1
|
Su T, Liu H, Wu Y, Wang J, He F, Li H, Li S, Wang L, Li L, Cao J, Lu Q, Zhao X, Xiang H, Lin C, Lu S, Liu B, Kong F, Fang C. Soybean hypocotyl elongation is regulated by a MYB33-SWEET11/21-GA2ox8c module involving long-distance sucrose transport. PLANT BIOTECHNOLOGY JOURNAL 2024. [PMID: 38861663 DOI: 10.1111/pbi.14409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/01/2024] [Accepted: 05/27/2024] [Indexed: 06/13/2024]
Abstract
The length of hypocotyl affects the height of soybean and lodging resistance, thus determining the final grain yield. However, research on soybean hypocotyl length is scarce, and the regulatory mechanisms are not fully understood. Here, we identified a module controlling the transport of sucrose, where sucrose acts as a messenger moved from cotyledon to hypocotyl, regulating hypocotyl elongation. This module comprises four key genes, namely MYB33, SWEET11, SWEET21 and GA2ox8c in soybean. In cotyledon, MYB33 is responsive to sucrose and promotes the expression of SWEET11 and SWEET21, thereby facilitating sucrose transport from the cotyledon to the hypocotyl. Subsequently, sucrose transported from the cotyledon up-regulates the expression of GA2ox8c in the hypocotyl, which ultimately affects the length of the hypocotyl. During the domestication and improvement of soybean, an allele of MYB33 with enhanced abilities to promote SWEET11 and SWEET21 has gradually become enriched in landraces and cultivated varieties, SWEET11 and SWEET21 exhibit high conservation and have undergone a strong purified selection and GA2ox8c is under a strong artificial selection. Our findings identify a new molecular pathway in controlling soybean hypocotyl elongation and provide new insights into the molecular mechanism of sugar transport in soybean.
Collapse
Affiliation(s)
- Tong Su
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Huan Liu
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Yichun Wu
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Jianhao Wang
- Vegetables Research Institute, Guangdong Academy of Agricultural Sciences, Guangdong Key Laboratory for New Technology Research of Vegetables, Guangzhou, China
| | - Fanglei He
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
- Institute of Improvement and Utilization of Characteristic Resource Plants, College of Agriculture and Biotechnology, Yunnan Agricultural University, Kunming, China
| | - Haiyang Li
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Shichen Li
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Lingshuang Wang
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Lanxin Li
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Jie Cao
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Qiulian Lu
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Xiaohui Zhao
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Hongtao Xiang
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
- Suihua Branch, Heilongjiang Academy of Agricultural Machinery Sciences, Suihua, China
| | - Chun Lin
- Institute of Improvement and Utilization of Characteristic Resource Plants, College of Agriculture and Biotechnology, Yunnan Agricultural University, Kunming, China
| | - Sijia Lu
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Baohui Liu
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Fanjiang Kong
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Chao Fang
- Guangdong Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, China
| |
Collapse
|
2
|
Reyer A, Bazihizina N, Jaślan J, Scherzer S, Schäfer N, Jaślan D, Becker D, Müller TD, Pommerrenig B, Neuhaus HE, Marten I, Hedrich R. Sugar beet PMT5a and STP13 carriers suitable for proton-driven plasma membrane sucrose and glucose import in taproots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:2219-2232. [PMID: 38602250 DOI: 10.1111/tpj.16740] [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: 11/27/2023] [Revised: 02/26/2024] [Accepted: 03/18/2024] [Indexed: 04/12/2024]
Abstract
Sugar beet (Beta vulgaris) is the major sugar-producing crop in Europe and Northern America, as the taproot stores sucrose at a concentration of around 20%. Genome sequence analysis together with biochemical and electrophysiological approaches led to the identification and characterization of the TST sucrose transporter driving vacuolar sugar accumulation in the taproot. However, the sugar transporters mediating sucrose uptake across the plasma membrane of taproot parenchyma cells remained unknown. As with glucose, sucrose stimulation of taproot parenchyma cells caused inward proton fluxes and plasma membrane depolarization, indicating a sugar/proton symport mechanism. To decipher the nature of the corresponding proton-driven sugar transporters, we performed taproot transcriptomic profiling and identified the cold-induced PMT5a and STP13 transporters. When expressed in Xenopus laevis oocytes, BvPMT5a was characterized as a voltage- and H+-driven low-affinity glucose transporter, which does not transport sucrose. In contrast, BvSTP13 operated as a high-affinity H+/sugar symporter, transporting glucose better than sucrose, and being more cold-tolerant than BvPMT5a. Modeling of the BvSTP13 structure with bound mono- and disaccharides suggests plasticity of the binding cleft to accommodate the different saccharides. The identification of BvPMT5a and BvSTP13 as taproot sugar transporters could improve breeding of sugar beet to provide a sustainable energy crop.
