]
Abstract
During growth of woody plant-trunk, the secondary meristem functions in giving rise the xylem and phloem. Rubber tree (Hevea brasiliensis Muell. Arg.), in addition, contains laticifers (latex producing vessels) in the vicinity of phloem. Insights into regulatory mechanisms of gene networks underlying laticifer proliferation in rubber tree has remained very limited. The candidate vascular development-related genes were selected to investigate for expression profile in phloem and xylem tissues of high latex yield- and high wood yield-clones of rubber tree. The differential gene expression between the mature branch-xylem and -phloem tissues was clearly observed. The cis-regulatory motif analysis revealed the existent of putative jasmonic acid (JA)- and brassinosteroid (BR)-responsive regulatory motifs in promoter regions of these genes, and consequently the effect of exogenous application of JA, BR or their respective signaling inhibitors, on the formation of laticifers in rubber tree was demonstrated. Interestingly, the laticifer numbers were significantly increased in JA-treatment, correlated with up-regulation of phloem development-related genes in both rubber tree clones. On the contrary, the laticifers were decreased in BR-treatment accompanying by up-regulation of xylem development-related genes, especially in high wood yield-rubber tree clone. BR-inhibitor treatment also enhanced laticifer numbers, while JA-inhibitor suppressed laticifer differentiation. Taken together, this study unveils the molecular interplay between JA/BR on vascular development in rubber tree and how this impacts the appearance of laticifers in this plant. This process is vital for a better understanding on laticifer differentiation and its impact in the manipulation of wood and latex yield in rubber tree improvement program.
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Affiliation(s)
- Poochita Arreewichit
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Rd., Rajthewee, Bangkok, 10400 Thailand
- Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok, Thailand
| | - Pakatorn Sae-Lim
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Rd., Rajthewee, Bangkok, 10400 Thailand
- Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok, Thailand
| | | | - Unchera Viboonjun
- Department of Plant Science, Faculty of Science, Mahidol University, Phayathai, Bangkok, Thailand
| | - Panida Kongsawadworakul
- Department of Plant Science, Faculty of Science, Mahidol University, Phayathai, Bangkok, Thailand
| | - Jarunya Narangajavana
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Rd., Rajthewee, Bangkok, 10400 Thailand
- Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok, Thailand
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8
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Etchells JP, Turner SR. Realizing pipe dreams - a detailed picture of vascular development. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1-4. [PMID: 28013229 PMCID: PMC5183087 DOI: 10.1093/jxb/erw482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- J Peter Etchells
- Department of Biosciences, Durham University, South Road, Durham DH1 3LE, UK,
| | - Simon R Turner
- Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
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9
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Rice EA, Khandelwal A, Creelman RA, Griffith C, Ahrens JE, Taylor JP, Murphy LR, Manjunath S, Thompson RL, Lingard MJ, Back SL, Larue H, Brayton BR, Burek AJ, Tiwari S, Adam L, Morrell JA, Caldo RA, Huai Q, Kouadio JLK, Kuehn R, Sant AM, Wingbermuehle WJ, Sala R, Foster M, Kinser JD, Mohanty R, Jiang D, Ziegler TE, Huang MG, Kuriakose SV, Skottke K, Repetti PP, Reuber TL, Ruff TG, Petracek ME, Loida PJ. Expression of a truncated ATHB17 protein in maize increases ear weight at silking. PLoS One 2014; 9:e94238. [PMID: 24736658 PMCID: PMC3988052 DOI: 10.1371/journal.pone.0094238] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 03/12/2014] [Indexed: 12/11/2022] Open
Abstract
ATHB17 (AT2G01430) is an Arabidopsis gene encoding a member of the α-subclass of the homeodomain leucine zipper class II (HD-Zip II) family of transcription factors. The ATHB17 monomer contains four domains common to all class II HD-Zip proteins: a putative repression domain adjacent to a homeodomain, leucine zipper, and carboxy terminal domain. However, it also possesses a unique N-terminus not present in other members of the family. In this study we demonstrate that the unique 73 amino acid N-terminus is involved in regulation of cellular localization of ATHB17. The ATHB17 protein is shown to function as a transcriptional repressor and an EAR-like motif is identified within the putative repression domain of ATHB17. Transformation of maize with an ATHB17 expression construct leads to the expression of ATHB17Δ113, a truncated protein lacking the first 113 amino acids which encodes a significant portion of the repression domain. Because ATHB17Δ113 lacks the repression domain, the protein cannot directly affect the transcription of its target genes. ATHB17Δ113 can homodimerize, form heterodimers with maize endogenous HD-Zip II proteins, and bind to target DNA sequences; thus, ATHB17Δ113 may interfere with HD-Zip II mediated transcriptional activity via a dominant negative mechanism. We provide evidence that maize HD-Zip II proteins function as transcriptional repressors and that ATHB17Δ113 relieves this HD-Zip II mediated transcriptional repression activity. Expression of ATHB17Δ113 in maize leads to increased ear size at silking and, therefore, may enhance sink potential. We hypothesize that this phenotype could be a result of modulation of endogenous HD-Zip II pathways in maize.
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Affiliation(s)
- Elena A. Rice
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Abha Khandelwal
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Robert A. Creelman
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Cara Griffith
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | | | | | - Siva Manjunath
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | | | | | - Huachun Larue
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Bonnie R. Brayton
- Dupont-Pioneer Hi-Bred International, Waipahu, Hawaii, United States of America
| | - Amanda J. Burek
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Shiv Tiwari
- Dupont-Pioneer Hi-Bred International, Hayward, California, United States of America
| | - Luc Adam
- ABCAM, Burlingame, California, United States of America
| | | | - Rico A. Caldo
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Qing Huai
- Monsanto Company, Cambridge, Massachusetts, United States of America
| | | | - Rosemarie Kuehn
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Anagha M. Sant
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Rodrigo Sala
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Matt Foster
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Josh D. Kinser
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Radha Mohanty
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Dongming Jiang
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Todd E. Ziegler
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Mingya G. Huang
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Kyle Skottke
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Peter P. Repetti
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - T. Lynne Reuber
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Thomas G. Ruff
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Paul J. Loida
- Monsanto Company, St. Louis, Missouri, United States of America
- * E-mail:
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10
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Grienenberger E, Douglas CJ. Arabidopsis VASCULAR-RELATED UNKNOWN PROTEIN1 regulates xylem development and growth by a conserved mechanism that modulates hormone signaling. PLANT PHYSIOLOGY 2014; 164:1991-2010. [PMID: 24567189 PMCID: PMC3982757 DOI: 10.1104/pp.114.236406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 02/22/2014] [Indexed: 05/17/2023]
Abstract
Despite a strict conservation of the vascular tissues in vascular plants (tracheophytes), our understanding of the genetic basis underlying the differentiation of secondary cell wall-containing cells in the xylem of tracheophytes is still far from complete. Using coexpression analysis and phylogenetic conservation across sequenced tracheophyte genomes, we identified a number of Arabidopsis (Arabidopsis thaliana) genes of unknown function whose expression is correlated with secondary cell wall deposition. Among these, the Arabidopsis VASCULAR-RELATED UNKNOWN PROTEIN1 (VUP1) gene encodes a predicted protein of 24 kD with no annotated functional domains but containing domains that are highly conserved in tracheophytes. Here, we show that the VUP1 expression pattern, determined by promoter-β-glucuronidase reporter gene expression, is associated with vascular tissues, while vup1 loss-of-function mutants exhibit collapsed morphology of xylem vessel cells. Constitutive overexpression of VUP1 caused dramatic and pleiotropic developmental defects, including severe dwarfism, dark green leaves, reduced apical dominance, and altered photomorphogenesis, resembling brassinosteroid-deficient mutants. Constitutive overexpression of VUP homologs from multiple tracheophyte species induced similar defects. Whole-genome transcriptome analysis revealed that overexpression of VUP1 represses the expression of many brassinosteroid- and auxin-responsive genes. Additionally, deletion constructs and site-directed mutagenesis were used to identify critical domains and amino acids required for VUP1 function. Altogether, our data suggest a conserved role for VUP1 in regulating secondary wall formation during vascular development by tissue- or cell-specific modulation of hormone signaling pathways.
