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Lemke MD, Abate AN, Woodson JD. Investigating the mechanism of chloroplast singlet oxygen signaling in the Arabidopsis thaliana accelerated cell death 2 mutant. PLANT SIGNALING & BEHAVIOR 2024; 19:2347783. [PMID: 38699898 PMCID: PMC11073415 DOI: 10.1080/15592324.2024.2347783] [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: 01/29/2024] [Accepted: 04/19/2024] [Indexed: 05/05/2024]
Abstract
As sessile organisms, plants have evolved complex signaling mechanisms to sense stress and acclimate. This includes the use of reactive oxygen species (ROS) generated during dysfunctional photosynthesis to initiate signaling. One such ROS, singlet oxygen (1O2), can trigger retrograde signaling, chloroplast degradation, and programmed cell death. However, the signaling mechanisms are largely unknown. Several proteins (e.g. PUB4, OXI1, EX1) are proposed to play signaling roles across three Arabidopsis thaliana mutants that conditionally accumulate chloroplast 1O2 (fluorescent in blue light (flu), chlorina 1 (ch1), and plastid ferrochelatase 2 (fc2)). We previously demonstrated that these mutants reveal at least two chloroplast 1O2 signaling pathways (represented by flu and fc2/ch1). Here, we test if the 1O2-accumulating lesion mimic mutant, accelerated cell death 2 (acd2), also utilizes these pathways. The pub4-6 allele delayed lesion formation in acd2 and restored photosynthetic efficiency and biomass. Conversely, an oxi1 mutation had no measurable effect on these phenotypes. acd2 mutants were not sensitive to excess light (EL) stress, yet pub4-6 and oxi1 both conferred EL tolerance within the acd2 background, suggesting that EL-induced 1O2 signaling pathways are independent from spontaneous lesion formation. Thus, 1O2 signaling in acd2 may represent a third (partially overlapping) pathway to control cellular degradation.
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Affiliation(s)
- Matthew D. Lemke
- The School of Plant Sciences, University of Arizona, Tucson, AZ, USA
| | - Alexa N. Abate
- The School of Plant Sciences, University of Arizona, Tucson, AZ, USA
| | - Jesse D. Woodson
- The School of Plant Sciences, University of Arizona, Tucson, AZ, USA
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2
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Rai S, Lemke MD, Arias AM, Mendez MFG, Dehesh K, Woodson JD. Plant U-Box 4 regulates chloroplast stress signaling and programmed cell death via Salicylic acid modulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.13.593788. [PMID: 38798329 PMCID: PMC11118471 DOI: 10.1101/2024.05.13.593788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
In response to environmental stress, chloroplasts generate reactive oxygen species, including singlet oxygen (1O2), which regulates nuclear gene expression (retrograde signaling), chloroplast turnover, and programmed cell death (PCD). Yet, the central signaling mechanisms and downstream responses remain poorly understood. The Arabidopsis thaliana plastid ferrochelatase two (fc2) mutant conditionally accumulates 1O2 and involves Plant U-Box 4 (PUB4), a cytoplasmic E3 ubiquitin ligase, in propagating these signals. To gain insights into 1O2 signaling pathways, we compared transcriptomes of fc2 and fc2 pub4 mutants. The accumulation of 1O2 in fc2 plants broadly repressed genes involved in chloroplast function and photosynthesis, while 1O2 induced genes and transcription factors involved in abiotic and biotic stress, the biosynthesis of jasmonic acid (JA), and Salicylic acid (SA). Elevated JA and SA levels were observed in stressed fc2 plants, but were not responsible for PCD. pub4 reversed the majority of 1O2-induced gene expression in fc2 and reduced the JA content, but maintained elevated levels of SA even in the absence of 1O2 stress. Reducing SA levels in fc2 pub4 restored 1O2 signaling and light sensitivity. Together, this work demonstrates that SA plays a protective role during photo-oxidative stress and that PUB4 mediates 1O2 signaling by modulating its levels.
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Affiliation(s)
- Snigdha Rai
- The School of Plant Sciences, University of Arizona, Tucson, AZ
| | | | - Anika M. Arias
- The School of Plant Sciences, University of Arizona, Tucson, AZ
| | - Maria F. Gomez Mendez
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA
| | - Katayoon Dehesh
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA
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3
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Herbst J, Pang X, Roling L, Grimm B. A novel tetratricopeptide-repeat protein, TTP1, forms complexes with glutamyl-tRNA reductase and protochlorophyllide oxidoreductase during tetrapyrrole biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2027-2045. [PMID: 38070484 DOI: 10.1093/jxb/erad491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 12/08/2023] [Indexed: 03/28/2024]
Abstract
The biosynthesis of the tetrapyrrole end-products chlorophyll and heme depends on a multifaceted control mechanism that acts primarily at the post-translational level upon the rate-limiting step of 5-aminolevulinic acid synthesis and upon light-dependent protochlorophyllide oxidoreductase (POR). These regulatory processes require auxiliary factors that modulate the activity, stability, complex formation, and subplastidal localization of the relevant proteins. Together, they ensure optimal metabolic flow during the day and at night. As an Arabidopsis homolog of the POR-interacting tetratricopeptide-repeat protein (Pitt) first reported in Synechocystis, we characterize tetrapyrrole biosynthesis-regulating tetratricopeptide-repeat protein1 (TTP1). TTP1 is a plastid-localized, membrane-bound factor that interacts with POR, the Mg protoporphyrin monomethylester cyclase CHL27, glutamyl-tRNA reductase (GluTR), GluTR-binding protein, and FLUORESCENCE IN BLUE LIGHT. Lack of TTP1 leads to accumulation of GluTR, enhanced 5-aminolevulinic acid synthesis and lower levels of POR. Knockout mutants show enhanced sensitivity to reactive oxygen species and a slower greening of etiolated seedlings. Based on our studies, the interaction of TTP1 with GluTR and POR does not directly inhibit their enzymatic activity and contribute to the control of 5-aminolevulinic acid synthesis. Instead, we propose that TTP1 sequesters a fraction of these proteins on the thylakoid membrane, and contributes to their stability.
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Affiliation(s)
- Josephine Herbst
- Humboldt-Universität zu Berlin, Institute of Biology-Plant Physiology, Philippstr. 13, Building 12, 10099 Berlin, Germany
- VIB-U Gent Center for Plant Systems Biology, Ghent University, Technologiepark-Zwijnaarde 71, 9052 Ghent, Belgium
| | - Xiaoqing Pang
- Humboldt-Universität zu Berlin, Institute of Biology-Plant Physiology, Philippstr. 13, Building 12, 10099 Berlin, Germany
| | - Lena Roling
- Humboldt-Universität zu Berlin, Institute of Biology-Plant Physiology, Philippstr. 13, Building 12, 10099 Berlin, Germany
| | - Bernhard Grimm
- Humboldt-Universität zu Berlin, Institute of Biology-Plant Physiology, Philippstr. 13, Building 12, 10099 Berlin, Germany
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Xiong B, Chen H, Ma Q, Yao J, Wang J, Wu W, Liao L, Wang X, Zhang M, He S, He J, Sun G, Wang Z. Genome-Wide Analysis of the GLK Gene Family and Its Expression at Different Leaf Ages in the Citrus Cultivar Kanpei. PLANTS (BASEL, SWITZERLAND) 2024; 13:936. [PMID: 38611466 PMCID: PMC11013922 DOI: 10.3390/plants13070936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024]
Abstract
The GLK gene family plays a crucial role in the regulation of chloroplast development and participates in chlorophyll synthesis. However, the precise mechanism by which GLK contributes to citrus's chlorophyll synthesis remains elusive. The GLK gene family causes variations in the photosynthetic capacity and chlorophyll synthesis of different citrus varieties. In this study, we identified tissue-specific members and the key CcGLKs involved in chlorophyll synthesis. A total of thirty CcGLK transcription factors (TFs) were discovered in the citrus genome, distributed across all nine chromosomes. The low occurrence of gene tandem duplication events and intronic variability suggests that intronic variation may be the primary mode of evolution for CcGLK TFs. Tissue-specific expression patterns were observed for various GLK family members; for instance, CcGLK12 and CcGLK15 were specifically expressed in the skin, while CcGLK30 was specific to the ovary, and CcGLK10, CcGLK6, CcGLK21, CcGLK2, CcGLK18, CcGLK9, CcGLK28, and CcGLK8 were specifically expressed in the leaves. CcGLK4, CcGLK5, CcGLK11, CcGLK23, CcGLKl7, CcGLK26, and CcGLK20 may participate in the regulation of the ALA, prochlorophylate, protoporphyrin IX, Mg-protoporphyrin IX, Chl b, T-Chl, MG-ProtoIX ME, and POR contents in citrus.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Zhihui Wang
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China; (B.X.); (H.C.); (Q.M.); (J.Y.); (J.W.); (W.W.); (L.L.); (X.W.); (M.Z.); (S.H.); (J.H.); (G.S.)
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5
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Liu T, Xu H, Amanullah S, Du Z, Hu X, Che Y, Zhang L, Jiang Z, Zhu L, Wang D. Deciphering the Enhancing Impact of Exogenous Brassinolide on Physiological Indices of Melon Plants under Downy Mildew-Induced Stress. PLANTS (BASEL, SWITZERLAND) 2024; 13:779. [PMID: 38592782 PMCID: PMC10974236 DOI: 10.3390/plants13060779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 04/11/2024]
Abstract
Melon (Cucumis melo L.) is a valuable horticultural crop of the Cucurbitaceae family. Downy mildew (DM), caused by Pseudoperonospora cubensis, is a significant inhibitor of the production and quality of melon. Brassinolide (BR) is a new type of phytohormone widely used in cultivation for its broad spectrum of resistance- and defense-mechanism-improving activity. In this study, we applied various exogenous treatments (0.5, 1.0, and 2.0 mg·L-1) of BR at four distinct time periods (6 h, 12 h, 24 h, and 48 h) and explored the impact of BR on physiological indices and the genetic regulation of melon seedling leaves infected by downy-mildew-induced stress. It was mainly observed that a 2.0 mg·L-1 BR concentration effectively promoted the enhanced photosynthetic activity of seedling leaves, and quantitative real-time polymerase chain reaction (qRT-PCR) analysis similarly exhibited an upregulated expression of the predicted regulatory genes of photosystem II (PSII) CmHCF136 (MELO3C023596.2) and CmPsbY (MELO3C010708.2), thus indicating the stability of the PSII reaction center. Furthermore, 2.0 mg·L-1 BR resulted in more photosynthetic pigments (nearly three times more than the chlorophyll contents (264.52%)) as compared to the control and other treatment groups and similarly upregulated the expression trend of the predicted key enzyme genes CmLHCP (MELO3C004214.2) and CmCHLP (MELO3C017176.2) involved in chlorophyll biosynthesis. Meanwhile, the maximum contents of soluble sugars and starch (186.95% and 164.28%) were also maintained, which were similarly triggered by the upregulated expression of the predicted genes CmGlgC (MELO3C006552.2), CmSPS (MELO3C020357.2), and CmPEPC (MELO3C018724.2), thereby maintaining osmotic adjustment and efficiency in eliminating reactive oxygen species. Overall, the exogenous 2.0 mg·L-1 BR exhibited maintained antioxidant activities, plastid membranal stability, and malondialdehyde (MDA) content. The chlorophyll fluorescence parameter values of F0 (42.23%) and Fv/Fm (36.67%) were also noticed to be higher; however, nearly three times higher levels of NPQ (375.86%) and Y (NPQ) (287.10%) were observed at 48 h of treatment as compared to all other group treatments. Increased Rubisco activity was also observed (62.89%), which suggested a significant role for elevated carbon fixation and assimilation and the upregulated expression of regulatory genes linked with Rubisco activity and the PSII reaction process. In short, we deduced that the 2.0 mg·L-1 BR application has an enhancing effect on the genetic modulation of physiological indices of melon plants against downy mildew disease stress.
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Affiliation(s)
- Tai Liu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Huichun Xu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Sikandar Amanullah
- College of Horticulture and Landscape Architecture, Northeast Agricultural University, Harbin 150030, China
- Key Laboratory of Biology and Genetic Improvement of Horticulture Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Northeast Agricultural University, Harbin 150030, China
| | - Zhiqiang Du
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Xixi Hu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Ye Che
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Ling Zhang
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Zeyu Jiang
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Lei Zhu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
| | - Di Wang
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (Y.C.); (L.Z.); (Z.J.); (L.Z.)
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6
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Han Y, Li F, Wu Y, Wang D, Luo G, Wang X, Wang X, Kuang H, Larkin RM. PSEUDO-ETIOLATION IN LIGHT proteins reduce greening by binding GLK transcription factors. PLANT PHYSIOLOGY 2024; 194:1722-1744. [PMID: 38051979 DOI: 10.1093/plphys/kiad641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/03/2023] [Accepted: 11/03/2023] [Indexed: 12/07/2023]
Abstract
Knocking out genes encoding proteins that downregulate the accumulation of pigments may lead to increases in crop quality and yield. PSEUDO-ETIOLATION IN LIGHT 1 (PEL1) downregulates the accumulation of carotenoids in carrot and chlorophyll in Arabidopsis and rice and may inhibit GOLDEN 2-LIKE (GLK) transcription factors. PEL1 belongs to a previously unstudied gene family found only in plants. We used CRISPR/Cas9 technology to knock out each member of the 4-member PEL gene family and both GLK genes in Arabidopsis. In pel mutants, chlorophyll levels were elevated in seedlings; after flowering, chloroplasts increased in size, and anthocyanin levels increased. Although the chlorophyll-deficient phenotype of glk1 glk2 was epistatic to pel1 pel2 pel3 pel4 in most of our experiments, glk1 glk2 was not epistatic to pel1 pel2 pel3 pel4 for the accumulation of anthocyanins in most of our experiments. The pel alleles attenuated growth, altered the accumulation of nutrients in seeds, disrupted an abscisic acid-inducible inhibition of seedling growth response that promotes drought tolerance, and affected the expression of genes associated with diverse biological functions, such as stress responses, cell wall metabolism hormone responses, signaling, growth, and the accumulation of phenylpropanoids and pigments. We found that PEL proteins specifically bind 6 transcription factors that influence the accumulation of anthocyanins, GLK2, and the carboxy termini of GLK1 and Arabidopsis thaliana myeloblastosis oncogene homolog 4 (AtMYB4). Our data indicate that the PEL proteins influence the accumulation of chlorophyll and many other processes, possibly by inhibiting GLK transcription factors and via other mechanisms, and that multiple mechanisms downregulate chlorophyll content.
