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Ramirez‐Corona B, Seagren E, Sherman C, Imaizumi T, Queitsch C, Cuperus J. Sensitivity to Photoperiod Is a Complex Trait in Camelina sativa. PLANT DIRECT 2025; 9:e70071. [PMID: 40242791 PMCID: PMC11999801 DOI: 10.1002/pld3.70071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2024] [Revised: 03/10/2025] [Accepted: 04/05/2025] [Indexed: 04/18/2025]
Abstract
Day neutrality, or insensitivity to photoperiod (day length), is an important domestication trait in many crop species. Although the oilseed crop C. sativa has been cultivated since the Neolithic era, day-neutral accessions have yet to be described. We sought to leverage genetic diversity in existing germplasms to identify C. sativa accessions with low photoperiod sensitivity for future engineering of this trait. To do so, we quantified variation in hypocotyl length across 161 C. sativa accessions of 4-day-old seedlings grown in long-day and short-day conditions as a high-throughput approximation of variation in the photoperiod response. Soil-grown adult plants from selected accessions also showed variation in the response to day length in several traits; however, the responses in seedling and adult traits were not correlated, suggesting complex mechanistic underpinnings. Although RNA-seq experiments of the reference accession Licalla identified several differentially regulated Arabidopsis syntelogs involved in photoperiod response and development, including COL2, FT, LHY, and WOX4, expression of these genes in the accessions did not correlate with differences in their photoperiod sensitivity. Taken together, we show that all tested accessions show some degree of photoperiod response and that this trait is likely complex, involving several and separable seedling and adult traits.
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Affiliation(s)
| | - Erin Seagren
- Department of Genome SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Carissa Sherman
- Department of Genome SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Takato Imaizumi
- Department of BiologyUniversity of WashingtonSeattleWashingtonUSA
| | - Christine Queitsch
- Department of Genome SciencesUniversity of WashingtonSeattleWashingtonUSA
- Brotman Baty Institute for Precision MedicineUniversity of WashingtonSeattleWashingtonUSA
| | - Josh Cuperus
- Department of Genome SciencesUniversity of WashingtonSeattleWashingtonUSA
- Brotman Baty Institute for Precision MedicineUniversity of WashingtonSeattleWashingtonUSA
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2
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Cox KL, Pardi SA, O'Connor L, Klebanovych A, Huss D, Nusinow DA, Meyers BC, Czymmek KJ. ExPOSE: a comprehensive toolkit to perform expansion microscopy in plant protoplast systems. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2025; 121:e70049. [PMID: 40051203 PMCID: PMC11885898 DOI: 10.1111/tpj.70049] [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: 07/22/2024] [Revised: 01/31/2025] [Accepted: 02/05/2025] [Indexed: 03/10/2025]
Abstract
Expansion microscopy (ExM) achieves nanoscale imaging by physical expansion of fixed biological tissues embedded in a swellable hydrogel, enhancing the resolution of any optical microscope several-fold. While ExM is commonly used in animal cells and tissues, there are few plant-specific protocols. Protoplasts are a widely used cell system across plant species, especially in studying biomolecule localization. Here, we present an approach to achieve robust expansion of plant protoplasts, termed Expansion microscopy in plant PrOtoplast SystEms (ExPOSE). We demonstrate that coupling ExPOSE with other imaging techniques, immunofluorescence and in situ hybridization chain reaction to visualize proteins and mRNAs, respectively, greatly enhances the spatial resolution of endogenous biomolecules. Additionally, in this study, we tested the effectiveness and versatility of this technique to observe biomolecular condensates in Arabidopsis protoplasts and transcription factors in maize protoplasts at increased resolution. ExPOSE can be relatively inexpensive, fast, and simple to implement.
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Affiliation(s)
- Kevin L. Cox
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
- Howard Hughes Medical InstituteChevy ChaseMaryland20815USA
- Plant and Microbial Biosciences Program, Division of Biology and Biomedical SciencesWashington University in Saint LouisSt. LouisMissouri63130USA
| | - Sarah A. Pardi
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
- Plant and Microbial Biosciences Program, Division of Biology and Biomedical SciencesWashington University in Saint LouisSt. LouisMissouri63130USA
| | - Lily O'Connor
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
- Plant and Microbial Biosciences Program, Division of Biology and Biomedical SciencesWashington University in Saint LouisSt. LouisMissouri63130USA
| | | | - David Huss
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
| | | | - Blake C. Meyers
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
- Division of Plant Science and TechnologyUniversity of MissouriColumbiaMissouri65211USA
- The Genome CenterUniversity of CaliforniaDavisDavisCalifornia95616USA
- Department of Plant SciencesUniversity of CaliforniaDavisDavisCalifornia95616USA
| | - Kirk J. Czymmek
- Donald Danforth Plant Science CenterSt. LouisMissouri63132USA
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3
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Farid B, Saddique MAB, Tahir MHN, Ikram RM, Ali Z, Akbar W. Expression divergence of BAG gene family in maize under heat stress. BMC PLANT BIOLOGY 2025; 25:16. [PMID: 39754085 PMCID: PMC11699707 DOI: 10.1186/s12870-024-06020-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2024] [Accepted: 12/26/2024] [Indexed: 01/06/2025]
Abstract
Heat stress poses a significant challenge for maize production, especially during the spring when high temperatures disrupt cellular processes, impeding plant growth and development. The B-cell lymphoma-2 (Bcl-2) associated athanogene (BAG) gene family is known to be relatively conserved across various species. It plays a crucial role as molecular chaperone cofactors that are responsible for programmed cell death and tumorigenesis. Once the plant is under heat stress, the BAG genes act as co-chaperones and modulate the molecular functions of HSP70/HSC70 saving the plant from the damage of high temperature stress. The study was planned to identify and characterize the BAG genes for heat stress responsiveness in maize. Twenty-one (21) BAG genes were identified in the latest maize genome. The evolutionary relationship of Zea mays BAGs (ZmBAGs) with Arabidopsis thaliana, Solanum lycopersicum, Theobroma cacao, Sorghum bicolor, Ananas comosus, Physcomitrium patens, Oryza sativa and Populus trichocarpa were represented by the phylogenetic analysis. Differential expressions of BAG gene family in leaf, endosperm, anther, silk, seed and developing embryo depict their contribution to the growth and development. The in-silico gene expression analysis indicated ZmBAG-8 (Zm00001eb170080), and ZmBAG-11 (Zm00001eb237960) showed higher expression under abiotic stresses (cold, heat and salinity). The RT-qPCR further confirmed the expression of ZmBAG-8 and ZmBAG-11 in plant leaf tissue across the contrasting inbred lines and their F1 hybrid (DR-139, UML-1 and DR-139 × UML-1) when exposed to heat stress. Furthermore, the protein-protein interaction networks of ZmBAG-8 and ZmBAG-11 further elucidated their role in stress tolerance related pathways. This research offers a roadmap to plan functional research and utilize ZmBAG genes to enhance heat tolerance in grasses.
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Affiliation(s)
- Babar Farid
- Institute of Plant Breeding and Biotechnology, MNS University of Agriculture, Multan, Pakistan
| | | | | | | | - Zulfiqar Ali
- Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan
- Programs and Projects Department, Islamic Organization for Food Security, Astana, Republic of Kazakhstan
| | - Waseem Akbar
- Maize and Millet Research Institute, Yousafwala, Sahiwal, Pakistan
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4
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Jiang B. Light-induced cryptochrome 2 liquid-liquid phase separation and mRNA methylation. THE NEW PHYTOLOGIST 2024; 244:2163-2169. [PMID: 39434460 DOI: 10.1111/nph.20201] [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: 07/15/2024] [Accepted: 09/09/2024] [Indexed: 10/23/2024]
Abstract
Light is essential not only for photosynthesis but also for the regulation of various physiological and developmental processes in plants. While the mechanisms by which light regulates transcription and protein stability are well established, the effects of light on RNA methylation and their subsequent impact on plant growth and development are less understood. Upon exposure to blue light, the photoreceptor cryptochromes form nuclear speckles or nuclear bodies, termed CRY photobodies. The CRY2 photobodies undergo light-induced homo-oligomerization and liquid-liquid phase separation (LLPS), which are crucial for their physiological activity. Recent studies have proposed that blue light-induced CRY2 LLPS increases the local concentration or directly enhances the biochemical activities of RNA N6-methyladenosine (m6A) methyltransferases, thus, to regulate circadian clock and maintain Chl homeostasis through processes of RNA decay or translation. This review aimed to elucidate the functions of CRY2 and LLPS in RNA methylation, focusing on the light-controlled reversible phase transitions regulon and the outstanding questions that remain in RNA methylation.
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Affiliation(s)
- Bochen Jiang
- School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
- Sycamore Research Institute of Life Sciences, Shanghai, 201203, China
- Department of Chemistry, The University of Chicago, Chicago, IL, 60637, USA
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5
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Casal JJ, Murcia G, Bianchimano L. Plant Thermosensors. Annu Rev Genet 2024; 58:135-158. [PMID: 38986032 DOI: 10.1146/annurev-genet-111523-102327] [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: 07/12/2024]
Abstract
Plants are exposed to temperature conditions that fluctuate over different time scales, including those inherent to global warming. In the face of these variations, plants sense temperature to adjust their functions and minimize the negative consequences. Transcriptome responses underlie changes in growth, development, and biochemistry (thermomorphogenesis and acclimation to extreme temperatures). We are only beginning to understand temperature sensation by plants. Multiple thermosensors convey complementary temperature information to a given signaling network to control gene expression. Temperature-induced changes in protein or transcript structure and/or in the dynamics of biomolecular condensates are the core sensing mechanisms of known thermosensors, but temperature impinges on their activities via additional indirect pathways. The diversity of plant responses to temperature anticipates that many new thermosensors and eventually novel sensing mechanisms will be uncovered soon.
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Affiliation(s)
- Jorge J Casal
- Fundación Instituto Leloir and IIBBA-CONICET, Buenos Aires, Argentina; ,
- Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Universidad de Buenos Aires and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina;
| | - Germán Murcia
- Fundación Instituto Leloir and IIBBA-CONICET, Buenos Aires, Argentina; ,
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Battle MW, Ewing SF, Dickson C, Obaje J, Edgeworth KN, Bindbeutel R, Antoniou-Kourounioti RL, Nusinow DA, Jones MA. Manipulation of photosensory and circadian signaling restricts phenotypic plasticity in response to changing environmental conditions in Arabidopsis. MOLECULAR PLANT 2024; 17:1458-1471. [PMID: 39014898 DOI: 10.1016/j.molp.2024.07.007] [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: 03/15/2024] [Revised: 06/14/2024] [Accepted: 07/11/2024] [Indexed: 07/18/2024]
Abstract
Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions. Interpretation of light and temperature signals is aided by the circadian system, which provides a temporal context. Phenotypic plasticity provides a selective and competitive advantage in nature but is obstructive during large-scale, intensive agricultural practices since economically important traits (including vegetative growth and flowering time) can vary widely depending on local environmental conditions. This prevents accurate prediction of harvesting times and produces a variable crop. In this study, we sought to restrict phenotypic plasticity and circadian regulation by manipulating signaling systems that govern plants' responses to environmental signals. Mathematical modeling of plant growth and development predicted reduced plant responses to changing environments when circadian and light signaling pathways were manipulated. We tested this prediction by utilizing a constitutively active allele of the plant photoreceptor phytochrome B, along with disruption of the circadian system via mutation of EARLY FLOWERING3. We found that these manipulations produced plants that are less responsive to light and temperature cues and thus fail to anticipate dawn. These engineered plants have uniform vegetative growth and flowering time, demonstrating how phenotypic plasticity can be limited while maintaining plant productivity. This has significant implications for future agriculture in both open fields and controlled environments.
