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Kaur A, Best NB, Hartwig T, Budka J, Khangura RS, McKenzie S, Aragón-Raygoza A, Strable J, Schulz B, Dilkes BP. A maize semi-dwarf mutant reveals a GRAS transcription factor involved in brassinosteroid signaling. PLANT PHYSIOLOGY 2024; 195:3072-3096. [PMID: 38709680 PMCID: PMC11288745 DOI: 10.1093/plphys/kiae147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 01/18/2024] [Accepted: 01/18/2024] [Indexed: 05/08/2024]
Abstract
Brassinosteroids (BR) and gibberellins (GA) regulate plant height and leaf angle in maize (Zea mays). Mutants with defects in BR or GA biosynthesis or signaling identify components of these pathways and enhance our knowledge about plant growth and development. In this study, we characterized three recessive mutant alleles of GRAS transcription factor 42 (gras42) in maize, a GRAS transcription factor gene orthologous to the DWARF AND LOW TILLERING (DLT) gene of rice (Oryza sativa). These maize mutants exhibited semi-dwarf stature, shorter and wider leaves, and more upright leaf angle. Transcriptome analysis revealed a role for GRAS42 as a determinant of BR signaling. Analysis of the expression consequences from loss of GRAS42 in the gras42-mu1021149 mutant indicated a weak loss of BR signaling in the mutant, consistent with its previously demonstrated role in BR signaling in rice. Loss of BR signaling was also evident by the enhancement of weak BR biosynthetic mutant alleles in double mutants of nana plant1-1 and gras42-mu1021149. The gras42-mu1021149 mutant had little effect on GA-regulated gene expression, suggesting that GRAS42 is not a regulator of core GA signaling genes in maize. Single-cell expression data identified gras42 expressed among cells in the G2/M phase of the cell cycle consistent with its previously demonstrated role in cell cycle gene expression in Arabidopsis (Arabidopsis thaliana). Cis-acting natural variation controlling GRAS42 transcript accumulation was identified by expression genome-wide association study (eGWAS) in maize. Our results demonstrate a conserved role for GRAS42/SCARECROW-LIKE 28 (SCL28)/DLT in BR signaling, clarify the role of this gene in GA signaling, and suggest mechanisms of tillering and leaf angle control by BR.
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Affiliation(s)
- Amanpreet Kaur
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Norman B Best
- Plant Genetics Research Unit, USDA-ARS, Columbia, MO 65211, USA
| | - Thomas Hartwig
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Josh Budka
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Rajdeep S Khangura
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Steven McKenzie
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Alejandro Aragón-Raygoza
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Josh Strable
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Burkhard Schulz
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA
| | - Brian P Dilkes
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
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2
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Best N, Dilkes B. Genetic evidence that brassinosteroids suppress pistils in the maize tassel independent of the jasmonic acid pathway. PLANT DIRECT 2023; 7:e501. [PMID: 37440932 PMCID: PMC10333885 DOI: 10.1002/pld3.501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 05/02/2023] [Accepted: 05/08/2023] [Indexed: 07/15/2023]
Abstract
The developmental genetics of reproductive structure control in maize must consider both the staminate florets of the tassel and the pistillate florets of the ear synflorescences. Pistil abortion takes place in the tassel florets, and stamen arrest is affected in ear florets to give rise to the monoecious nature of maize. Gibberellin (GA) deficiency results in increased tillering, a dwarfed plant syndrome, and the retention of anthers in the ear florets of maize. The silkless1 mutant results in suppression of silks in the ear. We demonstrate in this study that jasmonic acid (JA) and GA act independently and show additive phenotypes resulting in androecious dwarf1;silkless1 double mutant plants. The persistence of pistils in the tassel can be induced by multiple mechanisms, including JA deficiency, GA excess, genetic control of floral determinacy, and organ identity. The silkless1 mutant can suppress both silks in the ear and the silks in the tassel of JA-deficient and AP2 transcription factor tasselseed mutants. We previously demonstrated that GA production was required for brassinosteroid (BR) deficiency to affect persistence of pistils in the tassel. We find that BR deficiency affects pistil persistence by an independent mechanism from the silkless1 mutant and JA pathway. The silkless1 mutant did not prevent the formation of pistils in the tassel by nana plant2 in double mutants. In addition, we demonstrate that there is more to the silkless1 mutant than just a suppression of pistil growth. We document novel phenotypes of silkless1 mutants including weakly penetrant ear fasciation and anther persistence in the ear florets. Thus, the JA/AP2 mechanism of pistil retention in the tassel and silk growth in the ear are similarly sensitive to loss of the SILKLESS1 protein, while the BR/GA mechanism is not.