Collapse
Affiliation(s)
- Antonella Reyer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Nadia Bazihizina
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, 50019, Sesto Fiorentino, Italy
| | - Justyna Jaślan
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Sönke Scherzer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Nadine Schäfer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Dawid Jaślan
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians-Universität, 80336, Munich, Germany
| | - Dirk Becker
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Thomas D Müller
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Benjamin Pommerrenig
- Plant Physiology, University of Kaiserslautern, 67663, Kaiserslautern, Germany
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Resistance Research and Stress Tolerance, Quedlinburg, 06484, Germany
| | - H Ekkehard Neuhaus
- Plant Physiology, University of Kaiserslautern, 67663, Kaiserslautern, Germany
| | - Irene Marten
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Rainer Hedrich
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| |
Collapse
|
3
|
Scheible N, Henning PM, McCubbin AG. Calmodulin-Domain Protein Kinase PiCDPK1 Interacts with the 14-3-3-like Protein NtGF14 to Modulate Pollen Tube Growth. PLANTS (BASEL, SWITZERLAND) 2024; 13:451. [PMID: 38337984 PMCID: PMC10857193 DOI: 10.3390/plants13030451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
Calcium-mediated signaling pathways are known to play important roles in the polar growth of pollen tubes. The calcium-dependent protein kinase, PiCDPK1, has been shown to be involved in regulating this process through interaction with a guanine dissociation inhibitor, PiRhoGDI1. To more fully understand the role of PiCDPK1 in pollen tube extension, we designed a pull-down study to identify additional substrates of this kinase. These experiments identified 123 putative interactors. Two of the identified proteins were predicted to directly interact with PiCDPK1, and this possibility was investigated in planta. The first, NtGF14, a 14-3-3-like protein, did not produce a noticeable phenotype when overexpressed in pollen alone but partially rescued the spherical tube phenotype caused by PiCDPK1 over-expression when co-over-expressed with the kinase. The second, NtREN1, a GTPase activating protein (GAP), severely inhibited pollen tube germination when over-expressed, and its co-over-expression with PiCDPK1 did not substantially affect this phenotype. These results suggest a novel in vivo interaction between NtGF14 and PiCDPK1 but do not support the direct interaction between PiCDPK1 and NtREN1. We demonstrate the utility of the methodology used to identify potential protein interactions while confirming the necessity of additional studies to confirm their validity. Finally, additional support was found for intersection between PiCDPK1 and RopGTPase pathways to control polar growth at the pollen tube tip.
Collapse
Affiliation(s)
| | | | - Andrew G. McCubbin
- School of Biological Sciences, Washington State University, Pullman, WA 99164, USA; (N.S.); (P.M.H.)