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Affiliation(s)
- Martin William Battle
- Plant Science Group, School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Scott Fraser Ewing
- Plant Science Group, School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Cathryn Dickson
- Plant Science Group, School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Joseph Obaje
- Plant Science Group, School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Kristen N Edgeworth
- Danforth Plant Science Center, St. Louis, MO 63132, USA; Department of Biological and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO 63130, USA
| | | | | | | | - Matthew Alan Jones
- Plant Science Group, School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, UK.
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Xu M, Wang YY, Wu Y, Zhou X, Shan Z, Tao K, Qian K, Wang X, Li J, Wu Q, Deng XW, Ling JJ. Green light mediates atypical photomorphogenesis by dual modulation of Arabidopsis phytochromes B and A. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:1915-1933. [PMID: 39023402 DOI: 10.1111/jipb.13742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 06/20/2024] [Accepted: 06/25/2024] [Indexed: 07/20/2024]
Abstract
Although green light (GL) is located in the middle of the visible light spectrum and regulates a series of plant developmental processes, the mechanism by which it regulates seedling development is largely unknown. In this study, we demonstrated that GL promotes atypical photomorphogenesis in Arabidopsis thaliana via the dual regulations of phytochrome B (phyB) and phyA. Although the Pr-to-Pfr conversion rates of phyB and phyA under GL were lower than those under red light (RL) in a fluence rate-dependent and time-dependent manner, long-term treatment with GL induced high Pfr/Pr ratios of phyB and phyA. Moreover, GL induced the formation of numerous small phyB photobodies in the nucleus, resulting in atypical photomorphogenesis, with smaller cotyledon opening angles and longer hypocotyls in seedlings compared to RL. The abundance of phyA significantly decreased after short- and long-term GL treatments. We determined that four major PHYTOCHROME-INTERACTING FACTORs (PIFs: PIF1, PIF3, PIF4, and PIF5) act downstream of phyB in GL-mediated cotyledon opening. In addition, GL plays opposite roles in regulating different PIFs. For example, under continuous GL, the protein levels of all PIFs decreased, whereas the transcript levels of PIF4 and PIF5 strongly increased compared with dark treatment. Taken together, our work provides a detailed molecular framework for understanding the role of the antagonistic regulations of phyB and phyA in GL-mediated atypical photomorphogenesis.
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Affiliation(s)
- Miqi Xu
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Yi-Yuan Wang
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Yujie Wu
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Xiuhong Zhou
- Biotechnology Center, State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, Hefei, 230036, China
| | - Ziyan Shan
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Kunying Tao
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Kaiqiang Qian
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Xuncheng Wang
- Beijing Key Laboratory of Environment Friendly Management on Fruit Diseases and Pests in North China, Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China
| | - Jian Li
- College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Qingqing Wu
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Xing Wang Deng
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Advanced Agriculture Sciences, and School of Life Sciences, Peking University, Beijing, 100871, China
- State Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Sciences, Weifang, 261000, China
| | - Jun-Jie Ling
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
- Province Key Laboratory of Resource Insect Biology and Innovative Utilization, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
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8
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Willige BC, Yoo CY, Saldierna Guzmán JP. What is going on inside of phytochrome B photobodies? THE PLANT CELL 2024; 36:2065-2085. [PMID: 38511271 PMCID: PMC11132900 DOI: 10.1093/plcell/koae084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/20/2023] [Accepted: 01/08/2024] [Indexed: 03/22/2024]
Abstract
Plants exhibit an enormous phenotypic plasticity to adjust to changing environmental conditions. For this purpose, they have evolved mechanisms to detect and measure biotic and abiotic factors in their surroundings. Phytochrome B exhibits a dual function, since it serves as a photoreceptor for red and far-red light as well as a thermosensor. In 1999, it was first reported that phytochromes not only translocate into the nucleus but also form subnuclear foci upon irradiation by red light. It took more than 10 years until these phytochrome speckles received their name; these foci were coined photobodies to describe unique phytochrome-containing subnuclear domains that are regulated by light. Since their initial discovery, there has been much speculation about the significance and function of photobodies. Their presumed roles range from pure experimental artifacts to waste deposits or signaling hubs. In this review, we summarize the newest findings about the meaning of phyB photobodies for light and temperature signaling. Recent studies have established that phyB photobodies are formed by liquid-liquid phase separation via multivalent interactions and that they provide diverse functions as biochemical hotspots to regulate gene expression on multiple levels.
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Affiliation(s)
- Björn Christopher Willige
- Department of Soil and Crop Sciences, College of Agricultural Sciences, Colorado State University, Fort Collins, CO 80521, USA
| | - Chan Yul Yoo
- School of Biological Sciences, University of Utah, UT 84112, USA
| | - Jessica Paola Saldierna Guzmán
- Department of Soil and Crop Sciences, College of Agricultural Sciences, Colorado State University, Fort Collins, CO 80521, USA
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9
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Kwon Y, Kim C, Choi G. Phytochrome B photobody components. THE NEW PHYTOLOGIST 2024; 242:909-915. [PMID: 38477037 DOI: 10.1111/nph.19675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024]
Abstract
Phytochrome B (phyB) is a red and far-red photoreceptor that promotes light responses. Upon photoactivation, phyB enters the nucleus and forms a molecular condensate called a photobody through liquid-liquid phase separation. Phytochrome B photobody comprises phyB, the main scaffold molecule, and at least 37 client proteins. These clients belong to diverse functional categories enriched with transcription regulators, encompassing both positive and negative light signaling factors, with the functional bias toward the negative factors. The functionally diverse clients suggest that phyB photobody acts either as a trap to capture proteins, including negatively acting transcription regulators, for processes such as sequestration, modification, or degradation or as a hub where proteins are brought into close proximity for interaction in a light-dependent manner.
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Affiliation(s)
- Yongmin Kwon
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
| | - Chanhee Kim
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
| | - Giltsu Choi
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
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10
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Du J, Kim K, Chen M. Distinguishing individual photobodies using Oligopaints reveals thermo-sensitive and -insensitive phytochrome B condensation at distinct subnuclear locations. Nat Commun 2024; 15:3620. [PMID: 38684657 PMCID: PMC11058242 DOI: 10.1038/s41467-024-47789-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 04/10/2024] [Indexed: 05/02/2024] Open
Abstract
Photobodies (PBs) are membraneless subnuclear organelles that self-assemble via concentration-dependent liquid-liquid phase separation (LLPS) of the plant photoreceptor and thermosensor phytochrome B (PHYB). The current PHYB LLPS model posits that PHYB phase separates randomly in the nucleoplasm regardless of the cellular or nuclear context. Here, we established a robust Oligopaints method in Arabidopsis to determine the positioning of individual PBs. We show surprisingly that even in PHYB overexpression lines - where PHYB condensation would be more likely to occur randomly - PBs positioned at twelve distinct subnuclear locations distinguishable by chromocenter and nucleolus landmarks, suggesting that PHYB condensation occurs nonrandomly at preferred seeding sites. Intriguingly, warm temperatures reduce PB number by inducing the disappearance of specific thermo-sensitive PBs, demonstrating that individual PBs possess different thermosensitivities. These results reveal a nonrandom PB nucleation model, which provides the framework for the biogenesis of spatially distinct individual PBs with diverse environmental sensitivities within a single plant nucleus.
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Affiliation(s)
- Juan Du
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Keunhwa Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
- Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA.
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11
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Kim RJA, Fan D, He J, Kim K, Du J, Chen M. Photobody formation spatially segregates two opposing phytochrome B signaling actions of PIF5 degradation and stabilization. Nat Commun 2024; 15:3519. [PMID: 38664420 PMCID: PMC11045832 DOI: 10.1038/s41467-024-47790-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
Photoactivation of the plant photoreceptor and thermosensor phytochrome B (PHYB) triggers its condensation into subnuclear membraneless organelles named photobodies (PBs). However, the function of PBs in PHYB signaling remains frustratingly elusive. Here, we found that PHYB recruits PHYTOCHROME-INTERACTING FACTOR 5 (PIF5) to PBs. Surprisingly, PHYB exerts opposing roles in degrading and stabilizing PIF5. Perturbing PB size by overproducing PHYB provoked a biphasic PIF5 response: while a moderate increase in PHYB enhanced PIF5 degradation, further elevating the PHYB level stabilized PIF5 by retaining more of it in enlarged PBs. Conversely, reducing PB size by dim light, which enhanced PB dynamics and nucleoplasmic PHYB and PIF5, switched the balance towards PIF5 degradation. Together, these results reveal that PB formation spatially segregates two antagonistic PHYB signaling actions - PIF5 stabilization in PBs and PIF5 degradation in the surrounding nucleoplasm - which could enable an environmentally sensitive, counterbalancing mechanism to titrate nucleoplasmic PIF5 and environmental responses.
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Affiliation(s)
- Ruth Jean Ae Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - De Fan
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Jiangman He
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Keunhwa Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
- Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Juan Du
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA.
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12
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Kim RJA, Fan D, He J, Kim K, Du J, Chen M. Photobody formation spatially segregates two opposing phytochrome B signaling actions to titrate plant environmental responses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.12.566724. [PMID: 38014306 PMCID: PMC10680666 DOI: 10.1101/2023.11.12.566724] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Photoactivation of the plant photoreceptor and thermosensor phytochrome B (PHYB) triggers its condensation into subnuclear photobodies (PBs). However, the function of PBs remains frustratingly elusive. Here, we found that PHYB recruits PHYTOCHROME-INTERACTING FACTOR5 (PIF5) to PBs. Surprisingly, PHYB exerts opposing roles in degrading and stabilizing PIF5. Perturbing PB size by overproducing PHYB provoked a biphasic PIF5 response: while a moderate increase in PHYB enhanced PIF5 degradation, further elevating the PHYB level stabilized PIF5 by retaining more of it in enlarged PBs. These results reveal a PB-mediated light and temperature sensing mechanism, in which PHYB condensation confers the co-occurrence and competition of two antagonistic phase-separated PHYB signaling actions-PIF5 stabilization in PBs and PIF5 degradation in the surrounding nucleoplasm-thereby enabling an environmentally-sensitive counterbalancing mechanism to titrate nucleoplasmic PIF5 and its transcriptional output. This PB-enabled signaling mechanism provides a framework for regulating a plethora of PHYB-interacting signaling molecules in diverse plant environmental responses.