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Affiliation(s)
- Yuting Han
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Fengfei Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Ying Wu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Dong Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Guangbao Luo
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Xinning Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Xin Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Hanhui Kuang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Robert M Larkin
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
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Yoshihara A, Kobayashi K, Nagata N, Fujii S, Wada H, Kobayashi K. Anionic lipids facilitate membrane development and protochlorophyllide biosynthesis in etioplasts. PLANT PHYSIOLOGY 2024; 194:1692-1704. [PMID: 37962588 PMCID: PMC10904342 DOI: 10.1093/plphys/kiad604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/18/2023] [Accepted: 10/16/2023] [Indexed: 11/15/2023]
Abstract
Dark-germinated angiosperm seedlings develop chloroplast precursors called etioplasts in cotyledon cells. Etioplasts develop lattice membrane structures called prolamellar bodies (PLBs), where the chlorophyll intermediate protochlorophyllide (Pchlide) forms a ternary complex with NADPH and light-dependent NADPH:Pchlide oxidoreductase (LPOR). The lipid bilayers of etioplast membranes are mainly composed of galactolipids, which play important roles in membrane-associated processes in etioplasts. Although etioplast membranes also contain 2 anionic lipids, phosphatidylglycerol (PG) and sulfoquinovosyldiacylglycerol (SQDG), their roles are unknown. To determine the roles of PG and SQDG in etioplast development, we characterized etiolated Arabidopsis (Arabidopsis thaliana) mutants deficient in PG and SQDG biosynthesis. A partial deficiency in PG biosynthesis loosened the lattice structure of PLBs and impaired the insertion of Mg2+ into protoporphyrin IX, leading to a substantial decrease in Pchlide content. Although a complete lack of SQDG biosynthesis did not notably affect PLB formation and Pchlide biosynthesis, lack of SQDG in addition to partial PG deficiency strongly impaired these processes. These results suggested that PG is required for PLB formation and Pchlide biosynthesis, whereas SQDG plays an auxiliary role in these processes. Notably, PG deficiency and lack of SQDG oppositely affected the dynamics of LPOR complexes after photoconversion, suggesting different involvements of PG and SQDG in LPOR complex organization. Our data demonstrate pleiotropic roles of anionic lipids in etioplast development.
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Affiliation(s)
- Akiko Yoshihara
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku,Sakai, Osaka 599-8531, Japan
| | - Keiko Kobayashi
- Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, Bunkyo-ku, Tokyo 112-8681, Japan
| | - Noriko Nagata
- Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, Bunkyo-ku, Tokyo 112-8681, Japan
| | - Sho Fujii
- Department of Biology, Faculty of Agriculture and Life Science, Hirosaki University, 1 Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan
| | - Hajime Wada
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Koichi Kobayashi
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku,Sakai, Osaka 599-8531, Japan
- Faculty of Liberal Arts, Science and Global Education, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
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8
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Wu YY, Wang LL, Lin YL, Li X, Liu XF, Xu ZH, Fu BL, Wang WQ, Allan AC, Tu MY, Yin XR. AcHZP45 is a repressor of chlorophyll biosynthesis and activator of chlorophyll degradation in kiwifruit. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:204-218. [PMID: 37712824 DOI: 10.1093/jxb/erad361] [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: 08/01/2023] [Accepted: 09/12/2023] [Indexed: 09/16/2023]
Abstract
The degradation of chlorophyll during fruit development is essential to reveal a more 'ripe' color that signals readiness to wild dispersers of seeds and the human consumer. Here, comparative biochemical analysis of developing fruit of Actinidia deliciosa cv. Xuxiang ('XX', green-fleshed) and Actinidia chinensis cv. Jinshi No.1 ('JS', yellow-fleshed) indicated that variation in chlorophyll content is the major contributor to differences in flesh color. Four differentially expressed candidate genes were identified: the down-regulated genes AcCRD1 and AcPOR1 involved in chlorophyll biosynthesis, and the up-regulated genes AcSGR1 and AcSGR2 driving chlorophyll degradation. Prochlorophyllide and chlorophyllide, the metabolites produced by AcCRD1 and AcPOR1, progressively reduced in 'JS', but not in 'XX', indicating that chlorophyll biosynthesis was less active in yellow-fleshed fruit. AcSGR1 and AcSGR2 were verified to be involved in chlorophyll degradation, using both transient expression in tobacco and stable overexpression in kiwifruit. Furthermore, a homeobox-leucine zipper (HD-Zip II), AcHZP45, showed significantly increased expression during 'JS' fruit ripening, which led to both repressed expression of AcCRD1 and AcPOR1 and activated expression of AcSGR1 and AcSGR2. Collectively, the present study indicated that different dynamics of chlorophyll biosynthesis and degradation coordinate the changes in chlorophyll content in kiwifruit flesh, which are orchestrated by the key transcription factor AcHZP45.
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Affiliation(s)
- Ying-Ying Wu
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Ling-Li Wang
- Horticulture Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu 610066, China
- Key Laboratory of Horticultural Crop Biology and Germplasm Creation in Southwestern China, Ministry of Agriculture and Rural Affairs, Chengdu 610066, China
| | - Yi-Lai Lin
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Xiang Li
- School of Horticulture, Anhui Agricultural University, Hefei 230036, China
| | - Xiao-Fen Liu
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Zi-Hong Xu
- Horticulture Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu 610066, China
- Key Laboratory of Horticultural Crop Biology and Germplasm Creation in Southwestern China, Ministry of Agriculture and Rural Affairs, Chengdu 610066, China
| | - Bei-Ling Fu
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Wen-Qiu Wang
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Andrew C Allan
- The New Zealand Institute for Plant & Food Research Limited (Plant & Food Research) Mt Albert, Private Bag 92169, Auckland 1142, New Zealand
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Mei-Yan Tu
- Horticulture Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu 610066, China
- Key Laboratory of Horticultural Crop Biology and Germplasm Creation in Southwestern China, Ministry of Agriculture and Rural Affairs, Chengdu 610066, China
| | - Xue-Ren Yin
- Horticulture Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
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9
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Zhang H, Zhang W, Xiang F, Zhang Z, Guo Y, Chen T, Duan F, Zhou Q, Li X, Fang M, Li X, Li B, Zhao X. Photosynthetic characteristics and genetic mapping of a new yellow leaf mutant crm1 in Brassica napus. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2023; 43:80. [PMID: 37954030 PMCID: PMC10635920 DOI: 10.1007/s11032-023-01429-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/31/2023] [Indexed: 11/14/2023]
Abstract
Chlorophyll is one of the key factors for photosynthesis and plays an important role in plant growth and development. We previously isolated an EMS mutagenized rapeseed chlorophyll-reduced mutant (crm1), which had yellow leaf, reduced chlorophyll content and fewer thylakoid stacks. Here, we found that crm1 showed attenuated utilization efficiency of both light energy and CO2 but enhanced heat dissipation efficiency and greater tolerance to high-light intensity. BSA-Seq analysis identified a single nucleotide change (C to T) and (G to A) in the third exon of the BnaA01G0094500ZS and BnaC01G0116100ZS, respectively. These two genes encode the magnesium chelatase subunit I 1 (CHLI1) that catalyzes the insertion of magnesium into protoporphyrin IX, a pivotal step in chlorophyll synthesis. The mutation sites resulted in an amino acid substitution P144S and G128E within the AAA+ domain of the CHLI1 protein. Two KASP markers were developed and co-segregated with the yellow leaf phenotype in segregating F2 population. Loss of BnaA01.CHLI1 and BnaC01.CHLI1 by CRISPR/Cas9 gene editing recapitulated the mutant phenotype. BnaA01.CHLI1 and BnaC01.CHLI1 were located in chloroplast and highly expressed in the leaves. Furthermore, RNA-seq analyses revealed the expression of chlorophyll synthesis-related genes were upregulated in the crm1 mutant. These findings provide a new insight into the regulatory mechanism of chlorophyll synthesis in rapeseed and suggest a novel target for improving the photosynthetic efficiency and tolerance to high-light intensity in crops. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-023-01429-6.
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Affiliation(s)
- Hui Zhang
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125 China
| | - Wei Zhang
- College of Agronomy, Hunan Agricultural University, Changsha, 410128 Hunan China
| | - Fujiang Xiang
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | - Zhengfeng Zhang
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | - Yiming Guo
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125 China
| | - Tingzhou Chen
- Hunan Cotton Research Institute, Changde, 415100 Hunan China
| | - Feifei Duan
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | - Quanyu Zhou
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | - Xin Li
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | | | - Xinmei Li
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
| | - Bao Li
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125 China
| | - Xiaoying Zhao
- College of Biology, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan University, Changsha, 410082 China
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10
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Tournaire MD, Scharff LB, Kramer M, Goss T, Vuorijoki L, Rodriguez‐Heredia M, Wilson S, Kruse I, Ruban A, Balk L. J, Hase T, Jensen P, Hanke GT. Ferredoxin C2 is required for chlorophyll biosynthesis and accumulation of photosynthetic antennae in Arabidopsis. PLANT, CELL & ENVIRONMENT 2023; 46:3287-3304. [PMID: 37427830 PMCID: PMC10947542 DOI: 10.1111/pce.14667] [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: 03/22/2023] [Revised: 06/09/2023] [Accepted: 06/22/2023] [Indexed: 07/11/2023]
Abstract
Ferredoxins (Fd) are small iron-sulphur proteins, with sub-types that have evolved for specific redox functions. Ferredoxin C2 (FdC2) proteins are essential Fd homologues conserved in all photosynthetic organisms and a number of different FdC2 functions have been proposed in angiosperms. Here we use RNAi silencing in Arabidopsis thaliana to generate a viable fdC2 mutant line with near-depleted FdC2 protein levels. Mutant leaves have ~50% less chlorophyll a and b, and chloroplasts have poorly developed thylakoid membrane structure. Transcriptomics indicates upregulation of genes involved in stress responses. Although fdC2 antisense plants show increased damage at photosystem II (PSII) when exposed to high light, PSII recovers at the same rate as wild type in the dark. This contradicts literature proposing that FdC2 regulates translation of the D1 subunit of PSII, by binding to psbA transcript. Measurement of chlorophyll biosynthesis intermediates revealed a build-up of Mg-protoporphyrin IX, the substrate of the aerobic cyclase. We localise FdC2 to the inner chloroplast envelope and show that the FdC2 RNAi line has a disproportionately lower protein abundance of antennae proteins, which are nuclear-encoded and must be refolded at the envelope after import.
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Affiliation(s)
| | - Lars B. Scharff
- Department of Plant and Environmental Sciences, Copenhagen Plant Science CentreUniversity of CopenhagenFrederiksbergDenmark
| | - Manuela Kramer
- School of Biological and Behavioural sciencesQueen Mary University of LondonLondonUK
| | - Tatjana Goss
- Department of Plant PhysiologyOsnabrück UniversityOsnabrückGermany
| | | | | | - Sam Wilson
- School of Biological and Behavioural sciencesQueen Mary University of LondonLondonUK
| | - Inga Kruse
- Department of Plant PhysiologyOsnabrück UniversityOsnabrückGermany
| | - Alexander Ruban
- School of Biological and Behavioural sciencesQueen Mary University of LondonLondonUK
| | | | - Toshiharu Hase
- Institute for Protein ResearchOsaka UniversityOsakaJapan
| | - Poul‐Erik Jensen
- Department of Food ScienceUniversity of CopenhagenFrederiksbergDenmark
| | - Guy T. Hanke
- School of Biological and Behavioural sciencesQueen Mary University of LondonLondonUK
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11
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Ji S, Grimm B, Wang P. Chloroplast SRP43 and SRP54 independently promote thermostability and membrane binding of light-dependent protochlorophyllide oxidoreductases. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1583-1598. [PMID: 37269173 DOI: 10.1111/tpj.16339] [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: 02/22/2023] [Revised: 04/18/2023] [Accepted: 05/22/2023] [Indexed: 06/04/2023]
Abstract
Protochlorophyllide oxidoreductase (POR), which converts protochlorophyllide into chlorophyllide, is the only light-dependent enzyme in chlorophyll biosynthesis. While its catalytic reaction and importance for chloroplast development are well understood, little is known about the post-translational control of PORs. Here, we show that cpSRP43 and cpSRP54, two components of the chloroplast signal recognition particle pathway, play distinct roles in optimizing the function of PORB, the predominant POR isoform in Arabidopsis. The chaperone cpSRP43 stabilizes the enzyme and provides appropriate amounts of PORB during leaf greening and heat shock, whereas cpSRP54 enhances its binding to the thylakoid membrane, thereby ensuring adequate levels of metabolic flux in late chlorophyll biosynthesis. Furthermore, cpSRP43 and the DnaJ-like protein CHAPERONE-LIKE PROTEIN of POR1 concurrently act to stabilize PORB. Overall, these findings enhance our understanding of the coordinating role of cpSPR43 and cpSRP54 in the post-translational control of chlorophyll synthesis and assembly of photosynthetic chlorophyll-binding proteins.
