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Jia X, Song M, Wang S, Liu T, Wang L, Guo L, Su L, Shi Y, Zheng X, Yang J. Arabidopsis phytochromes A and B synergistically repress SPA1 under blue light. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:888-894. [PMID: 36394421 DOI: 10.1111/jipb.13412] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/16/2022] [Indexed: 06/16/2023]
Abstract
In Arabidopsis, although studies have demonstrated that phytochrome A (phyA) and phyB are involved in blue light signaling, how blue light-activated phytochromes modulate the activity of the CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)-SUPPRESSOR OF PHYA-105 (SPA1) E3 complex remains largely unknown. Here, we show that phyA responds to early and weak blue light, whereas phyB responds to sustainable and strong blue light. Activation of both phyA and phyB by blue light inhibits SPA1 activity. Specifically, blue light irradiation promoted the nuclear import of both phytochromes to stimulate their binding to SPA1, abolishing SPA1's interaction with LONG HYPOCOTYL 5 (HY5) to release HY5, which promoted seedling photomorphogenesis.
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Affiliation(s)
- Xiaolin Jia
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
| | - Meifang Song
- Institute of Radiation Technology, Beijing Academy of Science and Technology, Beijing, 100875, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Shaoci Wang
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
| | - Tong Liu
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
| | - Lijian Wang
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
- Henan Police College, Zhengzhou, 450046, China
| | - Lin Guo
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Liang Su
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Beijing Genseed Technology Co., Ltd., Beijing, 100080, China
| | - Yong Shi
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
| | - Xu Zheng
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
| | - Jianping Yang
- State Key Laboratory of Wheat and Maize Crop Science, and Center for Crop Genome Engineering, Longzi Lake Campus, College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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Liu Q, Li Z, Zhang M, Dong S, Yang P, Zhang J, Loades E. Systematic analysis of photo/sko-regulated germination and post-germination development of shallow photodormant seeds in Nicotiana tabacum L. FRONTIERS IN PLANT SCIENCE 2023; 13:1042981. [PMID: 36714753 PMCID: PMC9875545 DOI: 10.3389/fpls.2022.1042981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 11/22/2022] [Indexed: 06/18/2023]
Abstract
INTRODUCTION Light is a major environmental factor in regulating germination and post-germination development of shallow photo-dormant seeds in Nicotiana tabacum L. (tobacco). However, its molecular mechanism remains largely unclear. METHODS AND RESULTS In this study, we compared the phenotypes of the seeds germinated under light and dark, and systematically investigated their regulatory networks by integrating transcriptomic and proteomic data. Under light, the germination increased ~25%, the length of the hypocotyl shortened ~3 cm, and the apical hook disappeared. 9, 161, 342 differentially expressed genes (DEGs) and 128, 185, 81 differentially expressed proteins (DEPs) were regulated by light in the development stage of seed imbibition, radicle protrusion and cotyledon expansion respectively. 0, 19 and 1 co-up-regulated and 1, 30 and 64 co-down-regulated DEGs (DEP) were observed in the three stages, respectively. Of them, 2S albumin large chain, was down-regulated by light in imbibed seed. Oleosin 18.5 kDa (OLEO1) and Glyceraldehyde-3-phosphate dehydrogenase (GAPA1), Oxygen-evolving enhancer protein 1-1 and anchloroplastic (PSBO1), hub genes (proteins) in protein-protein interaction network (PPI), were downregulated and up-regulated in germinated seeds by light, respectively. OLEO1, a hub gene (proteins), was down-regulated by light in post-germination seedling. CONCLUSION These results systematically revealed the molecular networks regulated by light during germination and post-germination development of shallow photo-dormant tobacco seeds.
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Affiliation(s)
- Qiyuan Liu
- College of Agriculture, University of Guizhou, Guiyang, Guizhou, China
| | - Zhenhua Li
- College of Agriculture, University of Guizhou, Guiyang, Guizhou, China
| | - Min Zhang
- College of Agriculture, University of Guizhou, Guiyang, Guizhou, China
| | - Shuai Dong
- College of Agriculture, University of Guizhou, Guiyang, Guizhou, China
| | - Pingping Yang
- College of Agriculture, University of Guizhou, Guiyang, Guizhou, China
| | - Jie Zhang
- China National Tobacco Corporation (CNTC) Key Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang, Guizhou, China
| | - Eddison Loades
- Department of Biological Sciences, Royal Holloway, University of London, London, United Kingdom
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Phytochrome A in plants comprises two structurally and functionally distinct populations — water-soluble phyA′ and amphiphilic phyA″. Biophys Rev 2022; 14:905-921. [DOI: 10.1007/s12551-022-00974-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 06/14/2022] [Indexed: 10/17/2022] Open
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Sineshchekov VA, Koppel LA, Bolle C. Two native types of phytochrome A, phyAʹ and phyAʺ, differ by the state of phosphorylation at the N-terminus as revealed by fluorescence investigations of the Ser/Ala mutant of rice phyA expressed in transgenic Arabidopsis. FUNCTIONAL PLANT BIOLOGY 2018; 45:150. [DOI: https:/doi.org/10.1071/fp16261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Phytochrome A (phyA) mediates different photoresponses what may be connected with the existence of its two types, phyAʹ and phyAʹʹ, differing by spectroscopic, photochemical and functional properties. We investigated a role of phyA phosphorylation in their formation turning to transgenic Arabidopsis thaliana (L. Heynh.) phyA or phyAphyB mutants overexpressing rice wild-type phyA (phyA WT) or mutant phyA (phyA SA) with the first 10 serines substituted by alanines. This prevents phyA phosphorylation at these sites and modifies photoresponses. Etiolated seedlings were employed and phyA parameters were evaluated with the use of low temperature fluorescence spectroscopy and photochemistry. Germination of seeds was induced by white light (WL) pre-treatment for 15 min or 3 h. Emission spectra of rice phyA WT and phyA SA were similar and their total content was comparable. However, the phyAʹ/phyAʹʹ proportion in phyA WT was high and varied with the duration of the WL pre-treatment, whereas in phyA SA it was substantially shifted towards phyAʹʹ and did not depend on the pre-illumination. This suggests that phyA SA comprises primarily or exclusively the phyAʹʹ pool and supports the notion that the two phyA types differ by the state of serine phosphorylation. phyAʹʹ was also found to be much more effective in the germination induction than phyAʹ.
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Sineshchekov VA, Koppel LA, Bolle C. Two native types of phytochrome A, phyA' and phyA", differ by the state of phosphorylation at the N-terminus as revealed by fluorescence investigations of the Ser/Ala mutant of rice phyA expressed in transgenic Arabidopsis. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:150-159. [PMID: 32291029 DOI: 10.1071/fp16261] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 11/01/2016] [Indexed: 06/11/2023]
Abstract
Phytochrome A (phyA) mediates different photoresponses what may be connected with the existence of its two types, phyA' and phyA'', differing by spectroscopic, photochemical and functional properties. We investigated a role of phyA phosphorylation in their formation turning to transgenic Arabidopsis thaliana (L. Heynh.) phyA or phyAphyB mutants overexpressing rice wild-type phyA (phyA WT) or mutant phyA (phyA SA) with the first 10 serines substituted by alanines. This prevents phyA phosphorylation at these sites and modifies photoresponses. Etiolated seedlings were employed and phyA parameters were evaluated with the use of low temperature fluorescence spectroscopy and photochemistry. Germination of seeds was induced by white light (WL) pre-treatment for 15min or 3h. Emission spectra of rice phyA WT and phyA SA were similar and their total content was comparable. However, the phyA'/phyA'' proportion in phyA WT was high and varied with the duration of the WL pre-treatment, whereas in phyA SA it was substantially shifted towards phyA'' and did not depend on the pre-illumination. This suggests that phyA SA comprises primarily or exclusively the phyA'' pool and supports the notion that the two phyA types differ by the state of serine phosphorylation. phyA'' was also found to be much more effective in the germination induction than phyA'.