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11
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Furuta KM, Hellmann E, Helariutta Y. Molecular control of cell specification and cell differentiation during procambial development. ANNUAL REVIEW OF PLANT BIOLOGY 2014; 65:607-38. [PMID: 24579995 DOI: 10.1146/annurev-arplant-050213-040306] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Land plants develop vascular tissues that enable the long-distance transport of water and nutrients in xylem and phloem, provide mechanical support for their vertical growth, and produce cells in radial growth. Vascular tissues are produced in many parts of the plant and during different developmental stages. Early vascular development is focused in procambial meristems, and in some species it continues during the secondary phase of plant development in cambial meristems. In this review, we highlight recent progress in understanding procambial development. This involves the analysis of stem cell-like properties of procambial tissues, specification of xylem and phloem, and differentiation of the conductive tissues. Several major plant hormones, small-RNA species, and transcriptional networks play a role in vascular development. We describe current approaches to integrating these networks as well as their potential role in explaining the diversity and evolution of plant vascular systems.
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Affiliation(s)
- Kaori Miyashima Furuta
- Institute of Biotechnology and Department of Biology and Environmental Sciences, University of Helsinki, Helsinki FIN-00014, Finland; , ,
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12
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Milhinhos A, Miguel CM. Hormone interactions in xylem development: a matter of signals. PLANT CELL REPORTS 2013; 32:867-83. [PMID: 23532297 DOI: 10.1007/s00299-013-1420-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 03/03/2013] [Accepted: 03/08/2013] [Indexed: 05/21/2023]
Abstract
Xylem provides long-distance transport of water and nutrients as well as structural support in plants. The development of the xylem tissues is modulated by several internal signals. In the last decades, the bloom of genetic and genomic tools has led to increased understanding of the molecular mechanisms underlying the function of the traditional plant hormones in xylem specification and differentiation. Critical functions have been assigned to novel signaling molecules, such as thermospermine. These signals do not function independently, but interact in a manner we are only now beginning to understand. We review the current knowledge of hormone signaling pathways and their crosstalk in cambial cell initiation and maintenance, and in xylem specification and differentiation.
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Affiliation(s)
- Ana Milhinhos
- Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal.
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13
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Miyashima S, Sebastian J, Lee JY, Helariutta Y. Stem cell function during plant vascular development. EMBO J 2012; 32:178-93. [PMID: 23169537 DOI: 10.1038/emboj.2012.301] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 10/16/2012] [Indexed: 12/17/2022] Open
Abstract
The plant vascular system, composed of xylem and phloem, evolved to connect plant organs and transport various molecules between them. During the post-embryonic growth, these conductive tissues constitutively form from cells that are derived from a lateral meristem, commonly called procambium and cambium. Procambium/cambium contains pluripotent stem cells and provides a microenvironment that maintains the stem cell population. Because vascular plants continue to form new tissues and organs throughout their life cycle, the formation and maintenance of stem cells are crucial for plant growth and development. In this decade, there has been considerable progress in understanding the molecular control of the organization and maintenance of stem cells in vascular plants. Noticeable advance has been made in elucidating the role of transcription factors and major plant hormones in stem cell maintenance and vascular tissue differentiation. These studies suggest the shared regulatory mechanisms among various types of plant stem cell pools. In this review, we focus on two aspects of stem cell function in the vascular cambium, cell proliferation and cell differentiation.
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Affiliation(s)
- Shunsuke Miyashima
- Department of Bio and Environmental Sciences, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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14
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Yamaguchi T, Nukazuka A, Tsukaya H. Leaf adaxial-abaxial polarity specification and lamina outgrowth: evolution and development. PLANT & CELL PHYSIOLOGY 2012; 53:1180-94. [PMID: 22619472 DOI: 10.1093/pcp/pcs074] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A key innovation in leaf evolution is the acquisition of a flat lamina with adaxial-abaxial polarity, which optimizes the primary function of photosynthesis. The developmental mechanism behind leaf adaxial-abaxial polarity specification and flat lamina formation has long been of interest to biologists. Surgical and genetic studies proposed a conceptual model wherein a signal derived from the shoot apical meristem is necessary for adaxial-abaxial polarity specification, and subsequent lamina outgrowth is promoted at the juxtaposition of adaxial and abaxial identities. Several distinct regulators involved in leaf adaxial-abaxial polarity specification and lamina outgrowth have been identified. Analyses of these genes demonstrated that the mutual antagonistic interactions between adaxial and abaxial determinants establish polarity and define the boundary between two domains, along which lamina outgrowth regulators function. Evolutionary developmental studies on diverse leaf forms of angiosperms proposed that alteration to the adaxial-abaxial patterning system can be a major driving force in the generation of diverse leaf forms, as represented by 'unifacial leaves', in which leaf blades have only the abaxial identity. Interestingly, unifacial leaf blades become flattened, in spite of the lack of adaxial-abaxial juxtaposition. Modification of the adaxial-abaxial patterning system is also utilized to generate complex organ morphologies, such as stamens. In this review, we summarize recent advances in the genetic mechanisms underlying leaf adaxial-abaxial polarity specification and lamina outgrowth, with emphasis on the genetic basis of the evolution and diversification of leaves.
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Affiliation(s)
- Takahiro Yamaguchi
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
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15
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Sakuma S, Salomon B, Komatsuda T. The domestication syndrome genes responsible for the major changes in plant form in the Triticeae crops. PLANT & CELL PHYSIOLOGY 2011; 52:738-49. [PMID: 21389058 PMCID: PMC3093126 DOI: 10.1093/pcp/pcr025] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The process of crop domestication began 10,000 years ago in the transition of early humans from hunter/gatherers to pastoralists/farmers. Recent research has revealed the identity of some of the main genes responsible for domestication. Two of the major domestication events in barley were (i) the failure of the spike to disarticulate and (ii) the six-rowed spike. The former mutation increased grain yield by preventing grain loss after maturity, while the latter resulted in an up to 3-fold increase in yield potential. Here we provide an overview of the disarticulation systems and inflorescence characteristics, along with the genes underlying these traits, occurring in the Triticeae tribe.
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Affiliation(s)
- Shun Sakuma
- National Institute of Agrobiological Sciences (NIAS), Plant Genome Research Unit, 2-1-2 Kan-non-dai, Tsukuba, Ibaraki, 305-8602 Japan
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo, Chiba, 271-8510 Japan
| | - Björn Salomon
- Swedish University of Agricultural Sciences, Department of Plant Breeding and Biotechnology, PO Box 101, SE-23053 Alnarp, Sweden
| | - Takao Komatsuda
- National Institute of Agrobiological Sciences (NIAS), Plant Genome Research Unit, 2-1-2 Kan-non-dai, Tsukuba, Ibaraki, 305-8602 Japan
- *Corresponding author: E-mail, ; Fax, +81-29-838-7408
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16
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Côté CL, Boileau F, Roy V, Ouellet M, Levasseur C, Morency MJ, Cooke JEK, Séguin A, MacKay JJ. Gene family structure, expression and functional analysis of HD-Zip III genes in angiosperm and gymnosperm forest trees. BMC PLANT BIOLOGY 2010; 10:273. [PMID: 21143995 PMCID: PMC3017839 DOI: 10.1186/1471-2229-10-273] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 12/11/2010] [Indexed: 05/03/2023]
Abstract
BACKGROUND Class III Homeodomain Leucine Zipper (HD-Zip III) proteins have been implicated in the regulation of cambium identity, as well as primary and secondary vascular differentiation and patterning in herbaceous plants. They have been proposed to regulate wood formation but relatively little evidence is available to validate such a role. We characterised and compared HD-Zip III gene family in an angiosperm tree, Populus spp. (poplar), and the gymnosperm Picea glauca (white spruce), representing two highly evolutionarily divergent groups. RESULTS Full-length cDNA sequences were isolated from poplar and white spruce. Phylogenetic reconstruction indicated that some of the gymnosperm sequences were derived from lineages that diverged earlier than angiosperm sequences, and seem to have been lost in angiosperm lineages. Transcript accumulation profiles were assessed by RT-qPCR on tissue panels from both species and in poplar trees in response to an inhibitor of polar auxin transport. The overall transcript profiles HD-Zip III complexes in white spruce and poplar exhibited substantial differences, reflecting their evolutionary history. Furthermore, two poplar sequences homologous to HD-Zip III genes involved in xylem development in Arabidopsis and Zinnia were over-expressed in poplar plants. PtaHB1 over-expression produced noticeable effects on petiole and primary shoot fibre development, suggesting that PtaHB1 is involved in primary xylem development. We also obtained evidence indicating that expression of PtaHB1 affected the transcriptome by altering the accumulation of 48 distinct transcripts, many of which are predicted to be involved in growth and cell wall synthesis. Most of them were down-regulated, as was the case for several of the poplar HD-Zip III sequences. No visible physiological effect of over-expression was observed on PtaHB7 transgenic trees, suggesting that PtaHB1 and PtaHB7 likely have distinct roles in tree development, which is in agreement with the functions that have been assigned to close homologs in herbaceous plants. CONCLUSIONS This study provides an overview of HD-zip III genes related to woody plant development and identifies sequences putatively involved in secondary vascular growth in angiosperms and in gymnosperms. These gene sequences are candidate regulators of wood formation and could be a source of molecular markers for tree breeding related to wood properties.