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Affiliation(s)
- Ruth Jean Ae Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
- These authors contributed equally
| | - De Fan
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
- These authors contributed equally
| | - Jiangman He
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
- These authors contributed equally
| | - Keunhwa Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
- Current address: Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Juan Du
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
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13
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Du J, Chen M. Characterization of Thermoresponsive Photobody Dynamics. Methods Mol Biol 2024; 2795:95-104. [PMID: 38594531 DOI: 10.1007/978-1-0716-3814-9_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Photobodies (PBs) are subnuclear membraneless organelles that self-assemble via the condensation of the plant photoreceptor and thermosensor phytochrome B (phyB). Changes in the light and temperature environment directly modulate PB formation and maintenance by altering the number and size of PBs. In thermomorphogenesis, increases in the ambient temperature incrementally reduce the number of PBs, suggesting that individual PBs possess distinct thermostabilities. Here, we describe a detailed protocol for characterizing cell type-specific PB dynamics induced by warm temperatures in Arabidopsis.
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Affiliation(s)
- Juan Du
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.
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14
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Gao M, Lu Y, Geng F, Klose C, Staudt AM, Huang H, Nguyen D, Lan H, Lu H, Mockler TC, Nusinow DA, Hiltbrunner A, Schäfer E, Wigge PA, Jaeger KE. Phytochromes transmit photoperiod information via the evening complex in Brachypodium. Genome Biol 2023; 24:256. [PMID: 37936225 PMCID: PMC10631206 DOI: 10.1186/s13059-023-03082-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 10/04/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Daylength is a key seasonal cue for animals and plants. In cereals, photoperiodic responses are a major adaptive trait, and alleles of clock genes such as PHOTOPERIOD1 (PPD1) and EARLY FLOWERING3 (ELF3) have been selected for in adapting barley and wheat to northern latitudes. How monocot plants sense photoperiod and integrate this information into growth and development is not well understood. RESULTS We find that phytochrome C (PHYC) is essential for flowering in Brachypodium distachyon. Conversely, ELF3 acts as a floral repressor and elf3 mutants display a constitutive long day phenotype and transcriptome. We find that ELF3 and PHYC occur in a common complex. ELF3 associates with the promoters of a number of conserved regulators of flowering, including PPD1 and VRN1. Consistent with observations in barley, we are able to show that PPD1 overexpression accelerates flowering in short days and is necessary for rapid flowering in response to long days. PHYC is in the active Pfr state at the end of the day, but we observe it undergoes dark reversion over the course of the night. CONCLUSIONS We propose that PHYC acts as a molecular timer and communicates information on night-length to the circadian clock via ELF3.
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Affiliation(s)
- Mingjun Gao
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Yunlong Lu
- Leibniz-Institut für Gemüse- und Zierpflanzenbau, Theodor-Echtermeyer-Weg 1, Großbeeren, 14979, Germany
| | - Feng Geng
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK
| | - Cornelia Klose
- Institut für Biologie II, University of Freiburg, Schaenzlestr. 1, Freiburg, 79104, Germany
| | - Anne-Marie Staudt
- Institut für Biologie II, University of Freiburg, Schaenzlestr. 1, Freiburg, 79104, Germany
| | - He Huang
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Duy Nguyen
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK
| | - Hui Lan
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK
| | - Han Lu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Todd C Mockler
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | | | - Andreas Hiltbrunner
- Institut für Biologie II, University of Freiburg, Schaenzlestr. 1, Freiburg, 79104, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, 79104, Germany
| | - Eberhard Schäfer
- Institut für Biologie II, University of Freiburg, Schaenzlestr. 1, Freiburg, 79104, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schaenzlestr. 18, Freiburg, 79104, Germany
| | - Philip A Wigge
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK.
- Leibniz-Institut für Gemüse- und Zierpflanzenbau, Theodor-Echtermeyer-Weg 1, Großbeeren, 14979, Germany.
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, 14476, Germany.
| | - Katja E Jaeger
- Sainsbury Laboratory, University of Cambridge, 47 Bateman St., Cambridge, CB2 1LR, UK.
- Leibniz-Institut für Gemüse- und Zierpflanzenbau, Theodor-Echtermeyer-Weg 1, Großbeeren, 14979, Germany.
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15
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Rodríguez-Bolaños M, Martínez T, Juárez S, Quiroz S, Domínguez A, Garay-Arroyo A, Sanchez MDLP, Álvarez-Buylla ER, García-Ponce B. XAANTAL1 Reveals an Additional Level of Flowering Regulation in the Shoot Apical Meristem in Response to Light and Increased Temperature in Arabidopsis. Int J Mol Sci 2023; 24:12773. [PMID: 37628953 PMCID: PMC10454237 DOI: 10.3390/ijms241612773] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Light and photoperiod are environmental signals that regulate flowering transition. In plants like Arabidopsis thaliana, this regulation relies on CONSTANS, a transcription factor that is negatively posttranslational regulated by phytochrome B during the morning, while it is stabilized by PHYA and cryptochromes 1/2 at the end of daylight hours. CO induces the expression of FT, whose protein travels from the leaves to the apical meristem, where it binds to FD to regulate some flowering genes. Although PHYB delays flowering, we show that light and PHYB positively regulate XAANTAL1 and other flowering genes in the shoot apices. Also, the genetic data indicate that XAL1 and FD participate in the same signaling pathway in flowering promotion when plants are grown under a long-day photoperiod at 22 °C. By contrast, XAL1 functions independently of FD or PIF4 to induce flowering at higher temperatures (27 °C), even under long days. Furthermore, XAL1 directly binds to FD, SOC1, LFY, and AP1 promoters. Our findings lead us to propose that light and temperature influence the floral network at the meristem level in a partially independent way of the signaling generated from the leaves.
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Affiliation(s)
- Mónica Rodríguez-Bolaños
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Tania Martínez
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Saray Juárez
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Stella Quiroz
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
- Laboratory of Pathogens and Host Immunity, University of Montpellier, 34 090 Montpellier, France
| | - Andrea Domínguez
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Adriana Garay-Arroyo
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - María de la Paz Sanchez
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Elena R. Álvarez-Buylla
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
| | - Berenice García-Ponce
- Instituto de Ecologίa, Departamento de Ecologίa Funcional, Universidad Nacional Autónoma de México, Circuito ext. s/no. Ciudad Universitaria, Coyoacán 04510, CDMX, Mexico
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16
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Peng KC, Siao W, Hsieh HL. FAR-RED INSENSITIVE 219 and phytochrome B corepress shade avoidance via modulating nuclear speckle formation. PLANT PHYSIOLOGY 2023; 192:1449-1465. [PMID: 36869668 PMCID: PMC10231371 DOI: 10.1093/plphys/kiad103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 11/22/2022] [Accepted: 11/22/2022] [Indexed: 06/01/2023]
Abstract
Plants can sense the shade from neighboring plants by detecting a reduction of the red:far-red light (R:FR) ratio. Phytochrome B (phyB) is the primary photoreceptor that perceives shade light and regulates jasmonic acid (JA) signaling. However, the molecular mechanisms underlying phyB and JA signaling integration in shade responses remain largely unknown. Here, we show the interaction of phyB and FAR-RED INSENSITIVE 219 (FIN219)/JASMONATE RESISTANT1 (JAR1) in a functional demand manner in Arabidopsis (Arabidopsis thaliana) seedling development. Genetic evidence and interaction studies indicated that phyB and FIN219 synergistically and negatively regulate shade-induced hypocotyl elongation. Moreover, phyB interacted with various isoforms of FIN219 under high and low R:FR light. Methyl jasmonate (MeJA) treatment, FIN219 mutation, and PHYBOE digalactosyldiacylglycerol synthase1-1 (dgd1-1) plants, which show increased levels of JA, altered the patterns of phyB-associated nuclear speckles under the same conditions. Surprisingly, PHYBOE dgd1-1 showed a shorter hypocotyl phenotype than its parental mutants under shade conditions. Microarray assays using PHYBOE and PHYBOE fin219-2 indicated that PHYB overexpression substantially affects defense response-related genes under shade light and coregulates expression of auxin-responsive genes with FIN219. Thus, our findings reveal that phyB substantially crosstalks with JA signaling through FIN219 to modulate seedling development under shade light.
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Affiliation(s)
- Kai-Chun Peng
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei 106, Taiwan
| | - Wei Siao
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei 106, Taiwan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Hsu-Liang Hsieh
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei 106, Taiwan
- Department of Life Science, College of Life Science, National Taiwan University, Taipei 106, Taiwan
- Master Program in Global Agriculture Technology and Genomic Science, National Taiwan University, Taipei 106, Taiwan
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17
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Krupnik T, Zienkiewicz M, Wasilewska-Dębowska W, Drożak A, Kania K. How Light Modulates the Growth of Cyanidioschyzon merolae Cells by Changing the Function of Phycobilisomes. Cells 2023; 12:1480. [PMID: 37296601 PMCID: PMC10252272 DOI: 10.3390/cells12111480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/18/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
The aim of this study was to examine how light intensity and quality affect the photosynthetic apparatus of Cyanidioschyzon merolae cells by modulating the structure and function of phycobilisomes. Cells were grown in equal amounts of white, blue, red, and yellow light of low (LL) and high (HL) intensity. Biochemical characterization, fluorescence emission, and oxygen exchange were used to investigate selected cellular physiological parameters. It was found that the allophycocyanin content was sensitive only to light intensity, whereas the phycocynin content was also sensitive to light quality. Furthermore, the concentration of the PSI core protein was not affected by the intensity or quality of the growth light, but the concentration of the PSII core D1 protein was. Finally, the amount of ATP and ADP was lower in HL than LL. In our opinion, both light intensity and quality are main factors that play an important regulatory role in acclimatization/adaptation of C. merolae to environmental changes, and this is achieved by balancing the amounts of thylakoid membrane and phycobilisome proteins, the energy level, and the photosynthetic and respiratory activity. This understanding contributes to the development of a mix of cultivation techniques and genetic changes for a future large-scale synthesis of desirable biomolecules.