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Affiliation(s)
- Norman Best
- Agriculture Research Service, Plant Genetics Research UnitUSDAColumbiaMissouriUSA
| | - Brian Dilkes
- Department of BiochemistryPurdue UniversityWest LafayetteIndianaUSA
- Center for Plant BiologyPurdue UniversityWest LafayetteIndianaUSA
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3
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Hartwig T, Banf M, Prietsch GP, Zhu JY, Mora-Ramírez I, Schippers JHM, Snodgrass SJ, Seetharam AS, Huettel B, Kolkman JM, Yang J, Engelhorn J, Wang ZY. Hybrid allele-specific ChIP-seq analysis identifies variation in brassinosteroid-responsive transcription factor binding linked to traits in maize. Genome Biol 2023; 24:108. [PMID: 37158941 PMCID: PMC10165856 DOI: 10.1186/s13059-023-02909-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 03/23/2023] [Indexed: 05/10/2023] Open
Abstract
BACKGROUND Genetic variation in regulatory sequences that alter transcription factor (TF) binding is a major cause of phenotypic diversity. Brassinosteroid is a growth hormone that has major effects on plant phenotypes. Genetic variation in brassinosteroid-responsive cis-elements likely contributes to trait variation. Pinpointing such regulatory variations and quantitative genomic analysis of the variation in TF-target binding, however, remains challenging. How variation in transcriptional targets of signaling pathways such as the brassinosteroid pathway contributes to phenotypic variation is an important question to be investigated with innovative approaches. RESULTS Here, we use a hybrid allele-specific chromatin binding sequencing (HASCh-seq) approach and identify variations in target binding of the brassinosteroid-responsive TF ZmBZR1 in maize. HASCh-seq in the B73xMo17 F1s identifies thousands of target genes of ZmBZR1. Allele-specific ZmBZR1 binding (ASB) has been observed for 18.3% of target genes and is enriched in promoter and enhancer regions. About a quarter of the ASB sites correlate with sequence variation in BZR1-binding motifs and another quarter correlate with haplotype-specific DNA methylation, suggesting that both genetic and epigenetic variations contribute to the high level of variation in ZmBZR1 occupancy. Comparison with GWAS data shows linkage of hundreds of ASB loci to important yield and disease-related traits. CONCLUSION Our study provides a robust method for analyzing genome-wide variations of TF occupancy and identifies genetic and epigenetic variations of the brassinosteroid response transcription network in maize.
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Affiliation(s)
- Thomas Hartwig
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA.
- Heinrich-Heine University, Universitätsstraße 1, Düsseldorf, NRW, 40225, Germany.
- Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, NRW, 50829, Germany.
| | - Michael Banf
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Gisele Passaia Prietsch
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Jia-Ying Zhu
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstraße 3, Seeland, SA, 06466, Germany
| | - Isabel Mora-Ramírez
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstraße 3, Seeland, SA, 06466, Germany
| | - Jos H M Schippers
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstraße 3, Seeland, SA, 06466, Germany
| | - Samantha J Snodgrass
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, 339A Bessey Hall, Ames, IA, 50011, USA
| | - Arun S Seetharam
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, 339A Bessey Hall, Ames, IA, 50011, USA
| | - Bruno Huettel
- Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, NRW, 50829, Germany
| | - Judith M Kolkman
- School of Integrative Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, 413 Bradfield Hall, Ithaca, NY, 14853, USA
| | - Jinliang Yang
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, 363 Keim Hall, Lincoln, NE, 68583, USA
| | - Julia Engelhorn
- Heinrich-Heine University, Universitätsstraße 1, Düsseldorf, NRW, 40225, Germany
- Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, Cologne, NRW, 50829, Germany
| | - Zhi-Yong Wang
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA.