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Affiliation(s)
- Shuiling Ji
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Philippstr.13, Building 12, 10099, Berlin, Germany
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, 430079, Wuhan, China
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Philippstr.13, Building 12, 10099, Berlin, Germany
| | - Peng Wang
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Philippstr.13, Building 12, 10099, Berlin, Germany
- School of Biological Sciences, The University of Hong Kong, Hong Kong, 999077, China
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, 999077, Hong Kong, China
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12
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Liu T, Amanullah S, Xu H, Gao P, Du Z, Hu X, Han M, Che Y, Zhang L, Qi G, Wang D. RNA-Seq Identified Putative Genes Conferring Photosynthesis and Root Development of Melon under Salt Stress. Genes (Basel) 2023; 14:1728. [PMID: 37761868 PMCID: PMC10530605 DOI: 10.3390/genes14091728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/22/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023] Open
Abstract
Melon is an important fruit crop of the Cucurbitaceae family that is being cultivated over a large area in China. Unfortunately, salt stress has crucial effects on crop plants and damages photosynthesis, membranal lipid components, and hormonal metabolism, which leads to metabolic imbalance and retarded growth. Herein, we performed RNA-seq analysis and a physiological parameter evaluation to assess the salt-induced stress impact on photosynthesis and root development activity in melon. The endogenous quantification analysis showed that the significant oxidative damage in the membranal system resulted in an increased ratio of non-bilayer/bilayer lipid (MGDG/DGDG), suggesting severe irregular stability in the photosynthetic membrane. Meanwhile, root development was slowed down by a superoxidized membrane system, and downregulated genes showed significant contributions to cell wall biosynthesis and IAA metabolism. The comparative transcriptomic analysis also exhibited that major DEGs were more common in the intrinsic membrane component, photosynthesis, and metabolism. These are all processes that are usually involved in negative responses. Further, the WGCN analysis revealed the involvement of two main network modules: the thylakoid membrane and proteins related to photosystem II. The qRT-PCR analysis exhibited that two key genes (MELO3C006053.2 and MELO3C023596.2) had significant variations in expression profiling at different time intervals of salt stress treatments (0, 6, 12, 24, and 48 h), which were also consistent with the RNA-seq results, denoting the significant accuracy of molecular dataset analysis. In summary, we performed an extensive molecular and metabolic investigation to check the salt-stress-induced physiological changes in melon and proposed that the PSII reaction centre may likely be the primary stress target.
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Affiliation(s)
- Tai Liu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Sikandar Amanullah
- Key Laboratory of Biology and Genetic Improvement of Horticulture Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Northeast Agricultural University, Harbin 150030, China; (S.A.); (P.G.)
- College of Horticulture and Landscape Architecture, Northeast Agricultural University, Harbin 150030, China
| | - Huichun Xu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Peng Gao
- Key Laboratory of Biology and Genetic Improvement of Horticulture Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Northeast Agricultural University, Harbin 150030, China; (S.A.); (P.G.)
- College of Horticulture and Landscape Architecture, Northeast Agricultural University, Harbin 150030, China
| | - Zhiqiang Du
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Xixi Hu
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Mo Han
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Ye Che
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Ling Zhang
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Guochao Qi
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
| | - Di Wang
- Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163711, China; (T.L.); (H.X.); (Z.D.); (X.H.); (M.H.); (Y.C.); (L.Z.); (G.Q.)
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13
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Liu X, Cao J, Cheng X, Zhu W, Sun Y, Wan X, Liu L. CsRVE1 promotes seasonal greening of albino Camellia sinensis cv. Huangkui by activating chlorophyll biosynthesis. TREE PHYSIOLOGY 2023; 43:1432-1443. [PMID: 37083709 DOI: 10.1093/treephys/tpad052] [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: 09/27/2022] [Revised: 03/08/2023] [Accepted: 04/13/2023] [Indexed: 05/03/2023]
Abstract
Seasonal greening is a crucial survival strategy for albino tea cultivars, during which dysfunctional chloroplasts recover and chlorophyll biosynthesis increases in albino leaves. However, the regulatory mechanisms of seasonal greening in albino tea plants remain unclear. Here, we report that CsRVE1, a nuclear-located Myb-like transcription factor, can positively modulate the seasonal greening of albino Camellia sinensis cv. Huangkui leaves by activating the expression of genes involved in light harvesting and chlorophyll biosynthesis. The transcriptional expression of CsRVE1 increased during seasonal greening and was tightly correlated with increases in the expression of genes involved in light harvesting (CsLhcb) and chlorophyll biosynthesis (CsCHLH, CsHEMA1 and CsCAO). In vivo and in vitro molecular analyses showed that CsRVE1 can directly bind to the promoters of CsLhcb, CsCHLH and CsPORA, eventually leading to chlorophyll accumulation in tea leaves. Furthermore, transient suppression of CsRVE1 in tea leaves led to a decrease in target gene expression. In contrast, the overexpression of CsRVE1 in Arabidopsis led to chlorophyll increases and the activation of AtLhcb, AtPORA, AtCHLH, etc. These results identify CsRVE1 as an important promoter of seasonal greening that functions by regulating genes involved in chlorophyll biosynthesis in albino tea plants and shed new light on the regulatory mechanisms of leaf phenotypes in plants.
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Affiliation(s)
- Xuyang Liu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Jingjie Cao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Xin Cheng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Wenfeng Zhu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Ying Sun
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
| | - Linlin Liu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, West 130 Changjiang Road, Hefei, Anhui 230036, China
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14
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Zhang X, Zhao Z, Zhang M, Wang J, Cheng T, Zhang Q, Pan H. FsHemF is involved in the formation of yellow Forsythia leaves by regulating chlorophyll synthesis in response to light intensity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 200:107746. [PMID: 37210861 DOI: 10.1016/j.plaphy.2023.107746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/21/2023] [Accepted: 05/04/2023] [Indexed: 05/23/2023]
Abstract
The leaves of Forsythia koreana 'Suwon Gold' are yellow under natural light condition and can revert to green when the light intensity is reduced. To understand the molecular mechanism of leaf color changes in response to light intensity, we compared the chlorophyll content and precursor content between yellow- and green-leaf Forsythia under shade and light-recovery conditions. We identified the conversion of coproporphyrin III (Coprogen III) to protoporphyrin IX (Proto IX) as the primary rate-limiting step of chlorophyll biosynthesis in yellow-leaf Forsythia. Further analysis of the activity of the enzymes that catalyze this step and the expression pattern of the chlorophyll biosynthesis-related genes under different light intensities revealed that the negatively regulated expression of FsHemF by light intensity was the major cause affecting the leaf color change in response to light intensity in yellow-leaf Forsythia. To further understand the cause of differential expression pattern of FsHemF in yellow- and green-leaf lines, we compared the coding sequence and promoter sequence of FsHemF between yellow- and green-leaf Forsythia. We found that one G-box light-responsive cis-element was absent in the promoter region of green-leaf lines. To investigate the functional role of FsHemF, we performed virus-induced gene silencing (VIGS) of FsHemF in green-leaf Forsythia, which leads to yellowing leaf veins, decreased chlorophyll b content, and inhibition of chlorophyll biosynthesis. The results will assist in elucidating the mechanism of yellow-leaf Forsythia in response to light intensity.
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Affiliation(s)
- Xiaolu Zhang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Zhengtian Zhao
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Man Zhang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Jia Wang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Tangren Cheng
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Qixiang Zhang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Huitang Pan
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China.
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15
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Han H, Zhou Y, Liu H, Chen X, Wang Q, Zhuang H, Sun X, Ling Q, Zhang H, Wang B, Wang J, Tang Y, Wang H, Liu H. Transcriptomics and Metabolomics Analysis Provides Insight into Leaf Color and Photosynthesis Variation of the Yellow-Green Leaf Mutant of Hami Melon ( Cucumis melo L.). PLANTS (BASEL, SWITZERLAND) 2023; 12:1623. [PMID: 37111847 PMCID: PMC10143263 DOI: 10.3390/plants12081623] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 06/16/2023]
Abstract
Leaf color mutants are ideal materials for studying the regulatory mechanism of chloroplast development and photosynthesis. We isolated a cucumis melo spontaneous mutant (MT), which showed yellow-green leaf phenotype in the whole growing period and could be inherited stably. We compared its leaves with the wild type (WT) in terms of cytology, physiology, transcriptome and metabolism. The results showed that the thylakoid grana lamellae of MT were loosely arranged and fewer in number than WT. Physiological experiments also showed that MT had less chlorophyll content and more accumulation of reactive oxygen species (ROS) than WT. Furthermore, the activity of several key enzymes in C4 photosynthetic carbon assimilation pathway was more enhanced in MT than WT. Transcriptomic and metabolomic analyses showed that differential expression genes and differentially accumulated metabolites in MT were mainly co-enriched in the pathways related to photosystem-antenna proteins, central carbon metabolism, glutathione metabolism, phenylpropanoid biosynthesis and flavonoid metabolism. We also analyzed several key proteins in photosynthesis and chloroplast transport by Western blot. In summary, the results may provide a new insight into the understanding of how plants respond to the impaired photosynthesis by regulating chloroplast development and photosynthetic carbon assimilation pathways.
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Affiliation(s)
- Hongwei Han
- Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Corps, Department of Horticulture, College of Agriculture, Shihezi University, Shihezi 832003, China; (H.H.)
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Yuan Zhou
- 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 200030, China
| | - Huifang Liu
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Xianjun Chen
- Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Corps, Department of Horticulture, College of Agriculture, Shihezi University, Shihezi 832003, China; (H.H.)
| | - Qiang Wang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Hongmei Zhuang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Xiaoxia Sun
- Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Corps, Department of Horticulture, College of Agriculture, Shihezi University, Shihezi 832003, China; (H.H.)
| | - Qihua Ling
- 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 200030, China
| | - Huijun Zhang
- School of Life Science, Huaibei Normal University, Huaibei 235000, China
| | - Baike Wang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Juan Wang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Yaping Tang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Hao Wang
- Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Institute of Horticultural Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830002, China
| | - Huiying Liu
- Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Corps, Department of Horticulture, College of Agriculture, Shihezi University, Shihezi 832003, China; (H.H.)
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16
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Yuan Y, Li X, Yao X, Fu X, Cheng J, Shan H, Yin X, Kong H. Mechanisms underlying the formation of complex color patterns on Nigella orientalis (Ranunculaceae) petals. THE NEW PHYTOLOGIST 2023; 237:2450-2466. [PMID: 36527229 DOI: 10.1111/nph.18681] [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: 10/05/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
Complex color patterns on petals are widespread in flowering plants, yet the mechanisms underlying their formation remain largely unclear. Here, by conducting detailed morphological, anatomical, biochemical, optical, transcriptomic, and functional studies, we investigated the cellular bases, chromogenic substances, reflectance spectra, developmental processes, and underlying mechanisms of complex color pattern formation on Nigella orientalis petals. We found that the complexity of the N. orientalis petals in color pattern is reflected at multiple levels, with the amount and arrangement of different pigmented cells being the key. We also found that biosynthesis of the chromogenic substances of different colors is sequential, so that one color/pattern is superimposed on another. Expression and functional studies further revealed that a pair of R2R3-MYB genes function cooperatively to specify the formation of the eyebrow-like horizontal stripe and the Mohawk haircut-like splatters. Specifically, while NiorMYB113-1 functions to draw a large splatter region, NiorMYB113-2 functions to suppress the production of anthocyanins from the region where a gap will form, thereby forming the highly specialized pattern. Our results provide a detailed portrait for the spatiotemporal dynamics of the coloration of N. orientalis petals and help better understand the mechanisms underlying complex color pattern formation in plants.
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Affiliation(s)
- Yi Yuan
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- China National Botanical Garden, Beijing, 100093, China
| | - Xuan Li
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- China National Botanical Garden, Beijing, 100093, China
| | - Xu Yao
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- China National Botanical Garden, Beijing, 100093, China
| | - Xuehao Fu
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- China National Botanical Garden, Beijing, 100093, China
| | - Jie Cheng
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- China National Botanical Garden, Beijing, 100093, China
| | - Hongyan Shan
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- China National Botanical Garden, Beijing, 100093, China
| | - Xiaofeng Yin
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- China National Botanical Garden, Beijing, 100093, China
| | - Hongzhi Kong
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- China National Botanical Garden, Beijing, 100093, China
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17
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Li Y, Liu H, Ma T, Li J, Yuan J, Xu YC, Sun R, Zhang X, Jing Y, Guo YL, Lin R. Arabidopsis EXECUTER1 interacts with WRKY transcription factors to mediate plastid-to-nucleus singlet oxygen signaling. THE PLANT CELL 2023; 35:827-851. [PMID: 36423342 PMCID: PMC9940883 DOI: 10.1093/plcell/koac330] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 10/10/2022] [Accepted: 11/16/2022] [Indexed: 06/01/2023]
Abstract
Chloroplasts produce singlet oxygen (1O2), which causes changes in nuclear gene expression through plastid-to-nucleus retrograde signaling to increase plant fitness. However, the identity of this 1O2-triggered pathway remains unclear. Here, we identify mutations in GENOMES UNCOUPLED4 (GUN4) and GUN5 as suppressors of phytochrome-interacting factor1 (pif1) pif3 in regulating the photo-oxidative response in Arabidopsis thaliana. GUN4 and GUN5 specifically interact with EXECUTER1 (EX1) and EX2 in plastids, and this interaction is alleviated by treatment with Rose Bengal (RB) or white light. Impaired expression of GUN4, GUN5, EX1, or EX2 leads to insensitivity to excess light and overexpression of EX1 triggers photo-oxidative responses. Strikingly, upon light irradiation or RB treatment, EX1 transiently accumulates in the nucleus and the nuclear fraction of EX1 shows a similar molecular weight as the plastid-located protein. Point mutagenesis analysis indicated that nuclear localization of EX1 is required for its function. EX1 acts as a transcriptional co-activator and interacts with the transcription factors WRKY18 and WRKY40 to promote the expression of 1O2-responsive genes. This study suggests that EX1 may act in plastid-to-nucleus signaling and establishes a 1O2-triggered retrograde signaling pathway that allows plants adapt to changing light environments during chloroplast development.
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Affiliation(s)
- Yuhong Li
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanhong Liu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tingting Ma
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jialong Li
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jiarui Yuan
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong-Chao Xu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Ran Sun
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinyu Zhang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Yanjun Jing
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Ya-Long Guo
- University of Chinese Academy of Sciences, Beijing 100049, China
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Rongcheng Lin
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Srivastava R, Kobayashi Y, Koyama H, Sahoo L. Cowpea NAC1/NAC2 transcription factors improve growth and tolerance to drought and heat in transgenic cowpea through combined activation of photosynthetic and antioxidant mechanisms. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:25-44. [PMID: 36107155 DOI: 10.1111/jipb.13365] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 09/13/2022] [Indexed: 06/15/2023]
Abstract
NAC (NAM/ATAF1/2/CUC2) transcription factors are central switches of growth and stress responses in plants. However, unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC orthologs inapt for pulse engineering. The knowledge of suitable NAC candidates in hardy pulses like cowpea (Vigna unguiculata (L.) Walp.) is still in infancy, hence warrants immediate biotechnological intervention. Here, we showed that overexpression of two native NAC genes (VuNAC1 and VuNAC2) promoted germinative, vegetative, and reproductive growth and conferred multiple abiotic stress tolerance in a commercial cowpea variety. The transgenic lines displayed increased leaf area, thicker stem, nodule-rich denser root system, early flowering, higher pod production (∼3.2-fold and ∼2.1-fold), and greater seed weight (10.3% and 6.0%). In contrast, transient suppression of VuNAC1/2 caused severe growth retardation and flower inhibition. The overexpressor lines showed remarkable tolerance to major yield-declining terminal stresses, such as drought, salinity, heat, and cold, and recovered growth and seed production by boosting photosynthetic activity, water use efficiency, membrane integrity, Na+ /K+ homeostasis, and antioxidant activity. The comparative transcriptome study indicated consolidated activation of genes involved in chloroplast development, photosynthetic complexes, cell division and expansion, cell wall biogenesis, nutrient uptake and metabolism, stress response, abscisic acid, and auxin signaling. Unlike their orthologs, VuNAC1/2 direct synergistic transcriptional tuning of stress and developmental signaling to avoid unwanted trade-offs. Their overexpression governs the favorable interplay of photosynthesis and reactive oxygen species regulation to improve stress recovery, nutritional sufficiency, biomass, and production. This unconventional balance of strong stress tolerance and agronomic quality is useful for translational crop research and molecular breeding of pulses.