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Affiliation(s)
| | - Larissa A Koppel
- Biology Department, MV Lomonosov Moscow State University, Moscow 119234, Russia
| | - Cordelia Bolle
- Biology Department, Ludwig Maximilian University, München, D-82152 Planegg-Martinsried, Germany
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Sheerin DJ, Hiltbrunner A. Molecular mechanisms and ecological function of far-red light signalling. PLANT, CELL & ENVIRONMENT 2017; 40:2509-2529. [PMID: 28102581 DOI: 10.1111/pce.12915] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 01/11/2017] [Accepted: 01/13/2017] [Indexed: 05/18/2023]
Abstract
Land plants possess the ability to sense and respond to far-red light (700-760 nm), which serves as an important environmental cue. Due to the nature of far-red light, it is not absorbed by chlorophyll and thus is enriched in canopy shade and will also penetrate deeper into soil than other visible wavelengths. Far-red light responses include regulation of seed germination, suppression of hypocotyl growth, induction of flowering and accumulation of anthocyanins, which depend on one member of the phytochrome photoreceptor family, phytochrome A (phyA). Here, we review the current understanding of the underlying molecular mechanisms of how plants sense far-red light through phyA and the physiological responses to this light quality. Light-activated phytochromes act on two primary pathways within the nucleus; suppression of the E3 ubiquitin ligase complex CUL4/DDB1COP1/SPA and inactivation of the PHYTOCHROME INTERACTING FACTOR (PIF) family of bHLH transcription factors. These pathways integrate with other signal transduction pathways, including phytohormones, for tissue and developmental stage specific responses. Unlike other phytochromes that mediate red-light responses, phyA is transported from the cytoplasm to the nucleus in far-red light by the shuttle proteins FAR-RED ELONGATED HYPOCOTYL 1 (FHY1) and FHY1-LIKE (FHL). However, additional mechanisms must exist that shift the action of phyA to far-red light; current hypotheses are discussed.
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Affiliation(s)
- David J Sheerin
- Institute of Biology II, Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
| | - Andreas Hiltbrunner
- Institute of Biology II, Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany
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7
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Viczián A, Klose C, Ádám É, Nagy F. New insights of red light-induced development. PLANT, CELL & ENVIRONMENT 2017; 40:2457-2468. [PMID: 27943362 DOI: 10.1111/pce.12880] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/04/2016] [Accepted: 12/05/2016] [Indexed: 05/14/2023]
Abstract
The red/far-red light absorbing photoreceptors phytochromes regulate development and growth and thus play an essential role in optimizing adaptation of the sessile plants to the ever-changing environment. Our understanding of how absorption of a red/far-red photon by phytochromes initiates/modifies diverse physiological responses has been steadily improving. Research performed in the last 5 years has been especially productive and led to significant conceptual changes about the mode of action of these photoreceptors. In this review, we focus on the phytochrome B photoreceptor, the major phytochrome species active in light-grown plants. We discuss how its light-independent inactivation (termed dark/thermal reversion), post-translational modification, including ubiquitination, phosphorylation and sumoylation, as well as heterodimerization with other phytochrome species modify red light-controlled physiological responses. Finally, we discuss how photobiological properties of phytochrome B enable this photoreceptor to function also as a thermosensor.
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Affiliation(s)
- András Viczián
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Cornelia Klose
- Institute of Biology2/Botany, University of Freiburg, Schänzlestrasse 1, D-79104, Freiburg, Germany
| | - Éva Ádám
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Ferenc Nagy
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
- Institute of Molecular Plant Science, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JH, UK
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Malik N, Agarwal P, Tyagi A. Emerging functions of multi-protein complex Mediator with special emphasis on plants. Crit Rev Biochem Mol Biol 2017; 52:475-502. [DOI: 10.1080/10409238.2017.1325830] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Naveen Malik
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Pinky Agarwal
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Akhilesh Tyagi
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
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9
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Su L, Hou P, Song M, Zheng X, Guo L, Xiao Y, Yan L, Li W, Yang J. Synergistic and Antagonistic Action of Phytochrome (Phy) A and PhyB during Seedling De-Etiolation in Arabidopsis thaliana. Int J Mol Sci 2015; 16:12199-212. [PMID: 26030677 PMCID: PMC4490439 DOI: 10.3390/ijms160612199] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/13/2015] [Accepted: 05/15/2015] [Indexed: 11/16/2022] Open
Abstract
It has been reported that Arabidopsis phytochrome (phy) A and phyB are crucial photoreceptors that display synergistic and antagonistic action during seedling de-etiolation in multiple light signaling pathways. However, the functional relationship between phyA and phyB is not fully understood under different kinds of light and in response to different intensities of such light. In this work, we compared hypocotyl elongation of the phyA-211 phyB-9 double mutant with the wild type, the phyA-211 and phyB-9 single mutants under different intensities of far-red (FR), red (R), blue (B) and white (W) light. We confirmed that phyA and phyB synergistically promote seedling de-etiolation in B-, B plus R-, W- and high R-light conditions. The correlation of endogenous ELONGATED HYPOCOTYL 5 (HY5) protein levels with the trend of hypocotyl elongation of all lines indicate that both phyA and phyB promote seedling photomorphogenesis in a synergistic manner in high-irradiance white light. Gene expression analyses of RBCS members and HY5 suggest that phyB and phyA act antagonistically on seedling development under FR light.
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Affiliation(s)
- Liang Su
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Pei Hou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Meifang Song
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
- Beijing Radiation Center, Beijing 100875, China.
| | - Xu Zheng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Lin Guo
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Yang Xiao
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Lei Yan
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Wanchen Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
| | - Jianping Yang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Su L, Hou P, Song M, Zheng X, Guo L, Xiao Y, Yan L, Li W, Yang J. Synergistic and Antagonistic Action of Phytochrome (Phy) A and PhyB during Seedling De-Etiolation in Arabidopsis thaliana. Int J Mol Sci 2015. [PMID: 26030677 DOI: 10.3390/2fijms160612199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
It has been reported that Arabidopsis phytochrome (phy) A and phyB are crucial photoreceptors that display synergistic and antagonistic action during seedling de-etiolation in multiple light signaling pathways. However, the functional relationship between phyA and phyB is not fully understood under different kinds of light and in response to different intensities of such light. In this work, we compared hypocotyl elongation of the phyA-211 phyB-9 double mutant with the wild type, the phyA-211 and phyB-9 single mutants under different intensities of far-red (FR), red (R), blue (B) and white (W) light. We confirmed that phyA and phyB synergistically promote seedling de-etiolation in B-, B plus R-, W- and high R-light conditions. The correlation of endogenous ELONGATED HYPOCOTYL 5 (HY5) protein levels with the trend of hypocotyl elongation of all lines indicate that both phyA and phyB promote seedling photomorphogenesis in a synergistic manner in high-irradiance white light. Gene expression analyses of RBCS members and HY5 suggest that phyB and phyA act antagonistically on seedling development under FR light.