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Affiliation(s)
- Tomasz Krupnik
- Department of Molecular Plant Physiology, Institute of Environmental Biology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02096 Warsaw, Poland
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18
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Sorkin ML, Tzeng SC, King S, Romanowski A, Kahle N, Bindbeutel R, Hiltbrunner A, Yanovsky MJ, Evans BS, Nusinow DA. COLD REGULATED GENE 27 and 28 Antagonize the Transcriptional Activity of the RVE8/LNK1/LNK2 Circadian Complex. PLANT PHYSIOLOGY 2023:kiad210. [PMID: 37017001 DOI: 10.1093/plphys/kiad210] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 03/01/2023] [Accepted: 04/04/2023] [Indexed: 06/19/2023]
Abstract
Many molecular and physiological processes in plants occur at a specific time of day. These daily rhythms are coordinated in part by the circadian clock, a timekeeper that uses daylength and temperature to maintain rhythms of approximately 24 hours in various clock-regulated phenotypes. The circadian MYB-like transcription factor REVEILLE 8 (RVE8) interacts with its transcriptional coactivators NIGHT LIGHT INDUCIBLE AND CLOCK REGULATED 1 (LNK1) and LNK2 to promote the expression of evening-phased clock genes and cold tolerance factors. While genetic approaches have commonly been used to discover connections within the clock and between clock elements and other pathways, here we used affinity purification coupled with mass spectrometry to identify time-of-day-specific protein interactors of the RVE8-LNK1/LNK2 complex in Arabidopsis (Arabidopsis thaliana). Among the interactors of RVE8/LNK1/LNK2 were COLD REGULATED GENE 27 (COR27) and COR28, which coprecipitated in an evening-specific manner. In addition to COR27 and COR28, we found an enrichment of temperature-related interactors that led us to establish a previously uncharacterized role for LNK1 and LNK2 in temperature entrainment of the clock. We established that RVE8, LNK1, and either COR27 or COR28 form a tripartite complex in yeast (Saccharomyces cerevisiae) and that the effect of this interaction in planta serves to antagonize transcriptional activation of RVE8 target genes, potentially through mediating RVE8 protein degradation in the evening. Together, these results illustrate how a proteomic approach can be used to identify time-of-day-specific protein interactions. Discovery of the RVE8-LNK-COR protein complex indicates a previously unknown regulatory mechanism for circadian and temperature signaling pathways.
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Affiliation(s)
- Maria L Sorkin
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | | | - Stefanie King
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Andrés Romanowski
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Nikolai Kahle
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | | | - Andreas Hiltbrunner
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Marcelo J Yanovsky
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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19
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Kim H, Kim J, Choi G. Epidermal phyB requires RRC1 to promote light responses by activating the circadian rhythm. THE NEW PHYTOLOGIST 2023; 238:705-723. [PMID: 36651061 DOI: 10.1111/nph.18746] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 12/30/2022] [Indexed: 06/17/2023]
Abstract
Phytochrome B (phyB) expressed in the epidermis is sufficient to promote red light responses, including the inhibition of hypocotyl elongation and hypocotyl negative gravitropism. Nonetheless, the downstream mechanism of epidermal phyB in promoting light responses had been elusive. Here, we mutagenized the epidermis-specific phyB-expressing line (MLB) using ethyl methanesulfonate (EMS) and characterized a novel mutant allele of RRC1 (rrc1-689), which causes reduced epidermal phyB-mediated red light responses. The rrc1-689 mutation increases the alternative splicing of major clock gene transcripts, including PRR7 and TOC1, disrupting the rhythmic expression of the entire clock and clock-controlled genes. Combined with the result that MLB/prr7 exhibits the same red-hyposensitive phenotypes as MLB/rrc1-689, our data support that the circadian clock is required for the ability of epidermal phyB to promote light responses. We also found that, unlike phyB, RRC1 preferentially acts in the endodermis to maintain the circadian rhythm by suppressing the alternative splicing of core clock genes. Together, our results suggest that epidermal phyB requires RRC1 to promote light responses by activating the circadian rhythm in Arabidopsis thaliana.
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Affiliation(s)
- Hanim Kim
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
| | - Jaewook Kim
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
| | - Giltsu Choi
- Department of Biological Sciences, KAIST, Daejeon, 34141, Korea
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20
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Kim C, Kwon Y, Jeong J, Kang M, Lee GS, Moon JH, Lee HJ, Park YI, Choi G. Phytochrome B photobodies are comprised of phytochrome B and its primary and secondary interacting proteins. Nat Commun 2023; 14:1708. [PMID: 36973259 PMCID: PMC10042835 DOI: 10.1038/s41467-023-37421-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 03/16/2023] [Indexed: 03/29/2023] Open
Abstract
Phytochrome B (phyB) is a plant photoreceptor that forms a membraneless organelle called a photobody. However, its constituents are not fully known. Here, we isolated phyB photobodies from Arabidopsis leaves using fluorescence-activated particle sorting and analyzed their components. We found that a photobody comprises ~1,500 phyB dimers along with other proteins that could be classified into two groups: The first includes proteins that directly interact with phyB and localize to the photobody when expressed in protoplasts, while the second includes proteins that interact with the first group proteins and require co-expression of a first-group protein to localize to the photobody. As an example of the second group, TOPLESS interacts with PHOTOPERIODIC CONTROL OF HYPOCOTYL 1 (PCH1) and localizes to the photobody when co-expressed with PCH1. Together, our results support that phyB photobodies include not only phyB and its primary interacting proteins but also its secondary interacting proteins.
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Affiliation(s)
- Chanhee Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Yongmin Kwon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Jaehoon Jeong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Minji Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Ga Seul Lee
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 34141, Korea
- College of Pharmacy, Chungbuk National University, Cheongju, Chungbuk, 28160, Korea
| | - Jeong Hee Moon
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 34141, Korea
| | - Hyo-Jun Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 34141, Korea
| | - Youn-Il Park
- Department of Biological Sciences, Chungnam National University, Daejeon, 34134, Korea
| | - Giltsu Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea.
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21
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Sorkin ML, Markham KK, Zorich S, Menon A, Edgeworth KN, Ricono A, Bryant D, Bart R, Nusinow DA, Greenham K. Assembly and operation of an imaging system for long-term monitoring of bioluminescent and fluorescent reporters in plants. PLANT METHODS 2023; 19:19. [PMID: 36859301 PMCID: PMC9976486 DOI: 10.1186/s13007-023-00997-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Non-invasive reporter systems are powerful tools to query physiological and transcriptional responses in organisms. For example, fluorescent and bioluminescent reporters have revolutionized cellular and organismal assays and have been used to study plant responses to abiotic and biotic stressors. Integrated, cooled charge-coupled device (CCD) camera systems have been developed to image bioluminescent and fluorescent signals in a variety of organisms; however, these integrated long-term imaging systems are expensive. RESULTS We have developed self-assembled systems for both growing and monitoring plant fluorescence and bioluminescence for long-term experiments under controlled environmental conditions. This system combines environmental growth chambers with high-sensitivity CCD cameras, multi-wavelength LEDs, open-source software, and several options for coordinating lights with imaging. This easy-to-assemble system can be used for short and long-term imaging of bioluminescent reporters, acute light-response, circadian rhythms, delayed fluorescence, and fluorescent-protein-based assays in vivo. CONCLUSIONS We have developed two self-assembled imaging systems that will be useful to researchers interested in continuously monitoring in vivo reporter systems in various plant species.
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Affiliation(s)
- Maria L Sorkin
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Department of Biological and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | | | | | | | - Kristen N Edgeworth
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Department of Biological and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | | | - Douglas Bryant
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- NewLeaf Symbiotics, St Louis, MO, USA
| | - Rebecca Bart
- Donald Danforth Plant Science Center, St. Louis, MO, USA
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22
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Fang W, Vellutini E, Perrella G, Kaiserli E. TANDEM ZINC-FINGER/PLUS3 regulates phytochrome B abundance and signaling to fine-tune hypocotyl growth. THE PLANT CELL 2022; 34:4213-4231. [PMID: 35929801 PMCID: PMC9614508 DOI: 10.1093/plcell/koac236] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/28/2022] [Indexed: 05/19/2023]
Abstract
TANDEM ZINC-FINGER/PLUS3 (TZP) is a transcriptional regulator that acts at the crossroads of light and photoperiodic signaling. Here, we unveil a role for TZP in fine-tuning hypocotyl elongation under red light and long-day conditions. We provide genetic evidence for a synergistic action between TZP and PHOTOPERIODIC CONTROL OF HYPOCOTYL 1 (PCH1) in regulating the protein abundance of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and downstream gene expression in response to red light and long days (LDs). Furthermore, we show that TZP is a positive regulator of the red/far-red light receptor and thermosensor phytochrome B (phyB) by promoting phyB protein abundance, nuclear body formation, and signaling. Our data therefore assign a function to TZP in regulating two key red light signaling components, phyB and PIF4, but also uncover a new role for PCH1 in regulating hypocotyl elongation in LDs. Our findings provide a framework for the understanding of the mechanisms associated with the TZP signal integration network and their importance for optimizing plant growth and adaptation to a changing environment.
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Affiliation(s)
- Weiwei Fang
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Elisa Vellutini
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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23
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Oravec MW, Greenham K. The adaptive nature of the plant circadian clock in natural environments. PLANT PHYSIOLOGY 2022; 190:968-980. [PMID: 35894658 PMCID: PMC9516730 DOI: 10.1093/plphys/kiac337] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 06/27/2022] [Indexed: 05/10/2023]
Abstract
The plant circadian clock coordinates developmental, physiological, and metabolic processes with diel changes in light and temperature throughout the year. The balance between the persistence and plasticity of the clock in response to predictable and unpredictable environmental changes may be key to the clock's adaptive nature across temporal and spatial scales. Studies under controlled conditions have uncovered critical signaling pathways involved in light and temperature perception by the clock; however, they don't account for the natural lag of temperature behind photoperiod. Studies in natural environments provide key insights into the clock's adaptive advantage under more complex natural settings. Here, we discuss the role of the circadian clock in light and temperature perception and signaling, how the clock integrates these signals for a coordinated and adaptive response, and the adaptive advantage conferred by the clock across time and space in natural environments.
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Affiliation(s)
- Madeline W Oravec
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota 55108, USA
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24
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Li X, Liang T, Liu H. How plants coordinate their development in response to light and temperature signals. THE PLANT CELL 2022; 34:955-966. [PMID: 34904672 PMCID: PMC8894937 DOI: 10.1093/plcell/koab302] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 12/06/2021] [Indexed: 05/12/2023]
Abstract
Light and temperature change constantly under natural conditions and profoundly affect plant growth and development. Light and warmer temperatures promote flowering, higher light intensity inhibits hypocotyl and petiole elongation, and warmer temperatures promote hypocotyl and petiole elongation. Moreover, exogenous light and temperature signals must be integrated with endogenous signals to fine-tune phytohormone metabolism and plant morphology. Plants perceive and respond to light and ambient temperature using common sets of factors, such as photoreceptors and multiple light signal transduction components. These highly structured signaling networks are critical for plant survival and adaptation. This review discusses how plants respond to variable light and temperature conditions using common elements to coordinate their development. Future directions for research on light and temperature signaling pathways are also discussed.