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Li Q, Liu N, Wu C. Novel insights into maize (Zea mays) development and organogenesis for agricultural optimization. PLANTA 2023; 257:94. [PMID: 37031436 DOI: 10.1007/s00425-023-04126-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 03/22/2023] [Indexed: 06/19/2023]
Abstract
In maize, intrinsic hormone activities and sap fluxes facilitate organogenesis patterning and plant holistic development; these hormone movements should be a primary focus of developmental biology and agricultural optimization strategies. Maize (Zea mays) is an important crop plant with distinctive life history characteristics and structural features. Genetic studies have extended our knowledge of maize developmental processes, genetics, and molecular ecophysiology. In this review, the classical life cycle and life history strategies of maize are analyzed to identify spatiotemporal organogenesis properties and develop a definitive understanding of maize development. The actions of genes and hormones involved in maize organogenesis and sex determination, along with potential molecular mechanisms, are investigated, with findings suggesting central roles of auxin and cytokinins in regulating maize holistic development. Furthermore, investigation of morphological and structural characteristics of maize, particularly node ubiquity and the alternate attachment pattern of lateral organs, yields a novel regulatory model suggesting that maize organ initiation and subsequent development are derived from the stimulation and interaction of auxin and cytokinin fluxes. Propositions that hormone activities and sap flow pathways control organogenesis are thoroughly explored, and initiation and development processes of distinctive maize organs are discussed. Analysis of physiological factors driving hormone and sap movement implicates cues of whole-plant activity for hormone and sap fluxes to stimulate maize inflorescence initiation and organ identity determination. The physiological origins and biogenetic mechanisms underlying maize floral sex determination occurring at the tassel and ear spikelet are thoroughly investigated. The comprehensive outline of maize development and morphogenetic physiology developed in this review will enable farmers to optimize field management and will provide a reference for de novo crop domestication and germplasm improvement using genome editing biotechnologies, promoting agricultural optimization.
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Affiliation(s)
- Qinglin Li
- Crop Genesis and Novel Agronomy Center, Yangling, 712100, Shaanxi, China.
| | - Ning Liu
- Shandong ZhongnongTiantai Seed Co., Ltd, Pingyi, 273300, Shandong, China
| | - Chenglai Wu
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
- College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
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5
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Draves MA, Muench RL, Lang MG, Kelley DR. Maize Seedling Growth and Hormone Response Assays Using the Rolled Towel Method. Curr Protoc 2022; 2:e562. [PMID: 36194012 DOI: 10.1002/cpz1.562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Root system architecture is a critical factor in maize health and stress resilience. Determining the genetic and environmental factors that shape maize root system architecture is an active research area. However, the ability to phenotype juvenile root systems is hindered by the use of field-grown and soil-based systems. An alternative to soil- and field-based growing conditions for maize seedlings is a controlled environment with a soil-free medium, which can facilitate root system phenotyping. Here, we describe how to grow maize under soil-free conditions for up to 12 days to facilitate root phenotyping. Maize seeds are sterilized and planted on specialized seed germination paper to minimize fungal contamination and ensure synchronized seedling growth, followed by imaging at the desired time point. The root images are then analyzed to quantify traits of interest, such as primary root length, lateral root density, seminal root length, and seminal root number. In addition, juvenile shoot traits can be quantified using manual annotation methods. We also outline the steps for performing rigorous hormone response assays for four classical phytohormones: auxin, brassinosteroid, cytokinin, and jasmonic acid. This protocol can be rapidly scaled up and is compatible with genetic screens and sample collection for downstream molecular analyses such as transcriptomics and proteomics. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Maize seedling rolled towel assay and phenotyping Basic Protocol 2: Maize seedling hormone response assays using the rolled towel assay.