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Affiliation(s)
- Liang Su
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Pei Hou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Meifang Song
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
- Beijing Radiation Center, Beijing 100875, China.
| | - Xu Zheng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Lin Guo
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Yang Xiao
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Lei Yan
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Wanchen Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
| | - Jianping Yang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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11
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Song MF, Zhang S, Hou P, Shang HZ, Gu HK, Li JJ, Xiao Y, Guo L, Su L, Gao JW, Yang JP. Ectopic expression of a phytochrome B gene from Chinese cabbage (Brassica rapa L. ssp. pekinensis) in Arabidopsis thaliana promotes seedling de-etiolation, dwarfing in mature plants, and delayed flowering. PLANT MOLECULAR BIOLOGY 2015; 87:633-43. [PMID: 25724426 DOI: 10.1007/s11103-015-0302-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/18/2015] [Indexed: 05/22/2023]
Abstract
Phytochrome B (phyB) is an essential red light receptor that predominantly mediates seedling de-etiolation, shade-avoidance response, and flowering time. In this study, we isolate a full-length cDNA of PHYB, designated BrPHYB, from Chinese cabbage (Brassica rapa L. ssp. pekinensis), and we find that BrphyB protein has high amino acid sequence similarity and the closest evolutionary relationship to Arabidopsis thaliana phyB (i.e., AtphyB). Quantitative reverse transcription (RT)-PCR results indicate that the BrPHYB gene is ubiquitously expressed in different tissues under all light conditions. Constitutive expression of the BrPHYB gene in A. thaliana significantly enhances seedling de-etiolation under red- and white-light conditions, and causes dwarf stature in mature plants. Unexpectedly, overexpression of BrPHYB in transgenic A. thaliana resulted in reduced expression of gibberellins biosynthesis genes and delayed flowering under short-day conditions, whereas AtPHYB overexpression caused enhanced expression of FLOWERING LOCUS T and earlier flowering. Our results suggest that BrphyB might play an important role in regulating the development of Chinese cabbage. BrphyB and AtphyB have conserved functions during de-etiolation and vegetative plant growth and divergent functions in the regulation of flowering time.
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Affiliation(s)
- Mei-Fang Song
- Beijing Radiation Center, Beijing, 100875, People's Republic of China
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12
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Lu XD, Zhou CM, Xu PB, Luo Q, Lian HL, Yang HQ. Red-light-dependent interaction of phyB with SPA1 promotes COP1-SPA1 dissociation and photomorphogenic development in Arabidopsis. MOLECULAR PLANT 2015; 8:467-78. [PMID: 25744387 DOI: 10.1016/j.molp.2014.11.025] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/13/2014] [Accepted: 11/14/2014] [Indexed: 05/18/2023]
Abstract
Arabidopsis phytochromes (phyA-phyE) are photoreceptors dedicated to sensing red/far-red light. Phytochromes promote photomorphogenic developments upon light irradiation via a signaling pathway that involves rapid degradation of PIFs (PHYTOCHROME INTERACTING FACTORS) and suppression of COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1) nuclear accumulation, through physical interactions with PIFs and COP1, respectively. Both phyA and phyB, the two best characterized phytochromes, regulate plant photomorphogenesis predominantly under far-red light and red light, respectively. It has been demonstrated that SPA1 (SUPPRESSOR OF PHYTOCHROME A 1) associates with COP1 to promote COP1 activity and suppress photomorphogenesis. Here, we report that the mechanism underlying phyB-promoted photomorphogenesis in red light involves direct physical and functional interactions between red-light-activated phyB and SPA1. We found that SPA1 acts genetically downstream of PHYB to repress photomorphogenesis in red light. Protein interaction studies in both yeast and Arabidopsis demonstrated that the photoactivated phyB represses the association of SPA1 with COP1, which is mediated, at least in part, through red-light-dependent interaction of phyB with SPA1. Moreover, we show that phyA physically interacts with SPA1 in a Pfr-form-dependent manner, and that SPA1 acts downstream of PHYA to regulate photomorphogenesis in far-red light. This study provides a genetic and biochemical model of how photoactivated phyB represses the activity of COP1-SPA1 complex through direct interaction with SPA1 to promote photomorphogenesis in red light.
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Affiliation(s)
- Xue-Dan Lu
- Key Laboratory of Urban Agriculture (South) Ministry of Agriculture and School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Chuan-Miao Zhou
- National Key Laboratory of Plant Molecular Genetics (NKLPMG), Institute of Plant Physiology and Ecology (SIPPE), Shanghai Institutes for Biological Sciences (SIBS), Shanghai 200032, China
| | - Peng-Bo Xu
- School of Life Sciences and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Qian Luo
- Key Laboratory of Urban Agriculture (South) Ministry of Agriculture and School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Hong-Li Lian
- Key Laboratory of Urban Agriculture (South) Ministry of Agriculture and School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
| | - Hong-Quan Yang
- School of Life Sciences and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, China.
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Martínez-García JF, Gallemí M, Molina-Contreras MJ, Llorente B, Bevilaqua MRR, Quail PH. The shade avoidance syndrome in Arabidopsis: the antagonistic role of phytochrome a and B differentiates vegetation proximity and canopy shade. PLoS One 2014; 9:e109275. [PMID: 25333270 PMCID: PMC4204825 DOI: 10.1371/journal.pone.0109275] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 09/02/2014] [Indexed: 11/18/2022] Open
Abstract
Light limitation caused by dense vegetation is one of the greatest threats to plant survival in natural environments. Plants detect such neighboring vegetation as a reduction in the red to far-red ratio (R:FR) of the incoming light. The low R:FR signal, perceived by phytochromes, initiates a set of responses collectively known as the shade avoidance syndrome, intended to reduce the degree of current or future shade from neighbors by overtopping such competitors or inducing flowering to ensure seed production. At the seedling stage these responses include increased hypocotyl elongation. We have systematically analyzed the Arabidopsis seedling response and the contribution of phyA and phyB to perception of decreased R:FR, at three different levels of photosynthetically active radiation. Our results show that the shade avoidance syndrome, induced by phyB deactivation, is gradually antagonized by phyA, operating through the so-called FR-High Irradiance Response, in response to high FR levels in a range that simulates plant canopy shade. The data indicate that the R:FR signal distinguishes between the presence of proximal, but non-shading, neighbors and direct foliar shade, via a intrafamily photosensory attenuation mechanism that acts to suppress excessive reversion toward skotomorphogenic development under prolonged direct vegetation shade.