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Affiliation(s)
- Richa Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Yuriko Kobayashi
- Faculty of Applied Biological Sciences, Gifu University, 1-1, Yanagido, Gifu, 501-1193,, Japan
| | - Hiroyuki Koyama
- Faculty of Applied Biological Sciences, Gifu University, 1-1, Yanagido, Gifu, 501-1193,, Japan
| | - Lingaraj Sahoo
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
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19
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Luo WG, Liang QW, Su Y, Huang C, Mo BX, Yu Y, Xiao LT. Auxin inhibits chlorophyll accumulation through ARF7-IAA14-mediated repression of chlorophyll biosynthesis genes in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2023; 14:1172059. [PMID: 37152161 PMCID: PMC10157223 DOI: 10.3389/fpls.2023.1172059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 04/06/2023] [Indexed: 05/09/2023]
Abstract
Auxin is a well-known important phytohormone in plant that plays vital roles in almost every development process throughout plant lifecycle. However, the effect of auxin on the metabolism of chlorophyll, one of the most important pigments involved in the photosynthesis, was intertwined and the underlying mechanism remained to be explored. Here, we found the auxin-defective yuc2 yuc6 double mutant displayed dark-green leaf color with higher chlorophyll content than wildtype, suggesting a negative regulatory role of auxin in chlorophyll biosynthesis. The chloroplast number and structure in mesophyll cells were altered and the photosynthetic efficiency was improved in yuc2 yuc6. In addition, the chlorophyll level was significantly improved during seedling de-etiolation in yuc2 yuc6 mutant, and decreased dramatically under IAA treatment, confirming the inhibitory role of auxin in chlorophyll biosynthesis. The analyses of gene expression in mature leaves and de-etiolation seedlings suggested that auxin suppressed the expression of many chlorophyll biosynthesis genes, especially PROTOCHLOROPHYLLIDE OXIDOREDUCTASE A (PORA) and GENOMES UNCOUPLED 5 (GUN5). Yeast-one-hybrid and luciferase assays demonstrated that the AUXIN RESPONSE FACTOR 2 (ARF2) and ARF7 bind to the promoter of PORA and GUN5 to suppress their expression with the help of INDOLE-3-ACETIC ACID14 (IAA14). Collectively, our research explicitly unraveled the direct inhibitory role of auxin in chlorophyll biosynthesis, and provided new insight into the interplay between auxin signaling and chlorophyll metabolism.
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Affiliation(s)
- Wei-Gui Luo
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
| | - Qi-Wen Liang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
| | - Yi Su
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
| | - Chao Huang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
| | - Bei-Xin Mo
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Yu Yu
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- *Correspondence: Lang-Tao Xiao, ; Yu Yu,
| | - Lang-Tao Xiao
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
- *Correspondence: Lang-Tao Xiao, ; Yu Yu,
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20
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Pagani MA, Gomez-Casati DF. Advances in Iron Retrograde Signaling Mechanisms and Uptake Regulation in Photosynthetic Organisms. Methods Mol Biol 2023; 2665:121-145. [PMID: 37166598 DOI: 10.1007/978-1-0716-3183-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Iron (Fe) is an essential metal for the growth and development of different organisms, including plants and algae. This metal participates in different biological processes, among which are cellular respiration and photosynthesis. Fe is found associated with heme groups and as part of inorganic Fe-S groups as cofactors of numerous cellular proteins. Although Fe is abundant in soils, it is often not bioavailable due to soil pH. For this reason, photosynthetic organisms have developed different strategies for the uptake, the sensing of Fe intracellular levels but also different mechanisms that maintain and regulate adequate concentrations of this metal in response to physiological needs. This work focuses on discussing recent advances in the characterization of the mechanisms of Fe homeostasis and Fe retrograde signaling in photosynthetic organisms.
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Affiliation(s)
- Maria A Pagani
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario, Rosario, Argentina.
| | - Diego F Gomez-Casati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario, Rosario, Argentina.
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21
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Balakhonova V, Dobisova T, Benedikty Z, Panzarova K, Pytela J, Koci R, Spyroglou I, Kovacova I, Arnaud D, Skalak J, Trtilek M, Hejatko J. iReenCAM: automated imaging system for kinetic analysis of photosynthetic pigment biosynthesis at high spatiotemporal resolution during early deetiolation. FRONTIERS IN PLANT SCIENCE 2023; 14:1093292. [PMID: 37152154 PMCID: PMC10160634 DOI: 10.3389/fpls.2023.1093292] [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: 11/08/2022] [Accepted: 04/04/2023] [Indexed: 05/09/2023]
Abstract
Seedling de-etiolation is one of the key stages of the plant life cycle, characterized by a strong rearrangement of the plant development and metabolism. The conversion of dark accumulated protochlorophyllide to chlorophyll in etioplasts of de-etiolating plants is taking place in order of ns to µs after seedlings illumination, leading to detectable increase of chlorophyll levels in order of minutes after de-etiolation initiation. The highly complex chlorophyll biosynthesis integrates number of regulatory events including light and hormonal signaling, thus making de-etiolation an ideal model to study the underlying molecular mechanisms. Here we introduce the iReenCAM, a novel tool designed for non-invasive fluorescence-based quantitation of early stages of chlorophyll biosynthesis during de-etiolation with high spatial and temporal resolution. iReenCAM comprises customized HW configuration and optimized SW packages, allowing synchronized automated measurement and analysis of the acquired fluorescence image data. Using the system and carefully optimized protocol, we show tight correlation between the iReenCAM monitored fluorescence and HPLC measured chlorophyll accumulation during first 4h of seedling de-etiolation in wild type Arabidopsis and mutants with disturbed chlorophyll biosynthesis. Using the approach, we demonstrate negative effect of exogenously applied cytokinins and ethylene on chlorophyll biosynthesis during early de-etiolation. Accordingly, we identify type-B response regulators, the cytokinin-responsive transcriptional activators ARR1 and ARR12 as negative regulators of early chlorophyll biosynthesis, while contrasting response was observed in case of EIN2 and EIN3, the components of canonical ethylene signaling cascade. Knowing that, we propose the use of iReenCAM as a new phenotyping tool, suitable for quantitative and robust characterization of the highly dynamic response of seedling de-etiolation.
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Affiliation(s)
- Veronika Balakhonova
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
| | - Tereza Dobisova
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
| | | | | | | | - Radka Koci
- Photon Systems Instruments, Drasov, Czechia
| | - Ioannis Spyroglou
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Ingrid Kovacova
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Dominique Arnaud
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Jan Skalak
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
| | | | - Jan Hejatko
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czechia
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- *Correspondence: Jan Hejatko,
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22
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Liu M, Ma W, Su X, Zhang X, Lu Y, Zhang S, Yan J, Feng D, Ma L, Taylor A, Ge Y, Cheng Q, Xu K, Wang Y, Li N, Gu A, Zhang J, Luo S, Xuan S, Chen X, Scrutton NS, Li C, Zhao J, Shen S. Mutation in a chlorophyll-binding motif of Brassica ferrochelatase enhances both heme and chlorophyll biosynthesis. Cell Rep 2022; 41:111758. [PMID: 36476857 DOI: 10.1016/j.celrep.2022.111758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 09/06/2022] [Accepted: 11/09/2022] [Indexed: 12/12/2022] Open
Abstract
The heme branch of tetrapyrrole biosynthesis contributes to the regulation of chlorophyll levels. However, the mechanism underlying the balance between chlorophyll and heme synthesis remains elusive. Here, we identify a dark green leaf mutant, dg, from an ethyl methanesulfonate (EMS)-induced mutant library of Chinese cabbage. The dg phenotype is caused by an amino acid substitution in the conserved chlorophyll a/b-binding motif (CAB) of ferrochelatase 2 (BrFC2). This mutation increases the formation of BrFC2 homodimer to promote heme production. Moreover, wild-type BrFC2 and dBrFC2 interact with protochlorophyllide (Pchlide) oxidoreductase B1 and B2 (BrPORB1 and BrPORB2), and dBrFC2 exhibits higher binding ability to substrate Pchlide, thereby promoting BrPORBs-catalyzed production of chlorophyllide (Chlide), which can be directly converted into chlorophyll. Our results show that dBrFC2 is a gain-of-function mutation contributing to balancing heme and chlorophyll synthesis via a regulatory mechanism in which dBrFC2 promotes BrPORB enzymatic reaction to enhance chlorophyll synthesis.
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Affiliation(s)
- Mengyang Liu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Wei Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiangjie Su
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiaomeng Zhang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Yin Lu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Shaowei Zhang
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Jinghui Yan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Daling Feng
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Lisong Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Aoife Taylor
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Yunjia Ge
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Qi Cheng
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Kedong Xu
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China
| | - Yanhua Wang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Na Li
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Aixia Gu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Ju Zhang
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China
| | - Shuangxia Luo
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Shuxin Xuan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xueping Chen
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Chengwei Li
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China.
| | - Jianjun Zhao
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
| | - Shuxing Shen
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
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23
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Genome-Wide Identification and Expression Analysis of Senescence-Associated Genes in Grapevine ( Vitis vinifera L.) Reveal Their Potential Functions in Leaf Senescence Order. Int J Mol Sci 2022; 23:ijms232112731. [PMID: 36361520 PMCID: PMC9656468 DOI: 10.3390/ijms232112731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 10/07/2022] [Accepted: 10/08/2022] [Indexed: 01/25/2023] Open
Abstract
Natural leaf senescence is an acclimation strategy that enables plants to reallocate nutrients. In the present study, interestingly, we found that the basal mature leaves of grapevine primary shoots (P) exhibited the earliest senescence, followed by the apical young leaves of secondary shoots (ST), and then the basal mature leaves of secondary shoots (S). The Chl level decreased with the extent of leaf senescence. According to the genome-wide identification and expression analysis, sixteen senescence-associated genes (SAGs) involved in Chl breakdown were identified in the grapevine genome. Their expression patterns showed that the transcript changes in VvSGR, VvPPH2, and VvFtsH6-2 corresponded to the changes in Chl content among P, S, and ST. The changes in the transcription of VvNYC1, VvSGR, VvPAO1, VvPAO2, VvPAO4, VvPPH1, VvPPH3, and VvFtsH6-1 only contributed to low Chl levels in P. The cis-element analysis indicated that these SAGs possessed several light- and hormone-responsive elements in their promoters. Among them, ABA-responsive elements were found in twelve of the sixteen promoters of SAGs. Correspondingly, ABA-signaling components presented various changes in transcription among P, S, and ST. The transcription changes in VvbZIP45 and VvSnRK2.1 were similar to those in VvSGR, VvPPH2, and VvFtsH6-2. The other nine ABA-signaling components, which included VvRCAR2, VvRCAR4, VvRCAR6, VvRCAR7, VvRCAR2, VvPP2C4, VvPP2C9, VvbZIP25, and VvSnRK2.3, were highly expressed in P but there was no difference between S and ST, with similar expression patterns for VvNYC1, VvSGR, VvPAO1, VvPAO2, VvPAO4, VvPPH1, VvPPH3, and VvFtsH6-1. These results suggested that the senescence of P and ST could be regulated by different members of Chl breakdown-related SAGs and ABA-signaling components. These findings provide us with important candidate genes to further study the regulation mechanism of leaf senescence order in grapevine.
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24
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Bakirbas A, Walker EL. CAN OF SPINACH, a novel long non-coding RNA, affects iron deficiency responses in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:1005020. [PMID: 36275516 PMCID: PMC9581158 DOI: 10.3389/fpls.2022.1005020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Long non-coding RNAs (lncRNAs) are RNA molecules with functions independent of any protein-coding potential. A whole transcriptome (RNA-seq) study of Arabidopsis shoots under iron sufficient and deficient conditions was carried out to determine the genes that are iron-regulated in the shoots. We identified two previously unannotated transcripts on chromosome 1 that are significantly iron-regulated. We have called this iron-regulated lncRNA, CAN OF SPINACH (COS). cos mutants have altered iron levels in leaves and seeds. Despite the low iron levels in the leaves, cos mutants have higher chlorophyll levels than WT plants. Moreover, cos mutants have abnormal development during iron deficiency. Roots of cos mutants are longer than those of WT plants, when grown on iron deficient medium. In addition, cos mutant plants accumulate singlet oxygen during iron deficiency. The mechanism through which COS affects iron deficiency responses is unclear, but small regions of sequence similarity to several genes involved in iron deficiency responses occur in COS, and small RNAs from these regions have been detected. We hypothesize that COS is required for normal adaptation to iron deficiency conditions.
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Affiliation(s)
- Ahmet Bakirbas
- Plant Biology Graduate Program, Department of Biology, University of Massachusetts Amherst, Amherst, MA, United States
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, United States
| | - Elsbeth L. Walker
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, United States
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25
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Jan M, Liu Z, Rochaix JD, Sun X. Retrograde and anterograde signaling in the crosstalk between chloroplast and nucleus. FRONTIERS IN PLANT SCIENCE 2022; 13:980237. [PMID: 36119624 PMCID: PMC9478734 DOI: 10.3389/fpls.2022.980237] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/18/2022] [Indexed: 06/02/2023]
Abstract
The chloroplast is a complex cellular organelle that not only performs photosynthesis but also synthesizes amino acids, lipids, and phytohormones. Nuclear and chloroplast genetic activity are closely coordinated through signaling chains from the nucleus to chloroplast, referred to as anterograde signaling, and from chloroplast to the nucleus, named retrograde signaling. The chloroplast can act as an environmental sensor and communicates with other cell compartments during its biogenesis and in response to stress, notably with the nucleus through retrograde signaling to regulate nuclear gene expression in response to developmental cues and stresses that affect photosynthesis and growth. Although several components involved in the generation and transmission of plastid-derived retrograde signals and in the regulation of the responsive nuclear genes have been identified, the plastid retrograde signaling network is still poorly understood. Here, we review the current knowledge on multiple plastid retrograde signaling pathways, and on potential plastid signaling molecules. We also discuss the retrograde signaling-dependent regulation of nuclear gene expression within the frame of a multilayered network of transcription factors.