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Affiliation(s)
- Caroline L Côté
- Département des Sciences du Bois et de la Forêt, Université Laval, 2405 rue de la Terrasse, Québec, QC G1V0A6, Canada
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17
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Caño-Delgado A, Lee JY, Demura T. Regulatory Mechanisms for Specification and Patterning of Plant Vascular Tissues. Annu Rev Cell Dev Biol 2010; 26:605-37. [DOI: 10.1146/annurev-cellbio-100109-104107] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ana Caño-Delgado
- Molecular Genetics Department, Center for Research in Agricultural Genomics, Barcelona 08034, Spain;
| | - Ji-Young Lee
- Boyce Thompson Institute for Plant Research, Ithaca, NY 14853;
- Department of Plant Biology, Cornell University, Ithaca, NY 14853
| | - Taku Demura
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0136, Japan;
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18
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Kwon SI, Cho HJ, Jung JH, Yoshimoto K, Shirasu K, Park OK. The Rab GTPase RabG3b functions in autophagy and contributes to tracheary element differentiation in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 64:151-64. [PMID: 20659276 DOI: 10.1111/j.1365-313x.2010.04315.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The tracheary elements (TEs) of the xylem serve as the water-conducting vessels of the plant vascular system. To achieve this, TEs undergo secondary cell wall thickening and cell death, during which the cell contents are completely removed. Cell death of TEs is a typical example of developmental programmed cell death that has been suggested to be autophagic. However, little evidence of autophagy in TE differentiation has been provided. The present study demonstrates that the small GTP binding protein RabG3b plays a role in TE differentiation through its function in autophagy. Differentiating wild type TE cells were found to undergo autophagy in an Arabidopsis culture system. Both autophagy and TE formation were significantly stimulated by overexpression of a constitutively active mutant (RabG3bCA), and were inhibited in transgenic plants overexpressing a dominant negative mutant (RabG3bDN) or RabG3b RNAi (RabG3bRNAi), a brassinosteroid insensitive mutant bri1-301, and an autophagy mutant atg5-1. Taken together, our results suggest that autophagy occurs during TE differentiation, and that RabG3b, as a component of autophagy, regulates TE differentiation.
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Affiliation(s)
- Soon Il Kwon
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea RIKEN Plant Science Center, Yokohama 230-0045, Japan
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19
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Yoshida S, Iwamoto K, Demura T, Fukuda H. Comprehensive analysis of the regulatory roles of auxin in early transdifferentiation into xylem cells. PLANT MOLECULAR BIOLOGY 2009; 70:457-69. [PMID: 19326244 DOI: 10.1007/s11103-009-9485-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Accepted: 03/13/2009] [Indexed: 05/08/2023]
Abstract
Auxin is essential for the formation of the vascular system. We previously reported that a polar auxin transport inhibitor, 1-N-naphthylphthalamic acid (NPA) decreased intracellular auxin levels and prevented tracheary element (TE) differentiation from isolated Zinnia mesophyll cells, but that additional auxin, 1-naphthaleneacetic acid (NAA) overcame this inhibition. To understand the role of auxin in gene regulation during TE differentiation, we performed microarray analysis of genes expressed in NPA-treated cells and NPA-NAA-treated cells. The systematic gene expression analysis revealed that NAA promoted the expression of genes related to auxin signaling and transcription factors that are known to be key regulators of differentiation of procambial and xylem precursor cells. NAA also promoted the expression of genes related to biosynthesis and metabolism of other plant hormones, such as cytokinin, gibberellin and brassinosteroid. Interestingly, detailed analysis showed that NAA rapidly induces the expression of auxin carrier gene homologues. It suggested a positive feedback loop for auxin-regulating vascular differentiation. Based on these results, we discuss the auxin function in early processes of transdifferentiation into TEs.
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Affiliation(s)
- Saiko Yoshida
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
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20
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Motose H, Iwamoto K, Endo S, Demura T, Sakagami Y, Matsubayashi Y, Moore KL, Fukuda H. Involvement of phytosulfokine in the attenuation of stress response during the transdifferentiation of zinnia mesophyll cells into tracheary elements. PLANT PHYSIOLOGY 2009; 150:437-47. [PMID: 19270060 PMCID: PMC2675742 DOI: 10.1104/pp.109.135954] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Accepted: 02/25/2009] [Indexed: 05/18/2023]
Abstract
Phytosulfokine (PSK) is a sulfated peptide hormone required for the proliferation and differentiation of plant cells. Here, we characterize the physiological roles of PSK in transdifferentiation of isolated mesophyll cells of zinnia (Zinnia elegans 'Canary Bird') into tracheary elements (TEs). Transcripts for a zinnia PSK precursor gene, ZePSK1, show two peaks of expression during TE differentiation; the first accumulation is transiently induced in response to wounding at 24 h of culture, and the second accumulation is induced in the final stage of TE differentiation and is dependent on endogenous brassinosteroids. Chlorate, a potent inhibitor of peptide sulfation, is successfully applied as an inhibitor of PSK action. Chlorate significantly suppresses TE differentiation. The chlorate-induced suppression of TE differentiation is overcome by exogenously applied PSK. In the presence of chlorate, expression of stress-related genes for proteinase inhibitors and a pathogenesis-related protein is enhanced and changed from a transient to a continuous pattern. On the contrary, administration of PSK significantly reduces the accumulation of transcripts for the stress-related genes. Even in the absence of auxin and cytokinin, addition of PSK suppresses stress-related gene expression. Microarray analysis reveals 66 genes down-regulated and 42 genes up-regulated in the presence of PSK. The large majority of down-regulated genes show significant similarity to various families of stress-related proteins, including chitinases, phenylpropanoid biosynthesis enzymes, 1-aminocyclopropane-1-carboxylic acid synthase, and receptor-like protein kinases. These results suggest the involvement of PSK in the attenuation of stress response and healing of wound-activated cells during the early stage of TE differentiation.
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Affiliation(s)
- Hiroyasu Motose
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan.
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21
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Dettmer J, Elo A, Helariutta Y. Hormone interactions during vascular development. PLANT MOLECULAR BIOLOGY 2009; 69:347-60. [PMID: 18654740 DOI: 10.1007/s11103-008-9374-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Accepted: 07/01/2008] [Indexed: 05/08/2023]
Abstract
Vascular tissue in plants is unique due to its diverse and dynamic cellular patterns. Signals controlling vascular development have only recently started to emerge through biochemical, genetic, and genomic approaches in several organisms, such as Arabidopsis, Populus, and Zinnia. These signals include hormones (auxin, brassinosteroids, and cytokinins, in particular), other small regulatory molecules, their transporters, receptors, and various transcriptional regulators. In recent years it has become apparent that plant growth regulators rarely act alone, but rather their signaling pathways are interlocked in complex networks; for example, polar auxin transport (PAT) regulates vascular development during various stages and an emerging theme is its modulation by other growth regulators, depending on the developmental context. Also, several synergistic or antagonistic interactions between various growth regulators have been described. Furthermore, shoot-root interactions appear to be important for this signal integration.