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Affiliation(s)
- Jaime F. Martínez-García
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
- Centre for Research in Agricultural Genomics (CRAG), Consortium CSIC-IRTA-UAB-UB, Barcelona, Spain
- * E-mail:
| | - Marçal Gallemí
- Centre for Research in Agricultural Genomics (CRAG), Consortium CSIC-IRTA-UAB-UB, Barcelona, Spain
| | | | - Briardo Llorente
- Centre for Research in Agricultural Genomics (CRAG), Consortium CSIC-IRTA-UAB-UB, Barcelona, Spain
| | - Maycon R. R. Bevilaqua
- Centre for Research in Agricultural Genomics (CRAG), Consortium CSIC-IRTA-UAB-UB, Barcelona, Spain
- CAPES foundation, Ministry of Education of Brazil, Brasilia - DF, Brazil
| | - Peter H. Quail
- Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America
- US Department of Agriculture/Agriculture Research Service, Plant Gene Expression Center, Albany, California, United States of America
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Arana MV, Sánchez-Lamas M, Strasser B, Ibarra SE, Cerdán PD, Botto JF, Sánchez RA. Functional diversity of phytochrome family in the control of light and gibberellin-mediated germination in Arabidopsis. PLANT, CELL & ENVIRONMENT 2014; 37:2014-23. [PMID: 24471455 DOI: 10.1111/pce.12286] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 12/19/2013] [Accepted: 12/27/2013] [Indexed: 05/22/2023]
Abstract
In several species, seed germination is regulated by light in a way that restricts seedling emergence to the environmental conditions that are likely to be favourable for the success of the new individual, and therefore, this behaviour is recognized to have adaptive value. The phytochromes are one of the most relevant photoreceptors involved in light perception by plants. We explored the redundancy and diversity functions of the phytochrome family in the control of seed responsiveness to light and gibberellins (GA) by using a set of phytochrome mutants of Arabidopsis. Our data show that, in addition to the well-known role of phyB in the promotion of germination in response to high red to far-red ratios (R/FR), phyE and phyD stimulate germination at very low R/FR ratios, probably by promoting the action of phyA. Further, we show that phyC regulates negatively the seed responsiveness to light, unravelling unexpected functions for phyC in seed germination. Finally, we find that seed responsiveness to GA is mainly controlled by phyB, with phyC, phyD and phyE having relevant roles when acting in a phyB-deficient background. Our results indicate that phytochromes have multiple and complex roles during germination depending on the active photoreceptor background.
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Affiliation(s)
- M V Arana
- Instituto Nacional de Tecnología Agropecuaria, EEA Bariloche and CONICET, San Carlos de Bariloche, Río Negro, R8403DVZ, Argentina
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15
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Casal JJ, Candia AN, Sellaro R. Light perception and signalling by phytochrome A. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2835-45. [PMID: 24220656 DOI: 10.1093/jxb/ert379] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In etiolated seedlings, phytochrome A (phyA) mediates very-low-fluence responses (VLFRs), which initiate de-etiolation at the interphase between the soil and above-ground environments, and high-irradiance responses (HIR), which complete de-etiolation under dense canopies and require more sustained activation with far-red light. Light-activated phyA is transported to the nucleus by FAR-RED ELONGATED HYPOCOTYL1 (FHY1). The nuclear pool of active phyA increases under prolonged far-red light of relatively high fluence rates. This condition maximizes the rate of FHY1-phyA complex assembly and disassembly, allowing FHY1 to return to the cytoplasm to translocate further phyA to the nucleus, to replace phyA degraded in the proteasome. The core signalling pathways downstream of nuclear phyA involve the negative regulation of CONSTITUTIVE PHOTOMORPHOGENIC 1, which targets for degradation transcription factors required for photomorphogenesis, and PHYTOCHROME-INTERACTING FACTORs, which are transcription factors that repress photomorphogenesis. Under sustained far-red light activation, released FHY1 can also be recruited with active phyA to target gene promoters as a transcriptional activator, and nuclear phyA signalling activates a positive regulatory loop involving BELL-LIKE HOMEODOMAIN 1 that reinforces the HIR.
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Affiliation(s)
- J J Casal
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires and CONICET, 1417 Buenos Aires, Argentina Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-CONICET, C1405BWE Buenos Aires, Argentina
| | - A N Candia
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires and CONICET, 1417 Buenos Aires, Argentina
| | - R Sellaro
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires and CONICET, 1417 Buenos Aires, Argentina
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16
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Gibbs DC, Donohue K. Gene duplication and the environmental regulation of physiology and development. Ecol Evol 2014; 4:2202-16. [PMID: 25360261 PMCID: PMC4201434 DOI: 10.1002/ece3.1099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 04/07/2014] [Indexed: 11/08/2022] Open
Abstract
When different life stages have different environmental tolerances, development needs to be regulated so that each life stage experiences environmental conditions that are suitable for it, if fitness is to be maintained. Restricting the timing of developmental transitions to occur under specific combinations of environmental conditions is therefore adaptively important. However, impeding development can itself incur demographic and fitness costs. How do organisms regulate development and physiological processes so that they occur under the broadest range of permissive conditions? Gene duplication offers one solution: Multiple genes contribute to the same downstream process, but do so under distinct combinations of environmental conditions. We present a simple model to examine how environmental sensitivities of genes and how gene duplication influence the distribution of environmental conditions under which an end process will proceed. The model shows that the duplication of genes that retain their downstream function but diverge in environmental sensitivities can allow an end process to proceed under more than one distinct combination of environmental conditions. The outcomes depend on how upstream genes regulate downstream components, which genes in the pathway have diversified in their sensitivities, and the structure of the pathway.
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Affiliation(s)
- David C Gibbs
- Department of Biology, Duke University Box 90338, Durham, North Carolina, 27708
| | - Kathleen Donohue
- Department of Biology, Duke University Box 90338, Durham, North Carolina, 27708
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17
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Donohue K. WHY ONTOGENY MATTERS DURING ADAPTATION: DEVELOPMENTAL NICHE CONSTRUCTION AND PLEIOTORPY ACROSS THE LIFE CYCLE INARABIDOPSIS THALIANA. Evolution 2013; 68:32-47. [DOI: 10.1111/evo.12284] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 09/25/2013] [Indexed: 12/14/2022]
Affiliation(s)
- Kathleen Donohue
- Department of Biology; Duke University; Box 90338 Durham NC 27708
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18
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Torres-Galea P, Hirtreiter B, Bolle C. Two GRAS proteins, SCARECROW-LIKE21 and PHYTOCHROME A SIGNAL TRANSDUCTION1, function cooperatively in phytochrome A signal transduction. PLANT PHYSIOLOGY 2013; 161:291-304. [PMID: 23109688 PMCID: PMC3532260 DOI: 10.1104/pp.112.206607] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Photoreceptors, especially the far-red light-absorbing phytochrome A, play a crucial role in early seedling development, triggering the transition from etiolated to photomorphogenic growth. Here, we describe the biological functions of two GRAS proteins from Arabidopsis (Arabidopsis thaliana), SCARECROW-LIKE21 (SCL21) and PHYTOCHROME A SIGNAL TRANSDUCTION1 (PAT1), which are specifically involved in phytochrome A signal transduction. Loss-of-function mutants show an elongated hypocotyl under far-red light and are impaired in other far-red high-irradiance responses. The SCL21 transcript itself is down-regulated by far-red light in a phytochrome A- and PAT1-dependent manner. Our results demonstrate that both SCL21 and PAT1 are positive regulators of phytochrome A signal transduction for several high-irradiance responses. Genetic and biochemical evidence suggest a direct interaction of the two proteins.