| |
Collapse
|
4
|
Zhou X, Zhang Q, Zhao Y, Ding S, Yu GH. Integrated Multi-Omics Analyses Reveal That Autophagy-Mediated Cellular Metabolism Is Required for the Initiation of Pollen Germination. Int J Mol Sci 2023; 24:15014. [PMID: 37834462 PMCID: PMC10573924 DOI: 10.3390/ijms241915014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/25/2023] [Accepted: 09/30/2023] [Indexed: 10/15/2023] Open
Abstract
Autophagy is an evolutionarily conserved mechanism for degrading and recycling various cellular components, functioning in both normal development and stress conditions. This process is tightly regulated by a set of autophagy-related (ATG) proteins, including ATG2 in the ATG9 cycling system and ATG5 in the ATG12 conjugation system. Our recent research demonstrated that autophagy-mediated compartmental cytoplasmic deletion is essential for pollen germination. However, the precise mechanisms through which autophagy regulates pollen germination, ensuring its fertility, remain largely unknown. Here, we applied multi-omics analyses, including transcriptomic and metabolomic approaches, to investigate the downstream pathways of autophagy in the process of pollen germination. Although ATG2 and ATG5 play similar roles in regulating pollen germination, high-throughput transcriptomic analysis reveals that silencing ATG5 has a greater impact on the transcriptome than silencing ATG2. Cross-comparisons of transcriptome and proteome analysis reveal that gene expression at the mRNA level and protein level is differentially affected by autophagy. Furthermore, high-throughput metabolomics analysis demonstrates that pathways related to amino acid metabolism and aminoacyl-tRNA biosynthesis were affected by both ATG2 and ATG5 silencing. Collectively, our multi-omics analyses reveal the central role of autophagy in cellular metabolism, which is critical for initiating pollen germination and ensuring pollen fertility.
Collapse
Affiliation(s)
| | | | | | | | - Guang-Hui Yu
- College of Life Sciences, South-Central Minzu University, Wuhan 430074, China; (X.Z.)
| |
Collapse
|
5
|
Wang G, Chen R, Han X, Xue X. Effects and Mechanism Analysis of Non-Bagging and Bagging Cultivation on the Growth and Content Change of Specific Substances of Fuji Apple Fruit. PLANTS (BASEL, SWITZERLAND) 2023; 12:3309. [PMID: 37765473 PMCID: PMC10536194 DOI: 10.3390/plants12183309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/06/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023]
Abstract
The experiment was conducted at the Taidong Base of Shandong Institute of Pomology, Tai'an City, Shandong Province, China, from May to October 2022. Using Fuji Apple Tianhong.2/SH/Malus robusta (M. robusta) as experimental materials, the differences and mechanisms of the effects of non-bagging and bagging cultivation on the growth and changes in some substance content of Fuji apple fruits were studied. The results showed that compared with bagging, non-bagging cultivation increased single fruit weight and decreased fruit shape index, increased fruit sugar content, reduced acid content, and increased taste. It increased the content of vitamin C (VC) and protein in the fruit, increased the types and content of aromatic components in the fruit, significantly increased the activity of sugar- and acid-related enzymes, and improved the antioxidant capacity of the fruit. Compared to bagging cultivation, non-bagging cultivation improved the weight, taste (sugar acid ratio), and aroma of Fuji fruit, which is related to increasing the content of auxin (IAA), cytokinin (ZR), and salicylic acid (SA) and reducing the content of abscisic acid (ABA) in the fruit, as well as increasing the content of medium and trace elements calcium (Ca), iron (Fe), manganese (Mg), and boron (B). One of the mechanisms involved is the significant increase in gene expression related to phenylpropanoid biosynthesis, pentose and glucuronate interconversion, starch and sucrose metabolism, zeatin biosynthesis, microtubules, motor proteins microtubule movement, xyloglucan metabolic process, cell division, and peroxidase activity. In short, non-bagging cultivation is more conducive to improving the intrinsic quality and flavor development of Fuji apples, and one of the mechanisms is that non-bagging cultivation is beneficial for increasing the expression of related genes.