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Affiliation(s)
- Jan Dettmer
- Plant Molecular Biology Laboratory, Department of Biological and Environmental Sciences, Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
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22
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Day RC, Herridge RP, Ambrose BA, Macknight RC. Transcriptome analysis of proliferating Arabidopsis endosperm reveals biological implications for the control of syncytial division, cytokinin signaling, and gene expression regulation. PLANT PHYSIOLOGY 2008; 148:1964-84. [PMID: 18923020 PMCID: PMC2593665 DOI: 10.1104/pp.108.128108] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 10/06/2008] [Indexed: 05/18/2023]
Abstract
During the early stages of seed development, Arabidopsis (Arabidopsis thaliana) endosperm is syncytial and proliferates rapidly through repeated rounds of mitosis without cytokinesis. This stage of endosperm development is important in determining final seed size and is a model for studying aspects of cellular and molecular biology, such as the cell cycle and genomic imprinting. However, the small size of the Arabidopsis seed makes high-throughput molecular analysis of the early endosperm technically difficult. Laser capture microdissection enabled high-resolution transcript analysis of the syncytial stage of Arabidopsis endosperm development at 4 d after pollination. Analysis of Gene Ontology representation revealed a developmental program dominated by the expression of genes associated with cell cycle, DNA processing, chromatin assembly, protein synthesis, cytoskeleton- and microtubule-related processes, and cell/organelle biogenesis and organization. Analysis of core cell cycle genes implicates particular gene family members as playing important roles in controlling syncytial cell division. Hormone marker analysis indicates predominance for cytokinin signaling during early endosperm development. Comparisons with publicly available microarray data revealed that approximately 800 putative early seed-specific genes were preferentially expressed in the endosperm. Early seed expression was confirmed for 71 genes using quantitative reverse transcription-polymerase chain reaction, with 27 transcription factors being confirmed as early seed specific. Promoter-reporter lines confirmed endosperm-preferred expression at 4 d after pollination for five transcription factors, which validates the approach and suggests important roles for these genes during early endosperm development. In summary, the data generated provide a useful resource providing novel insight into early seed development and identify new target genes for further characterization.
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Affiliation(s)
- Robert C Day
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
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23
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Zhou GK, Kubo M, Zhong R, Demura T, Ye ZH. Overexpression of miR165 Affects Apical Meristem Formation, Organ Polarity Establishment and Vascular Development in Arabidopsis. ACTA ACUST UNITED AC 2007; 48:391-404. [PMID: 17237362 DOI: 10.1093/pcp/pcm008] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The class III homeodomain leucine-zipper (HD-ZIP III) genes are thought to be targets of microRNAs (miRNAs) 165 and 166, but it is not known whether all the developmental processes affected by mutations of the HD-ZIP III genes could be recapitulated by an alteration in the expression of miR165 and miR166. Previous work showed that overexpression of miR166 by activation tagging results in down-regulation of the ATHB-9/PHV, ATHB-14/PHB and ATHB-15 genes, and concomitantly causes an enlargement of shoot apical meristems (SAMs) and an enhancement in vascular development. Here we demonstrated that overexpression of miR165 causes a drastic reduction in the transcript levels of all five HD-ZIP III genes in Arabidopsis. The miR165 overexpressors display prominent phenotypes reminiscent of loss-of-function mutants of rev phb phv and rev/ifl1, including loss of SAM, alteration of organ polarity, abnormal formation of carpels, inhibition of vascular development and aberrant differentiation of interfascicular fibers. Global gene expression analysis revealed a link between miR165 overexpression and altered expression of genes involved in auxin signaling and vascular development. Our results demonstrate that overexpression of miR165 recapitulates the phenotypes caused by loss-of-function mutations of HD-ZIP III genes, such as loss of SAM, altered organ polarity and defects in development of vascular tissues and interfascicular fibers.
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Affiliation(s)
- Gong-Ke Zhou
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
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24
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Demura T, Fukuda H. Transcriptional regulation in wood formation. TRENDS IN PLANT SCIENCE 2007; 12:64-70. [PMID: 17224301 DOI: 10.1016/j.tplants.2006.12.006] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 11/06/2006] [Accepted: 12/20/2006] [Indexed: 05/13/2023]
Abstract
Wood (i.e. xylem tissue) in trees is mainly composed of two types of cells, fibres and tracheary elements. Recent molecular studies of various trees, as well as the non-tree species Arabidopsis thaliana and Zinnia elegans, have revealed coordinated gene expression during differentiation of these cells in wood and the presence of several transcription factors that might govern the complex networks of transcriptional regulation. This article reviews recent findings concerning the regulation of genes by transcription factors involved in wood formation such as AUXIN RESPONSE FACTOR (ARF), CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIPIII), KANADI (KAN), MYB and NAM/ATAF/CUC (NAC).
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Affiliation(s)
- Taku Demura
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan.
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25
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Abstract
Tracheary elements (TEs) are cells in the xylem that are highly specialized for transporting water and solutes up the plant. TEs undergo a very well-defined process of differentiation that involves specification, enlargement, patterned cell wall deposition, programmed cell death and cell wall removal. This process is coordinated such that adjacent TEs are joined together to form a continuous network. Expression studies on model systems as diverse as trees and cell cultures have contributed to providing a flood of candidate genes with potential roles in TE differentiation. Analysis of some of these genes has yielded important information on processes such as patterned secondary cell wall deposition. The current challenge is to continue this functional analysis and to use these data and build an integrated model of TE development.
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Affiliation(s)
- Simon Turner
- University of Manchester, Faculty of Life Sciences, Manchester, United Kingdom.
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26
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Yamamoto R, Fujioka S, Iwamoto K, Demura T, Takatsuto S, Yoshida S, Fukuda H. Co-regulation of brassinosteroid biosynthesis-related genes during xylem cell differentiation. PLANT & CELL PHYSIOLOGY 2007; 48:74-83. [PMID: 17132633 DOI: 10.1093/pcp/pcl039] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
To understand the regulatory mechanisms of brassinosteroid (BR) biosynthesis in specific plant developmental processes, we first investigated the accumulation profiles of BRs and sterols in xylem differentiation in a Zinnia culture. The amounts of many substances in the late C28 sterol biosynthetic pathway to campesterol (CR), such as episterol and 24-methylenecholesterol, as well as those in the BR-specific biosynthetic pathway from CR to brassinolide (BL), were elevated in close association with tracheary element differentiation. Among them, 6-deoxotyphasterol (6-deoxoTY) accumulated to unusually high levels within cells cultured in tracheary element-inductive medium, while castasterone (CS) was not elevated either within or outside cells. To identify the molecular basis of this co-up-regulation of BRs and C28 sterols, we isolated Zinnia genes for the key enzymes of BR biosynthesis, ZeSTE1, ZeDIM, ZeDWF4, ZeCPD1 and ZeCPD2. RNA gel blot analysis of these genes indicated a coordinated increase in transcripts for ZeSTE1, ZeDIM, ZeDWF4 and ZeCPD1, and a tracheary element differentiation-specific increase in transcripts for ZeDWF4 and ZeCPD1. In situ hybridization experiments of ZeDWF4 and ZeCPD1 mRNAs revealed their preferential accumulation in procambium cells, immature xylem cells and xylem parenchyma cells. These results suggest that BR biosynthesis during tracheary element differentiation may be regulated by the coordinated regulation of broad sterol biosynthesis and specific regulation of BR biosynthesis, which occurs in part by elevated transcript levels of genes encoding BR biosynthetic enzymes, specifically ZeDWF4 and ZeCPD1. These data provide new insights into the regulation of BR biosynthesis and BR signaling during plant development.
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Affiliation(s)
- Ryo Yamamoto
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033 Japan.