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Affiliation(s)
- Masood Jan
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Zhixin Liu
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Jean-David Rochaix
- Department of Molecular Biology and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Xuwu Sun
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
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Yuan J, Ma T, Ji S, Hedtke B, Grimm B, Lin R. Two chloroplast-localized MORF proteins act as chaperones to maintain tetrapyrrole biosynthesis. THE NEW PHYTOLOGIST 2022; 235:1868-1883. [PMID: 35615903 DOI: 10.1111/nph.18273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
Tetrapyrroles have essential functions as pigments and cofactors during plant growth and development, and the tetrapyrrole biosynthesis pathway is tightly controlled. Multiple organellar RNA editing factors (MORFs) are required for editing of a wide variety of RNA sites in chloroplasts and mitochondria, but their biochemical properties remain elusive. Here, we uncovered the roles of chloroplast-localized MORF2 and MORF9 in modulating tetrapyrrole biosynthesis and embryogenesis in Arabidopsis thaliana. The lack or reduced transcripts of MORF2 or MORF9 significantly affected biosynthesis of the tetrapyrrole precursor 5-aminolevulinic acid and accumulation of Chl and other tetrapyrrole intermediates. MORF2 directly interacts with multiple tetrapyrrole biosynthesis enzymes and regulators, including NADPH:PROTOCHLOROPHYLLIDE OXIDOREDUCTASE B (PORB) and GENOMES UNCOUPLED4 (GUN4). Strikingly, MORF2 and MORF9 display holdase chaperone activity, alleviate the aggregation of PORB in vitro, and are essential for POR accumulation in vivo. Moreover, both MORF2 and MORF9 significantly stimulate magnesium chelatase activity. Our findings reveal a previously unknown biochemical property of MORF proteins as chaperones and point to a new layer of post-translational control of the tightly regulated tetrapyrrole biosynthesis in plants.
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Affiliation(s)
- Jiarui Yuan
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tingting Ma
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Shuiling Ji
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, D-10099, Germany
| | - Boris Hedtke
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, D-10099, Germany
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, D-10099, Germany
| | - Rongcheng Lin
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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Zhang W, Deng R, Shi W, Li Z, Larkin RM, Fan Q, Duanmu D. Heme oxygenase-independent bilin biosynthesis revealed by a hmox1 suppressor screening in Chlamydomonas reinhardtii. Front Microbiol 2022; 13:956554. [PMID: 36003942 PMCID: PMC9393634 DOI: 10.3389/fmicb.2022.956554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Bilins are open-chain tetrapyrroles synthesized in phototrophs by successive enzymic reactions catalyzed by heme oxygenases (HMOXs/HOs) and ferredoxin-dependent biliverdin reductases (FDBRs) that typically serve as chromophore cofactors for phytochromes and phycobiliproteins. Chlamydomonas reinhardtii lacks both phycobiliproteins and phytochromes. Nonetheless, the activity and stability of photosystem I (PSI) and the catalytic subunit of magnesium chelatase (MgCh) named CHLH1 are significantly reduced and phototropic growth is significantly attenuated in a hmox1 mutant that is deficient in bilin biosynthesis. Consistent with these findings, previous studies on hmox1 uncovered an essential role for bilins in chloroplast retrograde signaling, maintenance of a functional photosynthetic apparatus, and the direct regulation of chlorophyll biosynthesis. In this study, we generated and screened a collection of insertional mutants in a hmox1 genetic background for suppressor mutants with phototropic growth restored to rates observed in wild-type 4A+ C. reinhardtii cells. Here, we characterized a suppressor of hmox1 named ho1su1 with phototrophic growth rates and levels of CHLH1 and PSI proteins similar to 4A+. Tetrad analysis indicated that a plasmid insertion co-segregated with the suppressor phenotype of ho1su1. Results from TAIL-PCR and plasmid rescue experiments demonstrated that the plasmid insertion was located in exon 1 of the HMOX1 locus. Heterologous expression of the bilin-binding reporter Nostoc punctiforme NpF2164g5 in the chloroplast of ho1su1 indicated that bilin accumulated in the chloroplast of ho1su1 despite the absence of the HMOX1 protein. Collectively, our study reveals the presence of an alternative bilin biosynthetic pathway independent of HMOX1 in the chloroplasts of Chlamydomonas cells.
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Affiliation(s)
- Weiqing Zhang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
| | - Rui Deng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
| | - Weida Shi
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
| | - Zheng Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
| | - Robert M. Larkin
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, China
| | - Qiuling Fan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
| | - Deqiang Duanmu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, China
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- *Correspondence: Deqiang Duanmu,
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Wang X, Li Q, Zhang Y, Pan M, Wang R, Sun Y, An L, Liu X, Yu F, Qi Y. VAR2/AtFtsH2 and EVR2/BCM1/CBD1 synergistically regulate the accumulation of PSII reaction centre D1 protein during de-etiolation in Arabidopsis. PLANT, CELL & ENVIRONMENT 2022; 45:2395-2409. [PMID: 35610189 DOI: 10.1111/pce.14368] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Thylakoid FtsH complex participates in PSII repair cycle during high light-induced photoinhibition. The Arabidopsis yellow variegated2 (var2) mutants are defective in the VAR2/AtFtsH2 subunit of thylakoid FtsH complex. Taking advantage of the var2 leaf variegation phenotype, dissections of genetic enhancer loci have yielded novel paradigms in understanding functions of thylakoid FtsH complex. Here, we report the isolation of a new var2 enhancer, enhancer of variegation2-1 (evr2-1). We confirmed that EVR2 encodes a chloroplast protein that was known as BALANCE OF CHLOROPHYLL METABOLISM 1 (BCM1), or CHLOROPHYLL BIOSYNTHETIC DEFECT 1 (CBD1). We showed that EVR2/BCM1/CBD1 was involved in the oligomerization of photosystem I complexes. Genetic assays indicated that general defects in chlorophyll biosynthesis and the accumulation of photosynthetic complexes do not necessarily enhance var2 leaf variegation. In addition, we found that VAR2/AtFtsH2 is required for the accumulation of photosynthetic proteins during de-etiolation. Moreover, we identified PSII core proteins D1 and PsbC as potential EVR2-associated proteins using Co-IP/MS. Furthermore, the accumulation of D1 protein was greatly compromised in the var2-5 evr2-1 double mutant during de-etiolation. Together, our findings reveal a functional link between VAR2/AtFtsH2 and EVR2/BCM1/CBD1 in regulating chloroplast development and the accumulation of PSII reaction centre D1 protein during de-etiolation.
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Affiliation(s)
- Xiaomin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Qinglong Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yalin Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Mi Pan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Ruijuan Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yifan Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Lijun An
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
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Yamatani H, Ito T, Nishimura K, Yamada T, Sakamoto W, Kusaba M. Genetic analysis of chlorophyll synthesis and degradation regulated by BALANCE of CHLOROPHYLL METABOLISM. PLANT PHYSIOLOGY 2022; 189:419-432. [PMID: 35348770 PMCID: PMC9070834 DOI: 10.1093/plphys/kiac059] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 01/24/2022] [Indexed: 05/05/2023]
Abstract
Chlorophyll (Chl) serves a number of essential functions, capturing and converting light energy as a component of photosystem supercomplexes. Chl degradation during leaf senescence is also required for adequate degeneration of chloroplasts and salvaging of nutrients from senescent leaves. In this study, we performed genetic analysis to determine the functions of BALANCE of CHLOROPHYLL METABOLISM1 (BCM1) and BCM2, which control Chl levels by regulating synthesis and degradation, and STAY-GREEN (SGR)1 (also known as NON-YELLOWING1 [NYE1]) and SGR2, which encode Mg-dechelatase and catalyze Chl a degradation in Arabidopsis (Arabidopsis thaliana). Analysis of bcm1 bcm2 revealed that both BCM1 and BCM2 are involved in the regulation of Chl levels in presenescent leaves and Chl degradation in senescing leaves. Analysis of bcm1 bcm2 nye1 nye2 suggested that BCMs repress Chl-degrading activity in both presenescent and senescing leaves by regulating SGR activity. Furthermore, transactivation analysis and chromatin immunoprecipitation (ChIP) assay revealed that GOLDEN2-LIKE1 (GLK1), a central transcription factor regulating the expression of genes encoding photosystem-related proteins, such as light-harvesting Chl a/b-binding proteins (LHCPs), directly regulates the transcription of BCM1. LHCPs are stabilized by Chl binding, suggesting that GLKs control the amount of LHCP through transcriptional and post-translational regulation via BCM-mediated Chl-level regulation. Meanwhile, we generated a mutant of the BCM ortholog in lettuce (Lactuca sativa) by genome editing and found that it showed an early yellowing phenotype, but only a slight reduction in Chl in presenescent leaves. Thus, this study revealed a conserved but slightly diversified regulation of Chl and LHCP levels via the GLK-BCM pathway in eudicots.
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Affiliation(s)
| | - Takeshi Ito
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
| | | | - Tetsuya Yamada
- Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan
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30
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Liao HS, Chung YH, Hsieh MH. Glutamate: A multifunctional amino acid in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 318:111238. [PMID: 35351313 DOI: 10.1016/j.plantsci.2022.111238] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/15/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
Glutamate (Glu) is a versatile metabolite and a signaling molecule in plants. Glu biosynthesis is associated with the primary nitrogen assimilation pathway. The conversion between Glu and 2-oxoglutarate connects Glu metabolism to the tricarboxylic acid cycle, carbon metabolism, and energy production. Glu is the predominant amino donor for transamination reactions in the cell. In addition to protein synthesis, Glu is a building block for tetrapyrroles, glutathione, and folate. Glu is the precursor of γ-aminobutyric acid that plays an important role in balancing carbon/nitrogen metabolism and various cellular processes. Glu can conjugate to the major auxin indole 3-acetic acid (IAA), and IAA-Glu is destined for oxidative degradation. Glu also conjugates with isochorismate for the production of salicylic acid. Accumulating evidence indicates that Glu functions as a signaling molecule to regulate plant growth, development, and defense responses. The ligand-gated Glu receptor-like proteins (GLRs) mediate some of these responses. However, many of the Glu signaling events are GLR-independent. The receptor perceiving extracellular Glu as a danger signal is still unknown. In addition to GLRs, Glu may act on receptor-like kinases or receptor-like proteins to trigger immune responses. Glu metabolism and Glu signaling may entwine to regulate growth, development, and defense responses in plants.
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Affiliation(s)
- Hong-Sheng Liao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Yi-Hsin Chung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Ming-Hsiun Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; Department of Life Sciences, National Central University, Taoyuan 32001, Taiwan.
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31
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Simkin AJ, Kapoor L, Doss CGP, Hofmann TA, Lawson T, Ramamoorthy S. The role of photosynthesis related pigments in light harvesting, photoprotection and enhancement of photosynthetic yield in planta. PHOTOSYNTHESIS RESEARCH 2022; 152:23-42. [PMID: 35064531 DOI: 10.1007/s11120-021-00892-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 12/13/2021] [Indexed: 05/06/2023]
Abstract
Photosynthetic pigments are an integral and vital part of all photosynthetic machinery and are present in different types and abundances throughout the photosynthetic apparatus. Chlorophyll, carotenoids and phycobilins are the prime photosynthetic pigments which facilitate efficient light absorption in plants, algae, and cyanobacteria. The chlorophyll family plays a vital role in light harvesting by absorbing light at different wavelengths and allowing photosynthetic organisms to adapt to different environments, either in the long-term or during transient changes in light. Carotenoids play diverse roles in photosynthesis, including light capture and as crucial antioxidants to reduce photodamage and photoinhibition. In the marine habitat, phycobilins capture a wide spectrum of light and have allowed cyanobacteria and red algae to colonise deep waters where other frequencies of light are attenuated by the water column. In this review, we discuss the potential strategies that photosynthetic pigments provide, coupled with development of molecular biological techniques, to improve crop yields through enhanced light harvesting, increased photoprotection and improved photosynthetic efficiency.
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Affiliation(s)
- Andrew J Simkin
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, United Kingdom
| | - Leepica Kapoor
- School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - C George Priya Doss
- School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - Tanja A Hofmann
- OSFC, Scrivener Drive, Pinewood, Ipswich, IP8 3SU, United Kingdom
| | - Tracy Lawson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom
| | - Siva Ramamoorthy
- School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India.
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32
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Fölsche V, Großmann C, Richter AS. Impact of Porphyrin Binding to GENOMES UNCOUPLED 4 on Tetrapyrrole Biosynthesis in planta. FRONTIERS IN PLANT SCIENCE 2022; 13:850504. [PMID: 35371166 PMCID: PMC8967248 DOI: 10.3389/fpls.2022.850504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
Plant tetrapyrrole biosynthesis (TPS) provides the indispensable chlorophyll (Chl) and heme molecules in photosynthetic organisms. Post-translational mechanisms control the enzymes to ensure a balanced flow of intermediates in the pathway and synthesis of appropriate amounts of both endproducts. One of the critical regulators of TPS is GENOMES UNCOUPLED 4 (GUN4). GUN4 interacts with magnesium chelatase (MgCh), and its binding of the catalytic substrate and product of the MgCh reaction stimulates the insertion of Mg2+ into protoporphyrin IX. Despite numerous in vitro studies, knowledge about the in vivo function of the GUN4:porphyrin interaction for the whole TPS pathway, particularly in plants, is still limited. To address this, we focused on two highly conserved amino acids crucial for porphyrin-binding to GUN4 and analyzed GUN4-F191A, R211A, and R211E substitution mutants in vitro and in vivo. Our analysis confirmed the importance of these amino acids for porphyrin-binding and the stimulation of plant MgCh by GUN4 in vitro. Expression of porphyrin-binding deficient F191A, R211A, and R211E in the Arabidopsis gun4-2 knockout mutant background revealed that, unlike in cyanobacteria and green algae, GUN4:porphyrin interactions did not affect the stability of GUN4 or other Arabidopsis TPS pathway enzymes in vivo. In addition, although they shared diminished porphyrin-binding and MgCh activation in vitro, expression of the different GUN4 mutants in gun4-2 had divergent effects on the TPS and the accumulation of Chl and Chl-binding proteins. For instance, expression of R211E, but not R211A, induced a substantial decrease of ALA synthesis rate, lower TPS intermediate and Chl level, and strongly impaired accumulation of photosynthetic complexes compared to wild-type plants. Furthermore, the presence of R211E led to significant growth retardation and paler leaves compared to GUN4 knockdown mutants, indicating that the exchange of R211 to glutamate compromised TPS and Chl accumulation more substantially than the almost complete lack of GUN4. Extensive in vivo analysis of GUN4 point mutants suggested that F191 and R211 might also play a role beyond porphyrin-binding.