Collapse
Affiliation(s)
| | | | | | - Xiaomin Xue
- Shandong Institute of Pomology, Taian 271000, China; (G.W.); (R.C.); (X.H.)
| |
Collapse
|
6
|
Tian X, Zou H, Xiao Q, Xin H, Zhu L, Li Y, Ma B, Cui N, Ruan YL, Ma F, Li M. Uptake of glucose from the rhizosphere, mediated by apple MdHT1.2, regulates carbohydrate allocation. PLANT PHYSIOLOGY 2023; 193:410-425. [PMID: 37061824 DOI: 10.1093/plphys/kiad221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 04/12/2023] [Indexed: 06/19/2023]
Abstract
Plant roots can absorb sugars from the rhizosphere, which reduces the consumption of carbon derived from photosynthesis. However, the underlying mechanisms that roots use to control sugar absorption from soil are poorly understood. Here, we identified an apple (Malus × domestica Borkh.) hexose transporter, MdHT1.2, that functions on the root epidermis to absorb glucose (Glc) from the rhizosphere. Based on RNA-seq data, MdHT1.2 showed the highest expression level among 29 MdHT genes in apple roots. Biochemical analyses demonstrated that MdHT1.2 was mainly expressed in the epidermal cells of fine roots, and its protein was located on the plasma membrane. The roots of transgenic apple and Solanum lycopersicum lines overexpressing MdHT1.2 had an increased capability to absorb Glc when fed with [13C]-labeled Glc or 2-NBDG, whereas silencing MdHT1.2 in apple showed the opposite results. Further studies established that MdHT1.2-mediated Glc absorption from the rhizosphere changed the carbon assimilate allocation between apple shoot and root, which regulated plant growth. Additionally, a grafting experiment in tomato confirmed that increasing the Glc uptake capacity in the root overexpressing MdHT1.2 could facilitate carbohydrate partitioning to the fruit. Collectively, our study demonstrated that MdHT1.2 functions on the root epidermis to absorb rhizospheric Glc, which regulates the carbohydrate allocation for plant growth and fruit sugar accumulation.
Collapse
Affiliation(s)
- Xiaocheng Tian
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Hui Zou
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Qian Xiao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Haijun Xin
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Lingcheng Zhu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Yuxing Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Baiquan Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Ningbo Cui
- State Key Laboratory of Hydraulics and Mountain River Engineering & College of Water Resource and Hydropower, Sichuan University, Chengdu 610065, China
| | - Yong-Ling Ruan
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| | - Mingjun Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Shaanxi Key Laboratory of Apple, Northwest A&F University, Yangling 712100, China
| |
Collapse
|
7
|
Koyamatsu D, Otsubo M, Ohira T, Sato MP, Suzuki-Masuko H, Shiota T, Takenaka Takano K, Ozeki M, Otsuka K, Ogura Y, Hayashi T, Watanabe M, Inaba T, Ito-Inaba Y. Molecular characterization of SrSTP14, a sugar transporter from thermogenic skunk cabbage, and its possible role in developing pollen. PHYSIOLOGIA PLANTARUM 2023; 175:e13957. [PMID: 37338180 DOI: 10.1111/ppl.13957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 06/13/2023] [Accepted: 06/15/2023] [Indexed: 06/21/2023]
Abstract
In floral thermogenesis, sugars play an important role not only as energy providers but also as growth and development facilitators. Yet, the mechanisms underlying sugar translocation and transport in thermogenic plants remain to be studied. Asian skunk cabbage (Symplocarpus renifolius) is a species that can produce durable and intense heat in its reproductive organ, the spadix. Significant morphological and developmental changes in the stamen are well-characterized in this plant. In this study, we focused on the sugar transporters (STPs), SrSTP1 and SrSTP14, whose genes were identified by RNA-seq as the upregulated STPs during thermogenesis. Real-time PCR confirmed that mRNA expression of both STP genes was increased from the pre-thermogenic to the thermogenic stage in the spadix, where it is predominantly expressed in the stamen. SrSTP1 and SrSTP14 complemented the growth defects of a hexose transporter-deficient yeast strain, EBY4000, on media containing 0.02, 0.2, and 2% (w/v) glucose and galactose. Using a recently developed transient expression system in skunk cabbage leaf protoplasts, we revealed that SrSTP1 and SrSTP14-GFP fusion proteins were mainly localized to the plasma membrane. To dig further into the functional analysis of SrSTPs, tissue-specific localization of SrSTPs was investigated by in situ hybridization. Using probes for SrSTP14, mRNA expression was observed in the microspores within the developing anther at the thermogenic female stage. These results indicate that SrSTP1 and SrSTP14 transport hexoses (e.g., glucose and galactose) at the plasma membrane and suggest that SrSTP14 may play a role in pollen development through the uptake of hexoses into pollen precursor cells.