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Affiliation(s)
- Xu Li
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Tong Liang
- Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA
| | - Hongtao Liu
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
- Author for correspondence:
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Xu X, Zheng C, Lu D, Song CP, Zhang L. Phase separation in plants: New insights into cellular compartmentalization. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:1835-1855. [PMID: 34314106 DOI: 10.1111/jipb.13152] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/16/2021] [Indexed: 05/16/2023]
Abstract
A fundamental challenge for cells is how to coordinate various biochemical reactions in space and time. To achieve spatiotemporal control, cells have developed organelles that are surrounded by lipid bilayer membranes. Further, membraneless compartmentalization, a process induced by dynamic physical association of biomolecules through phase transition offers another efficient mechanism for intracellular organization. While our understanding of phase separation was predominantly dependent on yeast and animal models, recent findings have provided compelling evidence for emerging roles of phase separation in plants. In this review, we first provide an overview of the current knowledge of phase separation, including its definition, biophysical principles, molecular features and regulatory mechanisms. Then we summarize plant-specific phase separation phenomena and describe their functions in plant biological processes in great detail. Moreover, we propose that phase separation is an evolutionarily conserved and efficient mechanism for cellular compartmentalization which allows for distinct metabolic processes and signaling pathways, and is especially beneficial for the sessile lifestyle of plants to quickly and efficiently respond to the changing environment.
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Affiliation(s)
- Xiumei Xu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Canhui Zheng
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Dandan Lu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Chun-Peng Song
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
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Pardi SA, Nusinow DA. Out of the Dark and Into the Light: A New View of Phytochrome Photobodies. FRONTIERS IN PLANT SCIENCE 2021; 12:732947. [PMID: 34531891 PMCID: PMC8438518 DOI: 10.3389/fpls.2021.732947] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/05/2021] [Indexed: 05/27/2023]
Abstract
Light is a critical environmental stimulus for plants, serving as an energy source via photosynthesis and a signal for developmental programming. Plants perceive light through various light-responsive proteins, termed photoreceptors. Phytochromes are red-light photoreceptors that are highly conserved across kingdoms. In the model plant Arabidopsis thaliana, phytochrome B serves as a light and thermal sensor, mediating physiological processes such as seedling germination and establishment, hypocotyl growth, chlorophyll biogenesis, and flowering. In response to red light, phytochromes convert to a biologically active form, translocating from the cytoplasm into the nucleus and further compartmentalizes into subnuclear compartments termed photobodies. PhyB photobodies regulate phytochrome-mediated signaling and physiological outputs. However, photobody function, composition, and biogenesis remain undefined since their discovery. Based on photobody cellular dynamics and the properties of internal components, photobodies have been suggested to undergo liquid-liquid phase separation, a process by which some membraneless compartments form. Here, we explore photobodies as environmental sensors, examine the role of their protein constituents, and outline the biophysical perspective that photobodies may be undergoing liquid-liquid phase separation. Understanding the molecular, cellular, and biophysical processes that shape how plants perceive light will help in engineering improved sunlight capture and fitness of important crops.
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Affiliation(s)
- Sarah A. Pardi
- Donald Danforth Plant Science Center, St. Louis, MO, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, United States
| | - Dmitri A. Nusinow
- Donald Danforth Plant Science Center, St. Louis, MO, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, United States
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Abstract
In rice, a small increase in nighttime temperature reduces grain yield and quality. How warm nighttime temperatures (WNT) produce these detrimental effects is not well understood, especially in field conditions where the typical day-to-night temperature fluctuation exceeds the mild increase in nighttime temperature. We observed genome-wide disruption of gene expression timing during the reproductive phase in field-grown rice panicles acclimated to 2 to 3 °C WNT. Transcripts previously identified as rhythmically expressed with a 24-h period and circadian-regulated transcripts were more sensitive to WNT than were nonrhythmic transcripts. The system-wide perturbations in transcript levels suggest that WNT disrupt the tight temporal coordination between internal molecular events and the environment, resulting in reduced productivity. We identified transcriptional regulators whose predicted targets are enriched for sensitivity to WNT. The affected transcripts and candidate regulators identified through our network analysis explain molecular mechanisms driving sensitivity to WNT and identify candidates that can be targeted to enhance tolerance to WNT.
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Abstract
The perception of light signals by the phytochrome family of photoreceptors has a crucial influence on almost all aspects of growth and development throughout a plant's life cycle. The holistic regulatory networks orchestrated by phytochromes, including conformational switching, subcellular localization, direct protein-protein interactions, transcriptional and posttranscriptional regulations, and translational and posttranslational controls to promote photomorphogenesis, are highly coordinated and regulated at multiple levels. During the past decade, advances using innovative approaches have substantially broadened our understanding of the sophisticated mechanisms underlying the phytochrome-mediated light signaling pathways. This review discusses and summarizes these discoveries of the role of the modular structure of phytochromes, phytochrome-interacting proteins, and their functions; the reciprocal modulation of both positive and negative regulators in phytochrome signaling; the regulatory roles of phytochromes in transcriptional activities, alternative splicing, and translational regulation; and the kinases and E3 ligases that modulate PHYTOCHROME INTERACTING FACTORs to optimize photomorphogenesis.
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Affiliation(s)
- Mei-Chun Cheng
- Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA;
| | - Praveen Kumar Kathare
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA;
| | - Inyup Paik
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA;
| | - Enamul Huq
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA;
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29
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Mehta D, Krahmer J, Uhrig RG. Closing the protein gap in plant chronobiology. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:1509-1522. [PMID: 33783885 DOI: 10.1111/tpj.15254] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 06/12/2023]
Abstract
Our modern understanding of diel cell regulation in plants stems from foundational work in the late 1990s that analysed the dynamics of selected genes and mutants in Arabidopsis thaliana. The subsequent rise of transcriptomics technologies such as microarrays and RNA sequencing has substantially increased our understanding of anticipatory (circadian) and reactive (light- or dark-triggered) diel events in plants. However, it is also becoming clear that gene expression data fail to capture critical events in diel regulation that can only be explained by studying protein-level dynamics. Over the past decade, mass spectrometry technologies and quantitative proteomic workflows have significantly advanced, finally allowing scientists to characterise diel protein regulation at high throughput. Initial proteomic investigations suggest that the diel transcriptome and proteome generally lack synchrony and that the timing of daily regulatory events in plants is impacted by multiple levels of protein regulation (e.g., post-translational modifications [PTMs] and protein-protein interactions [PPIs]). Here, we highlight and summarise how the use of quantitative proteomics to elucidate diel plant cell regulation has advanced our understanding of these processes. We argue that this new understanding, coupled with the extraordinary developments in mass spectrometry technologies, demands greater focus on protein-level regulation of, and by, the circadian clock. This includes hitherto unexplored diel dynamics of protein turnover, PTMs, protein subcellular localisation and PPIs that can be masked by simple transcript- and protein-level changes. Finally, we propose new directions for how the latest advancements in quantitative proteomics can be utilised to answer outstanding questions in plant chronobiology.
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Affiliation(s)
- Devang Mehta
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Johanna Krahmer
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - R Glen Uhrig
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
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Hernando CE, Murcia MG, Pereyra ME, Sellaro R, Casal JJ. Phytochrome B links the environment to transcription. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4068-4084. [PMID: 33704448 DOI: 10.1093/jxb/erab037] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
Phytochrome B (phyB) senses the difference between darkness and light, the level of irradiance, the red/far-red ratio, and temperature. Thanks to these sensory capacities, phyB perceives whether plant organs are buried in the soil, exposed to full sunlight, in the presence of nearby vegetation, and/or under risk of heat stress. In some species, phyB perceives seasonal daylength cues. phyB affects the activity of several transcriptional regulators either by direct physical interaction or indirectly by physical interaction with proteins involved in the turnover of transcriptional regulators. Typically, interaction of a protein with phyB has either negative or positive effects on the interaction of the latter with a third party, this being another protein or DNA. Thus, phyB mediates the context-dependent modulation of the transcriptome underlying changes in plant morphology, physiology, and susceptibility to biotic and abiotic stress. phyB operates as a dynamic switch that improves carbon balance, prioritizing light interception and photosynthetic capacity in open places and the projection of the shoot towards light in the soil, under shade and in warm conditions.
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Affiliation(s)
- Carlos Esteban Hernando
- Fundación Instituto Leloir and IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - Mauro Germán Murcia
- Fundación Instituto Leloir and IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - Matías Ezequiel Pereyra
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Av. San Martín 4453, Buenos Aires C1417DSE, Argentina
| | - Romina Sellaro
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Av. San Martín 4453, Buenos Aires C1417DSE, Argentina
| | - Jorge José Casal
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Av. San Martín 4453, Buenos Aires C1417DSE, Argentina
- Fundación Instituto Leloir and IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
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Bruessow F, Bautor J, Hoffmann G, Yildiz I, Zeier J, Parker JE. Natural variation in temperature-modulated immunity uncovers transcription factor bHLH059 as a thermoresponsive regulator in Arabidopsis thaliana. PLoS Genet 2021; 17:e1009290. [PMID: 33493201 PMCID: PMC7861541 DOI: 10.1371/journal.pgen.1009290] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/04/2021] [Accepted: 11/10/2020] [Indexed: 01/31/2023] Open
Abstract
Temperature impacts plant immunity and growth but how temperature intersects with endogenous pathways to shape natural variation remains unclear. Here we uncover variation between Arabidopsis thaliana natural accessions in response to two non-stress temperatures (22°C and 16°C) affecting accumulation of the thermoresponsive stress hormone salicylic acid (SA) and plant growth. Analysis of differentially responding A. thaliana accessions shows that pre-existing SA provides a benefit in limiting infection by Pseudomonas syringae pathovar tomato DC3000 bacteria at both temperatures. Several A. thaliana genotypes display a capacity to mitigate negative effects of high SA on growth, indicating within-species plasticity in SA—growth tradeoffs. An association study of temperature x SA variation, followed by physiological and immunity phenotyping of mutant and over-expression lines, identifies the transcription factor bHLH059 as a temperature-responsive SA immunity regulator. Here we reveal previously untapped diversity in plant responses to temperature and a way forward in understanding the genetic architecture of plant adaptation to changing environments. Temperature has a profound effect on plant innate immune responses but little is known about the mechanisms underlying natural variation in transmission of temperature signals to defence pathways. Much of our understanding of temperature effects on plant immunity and tradeoffs between activated defences and growth has come from analysis of the common Arabidopsis thaliana genetic accession, Col-0. Here we examine A. thaliana genetic variation in response to temperature (within the non-stress range—22 oC and 16 oC) at the level of accumulation of the thermoresponsive biotic stress hormone salicylic acid (SA), bacterial pathogen resistance, and plant biomass. From analysis of 105 genetically diverse A. thaliana accessions we uncover plasticity in temperature-modulated SA homeostasis and in the relationship between SA levels and plant growth. We find that high SA amounts prior to infection provide a robust benefit of enhancing bacterial resistance. In some accessions this benefit comes without compromised plant growth, suggestive of altered defence–growth tradeoffs. Based on a temperature x SA association study we identify the transcription factor gene, bHLH059, and show that it has features of a temperature-sensitive immunity regulator that are unrelated to PIF4, a known thermosensitive coordinator of immunity and growth.