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Affiliation(s)
- Vincent Fölsche
- Physiology of Plant Cell Organelles, Humboldt-Universität Berlin, Berlin, Germany
- Department of Plant Physiology, Humboldt-Universität Berlin, Berlin, Germany
| | - Christopher Großmann
- Physiology of Plant Cell Organelles, Humboldt-Universität Berlin, Berlin, Germany
| | - Andreas S. Richter
- Physiology of Plant Cell Organelles, Humboldt-Universität Berlin, Berlin, Germany
- Department of Plant Physiology, Humboldt-Universität Berlin, Berlin, Germany
- Physiology of Plant Metabolism, University of Rostock, Rostock, Germany
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33
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Jedynak P, Trzebuniak KF, Chowaniec M, Zgłobicki P, Banaś AK, Mysliwa-Kurdziel B. Dynamics of Etiolation Monitored by Seedling Morphology, Carotenoid Composition, Antioxidant Level, and Photoactivity of Protochlorophyllide in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 12:772727. [PMID: 35265091 PMCID: PMC8900029 DOI: 10.3389/fpls.2021.772727] [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: 09/08/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Although etiolated Arabidopsis thaliana seedlings are widely used as a model to study the de-etiolation process, the etiolation itself at the molecular level still needs elucidation. Here, we monitored the etiolation dynamics for wild type A. thaliana seedlings and lutein-deficient (lut2) mutant between 2 and 12 days of their growth in the absence of light. We analyzed the shape of the apex, the growth rate, the carotenoids and protochlorophyllide (Pchlide) accumulation, and the light-dependent protochlorophyllide oxidoreductase (LPOR) transcripts. Differences concerning the apical hook curvature and cotyledon opening among seedlings of the same age were observed, mostly after day 6 of the culture. We categorized the observed apex shapes and presented quantitatively how distribution among the categories changed during 12 days of seedling growth. The Pchlide654/Pchlide633 ratio, corresponding to the amount of the photoactive Pchlide, was the highest in the youngest seedlings, and decreased with their age. LPORA, LPORB, and LPORC transcripts were detected in etiolated seedlings, and their content decreased during seedling growth. Expression of SAG12 or SAG13 senescence markers, depletion in antioxidants, and excess ion leakage were not observed during the etiolation. Lack of lutein in the lut2 mutant resulted in slow Pchlide accumulation and affected other xanthophyll composition.
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Affiliation(s)
- Pawel Jedynak
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Kamil Filip Trzebuniak
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Magdalena Chowaniec
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Piotr Zgłobicki
- Department of Plant Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Agnieszka Katarzyna Banaś
- Department of Plant Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Beata Mysliwa-Kurdziel
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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34
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Feng Y, Zhao Y, Li Y, Zhou J, Li Y, Shi H. Physiological and transcriptome analysis reveals the differences in nitrate content between lamina and midrib of flue-cured tobacco. Sci Rep 2022; 12:2932. [PMID: 35190651 PMCID: PMC8861034 DOI: 10.1038/s41598-022-07011-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 02/07/2022] [Indexed: 11/09/2022] Open
Abstract
Nitrate is an important precursor of tobacco-specific nitrosamines (TSNAs) and a remarkable difference in nitrate accumulation between lamina and midrib of flue-cured tobacco has long been observed. However, the physiological and molecular mechanisms underpinning this difference remain poorly understood. In this study, physiological and genetic factors impacting nitrate accumulation were identified in pot experiments using flue-cured tobacco K326 with contrasting nitrate content between lamina and midrib. The results showed that three times higher NO3-N content was observed in midrib than that in the lamina, along with lower pigment, NH4-N content, nitrate reductase activity (NRA), sucrose synthetase activity (SSA), and glutamine synthetase activity (GSA) in midrib. Transcriptome analysis revealed that expression of genes involved in porphyrin and chlorophyll metabolism, carotenoid biosynthesis, photosynthesis-antenna proteins, photosynthesis, carbon fixation in photosynthetic organisms, starch and sucrose metabolism, nitrogen metabolism, and biosynthesis of amino acids were significantly lower in midrib than in lamina. qRT-PCR results showed that the expression level of nitrate transporter genes LOC107782967, LOC107806749, LOC107775674, LOC107829632, LOC107799198, LOC107768465 decreased by 2.74, 1.81, 49.5, 3.5, 2.64 and 2.96-folds while LOC107789301 increased by 8.23-folds in midrib but not in lamina. Reduced chlorophyll content might result in low carbohydrate formation which is the source of energy and carbon skeleton supply, then the low capacity of nitrogen reduction, assimilation and transportation, and the poor ability of nitrate reallocation but the high capacity of accumulation might lead to nitrate accumulation in midrib. The results laid the foundation for reducing nitrate content and TSNA formation in tobacco midribs and their products.
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Affiliation(s)
- Yuqing Feng
- National Tobacco Cultivation & Physiology & Biochemistry Research Center, Tobacco Harm Reduction Research Center of China Tobacco, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yuanyuan Zhao
- National Tobacco Cultivation & Physiology & Biochemistry Research Center, Tobacco Harm Reduction Research Center of China Tobacco, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yafei Li
- National Tobacco Cultivation & Physiology & Biochemistry Research Center, Tobacco Harm Reduction Research Center of China Tobacco, Henan Agricultural University, Zhengzhou, 450002, China
| | - Jun Zhou
- Beijing Cigarette Factory, Shanghai Tobacco Group Co., Ltd., Beijing, 100024, China
| | - Yujing Li
- National Tobacco Cultivation & Physiology & Biochemistry Research Center, Tobacco Harm Reduction Research Center of China Tobacco, Henan Agricultural University, Zhengzhou, 450002, China
| | - Hongzhi Shi
- National Tobacco Cultivation & Physiology & Biochemistry Research Center, Tobacco Harm Reduction Research Center of China Tobacco, Henan Agricultural University, Zhengzhou, 450002, China.
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35
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Li YM, You JL, Nie WF, Sun MH, Xie ZS. Transcription Profiles Reveal Age-Dependent Variations of Photosynthetic Properties and Sugar Metabolism in Grape Leaves (Vitis vinifera L.). Int J Mol Sci 2022; 23:ijms23042243. [PMID: 35216359 PMCID: PMC8876361 DOI: 10.3390/ijms23042243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/10/2022] [Accepted: 02/12/2022] [Indexed: 12/10/2022] Open
Abstract
Leaves, considered as the ‘source’ organs, depend on the development stages because of the age-dependent photosynthesis and assimilation of leaves. However, the molecular mechanisms of age-dependent limitations on the function of leaves are seldom reported. In the present study, the photosynthesis-related characteristics and photoassimilates were investigated in grape leaves at six different age groups (Ll to L6) at micro-morphological, biochemical, and molecular levels. These results showed lower expression levels of genes associated with stomatal development, and chl biosynthesis resulted in fewer stomata and lowered chlorophyll a/b contents in L1 when compared to L3 and L5. The DEGs between L5 and L3/L1 were largely distributed at stomatal movement, carbon fixation, and sucrose and starch metabolism pathways, such as STOMATAL ANION CHANNEL PROTEIN 1 (SLAC1), FRUCTOSE-1,6-BISPHOSPHATE ALDOLASE (FBA1), SUCROSE-PHOSPHATE SYNTHASE (SPP1), and SUCROSE-PHOSPHATE PHOSPHATASE (SPS2, 4). These genes could be major candidate genes leading to increased photosynthesis capacity and sugar content in L5. The accumulation of starch grains in the chloroplast and palisade tissue of L5 and higher transcription levels of genes related to starch biosynthesis in L5 further supported the high ability of L5 to produce photoassimilates. Hence, our results provide insights for understanding different photosynthetic functions in age-dependent leaves in grape plants at the molecular level.
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Fisher KE, Krishnamoorthy P, Joens MS, Chory J, Fitzpatrick JAJ, Woodson JD. Singlet Oxygen Leads to Structural Changes to Chloroplasts during their Degradation in the Arabidopsis thaliana plastid ferrochelatase two Mutant. PLANT & CELL PHYSIOLOGY 2022; 63:248-264. [PMID: 34850209 DOI: 10.1093/pcp/pcab167] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/01/2021] [Accepted: 11/22/2021] [Indexed: 06/13/2023]
Abstract
During stress, chloroplasts produce large amounts of reactive oxygen species (ROS). Chloroplasts also contain many nutrients, including 80% of a leaf's nitrogen supply. Therefore, to protect cells from photo-oxidative damage and to redistribute nutrients to sink tissues, chloroplasts are prime targets for degradation. Multiple chloroplast degradation pathways are induced by photo-oxidative stress or nutrient starvation, but the mechanisms by which damaged or senescing chloroplasts are identified, transported to the central vacuole and degraded are poorly defined. Here, we investigated the structures involved with degrading chloroplasts induced by the ROS singlet oxygen (1O2) in the Arabidopsis thaliana plastid ferrochelatase two (fc2) mutant. Under mild 1O2 stress, most fc2 chloroplasts appeared normal, but had reduced starch content. A subset of chloroplasts was degrading, and some protruded into the central vacuole via 'blebbing' structures. A 3D electron microscopy analysis demonstrated that up to 35% of degrading chloroplasts contained such structures. While the location of a chloroplast within a cell did not affect the likelihood of its degradation, chloroplasts in spongy mesophyll cells were degraded at a higher rate than those in palisade mesophyll cells. To determine if degrading chloroplasts have unique structural characteristics, allowing them to be distinguished from healthy chloroplasts, we analyzed fc2 seedlings grown under different levels of photo-oxidative stress. A correlation was observed among chloroplast swelling, 1O2 signaling and the state of degradation. Finally, plastoglobule (PG) enzymes involved in chloroplast disassembly were upregulated while PGs increased their association with the thylakoid grana, implicating an interaction between 1O2-induced chloroplast degradation and senescence pathways.
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Affiliation(s)
- Karen E Fisher
- The School of Plant Sciences, University of Arizona, 1140 E South Campus Dr., Tucson, AZ 85721, USA
| | - Praveen Krishnamoorthy
- Washington University Center for Cellular Imaging, Washington University School of Medicine, 660 W. Euclid Avenue, St. Louis, MO 63110, USA
| | | | - Joanne Chory
- Plant Biology Laboratory and the Howard Hughes Medical Institute, The Salk Institute, 10010 N Torrey Pines Rd., La Jolla, CA 92037, USA
| | - James A J Fitzpatrick
- Washington University Center for Cellular Imaging, Washington University School of Medicine, 660 W. Euclid Avenue, St. Louis, MO 63110, USA
- Departments of Cell Biology & Physiology and Neuroscience, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
- Department of Biomedical Engineering, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130, USA
| | - Jesse D Woodson
- The School of Plant Sciences, University of Arizona, 1140 E South Campus Dr., Tucson, AZ 85721, USA
- Washington University Center for Cellular Imaging, Washington University School of Medicine, 660 W. Euclid Avenue, St. Louis, MO 63110, USA
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iTRAQ-Based Quantitative Proteomics Analysis Reveals the Mechanism of Golden-Yellow Leaf Mutant in Hybrid Paper Mulberry. Int J Mol Sci 2021; 23:ijms23010127. [PMID: 35008552 PMCID: PMC8745438 DOI: 10.3390/ijms23010127] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 11/17/2022] Open
Abstract
Plant growth and development relies on the conversion of light energy into chemical energy, which takes place in the leaves. Chlorophyll mutant variations are important for studying certain physiological processes, including chlorophyll metabolism, chloroplast biogenesis, and photosynthesis. To uncover the mechanisms of the golden-yellow phenotype of the hybrid paper mulberry plant, this study used physiological, cytological, and iTRAQ-based proteomic analyses to compare the green and golden-yellow leaves of hybrid paper mulberry. Physiological results showed that the mutants of hybrid paper mulberry showed golden-yellow leaves, reduced chlorophyll, and carotenoid content, and increased flavonoid content compared with wild-type plants. Cytological observations revealed defective chloroplasts in the mesophyll cells of the mutants. Results demonstrated that 4766 proteins were identified from the hybrid paper mulberry leaves, of which 168 proteins displayed differential accumulations between the green and mutant leaves. The differentially accumulated proteins were primarily involved in chlorophyll synthesis, carotenoid metabolism, and photosynthesis. In addition, differentially accumulated proteins are associated with ribosome pathways and could enable plants to adapt to environmental conditions by regulating the proteome to reduce the impact of chlorophyll reduction on growth and survival. Altogether, this study provides a better understanding of the formation mechanism of the golden-yellow leaf phenotype by combining proteomic approaches.
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Cheong MS, Choe H, Jeong MS, Yoon YE, Jung HS, Lee YB. Different Inhibitory Effects of Erythromycin and Chlortetracycline on Early Growth of Brassica campestris Seedlings. Antibiotics (Basel) 2021; 10:antibiotics10101273. [PMID: 34680853 PMCID: PMC8532913 DOI: 10.3390/antibiotics10101273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/15/2021] [Accepted: 10/17/2021] [Indexed: 01/14/2023] Open
Abstract
Veterinary antibiotics, including erythromycin (Ery) and chlortetracycline (CTC), are often detected in agricultural land. Although these contaminants affect plant growth and development, their effects on crops remain elusive. In this study, the effects of Ery and CTC on plant growth were investigated and compared by analyzing transcript abundance in Brassica campestris seedlings. Treatment with Ery and/or CTC reduced chlorophyll content in leaves and photosynthetic efficiency. Examination of the chloroplast ultrastructure revealed the presence of abnormally shaped plastids in response to Ery and CTC treatments. The antibiotics produced similar phenotypes of lower accumulation of photosynthetic genes, including RBCL and LHCB1.1. Analysis of the transcript levels revealed that Ery and CTC differentially down-regulated genes involved in the tetrapyrrole biosynthetic pathway and primary root growth. In the presence of Ery and CTC, chloroplasts were undeveloped and photosynthesis efficiency was reduced. These results suggest that both Ery and CTC individually affect gene expression and influence plant physiological activity, independently of one another.