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19
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Zheng X, Wu S, Zhai H, Zhou P, Song M, Su L, Xi Y, Li Z, Cai Y, Meng F, Yang L, Wang H, Yang J. Arabidopsis phytochrome B promotes SPA1 nuclear accumulation to repress photomorphogenesis under far-red light. THE PLANT CELL 2013; 25:115-33. [PMID: 23371951 PMCID: PMC3584529 DOI: 10.1105/tpc.112.107086] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Revised: 12/10/2012] [Accepted: 12/19/2012] [Indexed: 05/19/2023]
Abstract
Phytochrome A (phyA) is the primary photoreceptor mediating deetiolation under far-red (FR) light, whereas phyB predominantly regulates light responses in red light. SUPPRESSOR OF PHYA-105 (SPA1) forms an E3 ubiquitin ligase complex with CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1), which is responsible for the degradation of various photomorphogenesis-promoting factors, resulting in desensitization to light signaling. However, the role of phyB in FR light signaling and the regulatory pathway from light-activated phytochromes to the COP1-SPA1 complex are largely unknown. Here, we confirm that PHYB overexpression causes an etiolation response with reduced ELONGATED HYPOCOTYL5 (HY5) accumulation under FR light. Notably, phyB exerts its nuclear activities and promotes seedling etiolation in both the presence and absence of phyA in response to FR light. PhyB acts upstream of SPA1 and is functionally dependent on it in FR light signaling. PhyB interacts and forms a protein complex with SPA1, enhancing its nuclear accumulation under FR light. During the dark-to-FR transition, phyB is rapidly imported into the nucleus and facilitates nuclear SPA1 accumulation. These findings support the notion that phyB plays a role in repressing FR light signaling. Activity modulation of the COP1-SPA E3 complex by light-activated phytochromes is an effective and pivotal regulatory step in light signaling.
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Affiliation(s)
- Xu Zheng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Suowei Wu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Huqu Zhai
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Peng Zhou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Meifang Song
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Liang Su
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yulin Xi
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhiyong Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yingfan Cai
- College of Bio-information, Chongqing University of Posts and Telecommunication, Chongqing 400065, China
| | - Fanhua Meng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Li Yang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Haiyang Wang
- College of Life Sciences, Capital Normal University, Beijing 100048, China
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520
| | - Jianping Yang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Address correspondence to
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20
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Klose C, Büche C, Fernandez AP, Schäfer E, Zwick E, Kretsch T. The mediator complex subunit PFT1 interferes with COP1 and HY5 in the regulation of Arabidopsis light signaling. PLANT PHYSIOLOGY 2012; 160:289-307. [PMID: 22760208 PMCID: PMC3440207 DOI: 10.1104/pp.112.197319] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 07/02/2012] [Indexed: 05/19/2023]
Abstract
Arabidopsis (Arabidopsis thaliana) mutants hypersensitive to far-red light were isolated under a light program of alternating red and far-red light pulses and were named eid (for empfindlicher im dunkelroten Licht). The dominant eid3 mutant carries a missense mutation in a conserved domain of PHYTOCHROME AND FLOWERING TIME1 (PFT1), an important component of the plant mediator coactivator complex, which links promoter-bound transcriptional regulators to RNA polymerase II complexes. Epistatic analyses were performed to obtain information about the coaction between the mutated PFT1(eid3) and positively and negatively acting components of light signaling cascades. The data presented here provide clear evidence that the mutation mainly enhances light sensitivity downstream of phytochrome A (phyA) and modulates phyB function. Our results demonstrate that the Mediator component cooperates with CONSTITUTIVE PHOTORMORPHOGENIC1 in the regulation of light responses and that the hypersensitive phenotype strictly depends on the presence of the ELONGATED HYPOCOTYL5 transcription factor, an important positive regulator of light-dependent gene expression. Expression profile analyses revealed that PFT1(eid3) alters the transcript accumulation of light-regulated genes even in darkness. Our data further indicate that PFT1 regulates the floral transition downstream of phyA. The PFT1 missense mutation seems to create a constitutively active transcription factor by mimicking an early step in light signaling.
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21
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Warnasooriya SN, Porter KJ, Montgomery BL. Tissue- and isoform-specific phytochrome regulation of light-dependent anthocyanin accumulation in Arabidopsis thaliana. PLANT SIGNALING & BEHAVIOR 2011; 6:624-31. [PMID: 21455024 PMCID: PMC3172825 DOI: 10.4161/psb.6.5.15084] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 02/07/2011] [Accepted: 02/08/2011] [Indexed: 05/19/2023]
Abstract
Phytochromes regulate light- and sucrose-dependent anthocyanin synthesis and accumulation in many plants. Mesophyll-specific phyA alone has been linked to the regulation of anthocyanin accumulation in response to far-red light in Arabidopsis thaliana. However, multiple mesophyll-localized phytochromes were implicated in the photoregulation of anthocyanin accumulation in red-light conditions. Here, we report a role for mesophyll-specific phyA in blue-light-dependent regulation of anthocyanin levels and novel roles for individual phy isoforms in the regulation of anthocyanin accumulation under red illumination. These results provide new insight into spatial- and isoform-specific regulation of pigmentation by phytochromes in A. thaliana.
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Affiliation(s)
- Sankalpi N Warnasooriya
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
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22
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Kneissl J, Wachtler V, Chua NH, Bolle C. OWL1: an Arabidopsis J-domain protein involved in perception of very low light fluences. THE PLANT CELL 2009; 21:3212-25. [PMID: 19808946 PMCID: PMC2782286 DOI: 10.1105/tpc.109.066472] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 08/28/2009] [Accepted: 09/14/2009] [Indexed: 05/05/2023]
Abstract
To sense ambient light conditions in order to optimize their growth and development, plants employ a battery of photoreceptors responsive to light quality and quantity. Essential for the sensing of red and far-red (FR) light is the phytochrome family of photoreceptors. Among them, phytochrome A is special because it mediates responses to different light conditions, including both very low fluences (very low fluence response [VLFR]) and high irradiances (high irradiance response [HIR]). In contrast with the FR-HIR signaling pathway, in which several intermediates of the signaling pathway have been identified, specific components of the VLFR pathway remain unknown. Here, we describe owl1 (for orientation under very low fluences of light), a mutant that is specific for the VLFR, suggesting that VLFR and HIR pathways are genetically distinct, although some common mechanisms can be observed. OWL1 codes for a ubiquitous J-domain protein essential for germination, cotyledon opening, hypocotyl elongation, and deviation of the direction of hypocotyl growth from the vertical under very low light conditions. Additionally, we observed a flowering phenotype suggesting a role for the VLFR during the whole life cycle of a plant. OWL1 interacts with the basic helix-loop-helix HFR1 (LONG HYPOCOTYL IN FAR-RED) transcription factor, previously characterized as a component of the FR-HIR pathway. Both proteins are involved in the agravitropic response under FR light. We propose a central function of OWL1 in the VLFR pathway, which is essential for plant survival under unfavorable light conditions.