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27
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Nagawa S, Sawa S, Sato S, Kato T, Tabata S, Fukuda H. Gene Trapping in Arabidopsis Reveals Genes Involved in Vascular Development. ACTA ACUST UNITED AC 2006; 47:1394-405. [PMID: 16980704 DOI: 10.1093/pcp/pcl009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The procambium is made up of stem cells that give rise to various vascular cells in plants. To understand the molecular nature of procambium cells, we tried to identify genes that characterize procambium cells using Arabidopsis gene trap lines. Among 26,000 gene trap lines, we found 67 lines in which beta-glucuronidase (GUS) staining occurred along vascular tissues in cotyledons and/or adult leaves. Although four gene trap lines showed procambium-preferential GUS expression, their expression patterns differed from each other during procambium development in root tips and young rosette leaves. Genomic regions flanking the gene trap insertion points in 25 of the 67 lines were determined, including three lines showing preferential GUS staining of the procambium. The three procambium-related genes encoded PINHEAD, katanin and an unknown DUF740 domain-containing protein. We discuss procambium development based on the functions and the differential GUS staining patterns of the procambium-related genes.
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Affiliation(s)
- Shingo Nagawa
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan.
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28
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Laitinen RAE, Broholm S, Albert VA, Teeri TH, Elomaa P. Patterns of MADS-box gene expression mark flower-type development in Gerbera hybrida (Asteraceae). BMC PLANT BIOLOGY 2006; 6:11. [PMID: 16762082 PMCID: PMC1525168 DOI: 10.1186/1471-2229-6-11] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Accepted: 06/09/2006] [Indexed: 05/10/2023]
Abstract
BACKGROUND The inflorescence of the cut-flower crop Gerbera hybrida (Asteraceae) consists of two principal flower types, ray and disc, which form a tightly packed head, or capitulum. Despite great interest in plant morphological evolution and the tractability of the gerbera system, very little is known regarding genetic mechanisms involved in flower type specification. Here, we provide comparative staging of ray and disc flower development and microarray screening for differentially expressed genes, accomplished via microdissection of hundreds of coordinately developing flower primordia. RESULTS Using a 9K gerbera cDNA microarray we identified a number of genes with putative specificity to individual flower types. Intrestingly, several of these encode homologs of MADS-box transcription factors otherwise known to regulate flower organ development. From these and previously obtained data, we hypothesize the functions and protein-protein interactions of several gerbera MADS-box factors. CONCLUSION Our RNA expression results suggest that flower-type specific MADS protein complexes may play a central role in differential development of ray and disc flowers across the gerbera capitulum, and that some commonality is shared with known protein functions in floral organ determination. These findings support the intriguing conjecture that the gerbera flowering head is more than a mere floral analog at the level of gene regulation.
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Affiliation(s)
- Roosa AE Laitinen
- Department of Applied Biology, P.O.Box 27, 00014 University of Helsinki, Finland
| | - Suvi Broholm
- Department of Applied Biology, P.O.Box 27, 00014 University of Helsinki, Finland
| | - Victor A Albert
- Natural History Museum, University of Oslo, P.O.Box 1172, Blindern, NO-0318 Oslo, Norway
| | - Teemu H Teeri
- Department of Applied Biology, P.O.Box 27, 00014 University of Helsinki, Finland
| | - Paula Elomaa
- Department of Applied Biology, P.O.Box 27, 00014 University of Helsinki, Finland
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Floyd SK, Zalewski CS, Bowman JL. Evolution of class III homeodomain-leucine zipper genes in streptophytes. Genetics 2006; 173:373-88. [PMID: 16489224 PMCID: PMC1461458 DOI: 10.1534/genetics.105.054239] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Accepted: 02/16/2006] [Indexed: 01/07/2023] Open
Abstract
Land plants underwent tremendous evolutionary change following the divergence of the ancestral lineage from algal relatives. Several important developmental innovations appeared as the embryophyte clade diversified, leading to the appearance of new organs and tissue types. To understand how these changes came about, we need to identify the fundamental genetic developmental programs that are responsible for growth, patterning, and differentiation and describe how these programs were modified and elaborated through time to produce novel morphologies. Class III homeodomain-leucine zipper (class III HD-Zip) genes, identified in the model plant Arabidopsis thaliana, provide good candidates for basic land plant patterning genes. We show that these genes may have evolved in a common ancestor of land plants and their algal sister group and that the gene family has diversified as land plant lineages have diversified. Phylogenetic analysis, expression data from nonflowering lineages, and evidence from Arabidopsis and other flowering plants indicate that class III HD-Zip genes acquired new functions in sporophyte apical growth, vascular patterning and differentiation, and leaf development. Modification of expression patterns that accompanied diversification of class III HD-Zip genes likely played an important role in the evolution of land plant form.
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Affiliation(s)
- Sandra K Floyd
- Section of Plant Biology, University of California, Davis, California 95616, USA
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30
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Mukherjee K, Bürglin TR. MEKHLA, a novel domain with similarity to PAS domains, is fused to plant homeodomain-leucine zipper III proteins. PLANT PHYSIOLOGY 2006; 140:1142-50. [PMID: 16607028 PMCID: PMC1435804 DOI: 10.1104/pp.105.073833] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Homeodomain (HD) proteins play important roles in the development of plants, fungi, and animals. Here we identify a novel domain, MEKHLA, in the C terminus of HD-Leu zipper (HD-ZIP) III plant HD proteins that shares similarity with a group of bacterial proteins and a protein from the green alga Chlamydomonas reinhardtii. The group of bacterial MEKHLA proteins is found in cyanobacteria and other bacteria often found associated with plants. Phylogenetic analysis suggests that a MEKHLA protein transferred, possibly from a cyanobacterium or an early chloroplast, into the nuclear genome of an early plant in a first step, and attached itself to the C terminus of an HD-ZIP IV homeobox gene in a second step. Further position-specific iterated-BLAST searches with the bacterial MEKHLA proteins revealed a subregion within the MEKHLA domain that shares significant similarity with the PAS domain. The PAS domain is a sensory module found in many proteins through all kingdoms of life. It is involved in light, oxygen, and redox potential sensation. The fact that HD-ZIP III proteins are transcription factors that have this sensory domain attached to their C terminus uncovers a potential new signaling pathway in plants.
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Affiliation(s)
- Krishanu Mukherjee
- Department of Biosciences and Nutrition and Center for Genomics and Bioinformatics, Karolinska Institutet, SE-141 57 Huddinge, Sweden
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31
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Spokevicius AV, Van Beveren KS, Bossinger G. Agrobacterium-mediated transformation of dormant lateral buds in poplar trees reveals developmental patterns in secondary stem tissues. FUNCTIONAL PLANT BIOLOGY : FPB 2006; 33:133-139. [PMID: 32689220 DOI: 10.1071/fp05176] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Accepted: 09/21/2005] [Indexed: 06/11/2023]
Abstract
In an attempt to devise a method for the rapid creation of somatic transgenic wood sectors of sufficient size that would allow us to detect and analyse altered wood characteristics within them, we have explored the manual wounding and subsequent infection with Agrobacterium of dormant lateral buds in poplar. Following treatment and transformation with a 35S-GUS construct, frequent stable transformation was found in the form of distinct and specific GUS staining patterns in the outer cortex, cambial region (including primary and secondary xylem and phloem) and pith. Sector frequency and size were consistent with anatomical features of dormant lateral buds at the time of manual wounding and Agrobacterium-infection. The suitability of somatic sector analysis for functional genomic studies as well as for studies investigating pattern formation and the developmental fate of various cell-types within poplar stems is discussed.
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Affiliation(s)
- Antanas V Spokevicius
- School of Forest and Ecosystem Science, The University of Melbourne, Water Street, Creswick, Vic. 3363, Australia
| | - Kim S Van Beveren
- School of Forest and Ecosystem Science, The University of Melbourne, Water Street, Creswick, Vic. 3363, Australia
| | - Gerd Bossinger
- School of Forest and Ecosystem Science, The University of Melbourne, Water Street, Creswick, Vic. 3363, Australia
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32
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Ko JH, Prassinos C, Han KH. Developmental and seasonal expression of PtaHB1, a Populus gene encoding a class III HD-Zip protein, is closely associated with secondary growth and inversely correlated with the level of microRNA (miR166). THE NEW PHYTOLOGIST 2006; 169:469-78. [PMID: 16411950 DOI: 10.1111/j.1469-8137.2005.01623.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In contrast to our knowledge of the shoot apical meristem, our understanding of cambium meristem differentiation and maintenance is limited. Class III homeodomain leucine-zipper (HD-Zip) proteins have been shown to play a regulatory role in vascular differentiation. The hybrid aspen (Populus tremulaxPopulus alba) class III HD-Zip transcription factor (PtaHB1) and microRNA 166 (Pta-miR166) family were cloned from hybrid aspen using a combination of in silico and polymerase chain reaction methods. Expression analyses of PtaHB1 and Pta-miR166 were performed by Northern blot analysis. The expression of PtaHB1 was closely associated with wood formation and regulated both developmentally and seasonally, with the highest expression during the active growing season. Also, its expression was inversely correlated with the level of Pta-miR166. Pta-miR166-directed cleavage of PtaHB1 in vivo was confirmed using modified 5'-rapid amplification of cDNA ends (RACE). The expression of Pta-miR166 was much higher in the winter than in the growing seasons, suggesting seasonal and developmental regulation of microRNA in this perennial plant species.