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Affiliation(s)
- Mi Sun Cheong
- Institute of Agriculture and Life Science (IALS), Gyeongsang National University, Jinju 52828, Korea;
| | - Hyeonji Choe
- Division of Applied Life Science (BK21 Four), Gyeongsang National University, Jinju 52828, Korea; (H.C.); (Y.-E.Y.)
| | - Myeong Seon Jeong
- Department of Biochemistry, Kangwon National University, Chuncheon 24341, Korea; (M.S.J.); (H.S.J.)
- Chuncheon Center, Korea Basic Science Institute (KBSI), Chuncheon 24341, Korea
| | - Young-Eun Yoon
- Division of Applied Life Science (BK21 Four), Gyeongsang National University, Jinju 52828, Korea; (H.C.); (Y.-E.Y.)
| | - Hyun Suk Jung
- Department of Biochemistry, Kangwon National University, Chuncheon 24341, Korea; (M.S.J.); (H.S.J.)
| | - Yong Bok Lee
- Institute of Agriculture and Life Science (IALS), Gyeongsang National University, Jinju 52828, Korea;
- Division of Applied Life Science (BK21 Four), Gyeongsang National University, Jinju 52828, Korea; (H.C.); (Y.-E.Y.)
- Correspondence: ; Tel.: +82-55-772-1967
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Ma L, Liu Z, Cheng Z, Gou J, Chen J, Yu W, Wang P. Identification and Application of BhAPRR2 Controlling Peel Colour in Wax Gourd ( Benincasa hispida). FRONTIERS IN PLANT SCIENCE 2021; 12:716772. [PMID: 34659288 PMCID: PMC8517133 DOI: 10.3389/fpls.2021.716772] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 08/26/2021] [Indexed: 05/24/2023]
Abstract
Peel color is an important factor affecting commodity quality in vegetables; however, the genes controlling this trait remain unclear in wax gourd. Here, we used two F2 genetic segregation populations to explore the inheritance patterns and to clone the genes associated with green and white skin in wax gourd. The F2 and BC1 trait segregation ratios were 3:1 and 1:1, respectively, and the trait was controlled by nuclear genes. Bulked segregant analysis of both F2 plants revealed peaks on Chr5 exceeding the confidence interval. Additionally, 6,244 F2 plants were used to compress the candidate interval into a region of 179 Kb; one candidate gene, Bch05G003950 (BhAPRR2), encoding two-component response regulator-like protein Arabidopsis pseudo-response regulator2 (APRR2), which is involved in the regulation of peel color, was present in this interval. Two bases (GA) present in the coding sequence of BhAPRR2 in green-skinned wax gourd were absent from white-skinned wax gourd. The latter contained a frameshift mutation, a premature stop codon, and lacked 335 residues required for the protein functional region. The chlorophyll content and BhAPRR2 expression were significantly higher in green-skinned than in white-skinned wax gourd. Thus, BhAPRR2 may regulate the peel color of wax gourd. This study provides a theoretical foundation for further studies of the mechanism of gene regulation for the fruit peel color of wax gourd.
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Affiliation(s)
- Lianlian Ma
- College of Agriculture, Guangxi University, Nanning, China
| | - Zhengguo Liu
- College of Agriculture, Guangxi University, Nanning, China
| | - Zhikui Cheng
- College of Agriculture, Guangxi University, Nanning, China
| | - Jiquan Gou
- College of Agriculture, Guangxi University, Nanning, China
| | - Jieying Chen
- College of Agriculture, Guangxi University, Nanning, China
| | - Wenjin Yu
- College of Agriculture, Guangxi University, Nanning, China
| | - Peng Wang
- College of Agriculture, Guangxi University, Nanning, China
- Institute of Vegetable Research, Guangxi Academy of Agricultural Sciences, Nanning, China
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Ji S, Siegel A, Shan SO, Grimm B, Wang P. Chloroplast SRP43 autonomously protects chlorophyll biosynthesis proteins against heat shock. NATURE PLANTS 2021; 7:1420-1432. [PMID: 34475529 PMCID: PMC8879858 DOI: 10.1038/s41477-021-00994-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 07/28/2021] [Indexed: 06/02/2023]
Abstract
The assembly of light-harvesting chlorophyll-binding proteins (LHCPs) is coordinated with chlorophyll biosynthesis during chloroplast development. The ATP-independent chaperone known as chloroplast signal recognition particle 43 (cpSRP43) mediates post-translational LHCP targeting to the thylakoid membrane and also participates in tetrapyrrole biosynthesis (TBS). How these distinct actions of cpSRP43 are controlled has remained unclear. Here, we demonstrate that cpSRP43 effectively protects several TBS proteins from heat-induced aggregation and enhances their stability during leaf greening and heat shock. While the substrate-binding domain of cpSRP43 is sufficient for chaperoning LHCPs, the stabilization of TBS clients requires the chromodomain 2 of the protein. Strikingly, cpSRP54-which activates cpSRP43's LHCP-targeted function-inhibits the chaperone activity of cpSRP43 towards TBS proteins. High temperature weakens the interaction of cpSRP54 with cpSRP43, thus freeing cpSRP43 to interact with and protect the integrity of TBS proteins. Our data indicate that the temperature sensitivity of the cpSRP43-cpSRP54 complex enables cpSRP43 to serve as an autonomous chaperone for the thermoprotection of TBS proteins.
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Affiliation(s)
- Shuiling Ji
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Alex Siegel
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Shu-Ou Shan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, Germany.
| | - Peng Wang
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Berlin, Germany.
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41
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Yuan L, Zhang L, Wu Y, Zheng Y, Nie L, Zhang S, Lan T, Zhao Y, Zhu S, Hou J, Chen G, Tang X, Wang C. Comparative transcriptome analysis reveals that chlorophyll metabolism contributes to leaf color changes in wucai (Brassica campestris L.) in response to cold. BMC PLANT BIOLOGY 2021; 21:438. [PMID: 34583634 PMCID: PMC8477495 DOI: 10.1186/s12870-021-03218-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 09/20/2021] [Indexed: 05/25/2023]
Abstract
BACKGROUND Chlorophyll (Chl) is a vital photosynthetic pigment involved in capturing light energy and energy conversion. In this study, the color conversion of inner-leaves from green to yellow in the new wucai (Brassica campestris L.) cultivar W7-2 was detected under low temperature. The W7-2 displayed a normal green leaf phenotype at the seedling stage, but the inner leaves gradually turned yellow when the temperature was decreased to 10 °C/2 °C (day/night), This study facilitates us to understand the physiological and molecular mechanisms underlying leaf color changes in response to low temperature. RESULTS A comparative leaf transcriptome analysis of W7-2 under low temperature treatment was performed on three stages (before, during and after leaf color change) with leaves that did not change color under normal temperature at the same period as a control. A total of 67,826 differentially expressed genes (DEGs) were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analysis revealed that the DEGs were mainly enriched in porphyrin and Chl metabolism, carotenoids metabolism, photosynthesis, and circadian rhythm. In the porphyrin and chlorophyll metabolic pathways, the expression of several genes was reduced [i.e. magnesium chelatase subunit H (CHLH)] under low temperature. Almost all genes [i.e. phytoene synthase (PSY)] in the carotenoids (Car) biosynthesis pathway were downregulated under low temperature. The genes associated with photosynthesis [i.e. photosystem II oxygen-evolving enhancer protein 1 (PsbO)] were also downregulated under LT. Our study also showed that elongated hypocotyl5 (HY5), which participates in circadian rhythm, and the metabolism of Chl and Car, is responsible for the regulation of leaf color change and cold tolerance in W7-2. CONCLUSIONS The color of inner-leaves was changed from green to yellow under low temperature in temperature-sensitive mutant W7-2. Physiological, biochemical and transcriptomic studies showed that HY5 transcription factor and the downstream genes such as CHLH and PSY, which regulate the accumulation of different pigments, are required for the modulation of leaf color change in wucai under low temperature.
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Affiliation(s)
- Lingyun Yuan
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
| | - Liting Zhang
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Ying Wu
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Yushan Zheng
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Libing Nie
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Shengnan Zhang
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Tian Lan
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Yang Zhao
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
| | - Shidong Zhu
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
| | - Jinfeng Hou
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
| | - Guohu Chen
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
| | - Xiaoyan Tang
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
| | - Chenggang Wang
- College of Horticulture, Vegetable Genetics and Breeding Laboratory, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 Anhui China
- Provincial Engineering Laboratory for Horticultural Crop Breeding of Anhui, 130 West of Changjiang Road, Hefei, 230036 Anhui China
- Wanjiang Vegetable Industrial Technology Institute, Maanshan, 238200 Anhui China
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42
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Woodson JD. All in the timing: epigenetic control of greening. THE NEW PHYTOLOGIST 2021; 231:907-909. [PMID: 34125971 DOI: 10.1111/nph.17454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- Jesse D Woodson
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721-0036, USA
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Alamdari K, Fisher KE, Tano DW, Rai S, Palos K, Nelson ADL, Woodson JD. Chloroplast quality control pathways are dependent on plastid DNA synthesis and nucleotides provided by cytidine triphosphate synthase two. THE NEW PHYTOLOGIST 2021; 231:1431-1448. [PMID: 33993494 DOI: 10.1111/nph.17467] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/04/2021] [Indexed: 06/12/2023]
Abstract
Reactive oxygen species (ROS) produced in chloroplasts cause oxidative damage, but also signal to initiate chloroplast quality control pathways, cell death, and gene expression. The Arabidopsis thaliana plastid ferrochelatase two (fc2) mutant produces the ROS singlet oxygen in chloroplasts that activates such signaling pathways, but the mechanisms are largely unknown. Here we characterize one fc2 suppressor mutation and map it to CYTIDINE TRIPHOSPHATE SYNTHASE TWO (CTPS2), which encodes one of five enzymes in Arabidopsis necessary for de novo cytoplasmic CTP (and dCTP) synthesis. The ctps2 mutation reduces chloroplast transcripts and DNA content without similarly affecting mitochondria. Chloroplast nucleic acid content and singlet oxygen signaling are restored by exogenous feeding of the dCTP precursor deoxycytidine, suggesting ctps2 blocks signaling by limiting nucleotides for chloroplast genome maintenance. An investigation of CTPS orthologs in Brassicaceae showed CTPS2 is a member of an ancient lineage distinct from CTPS3. Complementation studies confirmed this analysis; CTPS3 was unable to compensate for CTPS2 function in providing nucleotides for chloroplast DNA and signaling. Our studies link cytoplasmic nucleotide metabolism with chloroplast quality control pathways. Such a connection is achieved by a conserved clade of CTPS enzymes that provide nucleotides for chloroplast function, thereby allowing stress signaling to occur.
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Affiliation(s)
- Kamran Alamdari
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | - Karen E Fisher
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | - David W Tano
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | - Snigdha Rai
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | - Kyle Palos
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | | | - Jesse D Woodson
- The School of Plant Sciences, University of Arizona, Tucson, AZ, 85721, USA
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Hu B, Mithöfer A, Reichelt M, Eggert K, Peters FS, Ma M, Schumacher J, Kreuzwieser J, von Wirén N, Rennenberg H. Systemic reprogramming of phytohormone profiles and metabolic traits by virulent Diplodia infection in its pine (Pinus sylvestris L.) host. PLANT, CELL & ENVIRONMENT 2021; 44:2744-2764. [PMID: 33822379 DOI: 10.1111/pce.14061] [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: 02/24/2021] [Revised: 03/31/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
The widespread ascomycetous fungus Diplodia pinea is a latent, necrotrophic pathogen in Pinus species causing severe damages and world-wide economic losses. However, the interactions between pine hosts and virulent D. pinea are largely not understood. In the present study, systemic defence responses were investigated in non-inoculated, asymptomatic needles and roots of D. pinea infected saplings of two P. sylvestris provenances under controlled greenhouse conditions. Here, we show that D. pinea infection induced a multitude of systemic responses of the phytohormone profiles and metabolic traits. Shared systemic responses of both pine provenances in needles and roots included increased abscisic acid and jasmonic acid levels. Exclusively in the roots of both provenances, enhanced salicylic acid and reduced indole-3-acetic acid levels, structural biomass, and elevated activities of anti-oxidative enzymes were observed. Despite these similarities, the two pine provenances investigated different significantly in the systemic responses of both, phytohormone profiles and metabolic traits in needles and roots. However, the different systemic responses did not prevent subsequent destruction of non-inoculated needles, but rather prevented damage to the roots. Our results provide a detailed view on systemic defence mechanisms of pine hosts that are of particular significance for the selection of provenances with improved defence capacity.