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Affiliation(s)
- Julia Kneissl
- Institute of Botany, Department for Biology I, Ludwig-Maximilians-Universität, 82152 Planegg-Martinsried, Germany
| | - Volker Wachtler
- Laboratory of Plant Molecular Biology, The Rockefeller University, New York 10021
| | - Nam-Hai Chua
- Laboratory of Plant Molecular Biology, The Rockefeller University, New York 10021
| | - Cordelia Bolle
- Institute of Botany, Department for Biology I, Ludwig-Maximilians-Universität, 82152 Planegg-Martinsried, Germany
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23
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Dechaine JM, Gardner G, Weinig C. Phytochromes differentially regulate seed germination responses to light quality and temperature cues during seed maturation. PLANT, CELL & ENVIRONMENT 2009; 32:1297-309. [PMID: 19453482 DOI: 10.1111/j.1365-3040.2009.01998.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The ratio of red to far-red light (R : FR) experienced by seeds during maturation affects germination, but the genetic regulation of this effect is poorly understood. In Arabidopsis thaliana, responses to R : FR are governed by five phytochrome photoreceptors, PHYA-PHYE. PHYA, PHYB and PHYE mediate germination, but their roles in germination response to the seed maturation environment are largely unknown. Seeds of A. thaliana phytochrome mutants and natural accessions were matured in a factorial combination of cold (16 degrees C) and warm (24 degrees C) temperatures and high (R : FR = 1) and low (R : FR = 0.6) R : FR environments, resembling sunlight and foliar shade, respectively. Germination was observed in resulting seeds. All five phytochromes mediated germination responses to seed maturation temperature and/or R : FR environment. PHYA suppressed germination in seeds matured under cold temperature, and PHYB promoted germination under the same conditions. PHYD and PHYE promoted germination of seeds matured under warm temperature, but this effect diminished when seeds matured under reduced R : FR. The A. thaliana natural accessions exhibited interesting variation in germination responses to the experimental conditions. Our results suggest that the role of individual PHY loci in regulating plant responses to R : FR varies depending on temperature and provide novel insights into the genetic basis of maternal effects.
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Affiliation(s)
- Jennifer M Dechaine
- Department of Plant Biology, University of Minnesota, St Paul, MN 55108, USA.
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24
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Donohue K, Heschel MS, Butler CM, Barua D, Sharrock RA, Whitelam GC, Chiang GCK. Diversification of phytochrome contributions to germination as a function of seed-maturation environment. THE NEW PHYTOLOGIST 2008; 177:367-379. [PMID: 18028293 DOI: 10.1111/j.1469-8137.2007.02281.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Environmental conditions during seed maturation influence germination, but the genetic basis of maternal environmental effects on germination is virtually unknown. Using single and multiple mutants of phytochromes, it is shown here that different phytochromes contributed to germination differently, depending on seed-maturation conditions. Arabidopsis thaliana wild-type seeds that were matured under cool temperatures were intensely dormant compared with seeds matured at warmer temperature, and this dormancy was broken only after warm seed-stratification followed by cold seed-stratification. The warm-cold stratification broke dormancy in fresh seeds but not in dry after-ripened seeds. Functional PHYB and PHYD were necessary to break cool-induced dormancy, which indicates a previously unknown and ecologically important function for PHYD. Disruption of PHYA in combination with PHYD (but not PHYB) restored germination to near wild-type levels, indicating that PHYA contributes to the maintenance of cool-induced dormancy on a phyD background. Effects of seed-maturation temperature were much stronger than effects of seed-maturation photoperiod. PHYB contributed to germination somewhat more strongly in seeds matured under short days, whereas PHYD contributed to germination somewhat more strongly in seeds matured under long days. The variable contributions of different phytochromes to germination as a function of seed-maturation conditions reveal further functional diversification of the phytochromes during the process of germination. This study identifies among the first genes to be associated with maternal environmental effects on germination.
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Affiliation(s)
- Kathleen Donohue
- Department of Organismic and Evolutionary Biology, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA
| | - M Shane Heschel
- Department of Organismic and Evolutionary Biology, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA
| | - Colleen M Butler
- Department of Organismic and Evolutionary Biology, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA
| | - Deepak Barua
- Department of Organismic and Evolutionary Biology, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA
| | - Robert A Sharrock
- Department of Plant Sciences and Plant Pathology, Montana State University, PO Box 173150, Bozeman, MT 59717-3150, USA
| | - Garry C Whitelam
- Institute of Genetics, Adrian Building, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - George C K Chiang
- Department of Organismic and Evolutionary Biology, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA
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25
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Kneissl J, Shinomura T, Furuya M, Bolle C. A rice phytochrome A in Arabidopsis: The Role of the N-terminus under red and far-red light. MOLECULAR PLANT 2008; 1:84-102. [PMID: 20031917 DOI: 10.1093/mp/ssm010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The phytochrome (phy)A and phyB photoreceptors mediate three photobiological response modes in plants; whereas phyA can mediate the very-low-fluence response (VLFR), the high-irradiance response (HIR) and, to some extent, the low fluence response (LFR), phyB and other type II phytochromes only mediate the LFR. To investigate to what level a rice phyA can complement for Arabidopsis phyA or phyB function and to evaluate the role of the serine residues in the first 20 amino acids of the N-terminus of phyA, we examined VLFR, LFR, and HIR responses in phyB and phyAphyB mutant plants transformed with rice PHYA cDNA or a mutant rice PHYA cDNA in which the first 10 serine residues were mutated to alanines (phyA SA). Utilizing mutants without endogenous phyB allowed the evaluation of red-light-derived responses sensed by the rice phyA. In summary, the WT rice phyA could complement VLFR and LFR responses such as inhibition of hypocotyl elongation under pulses of FR or continuous R light, induction of flowering and leaf expansion, whereas the phyA SA was more specific for HIR responses (e.g. inhibition of hypocotyl elongation and anthocyanin accumulation under continuous far-red light). As the N-terminal serines can no longer be phosphorylated in the phyA SA mutant, this suggests a role for phosphorylation discriminating between the different phyA-dependent responses. The efficacy of the rice phyA expressed in Arabidopsis was dependent upon the developmental age of the plants analyzed and on the physiological response, suggesting a stage-dependent downstream modulation of phytochrome signaling.
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Affiliation(s)
- Julia Kneissl
- Ludwig-Maximilians-Universität München, Bereich Botanik, Menzinger Str. 67, 80638 München, Germany
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26
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Torres-Galea P, Huang LF, Chua NH, Bolle C. The GRAS protein SCL13 is a positive regulator of phytochrome-dependent red light signaling, but can also modulate phytochrome A responses. Mol Genet Genomics 2006; 276:13-30. [PMID: 16680434 DOI: 10.1007/s00438-006-0123-y] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 03/25/2006] [Indexed: 01/27/2023]
Abstract
Phytochrome photoreceptors enable plants to perceive divergent light signals leading to adaptive changes in response to differing environmental conditions. However, the mechanism of light signal transduction is not fully understood. Here we report the identification of a new signaling intermediate from Arabidopsis thaliana, Scarecrow-like (SCL)13, which serves as a positive regulator of continuous red light signals downstream of phytochrome B (phyB). SCL13 antisense lines exhibit reduced sensitivity towards red light, but only a distinct subset of phyB-mediated responses is affected, indicating that SCL13 executes its major role in hypocotyl elongation during de-etiolation. Genetic evidence suggests that SCL13 is also needed to modulate phytochrome A (phyA) signal transduction in a phyB-independent way. The SCL13 protein is localized in the cytoplasm, but can also be detected in the nucleus. Overexpression of both a nuclear and cytoplasmic localized SCL13 protein leads to a hypersensitive phenotype under red light indicating that SCL13 is biologically active in both compartments. SCL13 is a member of the plant-specific GRAS protein family, which is involved in various different developmental and signaling pathways. A previously identified phytochrome A signaling intermediate, PAT1, belongs to the same subbranch of GRAS proteins as SCL13. Although both proteins are involved in phytochrome signaling, each is specific for a different light condition and regulates a different subset of responses.