Collapse
Affiliation(s)
- Daiki Koyamatsu
- Department of Agricultural and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Miyabi Otsubo
- Department of Agricultural and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Tomonori Ohira
- Department of Agricultural and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Mitsuhiko P Sato
- Department of Frontier Research and Development, Kazusa DNA Research Institute, Kisarazu, Japan
| | | | - Takuya Shiota
- Organization for Promotion of Tenure Track, University of Miyazaki, Miyazaki, Japan
- Frontier Science Research Center, University of Miyazaki, Miyazaki, Japan
| | - Kohei Takenaka Takano
- Natural Environment Division, Nagano Environmental Conservation Research Institute, Nagano, Japan
| | - Masaaki Ozeki
- Natural Environment Division, Nagano Environmental Conservation Research Institute, Nagano, Japan
| | - Koichi Otsuka
- Natural Environment Division, Nagano Environmental Conservation Research Institute, Nagano, Japan
| | - Yoshitoshi Ogura
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Fukuoka, Japan
| | - Tetsuya Hayashi
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masao Watanabe
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Takehito Inaba
- Department of Agricultural and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Yasuko Ito-Inaba
- Department of Agricultural and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| |
Collapse
|
8
|
Seitz J, Reimann TM, Fritz C, Schröder C, Knab J, Weber W, Stadler R. How pollen tubes fight for food: the impact of sucrose carriers and invertases of Arabidopsis thaliana on pollen development and pollen tube growth. FRONTIERS IN PLANT SCIENCE 2023; 14:1063765. [PMID: 37469768 PMCID: PMC10352115 DOI: 10.3389/fpls.2023.1063765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 06/05/2023] [Indexed: 07/21/2023]
Abstract
Pollen tubes of higher plants grow very rapidly until they reach the ovules to fertilize the female gametes. This growth process is energy demanding, however, the nutrition strategies of pollen are largely unexplored. Here, we studied the function of sucrose transporters and invertases during pollen germination and pollen tube growth. RT-PCR analyses, reporter lines and knockout mutants were used to study gene expression and protein function in pollen. The genome of Arabidopsis thaliana contains eight genes that encode functional sucrose/H+ symporters. Apart from AtSUC2, which is companion cell specific, all other AtSUC genes are expressed in pollen tubes. AtSUC1 is present in developing pollen and seems to be the most important sucrose transporter during the fertilization process. Pollen of an Atsuc1 knockout plant contain less sucrose and have defects in pollen germination and pollen tube growth. The loss of other sucrose carriers affects neither pollen germination nor pollen tube growth. A multiple knockout line Atsuc1Atsuc3Atsuc8Atsuc9 shows a phenotype that is comparable to the Atsuc1 mutant line. Loss of AtSUC1 can`t be complemented by AtSUC9, suggesting a special function of AtSUC1. Besides sucrose carriers, pollen tubes also synthesize monosaccharide carriers of the AtSTP family as well as invertases. We could show that AtcwINV2 and AtcwINV4 are expressed in pollen, AtcwINV1 in the transmitting tissue and AtcwINV5 in the funiculi of the ovary. The vacuolar invertase AtVI2 is also expressed in pollen, and a knockout of AtVI2 leads to a severe reduction in pollen germination. Our data indicate that AtSUC1 mediated sucrose accumulation during late stages of pollen development and cleavage of vacuolar sucrose into monosaccharides is important for the process of pollen germination.