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Affiliation(s)
- Bin Hu
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University No. 2, Chongqing, China
- Institute of Forest Sciences, Chair of Tree Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Axel Mithöfer
- Research Group Plant Defense Physiology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Kai Eggert
- Molecular Plant Nutrition, Leibniz-Institute for Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Franziska S Peters
- Institute of Forest Sciences, Chair of Tree Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
- Department of Forest Protection, FVA Forest Research Institute of Baden-Württemberg (FVA-BW), Freiburg, Germany
| | - Ming Ma
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University No. 2, Chongqing, China
| | - Jörg Schumacher
- Department of Forest Protection, FVA Forest Research Institute of Baden-Württemberg (FVA-BW), Freiburg, Germany
- Department of Forest Health and Risk Management, University for Sustainable Development (HNE Eberswalde), Eberswalde, Germany
| | - Jürgen Kreuzwieser
- Institute of Forest Sciences, Chair of Tree Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Nicolaus von Wirén
- Molecular Plant Nutrition, Leibniz-Institute for Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Heinz Rennenberg
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University No. 2, Chongqing, China
- Institute of Forest Sciences, Chair of Tree Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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Hu L, Liu P, Jin Z, Sun J, Weng Y, Chen P, Du S, Wei A, Li Y. A mutation in CsHY2 encoding a phytochromobilin (PΦB) synthase leads to an elongated hypocotyl 1(elh1) phenotype in cucumber (Cucumis sativus L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:2639-2652. [PMID: 34091695 DOI: 10.1007/s00122-021-03849-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/29/2021] [Indexed: 06/12/2023]
Abstract
The elongated hypocotyl1 (elh1) mutant in cucumber is due to a mutation in CsHY2, which is a homolog of the Arabidopsis HY2 encoding the phytochromobilin (PΦB) synthase for phytochrome biosynthesis Hypocotyl length is a critical determinant in establishing high quality seedlings for successful cucumber production, but knowledge on the molecular regulation of hypocotyl growth in cucumber is very limited. Here, we reported identification and characterization of a cucumber elongated hypocotyl 1 (elh1) mutant. We found that the longer hypocotyl in elh1 was due to longitudinal growth of hypocotyl cells. With fine mapping, the elh1 locus was delimited to a 20.9-kb region containing three annotated genes; only one polymorphism was identified in this region between two parental lines, which was a non-synonymous SNP (G28153633A) in the third exon of CsHY2 (CsGy1G030000) that encodes a phytochromobilin (PΦB) synthase. Uniqueness of the mutant allele at CsHY2 was verified in natural cucumber populations. Ectopic expression of CsHY2 in Arabidopsis hy2-1 long-hypocotyl mutant led to reduced hypocotyl length. The PΦB protein was targeted to the chloroplast. The expression levels of CsHY2 and five phytochrome genes CsPHYA1, CsPHYA2, CsPHYB, CsPHYC and CsPHYE were all significantly down-regulated while several cell elongation related genes were up-regulated in elh1 mutant compared to wild-type cucumber, which are correlated with dynamic hypocotyl elongation in the mutant. RNA-seq analysis in the WT and mutant revealed differentially expressed genes involved in porphyrin and chlorophyll metabolisms, cell elongation and plant hormone signal transduction pathways. This is the first report to characterize and clone the CsHY2 gene in cucumber. This work reveals the important of CsHY2 in regulating hypocotyl length and extends our understanding of the roles of CsHY2 in cucumber.
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Affiliation(s)
- Liangliang Hu
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Peng Liu
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Zhuoshuai Jin
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jing Sun
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yiqun Weng
- Horticulture Department, USDA-ARS Vegetable Crops Research Unit, University of Wisconsin, Madison, WI, 53706, USA
| | - Peng Chen
- College of Life Science, Northwest A & F University, Yangling, 712100, Shaanxi,, China
| | - Shengli Du
- Tianjin Vegetable Research Center, Tianjin, 300192, China
- National Key Laboratory of Vegetable Germplasm Innovation, Tianjin, 300192, China
| | - Aimin Wei
- Tianjin Vegetable Research Center, Tianjin, 300192, China.
- National Key Laboratory of Vegetable Germplasm Innovation, Tianjin, 300192, China.
| | - Yuhong Li
- College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Jiang A, Guo Z, Pan J, Yang Y, Zhuang Y, Zuo D, Hao C, Gao Z, Xin P, Chu J, Zhong S, Li L. The PIF1-miR408-PLANTACYANIN repression cascade regulates light-dependent seed germination. THE PLANT CELL 2021; 33:1506-1529. [PMID: 33616669 PMCID: PMC8254493 DOI: 10.1093/plcell/koab060] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 02/11/2021] [Indexed: 05/15/2023]
Abstract
Light-dependent seed germination is a vital process for many seed plants. A decisive event in light-induced germination is degradation of the central repressor PHYTOCHROME INTERACTING FACTOR 1 (PIF1). The balance between gibberellic acid (GA) and abscisic acid (ABA) helps to control germination. However, the cellular mechanisms linking PIF1 turnover to hormonal balancing remain elusive. Here, employing far-red light-induced Arabidopsis thaliana seed germination as the experimental system, we identified PLANTACYANIN (PCY) as an inhibitor of germination. It is a blue copper protein associated with the vacuole that is both highly expressed in mature seeds and rapidly silenced during germination. Molecular analyses showed that PIF1 binds to the miR408 promoter and represses miR408 accumulation. This in turn posttranscriptionally modulates PCY abundance, forming the PIF1-miR408-PCY repression cascade for translating PIF1 turnover to PCY turnover during early germination. Genetic analysis, RNA-sequencing, and hormone quantification revealed that PCY is necessary and sufficient to maintain the PIF1-mediated seed transcriptome and the low-GA-high-ABA state. Furthermore, we found that PCY domain organization and regulation by miR408 are conserved features in seed plants. These results revealed a cellular mechanism whereby PIF1-relayed external light signals are converted through PCY turnover to internal hormonal profiles for controlling seed germination.
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Affiliation(s)
- Anlong Jiang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Zhonglong Guo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Jiawei Pan
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Yanzhi Yang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Yan Zhuang
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Daqing Zuo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Chen Hao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Zhaoxu Gao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Peiyong Xin
- National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinfang Chu
- National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shangwei Zhong
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Lei Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Author for correspondence:
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Kim LJ, Tsuyuki KM, Hu F, Park EY, Zhang J, Iraheta JG, Chia JC, Huang R, Tucker AE, Clyne M, Castellano C, Kim A, Chung DD, DaVeiga CT, Parsons EM, Vatamaniuk OK, Jeong J. Ferroportin 3 is a dual-targeted mitochondrial/chloroplast iron exporter necessary for iron homeostasis in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:215-236. [PMID: 33884692 PMCID: PMC8316378 DOI: 10.1111/tpj.15286] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/10/2021] [Indexed: 05/26/2023]
Abstract
Mitochondria and chloroplasts are organelles with high iron demand that are particularly susceptible to iron-induced oxidative stress. Despite the necessity of strict iron regulation in these organelles, much remains unknown about mitochondrial and chloroplast iron transport in plants. Here, we propose that Arabidopsis ferroportin 3 (FPN3) is an iron exporter that is dual-targeted to mitochondria and chloroplasts. FPN3 is expressed in shoots, regardless of iron conditions, but its transcripts accumulate under iron deficiency in roots. fpn3 mutants cannot grow as well as the wild type under iron-deficient conditions and their shoot iron levels are lower compared with the wild type. Analyses of iron homeostasis gene expression in fpn3 mutants and inductively coupled plasma mass spectrometry (ICP-MS) measurements show that iron levels in the mitochondria and chloroplasts are increased relative to the wild type, consistent with the proposed role of FPN3 as a mitochondrial/plastid iron exporter. In iron-deficient fpn3 mutants, abnormal mitochondrial ultrastructure was observed, whereas chloroplast ultrastructure was not affected, implying that FPN3 plays a critical role in the mitochondria. Overall, our study suggests that FPN3 is essential for optimal iron homeostasis.
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Affiliation(s)
- Leah J. Kim
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | | | - Fengling Hu
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Emily Y. Park
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Jingwen Zhang
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | | | - Ju-Chen Chia
- Soil and Crop Sciences Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853
| | - Rong Huang
- Cornell High Energy Synchrotron Source, Ithaca, New York 14853
| | - Avery E. Tucker
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Madeline Clyne
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Claire Castellano
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Angie Kim
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | - Daniel D. Chung
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
| | | | | | - Olena K. Vatamaniuk
- Soil and Crop Sciences Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853
| | - Jeeyon Jeong
- Department of Biology, Amherst College, Amherst, Massachusetts 01002
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Using Diatom and Apicomplexan Models to Study the Heme Pathway of Chromera velia. Int J Mol Sci 2021; 22:ijms22126495. [PMID: 34204357 PMCID: PMC8233740 DOI: 10.3390/ijms22126495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/11/2021] [Accepted: 06/12/2021] [Indexed: 12/20/2022] Open
Abstract
Heme biosynthesis is essential for almost all living organisms. Despite its conserved function, the pathway’s enzymes can be located in a remarkable diversity of cellular compartments in different organisms. This location does not always reflect their evolutionary origins, as might be expected from the history of their acquisition through endosymbiosis. Instead, the final subcellular localization of the enzyme reflects multiple factors, including evolutionary origin, demand for the product, availability of the substrate, and mechanism of pathway regulation. The biosynthesis of heme in the apicomonad Chromera velia follows a chimeric pathway combining heme elements from the ancient algal symbiont and the host. Computational analyses using different algorithms predict complex targeting patterns, placing enzymes in the mitochondrion, plastid, endoplasmic reticulum, or the cytoplasm. We employed heterologous reporter gene expression in the apicomplexan parasite Toxoplasma gondii and the diatom Phaeodactylum tricornutum to experimentally test these predictions. 5-aminolevulinate synthase was located in the mitochondria in both transfection systems. In T. gondii, the two 5-aminolevulinate dehydratases were located in the cytosol, uroporphyrinogen synthase in the mitochondrion, and the two ferrochelatases in the plastid. In P. tricornutum, all remaining enzymes, from ALA-dehydratase to ferrochelatase, were placed either in the endoplasmic reticulum or in the periplastidial space.
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Wang Q, Zhu B, Chen C, Yuan Z, Guo J, Yang X, Wang S, Lv Y, Liu Q, Yang B, Sun C, Wang P, Deng X. A Single Nucleotide Substitution of GSAM Gene Causes Massive Accumulation of Glutamate 1-Semialdehyde and Yellow Leaf Phenotype in Rice. RICE (NEW YORK, N.Y.) 2021; 14:50. [PMID: 34089406 PMCID: PMC8179877 DOI: 10.1186/s12284-021-00492-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/12/2021] [Indexed: 05/04/2023]
Abstract
BACKGROUND Tetrapyrroles play indispensable roles in various biological processes. In higher plants, glutamate 1-semialdehyde 2,1-aminomutase (GSAM) converts glutamate 1-semialdehyde (GSA) to 5-aminolevulinic acid (ALA), which is the rate-limiting step of tetrapyrrole biosynthesis. Up to now, GSAM genes have been successively identified from many species. Besides, it was found that GSAM could form a dimeric protein with itself by x-ray crystallography. However, no mutant of GSAM has been identified in monocotyledonous plants, and no experiment on interaction of GSAM protein with itself has been reported so far. RESULT We isolated a yellow leaf mutant, ys53, in rice (Oryza sativa). The mutant showed decreased photosynthetic pigment contents, suppressed chloroplast development, and reduced photosynthetic capacity. In consequence, its major agronomic traits were significantly affected. Map-based cloning revealed that the candidate gene was LOC_Os08g41990 encoding GSAM protein. In ys53 mutant, a single nucleotide substitution in this gene caused an amino acid change in the encoded protein, so its ALA-synthesis ability was significantly reduced and GSA was massively accumulated. Complementation assays suggested the mutant phenotype of ys53 could be rescued by introducing wild-type OsGSAM gene, confirming that the point mutation in OsGSAM is the cause of the mutant phenotype. OsGSAM is mainly expressed in green tissues, and its encoded protein is localized to chloroplast. qRT-PCR analysis indicated that the mutation of OsGSAM not only affected the expressions of tetrapyrrole biosynthetic genes, but also influenced those of photosynthetic genes in rice. In addition, the yeast two-hybrid experiment showed that OsGSAM protein could interact with itself, which could largely depend on the two specific regions containing the 81th-160th and the 321th-400th amino acid residues at its N- and C-terminals, respectively. CONCLUSIONS We successfully characterized rice GSAM gene by a yellow leaf mutant and map-based cloning approach. Meanwhile, we verified that OsGSAM protein could interact with itself mainly by means of the two specific regions of amino acid residues at its N- and C-terminals, respectively.
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Affiliation(s)
- Qian Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Baiyang Zhu
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Congping Chen
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Zhaodi Yuan
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jia Guo
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Xiaorong Yang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - San Wang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Yan Lv
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Qingsong Liu
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Bin Yang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Changhui Sun
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Pingrong Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China.
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.
| | - Xiaojian Deng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China.
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.
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50
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Cejudo FJ, González MC, Pérez-Ruiz JM. Redox regulation of chloroplast metabolism. PLANT PHYSIOLOGY 2021; 186:9-21. [PMID: 33793865 PMCID: PMC8154093 DOI: 10.1093/plphys/kiaa062] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/16/2020] [Indexed: 05/08/2023]
Abstract
Regulation of enzyme activity based on thiol-disulfide exchange is a regulatory mechanism in which the protein disulfide reductase activity of thioredoxins (TRXs) plays a central role. Plant chloroplasts are equipped with a complex set of up to 20 TRXs and TRX-like proteins, the activity of which is supported by reducing power provided by photosynthetically reduced ferredoxin (FDX) with the participation of a FDX-dependent TRX reductase (FTR). Therefore, the FDX-FTR-TRXs pathway allows the regulation of redox-sensitive chloroplast enzymes in response to light. In addition, chloroplasts contain an NADPH-dependent redox system, termed NTRC, which allows the use of NADPH in the redox network of these organelles. Genetic approaches using mutants of Arabidopsis (Arabidopsis thaliana) in combination with biochemical and physiological studies have shown that both redox systems, NTRC and FDX-FTR-TRXs, participate in fine-tuning chloroplast performance in response to changes in light intensity. Moreover, these studies revealed the participation of 2-Cys peroxiredoxin (2-Cys PRX), a thiol-dependent peroxidase, in the control of the reducing activity of chloroplast TRXs as well as in the rapid oxidation of stromal enzymes upon darkness. In this review, we provide an update on recent findings regarding the redox regulatory network of plant chloroplasts, focusing on the functional relationship of 2-Cys PRXs with NTRC and the FDX-FTR-TRXs redox systems for fine-tuning chloroplast performance in response to changes in light intensity and darkness. Finally, we consider redox regulation as an additional layer of control of the signaling function of the chloroplast.
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Affiliation(s)
- Francisco Javier Cejudo
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla—Consejo Superior de Investigaciones Científicas, Avda. Américo Vespucio 49, 41092 Sevilla, Spain
- Author for communication:
| | - María-Cruz González
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla—Consejo Superior de Investigaciones Científicas, Avda. Américo Vespucio 49, 41092 Sevilla, Spain
| | - Juan Manuel Pérez-Ruiz
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla—Consejo Superior de Investigaciones Científicas, Avda. Américo Vespucio 49, 41092 Sevilla, Spain
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