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Affiliation(s)
- Jae-Heung Ko
- Department of Forestry, Michigan State University, 126 Natural Resources, East Lansing, MI 48824-1222, USA
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33
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Yoshida S, Kuriyama H, Fukuda H. Inhibition of Transdifferentiation into Tracheary Elements by Polar Auxin Transport Inhibitors Through Intracellular Auxin Depletion. ACTA ACUST UNITED AC 2005; 46:2019-28. [PMID: 16230330 DOI: 10.1093/pcp/pci217] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Polar auxin transport is essential for the formation of continuous vascular strands in the plant body. To understand its mechanism, polar auxin transport inhibitors have often been used. However, the role of auxin in vascular differentiation at the unicellular level has remained elusive. Using a Zinnia elegans cell culture system, in which single mesophyll cells transdifferentiate into tracheary elements (TEs), we demonstrated that auxin transport inhibitors prevented TE differentiation and that high concentrations of 1-naphthaleneacetic acid (NAA) and IAA overcame the repression of TE differentiation. Measurements of NAA accumulation with 3H-labeled NAA in the presence or absence of 1-N-naphthylphthalamic acid (NPA) revealed enhanced NAA accumulation within the cell. In the NPA-treated cells, intracellular free NAA decreased, while its metabolites increased. Therefore, the polar auxin transport inhibitors may prevent auxin efflux and consequently promote NAA accumulation in Zinnia cells. The excess intracellular NAA may also activate NAA metabolism, resulting in a decrease in free NAA levels. This depletion of free NAA may prevent TE differentiation. The decreased auxin activity in NPA-treated cells was confirmed by the fact that the DR5 (a synthetic auxin-inducible promoter)-mediated expression of a reporter protein was suppressed in such cells. Gene expression analysis indicated that NPA suppressed TE differentiation at an early process of transdifferentiation into TEs. Based on these results, the inter-relationship between auxin and vascular cell development at a cellular level is discussed.
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Affiliation(s)
- Saiko Yoshida
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
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34
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Carlsbecker A, Helariutta Y. Phloem and xylem specification: pieces of the puzzle emerge. CURRENT OPINION IN PLANT BIOLOGY 2005; 8:512-7. [PMID: 16039153 DOI: 10.1016/j.pbi.2005.07.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Accepted: 07/12/2005] [Indexed: 05/03/2023]
Abstract
The plant vascular system is composed of two tissue types, xylem and phloem, which originate from the vascular meristem, the procambium. Recently, several regulatory mechanisms that control the specification of these two tissue types have been uncovered. These include the asymmetric patterning of xylem and phloem in the vascular bundle by the class III HD-ZIP and KANADI genes, the tissue-type-specific control of vascular cell proliferation by brassinosteroids and class III HD-ZIP genes, the regulation of vascular tissue identity by the MYB-like transcription factor APL, and inductive signalling during xylem differentiation by xylogen. These findings define an emerging developmental framework for the control of vascular tissue specification.
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Affiliation(s)
- Annelie Carlsbecker
- Institute of Biotechnology, Viikinkaari 4, FI-00014 University of Helsinki, Finland
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35
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Ohashi-Ito K, Kubo M, Demura T, Fukuda H. Class III homeodomain leucine-zipper proteins regulate xylem cell differentiation. PLANT & CELL PHYSIOLOGY 2005; 46:1646-56. [PMID: 16081527 DOI: 10.1093/pcp/pci180] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Although it has been suggested that class III homeodomain leucine-zipper proteins (HD-Zip III) are involved in vascular development, details of the function of individual HD-Zip III proteins in vascular differentiation have not been resolved. To understand the function of each HD-Zip III protein in vascular differentiation precisely, we analyzed the in vitro transcriptional activity and in vivo function of Zinnia HD-Zip III genes, ZeHB-10, ZeHB-11 and ZeHB-12, which show xylem-related expression. Transgenic Arabidopsis plants harboring cauliflower mosaic virus 35S-driven ZeHB-10 and ZeHB-12 with a mutation in the START domain (mtZeHB-10, mtZeHB-12) showed a higher production of tracheary elements (TEs) and xylem precursor cells, respectively. A systematic analysis with Genechip arrays revealed that overexpression of mtZeHB-12 rapidly induced various genes, including brassinosteroid-signaling pathway-related genes and genes for transcription factors that are expressed specifically in vascular tissues in situ. Furthermore, mtZeHB-12 overexpression did not induce TE-specific genes, including genes related to programmed cell death and lignin polymerization, but did induce lignin monomer synthesis-related genes, which are expressed in xylem parenchyma cells. These results suggest that ZeHB-12 is involved in the differentiation of xylem parenchyma cells, but not of TEs.
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Affiliation(s)
- Kyoko Ohashi-Ito
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Japan.
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36
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Prassinos C, Ko JH, Yang J, Han KH. Transcriptome profiling of vertical stem segments provides insights into the genetic regulation of secondary growth in hybrid aspen trees. PLANT & CELL PHYSIOLOGY 2005; 46:1213-25. [PMID: 15908438 DOI: 10.1093/pcp/pci130] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
In order to better understand the genetic regulation of secondary growth in hybrid aspen (Populus tremula L.xP. alba L.), we carried out a series of cDNA-amplified fragment length polymorphism (AFLP)-based transcriptome analyses in vertical stem segments that represent a gradient of developmental stages with regard to secondary growth. This approach allowed us to screen >80% of the transcriptome expressed in six samples and identify genes differentially expressed with the progress of secondary growth, in a tissue-specific manner. Of the 76,800 transcript-derived fragments (TDFs) analyzed, 271 TDFs were selected and sequenced based on their differential expression patterns. Many of the xylem-up-regulated genes were involved in cell wall and lignin biosynthesis, while the bark-up-regulated genes had diverse functional roles. About 25% of the xylem-up-regulated TDFs analyzed were involved in the phenylpropanoid biosynthesis pathway, which produces the cell wall polymer lignin and various wood extractives. In addition, many of the TDFs showing secondary xylem-specific expression were annotated as genes not previously reported in Populus, including novel cell death proteins, cytoskeleton-interacting proteins, transporters and putative transcription factors.
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Affiliation(s)
- Constantinos Prassinos
- Department of Forestry, Michigan State University, 126 Natural Resources, East Lansing, MI 48824-1222, USA
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37
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Scarpella E, Simons EJ, Meijer AH. Multiple regulatory elements contribute to the vascular-specific expression of the rice HD-Zip gene Oshox1 in Arabidopsis. PLANT & CELL PHYSIOLOGY 2005; 46:1400-10. [PMID: 15964905 DOI: 10.1093/pcp/pci153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The primary vascular tissues of plants differentiate from a single precursor tissue, the procambium. The role of upstream regulatory sequences in the transcriptional control of early vascular-specific gene expression is largely unknown. The onset of expression of the rice homeodomain-leucine zipper (HD-Zip) gene Oshox1 marks procambial cells that have acquired their distinctive anatomical features but do not yet display any overt signs of terminal vascular differentiation. The expression pattern of Oshox1 in rice appears to be mainly controlled by the activity of the 1.6 kb upstream promoter region. Here, we show that the Oshox1 promoter directs vascular, auxin- and sucrose-responsive reporter gene expression in Arabidopsis plants in a fashion comparable with that in rice. This is the case not only during normal development but also upon experimental manipulation, suggesting that the cis-acting regulatory elements that are instrumental in Oshox1 expression pattern are conserved between rice and Arabidopsis. Finally, through analysis of reporter gene expression profiles conferred by progressive 5' deletions of the Oshox1 promoter in transgenic Arabidopsis, we have identified upstream regulatory regions required for auxin and sucrose inducibility, and for cell type-, tissue- and organ-specific aspects of Oshox1 expression. Our study suggests that Oshox1 embryonic vascular expression is mainly achieved through suppression of expression in non-vascular tissues.