Collapse
Affiliation(s)
- Jessica Seitz
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Theresa Maria Reimann
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Carolin Fritz
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Carola Schröder
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Johanna Knab
- Cell Biology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Walter Weber
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Ruth Stadler
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
9
|
Li H, Feng B, Li J, Fu W, Wang W, Chen T, Liu L, Wu Z, Peng S, Tao L, Fu G. RGA1 alleviates low-light-repressed pollen tube elongation by improving the metabolism and allocation of sugars and energy. PLANT, CELL & ENVIRONMENT 2023; 46:1363-1383. [PMID: 36658612 DOI: 10.1111/pce.14547] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/08/2023] [Accepted: 01/18/2023] [Indexed: 06/17/2023]
Abstract
Low-light stress compromises photosynthetic and energy efficiency and leads to spikelet sterility; however, the effect of low-light stress on pollen tube elongation in the pistil remains poorly understood. The gene RGA1, which encodes a Gα-subunit of the heterotrimeric G-protein, enhanced low-light tolerance at anthesis by preventing the cessation of pollen tube elongation in the pistil of rice plants. In this process, marked increases in the activities of acid invertase (INV), sucrose synthase (SUS) and mitochondrial respiratory electron transport chain complexes, as well as the relative expression levels of SUTs (sucrose transporter), SWEETs (sugars will eventually be exported transporters), SUSs, INVs, CINs (cell-wall INV 1), SnRK1A (sucrose-nonfermenting 1-related kinase 1) and SnRK1B, were observed in OE-1 plants. Accordingly, notable increases in contents of ATP and ATPase were presented in OE-1 plants under low-light conditions, while they were decreased in d1 plants. Importantly, INV and ATPase activators (sucrose and Na2 SO3 , respectively) increased spikelet fertility by improving the energy status in the pistil under low-light conditions, and the ATPase inhibitor Na2 VO4 induced spikelet sterility and decreased ATPase activity. These results suggest that RGA1 could alleviate the low-light stress-induced impairment of pollen tube elongation to increase spikelet fertility by promoting sucrose unloading in the pistil and improving the metabolism and allocation of energy.
Collapse
Affiliation(s)
- Hubo Li
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
- Crop Production and Physiology Center (CPPC), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Baohua Feng
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Juncai Li
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
- Agronomy College, Jilin Agricultural University, Changchun, China
| | - Weimeng Fu
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Wenting Wang
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Tingting Chen
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Lianmeng Liu
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Zhihai Wu
- Agronomy College, Jilin Agricultural University, Changchun, China
| | - Shaobing Peng
- Crop Production and Physiology Center (CPPC), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Longxing Tao
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Guanfu Fu
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
- Agronomy College, Jilin Agricultural University, Changchun, China
| |
Collapse
|
10
|
Xu W, Liu Z, Zhao Z, Zhang S, Li M, Guo D, Liu JH, Li C. The functional analysis of sugar transporter proteins in sugar accumulation and pollen tube growth in pummelo ( Citrus grandis). FRONTIERS IN PLANT SCIENCE 2023; 13:1106219. [PMID: 36684762 PMCID: PMC9846575 DOI: 10.3389/fpls.2022.1106219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Sugar transporter proteins (STPs) play vital roles in sugar transport and allocation of carbon sources in plants. However, the evolutionary dynamics of this important gene family and their functions are still largely unknown in citrus, which is the largest fruit crop in the world. In this study, fourteen non-redundant CgSTP family members were identified in pummelo (Citrus grandis). A comprehensive analysis based on the biochemical characteristics, the chromosomal location, the exon-intron structures and the evolutionary relationships demonstrated the conservation and the divergence of CgSTPs. Moreover, CgSTP4, 11, 13, 14 were proofed to be localized in plasma membrane and have glucose transport activity in yeast. The hexose content were significantly increased with the transient overexpression of CgSTP11 and CgSTP14. In addition, antisense repression of CgSTP4 induced the shorter pollen tube length in vitro, implying the potential role of CgSTP4 in pummelo pollen tube growth. Taken together, this work explored a framework for understanding the physiological role of CgSTPs and laid a foundation for future functional studies of these members in citrus species.