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Affiliation(s)
- Melissa A Draves
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Rebekah L Muench
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Michelle G Lang
- Current address: Corteva Agriscience, 8325 NW 62nd Ave, Johnston, Iowa
| | - Dior R Kelley
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
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6
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Best NB, Dilkes BP. Transcriptional responses to gibberellin in the maize tassel and control by DELLA domain proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:493-517. [PMID: 36050832 PMCID: PMC9826531 DOI: 10.1111/tpj.15961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 08/23/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
The plant hormone gibberellin (GA) impacts plant growth and development differently depending on the developmental context. In the maize (Zea mays) tassel, application of GA alters floral development, resulting in the persistence of pistils. GA signaling is achieved by the GA-dependent turnover of DELLA domain transcription factors, encoded by dwarf8 (d8) and dwarf9 (d9) in maize. The D8-Mpl and D9-1 alleles disrupt GA signaling, resulting in short plants and normal tassel floret development in the presence of excess GA. However, D9-1 mutants are unable to block GA-induced pistil development. Gene expression in developing tassels of D8-Mpl and D9-1 mutants and their wild-type siblings was determined upon excess GA3 and mock treatments. Using GA-sensitive transcripts as reporters of GA signaling, we identified a weak loss of repression under mock conditions in both mutants, with the effect in D9-1 being greater. D9-1 was also less able to repress GA signaling in the presence of excess GA3 . We treated a diverse set of maize inbred lines with excess GA3 and measured the phenotypic consequences on multiple aspects of development (e.g., height and pistil persistence in tassel florets). Genotype affected all GA-regulated phenotypes but there was no correlation between any of the GA-affected phenotypes, indicating that the complexity of the relationship between GA and development extends beyond the two-gene epistasis previously demonstrated for GA and brassinosteroid biosynthetic mutants.
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Affiliation(s)
- Norman B. Best
- USDAAgriculture Research Service, Plant Genetics Research UnitColumbiaMissouri65211USA
| | - Brian P. Dilkes
- Department of BiochemistryPurdue University; West LafayetteIndiana47907USA
- Center for Plant BiologyPurdue UniversityWest LafayetteIndiana47907USA
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7
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Xiang L, Nolan TM, Bao Y, Elmore M, Tuel T, Gai J, Shah D, Wang P, Huser NM, Hurd AM, McLaughlin SA, Howell SH, Walley JW, Yin Y, Tang L. Robotic Assay for Drought (RoAD): an automated phenotyping system for brassinosteroid and drought responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1837-1853. [PMID: 34216161 DOI: 10.1111/tpj.15401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 06/13/2023]
Abstract
Brassinosteroids (BRs) are a group of plant steroid hormones involved in regulating growth, development, and stress responses. Many components of the BR pathway have previously been identified and characterized. However, BR phenotyping experiments are typically performed in a low-throughput manner, such as on Petri plates. Additionally, the BR pathway affects drought responses, but drought experiments are time consuming and difficult to control. To mitigate these issues and increase throughput, we developed the Robotic Assay for Drought (RoAD) system to perform BR and drought response experiments in soil-grown Arabidopsis plants. RoAD is equipped with a robotic arm, a rover, a bench scale, a precisely controlled watering system, an RGB camera, and a laser profilometer. It performs daily weighing, watering, and imaging tasks and is capable of administering BR response assays by watering plants with Propiconazole (PCZ), a BR biosynthesis inhibitor. We developed image processing algorithms for both plant segmentation and phenotypic trait extraction to accurately measure traits including plant area, plant volume, leaf length, and leaf width. We then applied machine learning algorithms that utilize the extracted phenotypic parameters to identify image-derived traits that can distinguish control, drought-treated, and PCZ-treated plants. We carried out PCZ and drought experiments on a set of BR mutants and Arabidopsis accessions with altered BR responses. Finally, we extended the RoAD assays to perform BR response assays using PCZ in Zea mays (maize) plants. This study establishes an automated and non-invasive robotic imaging system as a tool to accurately measure morphological and growth-related traits of Arabidopsis and maize plants in 3D, providing insights into the BR-mediated control of plant growth and stress responses.