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Affiliation(s)
- Enrico Scarpella
- Insitute of Biology, Leiden University, Clusius Laboratory, Wassenaarseweg 64, 2333 AL Leiden, The Netherlands
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38
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Dahiya P, Milioni D, Wells B, Stacey N, Roberts K, McCann MC. A RING domain gene is expressed in different cell types of leaf trace, stem, and juvenile bundles in the stem vascular system of zinnia. PLANT PHYSIOLOGY 2005; 138:1383-95. [PMID: 15965022 PMCID: PMC1176411 DOI: 10.1104/pp.104.057901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The in vitro zinnia (Zinnia elegans) mesophyll cell system, in which leaf mesophyll cells are induced to transdifferentiate into tracheary elements with high synchrony, has become an established model for studying xylogenesis. The architecture of the stem vascular system of zinnia cv Envy contains three anatomically distinct vascular bundles at different stages of development. Juvenile vascular strands of the subapical region develop into mature vascular strands with leaf trace segments and stem segments. Characteristic patterns of gene expression in juvenile, leaf trace, and stem bundles are revealed by a molecular marker, a RING domain-encoding gene, ZeRH2.1, originally isolated from a zinnia cDNA library derived from differentiating in vitro cultures. Using RNA in situ hybridization, we show that ZeRH2.1 is expressed preferentially in two specific cell types in mature zinnia stems. In leaf trace bundles, ZeRH2.1 transcript is abundant in xylem parenchyma cells, while in stem bundles it is abundant in phloem companion cells. Both of these cell types show wall ingrowths characteristic of transfer cells. In addition, ZeRH2.1 transcript is abundant in some phloem cells of juvenile bundles and in leaf palisade parenchyma. The complex and developmentally regulated expression pattern of ZeRH2.1 reveals heterogeneity in the vascular anatomy of the zinnia stem. We discuss a potential function for this gene in intercellular transport processes.
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Affiliation(s)
- Preeti Dahiya
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
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39
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Kim J, Jung JH, Reyes JL, Kim YS, Kim SY, Chung KS, Kim JA, Lee M, Lee Y, Kim VN, Chua NH, Park CM. microRNA-directed cleavage of ATHB15 mRNA regulates vascular development in Arabidopsis inflorescence stems. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2005; 42:84-94. [PMID: 15773855 PMCID: PMC1382282 DOI: 10.1111/j.1365-313x.2005.02354.x] [Citation(s) in RCA: 243] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Class III homeodomain-leucine zipper proteins regulate critical aspects of plant development, including lateral organ polarity, apical and lateral meristem formation, and vascular development. ATHB15, a member of this transcription factor family, is exclusively expressed in vascular tissues. Recently, a microRNA (miRNA) binding sequence has been identified in ATHB15 mRNA, suggesting that a molecular mechanism governed by miRNA binding may direct vascular development through ATHB15. Here, we show that miR166-mediated ATHB15 mRNA cleavage is a principal mechanism for the regulation of vascular development. In a gain-of-function MIR166a mutant, the decreased transcript level of ATHB15 was accompanied by an altered vascular system with expanded xylem tissue and interfascicular region, indicative of accelerated vascular cell differentiation from cambial/procambial cells. A similar phenotype was observed in Arabidopsis plants with reduced ATHB15 expression but reversed in transgenic plants overexpressing an miR166-resistant ATHB15. ATHB15 mRNA cleavage occurred in standard wheat germ extracts and in Arabidopsis and was mediated by miR166 in Nicotiana benthamiana cells. miR166-assisted ATHB15 repression is likely to be a conserved mechanism that regulates vascular development in all vascular plants.
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Affiliation(s)
- Joonki Kim
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Jae-Hoon Jung
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Jose L. Reyes
- Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-3699, USA, and
| | - Youn-Sung Kim
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Sun-Young Kim
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Kyung-Sook Chung
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Jin A. Kim
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Minsun Lee
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
| | - Yoontae Lee
- School of Biological Sciences, Seoul National University, Seoul, 151-742, South Korea
| | - V. Narry Kim
- School of Biological Sciences, Seoul National University, Seoul, 151-742, South Korea
| | - Nam-Hai Chua
- Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-3699, USA, and
| | - Chung-Mo Park
- Graduate School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, South Korea
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40
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Prigge MJ, Otsuga D, Alonso JM, Ecker JR, Drews GN, Clark SE. Class III homeodomain-leucine zipper gene family members have overlapping, antagonistic, and distinct roles in Arabidopsis development. THE PLANT CELL 2005; 17:61-76. [PMID: 15598805 PMCID: PMC544490 DOI: 10.1105/tpc.104.026161] [Citation(s) in RCA: 514] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2004] [Accepted: 10/10/2004] [Indexed: 05/18/2023]
Abstract
The Arabidopsis thaliana genome contains five class III homeodomain-leucine zipper genes. We have isolated loss-of-function alleles for each family member for use in genetic analysis. This gene family regulates apical embryo patterning, embryonic shoot meristem formation, organ polarity, vascular development, and meristem function. Genetic analyses revealed a complex pattern of overlapping functions, some of which are not readily inferred by phylogenetic relationships or by gene expression patterns. The PHABULOSA and PHAVOLUTA genes perform overlapping functions with REVOLUTA, whereas the PHABULOSA, PHAVOLUTA, and CORONA/ATHB15 genes perform overlapping functions distinct from REVOLUTA. Furthermore, ATHB8 and CORONA encode functions that are both antagonistic to those of REVOLUTA within certain tissues and overlapping with REVOLUTA in other tissues. Differences in expression patterns explain some of these genetic interactions, whereas other interactions are likely attributable to differences in protein function as indicated by cross-complementation studies.
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Affiliation(s)
- Michael J Prigge
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, An Arbor, Michigan 48109-1048, USA
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41
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Scarpella E, Meijer AH. Pattern formation in the vascular system of monocot and dicot plant species. THE NEW PHYTOLOGIST 2004; 164:209-242. [PMID: 33873557 DOI: 10.1111/j.1469-8137.2004.01191.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Plant vascular tissues are organised in continuous strands, the longitudinal and radial patterns of which are intimately linked to the signals that direct plant architecture as a whole. Therefore, understanding the mechanisms underlying vascular tissue patterning is expected to shed light on patterning events beyond those that organise the vascular system, and thus represents a central issue in plant developmental biology. A number of recent advances, reviewed here, are leading to a more precise definition of the signals that control the formation of vascular tissues and their integration into a larger organismal context. Contents Summary 209 I. Introduction 209 II. The plant vascular system 210 III. Ontogeny of the vascular tissues 210 IV. Procambium development 210 V. The organisation of the vascular tissues 212 VI. The regulation of longitudinal vascular pattern formation 214 VII. The regulation of radial vascular pattern formation 220 VIII. Genetic screens for vascular development mutants 231 IX. Genes involved in vascular development identified through reverse genetics approaches 235 X. Conclusions and perspectives 235 Note added at the revision stage 236 Acknowledgements 236 References 236.
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Affiliation(s)
- Enrico Scarpella
- Department of Botany, University of Toronto, 25 Willcocks Street, Toronto ON, Canada M5S 3B2
- Department of Biological Sciences, University of Alberta, CW405 Biological Sciences Building, Edmonton AB, Canada T6G 2E9
| | - Annemarie H Meijer
- Insitute of Biology, Leiden University, Clusius Laboratory, Wassenaarseweg 64, 2333 AL Leiden, The Netherlands
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42
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Affiliation(s)
- Hiroo Fukuda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan.