Collapse
Affiliation(s)
- Weiwei Xu
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Ziyan Liu
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Zeqi Zhao
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Shuhang Zhang
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Mengdi Li
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Dayong Guo
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Ji-Hong Liu
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
| | - Chunlong Li
- Key Laboratory of Horticultural Plant Biology Ministry of Education (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
| |
Collapse
|
11
|
Fakher B, Jakada BH, Greaves JG, Wang L, Niu X, Cheng Y, Zheng P, Aslam M, Qin Y, Wang X. Identification and expression analysis of pineapple sugar transporters reveal their role in the development and environmental response. FRONTIERS IN PLANT SCIENCE 2022; 13:964897. [PMID: 36352877 PMCID: PMC9638087 DOI: 10.3389/fpls.2022.964897] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
In plants, sugars are required for several essential functions, including growth, storage, signaling, defense and reproduction. Sugar transporters carry out the controlled movement of sugars from source (leaves) to sink (fruits and roots) tissues and determine the overall development of the plant. Various types of sugar transporter families have been described in plants, including sucrose transporters (SUC/SUT), monosaccharide transporter (MST) and SWEET (from "Sugar Will Eventually be Exported Transporters"). However, the information about pineapple sugar transporters is minimal. This study systematically identified and classified 45 MST and 4 SUC/SUT genes in the pineapple genome. We found that the expression patterns of sugar transporter genes have a spatiotemporal expression in reproductive and vegetative tissues indicating their pivotal role in reproductive growth and development. Besides, different families of sugar transporters have a diel expression pattern in photosynthetic and non-photosynthetic tissues displaying circadian rhythm associated participation of sugar transporters in the CAM pathway. Moreover, regulation of the stress-related sugar transporters during cold stress indicates their contribution to cold tolerance in pineapple. Heterologous expression (yeast complementation assays) of sugar transporters in a mutant yeast strain suggested that SUT1/2 have the ability to transport sucrose, and STP13, STP26, pGlcT-L2 and TMT4 are able to transport glucose, whereas SWEET11/13 transport both sucrose and fructose. The information provided here would help researchers further explore the underlying molecular mechanism involved in the sugar metabolism of pineapple.
Collapse
Affiliation(s)
- Beenish Fakher
- Guangxi Key Lab of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
| | - Bello Hassan Jakada
- Horticulture Research Institute, Guangxi Academy of Agricultural Sciences, Nanning Investigation Station of South Subtropical Fruit Trees, Ministry of Agriculture, Nanning, China
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Joseph G. Greaves
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lulu Wang
- Guangxi Key Lab of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
| | - Xiaoping Niu
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yan Cheng
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ping Zheng
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mohammad Aslam
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yuan Qin
- Guangxi Key Lab of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
- Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaomei Wang
- Horticulture Research Institute, Guangxi Academy of Agricultural Sciences, Nanning Investigation Station of South Subtropical Fruit Trees, Ministry of Agriculture, Nanning, China
| |
Collapse
|
12
|
Integrated bioinformatics, modelling, and gene expression analysis of the putative pentose transporter from Candida tropicalis during xylose fermentation with and without glucose addition. Appl Microbiol Biotechnol 2022; 106:4587-4606. [PMID: 35708749 DOI: 10.1007/s00253-022-12005-x] [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: 07/21/2021] [Revised: 05/18/2022] [Accepted: 05/27/2022] [Indexed: 11/02/2022]
Abstract
The transport of substrates across the cell membrane plays an essential role in nutrient assimilation by yeasts. The establishment of an efficient microbial cell factory, based on the maximum use of available carbon sources, can generate new technologies that allow the full use of lignocellulosic constituents. These technologies are of interest because they could promote the formation of added-value products with economic feasibility. In silico analyses were performed to investigate gene sequences capable of encoding xylose transporter proteins in the Candida tropicalis genome. The current study identified 11 putative transport proteins that have not yet been functionally characterized. A phylogenetic tree highlighted the potential C. tropicalis xylose-transporter proteins CtXUT1, CtXUT4, CtSTL1, CtSTL2, and CtGXT2, which were homologous to previously characterized and reported xylose transporters. Their expression was quantified through real-time qPCR at defined times, determined through a kinetic analysis of the microbial growth curve in the absence/presence of glucose supplemented with xylose as the main carbon source. The results indicated different mRNA expression levels for each gene. CtXUT1 mRNA expression was only found in the absence of glucose in the medium. Maximum CtXUT1 expression was observed in intervals of the highest xylose consumption (21 to 36 h) that corresponded to consumption rates of 1.02 and 0.82 g/L/h in the formulated media, with xylose as the only carbon source and with glucose addition. These observations indicate that CtXUT1 is an important xylose transporter in C. tropicalis. KEY POINTS: • Putative xylose transporter proteins were identified in Candida tropicalis; • The glucose concentration in the cultivation medium plays a key role in xylose transporter regulation; • The transporter gene CtXUT1 has an important role in xylose consumption by Candida tropicalis.