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Affiliation(s)
- Lirong Xiang
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Trevor M Nolan
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
- Plant Sciences Institutes, Iowa State University, Ames, IA, 50011, USA
| | - Yin Bao
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Mitch Elmore
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA
| | - Taylor Tuel
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Jingyao Gai
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Dylan Shah
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Ping Wang
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
| | - Nicole M Huser
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
| | - Ashley M Hurd
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
| | - Sean A McLaughlin
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
| | - Stephen H Howell
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
- Plant Sciences Institutes, Iowa State University, Ames, IA, 50011, USA
| | - Justin W Walley
- Plant Sciences Institutes, Iowa State University, Ames, IA, 50011, USA
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA
| | - Yanhai Yin
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
- Plant Sciences Institutes, Iowa State University, Ames, IA, 50011, USA
| | - Lie Tang
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, 50011, USA
- Plant Sciences Institutes, Iowa State University, Ames, IA, 50011, USA
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8
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Wu M, Goldshmidt A, Ovadya D, Larue H. I am all ears: Maximize maize doubled haploid success by promoting axillary branch elongation. PLANT DIRECT 2020; 4:e00226. [PMID: 32426692 PMCID: PMC7227119 DOI: 10.1002/pld3.226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 03/26/2020] [Accepted: 04/20/2020] [Indexed: 06/11/2023]
Abstract
The maize doubled haploid (DH) technology plays an important role in accelerating breeding genetic gain. One major challenge in fully leveraging the potential of DH technology to accelerate genetic gain is obtaining a consistent seed return from haploid (DH0) plants after chromosome doubling. Here we demonstrated that DH0 seed production can be increased by increasing the number of mature axillary female inflorescences (ears) at anthesis. To determine the maximum capacity of a maize plant to develop ears, we first characterized the developmental progression of every axillary meristem. We found that all axillary meristems developed to a similar developmental stage before the reproductive transition of the shoot apical meristem (SAM). Upon reproductive transition of the SAM, all axillary meristems are released for reproductive development into ears in a developmental gradient reflective on their positions along the main stem. However, under most circumstances only the top one or two ears can generate silks at anthesis. We found that applying the GA inhibitor paclobutrazol (PAC) during the early reproductive transition of axillary meristems increased the number of silking ears at anthesis, leading to increased success of self-pollination and seed production. These results provide a blueprint to improve DH efficiency and demonstrate the potential of breeding innovation through understanding crops' developmental processes.
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Affiliation(s)
| | - Alexander Goldshmidt
- Bayer U.S. ‐ Crop ScienceChesterfieldMOUSA
- Present address:
Department of Field Crops ScienceInstitute of Plant ScienceAgricultural Research OrganizationThe Volcani CenterRishon LezionIsrael
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9
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Farrow J, Bellinger M, Rasmussen C. In vitro Conditions for Dark Growth and Analysis of Maize Seedlings. Bio Protoc 2020. [DOI: 10.21769/bioprotoc.3555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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10
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Rozhon W, Akter S, Fernandez A, Poppenberger B. Inhibitors of Brassinosteroid Biosynthesis and Signal Transduction. Molecules 2019; 24:E4372. [PMID: 31795392 PMCID: PMC6930552 DOI: 10.3390/molecules24234372] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 12/19/2022] Open
Abstract
Chemical inhibitors are invaluable tools for investigating protein function in reverse genetic approaches. Their application bears many advantages over mutant generation and characterization. Inhibitors can overcome functional redundancy, their application is not limited to species for which tools of molecular genetics are available and they can be applied to specific tissues or developmental stages, making them highly convenient for addressing biological questions. The use of inhibitors has helped to elucidate hormone biosynthesis and signaling pathways and here we review compounds that were developed for the plant hormones brassinosteroids (BRs). BRs are steroids that have strong growth-promoting capacities, are crucial for all stages of plant development and participate in adaptive growth processes and stress response reactions. In the last two decades, impressive progress has been made in BR inhibitor development and application, which has been instrumental for studying BR modes of activity and identifying and characterizing key players. Both, inhibitors that target biosynthesis, such as brassinazole, and inhibitors that target signaling, such as bikinin, exist and in a comprehensive overview we summarize knowledge and methodology that enabled their design and key findings of their use. In addition, the potential of BR inhibitors for commercial application in plant production is discussed.