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Affiliation(s)
- Friederike Bruessow
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Cologne, Germany
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), Düsseldorf, Germany
| | - Jaqueline Bautor
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Gesa Hoffmann
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Ipek Yildiz
- Institute of Plant Molecular Ecophysiology, Heinrich Heine University, Düsseldorf, Germany
| | - Jürgen Zeier
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), Düsseldorf, Germany
- Institute of Plant Molecular Ecophysiology, Heinrich Heine University, Düsseldorf, Germany
| | - Jane E. Parker
- Department of Plant-Microbe Interactions, Max-Planck Institute for Plant Breeding Research, Cologne, Germany
- Cologne-Düsseldorf Cluster of Excellence on Plant Sciences (CEPLAS), Düsseldorf, Germany
- * E-mail:
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32
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Perrella G, Zioutopoulou A, Hamilton A, Kaiserli E. Photobody Detection Using Immunofluorescence and Super-Resolution Imaging in Arabidopsis. Methods Mol Biol 2021; 2297:7-19. [PMID: 33656665 DOI: 10.1007/978-1-0716-1370-2_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Light triggers changes in plant nuclear architecture to control differentiation, adaptation, and growth. A series of genetic, molecular, and imaging approaches have revealed that the nucleus forms a hub for photo-induced protein interactions and gene regulatory events. However, the mechanism and function of light-induced nuclear compartmentalization is still unclear. This chapter provides detailed experimental protocols for examining the morphology and potential functional significance of light signaling components that localize in light-induced subnuclear domains, also known as photobodies. We describe how immunolabeling of endogenous proteins and fluorescent in situ hybridization (FISH) could be combined with confocal imaging of fluorescently tagged proteins to assess co-localization in Arabidopsis nuclei. Furthermore, we employ a super-resolution imaging approach to study the morphology of photobodies at unprecedented detail.
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Affiliation(s)
- Giorgio Perrella
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, Scotland, UK.,ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Trisaia Research Center, Rotondella, Italy
| | - Anna Zioutopoulou
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, Scotland, UK
| | - Andrew Hamilton
- School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, Scotland, UK
| | - Eirini Kaiserli
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, Scotland, UK.
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Murcia G, Enderle B, Hiltbrunner A, Casal JJ. Phytochrome B and PCH1 protein dynamics store night temperature information. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:22-33. [PMID: 33098600 DOI: 10.1111/tpj.15034] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 09/11/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
Plants experience temperature fluctuations during the course of the daily cycle, and although stem growth responds rapidly to these changes we largely ignore whether there is a short-term memory of previous conditions. Here we show that nighttime temperatures affect the growth of the hypocotyl of Arabidopsis thaliana seedlings not only during the night but also during the subsequent photoperiod. Active phytochrome B (phyB) represses nighttime growth and warm temperatures reduce active phyB via thermal reversion. The function of PHOTOPERIODIC CONTROL OF HYPOCOTYL1 (PCH1) is to stabilise active phyB in nuclear bodies but, surprisingly, warmth reduces PCH1 gene expression and PCH1 stability. When phyB was active at the beginning of the night, warm night temperatures enhanced the levels of nuclear phyB and reduced hypocotyl growth rate during the following day. However, when end-of-day far-red light minimised phyB activity, warm night temperatures reduced the levels of nuclear phyB and enhanced the hypocotyl growth rate during the following day. This complex growth pattern was absent in the phyB mutant. We propose that temperature-induced changes in the levels of PCH1 and in the size of the physiologically relevant nuclear pool of phyB amplify the impact of phyB-mediated temperature sensing.
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Affiliation(s)
- Germán Murcia
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-CONICET, Av. Patricias Argentinas 435, Buenos Aires, C1405BWE, Argentina
| | - Beatrix Enderle
- Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, Freiburg, 79104, Germany
| | - Andreas Hiltbrunner
- Institute of Biology II, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, Freiburg, 79104, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, Freiburg, 79104, Germany
| | - Jorge J Casal
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-CONICET, Av. Patricias Argentinas 435, Buenos Aires, C1405BWE, Argentina
- Facultad de Agronomía, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Av. San Martín 4453, Buenos Aires, 1417, Argentina
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34
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Meyer HM. In search of function: nuclear bodies and their possible roles as plant environmental sensors. CURRENT OPINION IN PLANT BIOLOGY 2020; 58:33-40. [PMID: 33181404 DOI: 10.1016/j.pbi.2020.10.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/15/2020] [Accepted: 10/01/2020] [Indexed: 05/02/2023]
Abstract
Plants must adjust their physiology, development and reproductive decisions in response to a fluctuating environment. Understanding how these adjustments are achieved is fundamental for predicting plant reactions to global environmental changes and for designing mitigation strategies. An often overlooked plant-environmental response is the formation of intranuclear membrane-less organelles known as 'nuclear bodies'. Currently, the functional role of nuclear bodies remains largely unclear. However, in recent years, they have received increased attention as possible hubs or integrators of environmental signals, and for possibly being part of the sensing machinery itself. Here, we will explore the formation of nuclear bodies under changing light, osmotic, and temperature conditions. We will then hypothesize on their potential functions in facilitating environmentally driven plant responses.
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Affiliation(s)
- Heather M Meyer
- Carnegie Institution for Science - Department of Plant Biology, 260 Panama Street, Stanford, CA 94305, USA.
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35
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Emenecker RJ, Holehouse AS, Strader LC. Emerging Roles for Phase Separation in Plants. Dev Cell 2020; 55:69-83. [PMID: 33049212 PMCID: PMC7577370 DOI: 10.1016/j.devcel.2020.09.010] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/19/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022]
Abstract
The plant cell internal environment is a dynamic, intricate landscape composed of many intracellular compartments. Cells organize some cellular components through formation of biomolecular condensates-non-stoichiometric assemblies of protein and/or nucleic acids. In many cases, phase separation appears to either underly or contribute to the formation of biomolecular condensates. Many canonical membraneless compartments within animal cells form in a manner that is at least consistent with phase separation, including nucleoli, stress granules, Cajal bodies, and numerous additional bodies, regulated by developmental and environmental stimuli. In this Review, we examine the emerging roles for phase separation in plants. Further, drawing on studies carried out in other organisms, we identify cellular phenomenon in plants that might also arise via phase separation. We propose that plants make use of phase separation to a much greater extent than has been previously appreciated, implicating phase separation as an evolutionarily ancient mechanism for cellular organization.
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Affiliation(s)
- Ryan J Emenecker
- Department of Biology, Washington University, St. Louis, MO 63130, USA; Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA; Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA.
| | - Lucia C Strader
- Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA; Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA; Department of Biology, Duke University, Durham, NC 27708, USA.
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36
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Kim C, Kim SJ, Jeong J, Park E, Oh E, Park YI, Lim PO, Choi G. High Ambient Temperature Accelerates Leaf Senescence via PHYTOCHROME-INTERACTING FACTOR 4 and 5 in Arabidopsis. Mol Cells 2020; 43:645-661. [PMID: 32732458 PMCID: PMC7398796 DOI: 10.14348/molcells.2020.0117] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/10/2020] [Accepted: 06/10/2020] [Indexed: 11/30/2022] Open
Abstract
Leaf senescence is a developmental process by which a plant actively remobilizes nutrients from aged and photosynthetically inefficient leaves to young growing ones by disassembling organelles and degrading macromolecules. Senescence is accelerated by age and environmental stresses such as prolonged darkness. Phytochrome B (phyB) inhibits leaf senescence by inhibiting phytochrome-interacting factor 4 (PIF4) and PIF5 in prolonged darkness. However, it remains unknown whether phyB mediates the temperature signal that regulates leaf senescence. We found the light-activated form of phyB (Pfr) remains active at least four days after a transfer to darkness at 20°C but is inactivated more rapidly at 28°C. This faster inactivation of Pfr further increases PIF4 protein levels at the higher ambient temperature. In addition, PIF4 mRNA levels rise faster after the transfer to darkness at high ambient temperature via a mechanism that depends on ELF3 but not phyB. Increased PIF4 protein then binds to the ORE1 promoter and activates its expression together with ABA and ethylene signaling, accelerating leaf senescence at high ambient temperature. Our results support a role for the phy-PIF signaling module in integrating not only light signaling but also temperature signaling in the regulation of leaf senescence.
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Affiliation(s)
- Chanhee Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 344, Korea
| | - Sun Ji Kim
- Center for Plant Aging Research, Institute for Basic Science, Daegu 4988, Korea
| | - Jinkil Jeong
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 9207, USA
| | - Eunae Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 344, Korea
| | - Eunkyoo Oh
- Division of Life Sciences, Korea University, Seoul 0281, Korea
| | - Youn-Il Park
- Department of Biological Sciences and Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Korea
| | - Pyung Ok Lim
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea
| | - Giltsu Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 344, Korea
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37
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Hahm J, Kim K, Qiu Y, Chen M. Increasing ambient temperature progressively disassembles Arabidopsis phytochrome B from individual photobodies with distinct thermostabilities. Nat Commun 2020; 11:1660. [PMID: 32245953 PMCID: PMC7125078 DOI: 10.1038/s41467-020-15526-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 03/10/2020] [Indexed: 12/30/2022] Open
Abstract
Warm temperature is postulated to induce plant thermomorphogenesis through a signaling mechanism similar to shade, as both destabilize the active form of the photoreceptor and thermosensor phytochrome B (phyB). At the cellular level, shade antagonizes phyB signaling by triggering phyB disassembly from photobodies. Here we report temperature-dependent photobody localization of fluorescent protein-tagged phyB (phyB-FP) in the epidermal cells of Arabidopsis hypocotyl and cotyledon. Our results demonstrate that warm temperature elicits different photobody dynamics than those by shade. Increases in temperature from 12 °C to 27 °C incrementally reduce photobody number by stimulating phyB-FP disassembly from selective thermo-unstable photobodies. The thermostability of photobodies relies on phyB's photosensory module. Surprisingly, elevated temperatures inflict opposite effects on phyB's functions in the hypocotyl and cotyledon despite inducing similar photobody dynamics, indicative of tissue/organ-specific temperature signaling circuitry either downstream of photobody dynamics or independent of phyB. Our results thus provide direct cell biology evidence supporting an early temperature signaling mechanism via dynamic assembly/disassembly of individual photobodies possessing distinct thermostabilities.
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Affiliation(s)
- Joseph Hahm
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Keunhwa Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Yongjian Qiu
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA.