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Affiliation(s)
- Patricia Torres-Galea
- Department für Biologie I/Bereich Botanik, Ludwig-Maximilians-University, Menzinger Str. 67, 80638, Munich, Germany
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27
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Appenroth KJ, Lenk G, Goldau L, Sharma R. Tomato seed germination: regulation of different response modes by phytochrome B2 and phytochrome A. PLANT, CELL & ENVIRONMENT 2006; 29:701-9. [PMID: 17080619 DOI: 10.1111/j.1365-3040.2005.01455.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Lycopersicon esculentum seeds germinate after rehydration in complete darkness. This response was inhibited by a far-red light (FR) pulse, and the inhibition was reversed by a red light (R) pulse. Comparison of germination in phytochrome-deficient mutants (phyA, phyB1, phyB2, phyAB1, phyB1B2 and phyAB1B2) showed that phytochrome B2 (PhyB2) mediates both responses. The germination was inhibited by strong continuous R (38 micromol m(-2) s(-1)), whereas weak R (28 nmol m(-2) s(-1)) stimulated seed germination. Hourly applied R pulses of the same photon fluence partially replaced the effect of strong continuous R. This response was called 'antagonistic' because it counteracts the low fluence response (LFR) induced by a single R pulse. This antagonistic response might be an adaptation to a situation where the seeds sit on the soil surface in full sunlight (adverse for germination), while weak R might reflect that situation under a layer of soil. Unexpectedly, the effects of continuous R or repeated R pulses were mediated by phytochrome A (PhyA). We therefore suggest that low levels of PhyA in its FR-absorbing form (Pfr) cause inhibition of seed germination produced either by extended R irradiation (by degradation of PhyA-Pfr) or by extended FR irradiation [keeping a low Pfr/R-absorbing form (Pr) ratio].
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Affiliation(s)
- Klaus J Appenroth
- University of Jena, Institute of General Botany and Plant Physiology, Dornburger Str. 159, 07743 Jena, Germany.
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28
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Chen M, Ni M. RED AND FAR-RED INSENSITIVE 2, a RING-domain zinc finger protein, mediates phytochrome-controlled seedling deetiolation responses. PLANT PHYSIOLOGY 2006; 140:457-65. [PMID: 16384903 PMCID: PMC1361316 DOI: 10.1104/pp.105.073163] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 11/19/2005] [Accepted: 11/29/2005] [Indexed: 05/04/2023]
Abstract
Light is arguably the most important resource for plants, and an array of photosensory pigments enables plants to develop optimally in a broad range of ambient-light conditions. The red- and far-red-light-absorbing photosensory pigments or phytochromes (phy) regulate seedling deetiolation responses, photoperiodic flowering, and circadian rhythm. We have identified a long hypocotyl mutant under red and far-red light, rfi2-1 (red and far-red insensitive 2 to 1). rfi2-1 was also impaired in phytochrome-mediated end-of-day far-red light response, cotyledon expansion, far-red light block of greening, and light-induced expression of CHLOROPHYLL A/B BINDING PROTEIN 3 and CHALCONE SYNTHASE. Introduction of rfi2-1 mutation into phyB-9 or phyA-211 did not enhance or suppress the long hypocotyl phenotype of phyB-9 or phyA-211 under red or far-red light, respectively, and RFI2 likely functions downstream of phyB or phyA. RFI2 was identified through the segregation of two T-DNA insertions into different recombinant lines, genetic rescue, and phenotypic characterization of a second mutant allele rfi2-2. RFI2 encodes a protein with a C3H2C3-type zinc finger or RING domain known to mediate protein-protein or protein-DNA interactions, and RFI2 is localized to the nucleus. RFI2 therefore reveals a signaling step that mediates phytochrome control of seedling deetiolation.
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Affiliation(s)
- Mingjie Chen
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108, USA
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Mazzella MA, Arana MV, Staneloni RJ, Perelman S, Rodriguez Batiller MJ, Muschietti J, Cerdán PD, Chen K, Sánchez RA, Zhu T, Chory J, Casal JJ. Phytochrome control of the Arabidopsis transcriptome anticipates seedling exposure to light. THE PLANT CELL 2005; 17:2507-16. [PMID: 16024587 PMCID: PMC1197430 DOI: 10.1105/tpc.105.034322] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Phytochromes mediate a profound developmental shift when dark-grown seedlings are exposed to light. Here, we show that a subset of genes is upregulated in phytochrome B (phyB) mutants even before dark-grown Arabidopsis thaliana seedlings are exposed to light. Most of these genes bear the RY cis motif, which is a binding site of the transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3), and the phyB mutation also enhances ABI3 expression. These changes in transcriptome have physiological consequences, because seedlings of the abi3 mutant showed enhanced responses to pulses of far-red light, whereas ABI3 overexpressers exhibited the opposite pattern. Seedlings of the wild type derived from seeds germinated in full darkness showed enhanced expression of genes bearing the RY cis motif and reduced responses to far-red light. We propose that, via changes in ABI3 expression, light, perceived mainly by phyB in the seed, generates a downstream transdevelopmental phase signal that preconditions the seedling to its most likely environment.
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Affiliation(s)
- María Agustina Mazzella
- Instituto de Investigaciones en Ingenieria Genetica y Biologia Molecular, 1428 Buenos Aires, Argentina
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Oh E, Kim J, Park E, Kim JI, Kang C, Choi G. PIL5, a phytochrome-interacting basic helix-loop-helix protein, is a key negative regulator of seed germination in Arabidopsis thaliana. THE PLANT CELL 2004; 16:3045-58. [PMID: 15486102 PMCID: PMC527197 DOI: 10.1105/tpc.104.025163] [Citation(s) in RCA: 316] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Accepted: 09/02/2004] [Indexed: 05/18/2023]
Abstract
The first decision made by an angiosperm seed, whether to germinate or not, is based on integration of various environmental signals such as water and light. The phytochromes (Phys) act as red and far-red light (Pfr) photoreceptors to mediate light signaling through yet uncharacterized pathways. We report here that the PIF3-like 5 (PIL5) protein, a basic helix-loop-helix transcription factor, is a key negative regulator of phytochrome-mediated seed germination. PIL5 preferentially interacts with the Pfr forms of Phytochrome A (PhyA) and Phytochrome B (PhyB). Analyses of a pil5 mutant in conjunction with phyA and phyB mutants, a pif3 pil5 double mutant, and PIL5 overexpression lines indicate that PIL5 is a negative factor in Phy-mediated promotion of seed germination, inhibition of hypocotyl negative gravitropism, and inhibition of hypocotyl elongation. Our data identify PIL5 as the first Phy-interacting protein that regulates seed germination.