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Affiliation(s)
- Wilfried Rozhon
- Biotechnology of Horticultural Crops, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany
| | | | | | - Brigitte Poppenberger
- Biotechnology of Horticultural Crops, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany
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11
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Neill EM, Byrd MCR, Billman T, Brandizzi F, Stapleton AE. Plant growth regulators interact with elevated temperature to alter heat stress signaling via the Unfolded Protein Response in maize. Sci Rep 2019. [PMID: 31316112 DOI: 10.1101/532796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Plants are increasingly exposed to high temperatures, which can cause accumulation of unfolded protein in the endoplasmic reticulum (ER). This condition, known as ER stress, evokes the unfolded protein response (UPR), a cytoprotective signaling pathway. One important branch of the UPR is regulated by splicing of bZIP60 mRNA by the IRE1 stress sensor. There is increasing evidence that commercial plant growth regulators may protect against abiotic stressors including heat stress and drought, but there is very little mechanistic information about these effects or about the regulatory pathways involved. We evaluated evidence in the B73 Zea mays inbred for differences in the activity of the UPR between permissive and elevated temperature in conjunction with plant growth regulator application. Treatment with elevated temperature and plant growth regulators increased UPR activation, as assessed by an increase in splicing of the mRNA of the IRE1 target bZIP60 following paclobutrazol treatment. We propose that plant growth regulator treatment induces bZIP60 mRNA splicing which 'primes' plants for rapid adaptive response to subsequent endoplasmic reticulum-stress inducing conditions.
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Affiliation(s)
- Elena M Neill
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
- North Carolina Department of Health and Human Services, State Laboratory of Public Health, Raleigh, NC, USA
| | - Michael C R Byrd
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
| | - Thomas Billman
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
- Blue Cross and Blue Shield of North Carolina, Underwriting Division, Durham, NC, USA
| | - Federica Brandizzi
- Michigan State University, Department of Plant Biology, East Lansing, MI, USA
| | - Ann E Stapleton
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA.
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12
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Neill EM, Byrd MCR, Billman T, Brandizzi F, Stapleton AE. Plant growth regulators interact with elevated temperature to alter heat stress signaling via the Unfolded Protein Response in maize. Sci Rep 2019; 9:10392. [PMID: 31316112 PMCID: PMC6637120 DOI: 10.1038/s41598-019-46839-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 07/03/2019] [Indexed: 01/09/2023] Open
Abstract
Plants are increasingly exposed to high temperatures, which can cause accumulation of unfolded protein in the endoplasmic reticulum (ER). This condition, known as ER stress, evokes the unfolded protein response (UPR), a cytoprotective signaling pathway. One important branch of the UPR is regulated by splicing of bZIP60 mRNA by the IRE1 stress sensor. There is increasing evidence that commercial plant growth regulators may protect against abiotic stressors including heat stress and drought, but there is very little mechanistic information about these effects or about the regulatory pathways involved. We evaluated evidence in the B73 Zea mays inbred for differences in the activity of the UPR between permissive and elevated temperature in conjunction with plant growth regulator application. Treatment with elevated temperature and plant growth regulators increased UPR activation, as assessed by an increase in splicing of the mRNA of the IRE1 target bZIP60 following paclobutrazol treatment. We propose that plant growth regulator treatment induces bZIP60 mRNA splicing which 'primes' plants for rapid adaptive response to subsequent endoplasmic reticulum-stress inducing conditions.
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Affiliation(s)
- Elena M Neill
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
- North Carolina Department of Health and Human Services, State Laboratory of Public Health, Raleigh, NC, USA
| | - Michael C R Byrd
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
| | - Thomas Billman
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA
- Blue Cross and Blue Shield of North Carolina, Underwriting Division, Durham, NC, USA
| | - Federica Brandizzi
- Michigan State University, Department of Plant Biology, East Lansing, MI, USA
| | - Ann E Stapleton
- University of North Carolina Wilmington, Department of Biology and Marine Biology, Department of Mathematics and Statistics, Wilmington, NC, USA.
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