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Cheng MC, Enderle B, Kathare PK, Islam R, Hiltbrunner A, Huq E. PCH1 and PCHL Directly Interact with PIF1, Promote Its Degradation, and Inhibit Its Transcriptional Function during Photomorphogenesis. MOLECULAR PLANT 2020; 13:499-514. [PMID: 32061894 PMCID: PMC7167218 DOI: 10.1016/j.molp.2020.02.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 12/18/2019] [Accepted: 02/07/2020] [Indexed: 05/17/2023]
Abstract
PHOTOPERIODIC CONTROL OF HYPOCOTYL 1 (PCH1) and PCH1-LIKE (PCHL) were shown to directly bind to phytochrome B (phyB) and suppress phyB thermal reversion, resulting in plants with dramatically enhanced light sensitivity. Here, we show that PCH1 and PCHL also positively regulate various light responses, including seed germination, hypocotyl gravitropism, and chlorophyll biosynthesis, by physically interacting with PHYTOCHROME INTERACTING FACTOR 1 (PIF1) and CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1). PCH1 and PCHL interact with PIF1 both in the dark and light, and regulate PIF1 abundance. Moreover, PCH1 and PCHL facilitate the physical interaction between phyB and PIF1 in vivo to promote the light-induced degradation of PIF1. PCH1 and PCHL also inhibit the DNA-binding ability of PIF1 to negatively regulate the expressions of PIF1 target genes. In addition, PCH1 and PCHL interact with COP1 and undergo degradation through the 26S proteasome pathway in the dark. Consistently, pch1 suppresses cop1 phenotype in darkness. Collectively, our study reveals a novel mechanism by which PCH1 and PCHL regulate diverse light responses not only by stabilizing phyB Pfr form but also by directly interacting with PIF1 and COP1, providing a molecular understanding of the control of hypocotyl growth by these proteins.
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Affiliation(s)
- Mei-Chun Cheng
- Molecular Biosciences, University of Texas at Austin, NHB 2.616, Stop A5000, 100 East 24th Street, Austin, TX 78712-1095, USA
| | - Beatrix Enderle
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Praveen Kumar Kathare
- Molecular Biosciences, University of Texas at Austin, NHB 2.616, Stop A5000, 100 East 24th Street, Austin, TX 78712-1095, USA
| | - Rafya Islam
- Molecular Biosciences, University of Texas at Austin, NHB 2.616, Stop A5000, 100 East 24th Street, Austin, TX 78712-1095, USA
| | - Andreas Hiltbrunner
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Enamul Huq
- Molecular Biosciences, University of Texas at Austin, NHB 2.616, Stop A5000, 100 East 24th Street, Austin, TX 78712-1095, USA.
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39
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Sanchez SE, Rugnone ML, Kay SA. Light Perception: A Matter of Time. MOLECULAR PLANT 2020; 13:363-385. [PMID: 32068156 PMCID: PMC7056494 DOI: 10.1016/j.molp.2020.02.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 02/10/2020] [Accepted: 02/12/2020] [Indexed: 05/02/2023]
Abstract
Optimizing the perception of external cues and regulating physiology accordingly help plants to cope with the constantly changing environmental conditions to which they are exposed. An array of photoreceptors and intricate signaling pathways allow plants to convey the surrounding light information and synchronize an endogenous timekeeping system known as the circadian clock. This biological clock integrates multiple cues to modulate a myriad of downstream responses, timing them to occur at the best moment of the day and the year. Notably, the mechanism underlying entrainment of the light-mediated clock is not clear. This review addresses known interactions between the light-signaling and circadian-clock networks, focusing on the role of light in clock entrainment and known molecular players in this process.
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Affiliation(s)
- Sabrina E Sanchez
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Matias L Rugnone
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Steve A Kay
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
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40
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Klose C, Nagy F, Schäfer E. Thermal Reversion of Plant Phytochromes. MOLECULAR PLANT 2020; 13:386-397. [PMID: 31812690 DOI: 10.1016/j.molp.2019.12.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/21/2019] [Accepted: 12/03/2019] [Indexed: 05/18/2023]
Abstract
Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development. Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion, also termed dark reversion. Although the term "dark reversion" is justified by historical reasons and frequently used in the literature, "thermal reversion" more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the review. Thermal reversion is a critical parameter for the light sensitivity of phytochrome-mediated responses and has been studied for decades, often resulting in contradictory findings. Thermal reversion is an intrinsic property of the phytochrome molecules but can be modulated by intra- and intermolecular interactions, as well as biochemical modifications, such as phosphorylation. In this review, we outline the research history of phytochrome thermal reversion, highlighting important predictions that have been made before knowing the molecular basis. We further summarize and discuss recent findings about the molecular mechanisms regulating phytochrome thermal reversion and its functional roles in light and temperature sensing in plants.
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Affiliation(s)
- Cornelia Klose
- Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany.
| | - Ferenc Nagy
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62, 6726 Szeged, Hungary
| | - Eberhard Schäfer
- Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany
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41
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Piya S, Liu J, Burch-Smith T, Baum TJ, Hewezi T. A role for Arabidopsis growth-regulating factors 1 and 3 in growth-stress antagonism. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1402-1417. [PMID: 31701146 PMCID: PMC7031083 DOI: 10.1093/jxb/erz502] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 11/05/2019] [Indexed: 05/21/2023]
Abstract
Growth-regulating factors (GRFs) belong to a small family of transcription factors that are highly conserved in plants. GRFs regulate many developmental processes and plant responses to biotic and abiotic stimuli. Despite the importance of GRFs, a detailed mechanistic understanding of their regulatory functions is still lacking. In this study, we used ChIP sequencing (ChIP-seq) to identify genome-wide binding sites of Arabidopsis GRF1 and GRF3, and correspondingly their direct downstream target genes. RNA-sequencing (RNA-seq) analysis revealed that GRF1 and GRF3 regulate the expression of a significant number of the identified direct targets. The target genes unveiled broad regulatory functions of GRF1 and GRF3 in plant growth and development, phytohormone biosynthesis and signaling, and the cell cycle. Our analyses also revealed that clock core genes and genes with stress- and defense-related functions are most predominant among the GRF1- and GRF3-bound targets, providing insights into a possible role for these transcription factors in mediating growth-defense antagonism and integrating environmental stimuli into developmental programs. Additionally, GRF1 and GRF3 target molecular nodes of growth-defense antagonism and modulate the levels of defense- and development-related hormones in opposite directions. Taken together, our results point to GRF1 and GRF3 as potential key determinants of plant fitness under stress conditions.
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Affiliation(s)
- Sarbottam Piya
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA
| | - Jinyi Liu
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA
- Present address: College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Tessa Burch-Smith
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Thomas J Baum
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, USA
| | - Tarek Hewezi
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA
- Correspondence:
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42
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Viczián A, Ádám É, Staudt AM, Lambert D, Klement E, Romero Montepaone S, Hiltbrunner A, Casal J, Schäfer E, Nagy F, Klose C. Differential phosphorylation of the N-terminal extension regulates phytochrome B signaling. THE NEW PHYTOLOGIST 2020; 225:1635-1650. [PMID: 31596952 DOI: 10.1111/nph.16243] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/24/2019] [Indexed: 05/04/2023]
Abstract
Phytochrome B (phyB) is an excellent light quality and quantity sensor that can detect subtle changes in the light environment. The relative amounts of the biologically active photoreceptor (phyB Pfr) are determined by the light conditions and light independent thermal relaxation of Pfr into the inactive phyB Pr, termed thermal reversion. Little is known about the regulation of thermal reversion and how it affects plants' light sensitivity. In this study we identified several serine/threonine residues on the N-terminal extension (NTE) of Arabidopsis thaliana phyB that are differentially phosphorylated in response to light and temperature, and examined transgenic plants expressing nonphosphorylatable and phosphomimic phyB mutants. The NTE of phyB is essential for thermal stability of the Pfr form, and phosphorylation of S86 particularly enhances the thermal reversion rate of the phyB Pfr-Pr heterodimer in vivo. We demonstrate that S86 phosphorylation is especially critical for phyB signaling compared with phosphorylation of the more N-terminal residues. Interestingly, S86 phosphorylation is reduced in light, paralleled by a progressive Pfr stabilization under prolonged irradiation. By investigating other phytochromes (phyD and phyE) we provide evidence that acceleration of thermal reversion by phosphorylation represents a general mechanism for attenuating phytochrome signaling.
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Affiliation(s)
- András Viczián
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Éva Ádám
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62, H-6726, Szeged, Hungary
- Research Institute of Translational Biomedicine, Department of Dermatology and Allergology, University of Szeged, H-6726, Szeged, Hungary
| | - Anne-Marie Staudt
- Institute of Biology II, University of Freiburg, 79104, Freiburg, Germany
| | - Dorothee Lambert
- Institute of Biology II, University of Freiburg, 79104, Freiburg, Germany
| | - Eva Klement
- Laboratory of Proteomics Research, Biological Research Centre, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Sofia Romero Montepaone
- Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Universidad de Buenos Aires and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1417DSE, Buenos Aires, Argentina
| | - Andreas Hiltbrunner
- Institute of Biology II, University of Freiburg, 79104, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104, Freiburg, Germany
| | - Jorge Casal
- Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía, Universidad de Buenos Aires and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1417DSE, Buenos Aires, Argentina
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, CONICET, C1405BWE, Buenos Aires, Argentina
| | - Eberhard Schäfer
- Institute of Biology II, University of Freiburg, 79104, Freiburg, Germany
| | - Ferenc Nagy
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Cornelia Klose
- Institute of Biology II, University of Freiburg, 79104, Freiburg, Germany
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43
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A Proposed Methodology to Analyze Plant Growth and Movement from Phenomics Data. REMOTE SENSING 2019. [DOI: 10.3390/rs11232839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Image analysis of developmental processes in plants reveals both growth and organ movement. This study proposes a methodology to study growth and movement. It includes the standard acquisition of internal and external reference points and coordinates, coordinates transformation, curve fitting and the corresponding statistical analysis. Several species with different growth habits were used including Antirrhinum majus, A. linkianum, Petunia x hybrida and Fragaria x ananassa. Complex growth patterns, including gated growth, could be identified using a generalized additive model. Movement, and in some cases, growth, could not be adjusted to curves due to drastic changes in position. The area under the curve was useful in order to identify the initial stage of growth of an organ, and its growth rate. Organs displayed either continuous movements during the day with gated day/night periods of maxima, or sharp changes in position coinciding with day/night shifts. The movement was dependent on light in petunia and independent in F. ananassa. Petunia showed organ movement in both growing and fully-grown organs, while A. majus and F. ananassa showed both leaf and flower movement patterns linked to growth. The results indicate that different mathematical fits may help quantify growth rate, growth duration and gating. While organ movement may complicate image and data analysis, it may be a surrogate method to determine organ growth potential.
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BBX4, a phyB-interacting and modulated regulator, directly interacts with PIF3 to fine tune red light-mediated photomorphogenesis. Proc Natl Acad Sci U S A 2019; 116:26049-26056. [PMID: 31776262 DOI: 10.1073/pnas.1915149116] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phytochrome B (phyB) absorbs red light signals and subsequently initiates a set of molecular events in plant cells to promote photomorphogenesis. Here we show that phyB directly interacts with B-BOX CONTAINING PROTEIN 4 (BBX4), a positive regulator of red light signaling, and positively controls its abundance in red light. BBX4 associates with PHYTOCHROME INTERACTING FACTOR 3 (PIF3) and represses PIF3 transcriptional activation activity and PIF3-controlled gene expression. The degradation of BBX4 in darkness is dependent on CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) and the 26S proteasome system. Collectively, BBX4 acts as a key component of the phyB-PIF3-mediated signaling module and fine tunes the red light action. phyB promotes the accumulation of BBX4, which in turn serves to repress PIF3 action through direct physical interaction to promote photomorphogenic development in red light.