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43
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Zhong R, Ye ZH. amphivasal vascular bundle 1, a Gain-of-Function Mutation of the IFL1/REV Gene, Is Associated with Alterations in the Polarity of Leaves, Stems and Carpels. ACTA ACUST UNITED AC 2004; 45:369-85. [PMID: 15111711 DOI: 10.1093/pcp/pch051] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
In Arabidopsis stems, the vascular bundles in the stele are arranged in a ring-like pattern and the vascular tissues in each bundle are organized in a collateral pattern. We have shown previously that the semidominant amphivasal vascular bundle 1 (avb1) mutation transforms the collateral vascular bundles into amphivasal bundles and disrupts the ring-like arrangement of vascular bundles in the stele. In this study, we show that the avb1 mutation occurred in the putative microRNA 165 target sequence in the IFL1/REV gene and caused an amino acid substitution in the putative sterol/lipid-binding START domain. We present direct evidence that the wild-type IFL1/REV mRNA was cleaved within the microRNA 165 target sequence and the avb1 mutation resulted in an inhibition of cleavage and a higher level accumulation of full-length mRNA, suggesting a role of microRNA 165 in the regulation of IFL1/REV gene expression. In addition to an alteration in vascular patterning, the avb1 mutation also caused dramatic changes in fiber cell wall thickening and organ polarity, including aberrant formation and proliferation of cauline leaves and branches, production of trumpet-shaped leaves with reversed adaxial-abaxial identity, ectopic growth of carpel-like structures on the outer surface of carpels, and fasciation of inflorescence. Ectopic overexpression of the avb1 mutant cDNA not only phenocopied most of the avb1 mutant phenotypes but also led to additional novel phenotypes such as formation of leaves with extremely narrow blades and ectopic production of branches in the axil of siliques. Taken together, these results suggest that the avb1 gain-of-function mutation of the IFL1/REV gene alters the positional information that determines vascular patterning and organ polarity.
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Affiliation(s)
- Ruiqin Zhong
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
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44
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Ohashi-Ito K, Fukuda H. HD-Zip III Homeobox Genes that Include a Novel Member, ZeHB-13 (Zinnia)/ATHB-15 (Arabidopsis), are Involved in Procambium and Xylem Cell Differentiation. ACTA ACUST UNITED AC 2003; 44:1350-8. [PMID: 14701930 DOI: 10.1093/pcp/pcg164] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
HD-Zip III homeobox genes are known to be essential transcriptional factors for vascular development. To further understand the relation of HD-Zip III genes in vascular differentiation, we isolated a new member of the HD-Zip III genes, ZeHB-13, as a Zinnia homolog of ATHB-15, and then characterized the expression profile using a Zinnia xylogenic cell culture and Zinnia plants. We compared the accumulation pattern of transcripts for ZeHB-13 and other HD-Zip III genes and suggested that the expression of ZeHB-13 was restricted to the procambium and was not severely suppressed by brassinazole, an inhibitor of brassinosteroid biosynthesis, unlike other HD-Zip III genes. We also characterized its Arabidopsis counterpart, ATHB-15. A histochemical promoter analysis using ATHB-15::GUS transgenic Arabidopsis plants indicated that ATHB-15 was active specifically in the procambium. These results strongly suggest that ZeHB-13/ATHB-15 is a pivotal transcriptional regulator responsible for early vascular development. Based on these results, we will discuss the regulation of xylem development in light of the functions of HD-Zip III members and brassinosteroids.
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MESH Headings
- Amino Acid Sequence
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Arabidopsis/metabolism
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Asteraceae/genetics
- Asteraceae/growth & development
- Asteraceae/metabolism
- Base Sequence
- Cell Differentiation/genetics
- Cell Differentiation/physiology
- Cells, Cultured
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Plant
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Leucine Zippers/genetics
- Leucine Zippers/physiology
- Molecular Sequence Data
- Phylogeny
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plant Structures/genetics
- Plant Structures/growth & development
- Plant Structures/metabolism
- Plants, Genetically Modified
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Triazoles/pharmacology
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Affiliation(s)
- Kyoko Ohashi-Ito
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
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Emery JF, Floyd SK, Alvarez J, Eshed Y, Hawker NP, Izhaki A, Baum SF, Bowman JL. Radial Patterning of Arabidopsis Shoots by Class III HD-ZIP and KANADI Genes. Curr Biol 2003; 13:1768-74. [PMID: 14561401 DOI: 10.1016/j.cub.2003.09.035] [Citation(s) in RCA: 755] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Shoots of all land plants have a radial pattern that can be considered to have an adaxial (central)-abaxial (peripheral) polarity. In Arabidopsis, gain-of-function alleles of PHAVOLUTA and PHABULOSA, members of the class III HD-ZIP gene family, result in adaxialization of lateral organs. Conversely, loss-of-function alleles of the KANADI genes cause an adaxialization of lateral organs. Thus, the class III HD-ZIP and KANADI genes comprise a genetic system that patterns abaxial-adaxial polarity in lateral organs produced from the apical meristem. RESULTS We show that gain-of-function alleles of REVOLUTA, another member of the class III HD-ZIP gene family, are characterized by adaxialized lateral organs and alterations in the radial patterning of vascular bundles in the stem. The gain-of-function phenotype can be obtained by changing only the REVOLUTA mRNA sequence and without changing the protein sequence; this finding indicates that this phenotype is likely mediated through an interference with microRNA binding. Loss of KANADI activity results in similar alterations in vascular patterning as compared to REVOLUTA gain-of-function alleles. Simultaneous loss-of-function of PHABULOSA, PHAVOLUTA, and REVOLUTA abaxializes cotyledons, abolishes the formation of the primary apical meristem, and in severe cases, eliminates bilateral symmetry; these phenotypes implicate these three genes in radial patterning of both embryonic and postembryonic growth. CONCLUSIONS Based on complementary vascular and leaf phenotypes of class III HD-ZIP and KANADI mutants, we propose that a common genetic program dependent upon miRNAs governs adaxial-abaxial patterning of leaves and radial patterning of stems in the angiosperm shoot. This finding implies that a common patterning mechanism is shared between apical and vascular meristems.
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Affiliation(s)
- John F Emery
- Section of Plant Biology, University of California, Davis, Davis, CA 95616, USA
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Demura T, Tashiro G, Horiguchi G, Kishimoto N, Kubo M, Matsuoka N, Minami A, Nagata-Hiwatashi M, Nakamura K, Okamura Y, Sassa N, Suzuki S, Yazaki J, Kikuchi S, Fukuda H. Visualization by comprehensive microarray analysis of gene expression programs during transdifferentiation of mesophyll cells into xylem cells. Proc Natl Acad Sci U S A 2002; 99:15794-9. [PMID: 12438691 PMCID: PMC137795 DOI: 10.1073/pnas.232590499] [Citation(s) in RCA: 206] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Plants have a unique transdifferentiation mechanism by which differentiated cells can initiate a new program of differentiation. We used a comprehensive analysis of gene expression in an in vitro zinnia (Zinnia elegans L.) culture model system to gather fundamental information about the gene regulation underlying the transdifferentiation of plant cells. In this model, photosynthetic mesophyll cells isolated from zinnia leaves transdifferentiate into xylem cells in a morphogenic process characterized by features such as secondary-wall formation and programmed cell death. More than 8,000 zinnia cDNA clones were isolated from an equalized cDNA library prepared from cultured cells transdifferentiating into xylem cells. Microarray analysis using these cDNAs revealed several types of unique gene regulation patterns, including: the transient expression of a set of genes during cell isolation, presumably induced by wounding; a rapid reduction in the expression of photosynthetic genes and the rapid induction of protein synthesis-associated genes during the first stage; the preferential induction of auxin-related genes during the subsequent stage; and the transient induction of genes closely associated with particular morphogenetic events, including cell-wall formation and degradation and programmed cell death during the final stage. This analysis also revealed a number of previously uncharacterized genes encoding proteins that function in signal transduction, such as protein kinases and transcription factors that are expressed in a stage-specific manner. These findings provide new clues to the molecular mechanisms of both plant transdifferentiation and wood formation.
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Affiliation(s)
- Taku Demura
- Plant Science Center, RIKEN, 230-0045 Yokohama, Japan.
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