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Affiliation(s)
- Eunkyoo Oh
- Department of Biological Sciences, KAIST, Daejeon 305-701, Korea
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Markelz NH, Costich DE, Brutnell TP. Photomorphogenic responses in maize seedling development. PLANT PHYSIOLOGY 2003; 133:1578-91. [PMID: 14645729 PMCID: PMC300715 DOI: 10.1104/pp.103.029694] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Revised: 08/11/2003] [Accepted: 09/15/2003] [Indexed: 05/19/2023]
Abstract
As an emerging maize (Zea mays) seedling senses light, there is a decrease in the rate of mesocotyl elongation, an induction of root growth, and an expansion of leaves. In leaf tissues, mesophyll and bundle sheath cell fate is determined, and the proplastids of each differentiate into the dimorphic chloroplasts typical of each cell type. Although it has been inferred from recent studies in several model plant species that multiple photoreceptor systems mediate this process, surprisingly little is known of light signal transduction in maize. Here, we examine two photomorphogenic responses in maize: inhibition of mesocotyl elongation and C4 photosynthetic differentiation. Through an extensive survey of white, red, far-red, and blue light responses among a diverse collection of germplasm, including a phytochrome-deficient mutant elm1, we show that light response is a highly variable trait in maize. Although all inbreds examined appear to have a functional phytochrome signal transduction pathway, several lines showed reduced sensitivity to blue light. A significant correlation was observed between light response and subpopulation, suggesting that light responsiveness may be a target of artificial selection. An examination of C4 gene expression patterns under various light regimes in the standard W22 inbred and elm1 indicate that cell-specific patterns of C4 gene expression are maintained in fully differentiated tissues independent of light quality. To our knowledge, these findings represent the first comprehensive survey of light response in maize and are discussed in relation to maize breeding strategies.
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Affiliation(s)
- Nicole H Markelz
- Boyce Thompson Institute, Cornell University, Tower Road, Ithaca, New York 14853, USA
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Cerdán PD, Chory J. Regulation of flowering time by light quality. Nature 2003; 423:881-5. [PMID: 12815435 DOI: 10.1038/nature01636] [Citation(s) in RCA: 293] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2002] [Accepted: 04/14/2003] [Indexed: 11/09/2022]
Abstract
The transition to flowering in plants is regulated by environmental factors such as temperature and light. Plants grown under dense canopies or at high density perceive a decrease in the ratio of red to far-red incoming light. This change in light quality serves as a warning of competition, triggering a series of responses known collectively as the 'shade-avoidance syndrome'. During shade avoidance, stems elongate at the expense of leaf expansion, and flowering is accelerated. Of the five phytochromes-a family of red/far-red light photoreceptors-in Arabidopsis, phytochrome B (phyB) has the most significant role in shade-avoidance responses, but the mechanisms by which phyB regulates flowering in response to altered ratios of red to far-red light are largely unknown. Here we identify PFT1 (PHYTOCHROME AND FLOWERING TIME 1), a nuclear protein that acts in a phyB pathway and induces flowering in response to suboptimal light conditions. PFT1 functions downstream of phyB to regulate the expression of FLOWERING LOCUS T (FT), providing evidence for the existence of a light-quality pathway that regulates flowering time in plants.
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Affiliation(s)
- Pablo D Cerdán
- Howard Hughes Medical Institute and Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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Halliday KJ, Whitelam GC. Changes in photoperiod or temperature alter the functional relationships between phytochromes and reveal roles for phyD and phyE. PLANT PHYSIOLOGY 2003; 131:1913-20. [PMID: 12692350 PMCID: PMC166947 DOI: 10.1104/pp.102.018135] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2002] [Revised: 01/02/2003] [Accepted: 01/02/2003] [Indexed: 05/18/2023]
Abstract
The phytochromes are one of the means via which plants obtain information about their immediate environment and the changing seasons. Phytochromes have important roles in developmental events such as the switch to flowering, the timing of which can be crucial for the reproductive success of the plant. Analysis of phyB mutants has revealed that phyB plays a major role in this process. We have recently shown, however, that the flowering phenotype of the phyB monogenic mutant is temperature dependent. A modest reduction in temperature to 16 degrees C was sufficient to abolish the phyB mutant early-flowering phenotype present at 22 degrees C. Using mutants null for one or more phytochrome species, we have now shown that phyA, phyD, and phyE, play greater roles with respect to phyB in the control of flowering under cooler conditions. This change in the relative contributions of individual phytochromes appears to be important for maintaining control of flowering in response to modest alterations in ambient temperature. We demonstrate that changes in ambient temperature or photoperiod can alter the hierarchy and/or the functional relationships between phytochrome species. These experiments reveal new roles for phyD and phyE and provide valuable insights into how the phytochromes help to maintain development in the natural environment.
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Affiliation(s)
- Karen J Halliday
- School of Biological Sciences, University of Bristol, United Kingdom.
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Affiliation(s)
- Jennifer Nemhauser
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037-1099
- Corresponding author: Plant Biology Laboratory, Salk Institute, 10010 North Torrey Pines Road, La Jolla, California 92037-1099; Phone 858-453-4100 x1128; Fax 858-558-6379;
| | - Joanne Chory
- Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037-1099
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, California 92037-1099
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Hennig L, Stoddart WM, Dieterle M, Whitelam GC, Schäfer E. Phytochrome E controls light-induced germination of Arabidopsis. PLANT PHYSIOLOGY 2002; 128:194-200. [PMID: 11788765 DOI: 10.1104/pp.010559] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Germination of Arabidopsis seeds is light dependent and under phytochrome control. Previously, phytochromes A and B and at least one additional, unspecified phytochrome were shown to be involved in this process. Here, we used a set of photoreceptor mutants to test whether phytochrome D and/or phytochrome E can control germination of Arabidopsis. The results show that only phytochromes B and E, but not phytochrome D, participate directly in red/far-red light (FR)-reversible germination. Unlike phytochromes B and D, phytochrome E did not inhibit phytochrome A-mediated germination. Surprisingly, phytochrome E was required for germination of Arabidopsis seeds in continuous FR. However, inhibition of hypocotyl elongation by FR, induction of cotyledon unfolding, and induction of agravitropic growth were not affected by loss of phytochrome E. Therefore, phytochrome E is not required per se for phytochrome A-mediated very low fluence responses and the high irradiance response. Immunoblotting revealed that the need of phytochrome E for germination in FR was not caused by altered phytochrome A levels. These results uncover a novel role of phytochrome E in plant development and demonstrate the considerable functional diversification of the closely related phytochromes B, D, and E.
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Affiliation(s)
- Lars Hennig
- Department of Biology, Leicester University, Leicester LE1 7RH, United Kingdom
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Nagy F, Schäfer E. Phytochromes control photomorphogenesis by differentially regulated, interacting signaling pathways in higher plants. ANNUAL REVIEW OF PLANT BIOLOGY 2002; 53:329-355. [PMID: 12221979 DOI: 10.1146/annurev.arplant.53.100301.135302] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this review the kinetic properties of both phytochrome A and B measured by in vivo spectroscopy in Arabidopsis are described. Inactivation of phyA is mediated by destruction and that of phyB by fast dark reversion. Recent observations, describing a complex interaction network of various phytochromes and cryptochromes, are also discussed. The review describes recent analysis of light-dependent nuclear translocation of phytochromes and genetic and molecular dissection of phyA- and phyB-mediated signal transduction. After nuclear transport, both phyA- and phyB-mediated signal transduction probably include the formation of light-dependent transcriptional complexes. Although this hypothesis is quite attractive and probably true for some responses, it cannot account for the complex network of phyA-mediated signaling and the interaction with the circadian clock. In addition, the biological function of phytochromes localized in the cytosol remains to be elucidated.
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Affiliation(s)
- Ferenc Nagy
- Institute of Plant Biology, Biological Research Center, H-6701 Szeged, Hungary.
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