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45
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Molecular mechanisms underlying phytochrome-controlled morphogenesis in plants. Nat Commun 2019; 10:5219. [PMID: 31745087 PMCID: PMC6864062 DOI: 10.1038/s41467-019-13045-0] [Citation(s) in RCA: 226] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 10/17/2019] [Indexed: 11/08/2022] Open
Abstract
Phytochromes are bilin-binding photosensory receptors which control development over a broad range of environmental conditions and throughout the whole plant life cycle. Light-induced conformational changes enable phytochromes to interact with signaling partners, in particular transcription factors or proteins that regulate them, resulting in large-scale transcriptional reprograming. Phytochromes also regulate promoter usage, mRNA splicing and translation through less defined routes. In this review we summarize our current understanding of plant phytochrome signaling, emphasizing recent work performed in Arabidopsis. We compare and contrast phytochrome responses and signaling mechanisms among land plants and highlight open questions in phytochrome research.
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46
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He T, Hill CB, Angessa TT, Zhang XQ, Chen K, Moody D, Telfer P, Westcott S, Li C. Gene-set association and epistatic analyses reveal complex gene interaction networks affecting flowering time in a worldwide barley collection. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:5603-5616. [PMID: 31504706 PMCID: PMC6812734 DOI: 10.1093/jxb/erz332] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 08/13/2019] [Indexed: 05/10/2023]
Abstract
Single-marker genome-wide association studies (GWAS) have successfully detected associations between single nucleotide polymorphisms (SNPs) and agronomic traits such as flowering time and grain yield in barley. However, the analysis of individual SNPs can only account for a small proportion of genetic variation, and can only provide limited knowledge on gene network interactions. Gene-based GWAS approaches provide enormous opportunity both to combine genetic information and to examine interactions among genetic variants. Here, we revisited a previously published phenotypic and genotypic data set of 895 barley varieties grown in two years at four different field locations in Australia. We employed statistical models to examine gene-phenotype associations, as well as two-way epistasis analyses to increase the capability to find novel genes that have significant roles in controlling flowering time in barley. Genetic associations were tested between flowering time and corresponding genotypes of 174 putative flowering time-related genes. Gene-phenotype association analysis detected 113 genes associated with flowering time in barley, demonstrating the unprecedented power of gene-based analysis. Subsequent two-way epistasis analysis revealed 19 pairs of gene×gene interactions involved in controlling flowering time. Our study demonstrates that gene-based association approaches can provide higher capacity for future crop improvement to increase crop performance and adaptation to different environments.
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Affiliation(s)
- Tianhua He
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Camilla Beate Hill
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Tefera Tolera Angessa
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Xiao-Qi Zhang
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Kefei Chen
- SAGI-WEST, Faculty of Science and Engineering, Curtin University, Bentley, WA, Australia
| | | | - Paul Telfer
- Australian Grain Technologies Pty Ltd (AGT), SA, Australia
| | - Sharon Westcott
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Chengdao Li
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Hubei Jingzhou, China
- Correspondence:
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47
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Ronald J, Davis SJ. Focusing on the nuclear and subnuclear dynamics of light and circadian signalling. PLANT, CELL & ENVIRONMENT 2019; 42:2871-2884. [PMID: 31369151 DOI: 10.1111/pce.13634] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/27/2019] [Accepted: 07/30/2019] [Indexed: 05/22/2023]
Abstract
Circadian clocks provide organisms the ability to synchronize their internal physiological responses with the external environment. This process, termed entrainment, occurs through the perception of internal and external stimuli. As with other organisms, in plants, the perception of light is a critical for the entrainment and sustainment of circadian rhythms. Red, blue, far-red, and UV-B light are perceived by the oscillator through the activity of photoreceptors. Four classes of photoreceptors signal to the oscillator: phytochromes, cryptochromes, UVR8, and LOV-KELCH domain proteins. In most cases, these photoreceptors localize to the nucleus in response to light and can associate to subnuclear structures to initiate downstream signalling. In this review, we will highlight the recent advances made in understanding the mechanisms facilitating the nuclear and subnuclear localization of photoreceptors and the role these subnuclear bodies have in photoreceptor signalling, including to the oscillator. We will also highlight recent progress that has been made in understanding the regulation of the nuclear and subnuclear localization of components of the plant circadian clock.
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Affiliation(s)
- James Ronald
- Department of Biology, University of York, YO10 5DD, York, UK
| | - Seth J Davis
- Department of Biology, University of York, YO10 5DD, York, UK
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48
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Lama S, Broda M, Abbas Z, Vaneechoutte D, Belt K, Säll T, Vandepoele K, Van Aken O. Neofunctionalization of Mitochondrial Proteins and Incorporation into Signaling Networks in Plants. Mol Biol Evol 2019; 36:974-989. [PMID: 30938771 PMCID: PMC6501883 DOI: 10.1093/molbev/msz031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Because of their symbiotic origin, many mitochondrial proteins are well conserved across eukaryotic kingdoms. It is however less obvious how specific lineages have obtained novel nuclear-encoded mitochondrial proteins. Here, we report a case of mitochondrial neofunctionalization in plants. Phylogenetic analysis of genes containing the Domain of Unknown Function 295 (DUF295) revealed that the domain likely originated in Angiosperms. The C-terminal DUF295 domain is usually accompanied by an N-terminal F-box domain, involved in ubiquitin ligation via binding with ASK1/SKP1-type proteins. Due to gene duplication, the gene family has expanded rapidly, with 94 DUF295-related genes in Arabidopsis thaliana alone. Two DUF295 family subgroups have uniquely evolved and quickly expanded within Brassicaceae. One of these subgroups has completely lost the F-box, but instead obtained strongly predicted mitochondrial targeting peptides. We show that several representatives of this DUF295 Organellar group are effectively targeted to plant mitochondria and chloroplasts. Furthermore, many DUF295 Organellar genes are induced by mitochondrial dysfunction, whereas F-Box DUF295 genes are not. In agreement, several Brassicaceae-specific DUF295 Organellar genes were incorporated in the evolutionary much older ANAC017-dependent mitochondrial retrograde signaling pathway. Finally, a representative set of DUF295 T-DNA insertion mutants was created. No obvious aberrant phenotypes during normal growth and mitochondrial dysfunction were observed, most likely due to the large extent of gene duplication and redundancy. Overall, this study provides insight into how novel mitochondrial proteins can be created via “intercompartmental” gene duplication events. Moreover, our analysis shows that these newly evolved genes can then be specifically integrated into relevant, pre-existing coexpression networks.
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Affiliation(s)
- Sbatie Lama
- Department of Biology, Lund University, Lund, Sweden
| | - Martyna Broda
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Australia
| | - Zahra Abbas
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Australia
| | - Dries Vaneechoutte
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.,VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Katharina Belt
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Australia.,CSIRO, Floreat, WA, Australia
| | - Torbjörn Säll
- Department of Biology, Lund University, Lund, Sweden
| | - Klaas Vandepoele
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.,VIB Center for Plant Systems Biology, Ghent, Belgium
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PCH1 regulates light, temperature, and circadian signaling as a structural component of phytochrome B-photobodies in Arabidopsis. Proc Natl Acad Sci U S A 2019; 116:8603-8608. [PMID: 30948632 DOI: 10.1073/pnas.1818217116] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The members of the phytochrome (phy) family of bilin-containing photoreceptors are major regulators of plant photomorphogenesis through their unique ability to photointerconvert between a biologically inactive red light-absorbing Pr state and an active far-red light-absorbing Pfr state. While the initial steps in Pfr signaling are unclear, an early event for the phyB isoform after photoconversion is its redistribution from the cytoplasm into subnuclear foci known as photobodies (PBs), which dissipate after Pfr reverts back to Pr by far-red irradiation or by temperature-dependent nonphotochemical reversion. Here we present evidence that PHOTOPERIODIC CONTROL OF HYPOCOTYL 1 (PCH1) functions both as an essential structural component of phyB-containing PBs and as a direct regulator of thermal reversion that is sufficient to stabilize phyB as Pfr in vitro. By examining the genetic interaction between a constitutively active phyBY276H-YFP allele (YHB-YFP) and PCH1, we show that the loss of PCH1 prevents YHB from coalescing into PBs without affecting its nuclear localization, whereas overexpression of PCH1 dramatically increases PB levels. Loss of PCH1, presumably by impacting phyB-PB assembly, compromises a number of events elicited in YHB-YFP plants, including their constitutive photomorphogenic phenotype, red light-regulated thermomorphogenesis, and input of phyB into the circadian clock. Conversely, elevated levels of both phyB and PCH1 generate stable, yet far-red light-reversible PBs that persisted for days. Collectively, our data demonstrate that the assembly of PCH1-containing PBs is critical for phyB signaling to multiple outputs and suggest that altering PB dynamics could be exploited to modulate plant responses to light and temperature.
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50
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Qiu Y, Li M, Kim RJA, Moore CM, Chen M. Daytime temperature is sensed by phytochrome B in Arabidopsis through a transcriptional activator HEMERA. Nat Commun 2019; 10:140. [PMID: 30635559 PMCID: PMC6329817 DOI: 10.1038/s41467-018-08059-z] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 12/14/2018] [Indexed: 11/13/2022] Open
Abstract
Ambient temperature sensing by phytochrome B (PHYB) in Arabidopsis is thought to operate mainly at night. Here we show that PHYB plays an equally critical role in temperature sensing during the daytime. In daytime thermosensing, PHYB signals primarily through the temperature-responsive transcriptional regulator PIF4, which requires the transcriptional activator HEMERA (HMR). HMR does not regulate PIF4 transcription, instead, it interacts directly with PIF4, to activate the thermoresponsive growth-relevant genes and promote warm-temperature-dependent PIF4 accumulation. A missense allele hmr-22, which carries a loss-of-function D516N mutation in HMR’s transcriptional activation domain, fails to induce the thermoresponsive genes and PIF4 accumulation. Both defects of hmr-22 could be rescued by expressing a HMR22 mutant protein fused with the transcriptional activation domain of VP16, suggesting a causal relationship between HMR-mediated activation of PIF4 target-genes and PIF4 accumulation. Together, this study reveals a daytime PHYB-mediated thermosensing mechanism, in which HMR acts as a necessary activator for PIF4-dependent induction of temperature-responsive genes and PIF4 accumulation. The phyB photoreceptor senses nighttime temperature in Arabidopsis plants cultivated in short-day photoperiods. Here the authors show that phyB can also promote thermomorphogenesis during constant light or the daytime, and acts via a HEMERA-dependent mechanism that promotes the activity and accumulation of PIF4.
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Affiliation(s)
- Yongjian Qiu
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Meina Li
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA.,School of Life Sciences, Guangzhou University, Guangzhou, 510006, China
| | - Ruth Jean-Ae Kim
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Carisha M Moore
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA.
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