Collapse
|
13
|
Liu T, Bao C, Ban Q, Wang C, Hu T, Wang J. Genome-wide identification of sugar transporter gene family in Brassicaceae crops and an expression analysis in the radish. BMC PLANT BIOLOGY 2022; 22:245. [PMID: 35585498 PMCID: PMC9115943 DOI: 10.1186/s12870-022-03629-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Sugar not only is an important biomacromolecule that plays important roles in plant growth, development, and biotic and abiotic stress tolerance but also provides a skeleton for other macromolecules, such as proteins and nucleic acids. Sugar transporter proteins (STPs) play essential roles in plant sugar transport and ultimately affect the abovementioned life processes. However, the evolutionary dynamics of this important gene family in Brassicaceae crops are still largely unknown, and the functional differentiation of radish STP genes remains unclear. RESULTS In the present study, a comparative genomic study of STP genes in five representative Brassicaceae crops was conducted, and a total of 25, 25, 28, 36 and 49 STP genes were individually identified in Raphanus sativus (Rs), Brassica oleracea (Bo), B. rapa (Br), B. napus (Bn) and B. juncea (Bj), which were divided into four clades by phylogenetic analysis. The number of STP genes was no direct correlation with genome size and the total number of coding genes in Brassicaceae crops, and their physical and chemical properties showed no significant difference. Expression analysis showed that radish STP genes play vital roles not only in flower and seedpod development but also under heavy metal (cadmium, chromium and lead), NaCl and PEG-6000 stresses, Agrobacterium tumefaciens infection, and exogenous sugar treatment. RsSTP13.2 was significantly upregulated in the resistant radish cultivar by A. tumefaciens infection and induced by heavy metal, NaCl and PEG-6000 stress, indicating that it is involved in resistance to both biotic and abiotic stress in radish. CONCLUSIONS The present study provides insights into the evolutionary patterns of the STP gene family in Brassicaceae genomes and provides a theoretical basis for future functional analysis of STP genes in Brassicaceae crops.
Collapse
Affiliation(s)
- Tongjin Liu
- College of Horticulture, Jinling Institute of Technology, Nanjing, 210038 China
| | - Chonglai Bao
- Institute of Vegetable, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021 China
| | - Qiuyan Ban
- College of Horticulture, Jinling Institute of Technology, Nanjing, 210038 China
| | - Changyi Wang
- College of Horticulture, Jinling Institute of Technology, Nanjing, 210038 China
| | - Tianhua Hu
- Institute of Vegetable, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021 China
| | - Jinglei Wang
- Institute of Vegetable, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021 China
| |
Collapse
|
14
|
Wang J, Yu YC, Li Y, Chen LQ. Hexose transporter SWEET5 confers galactose sensitivity to Arabidopsis pollen germination via a galactokinase. PLANT PHYSIOLOGY 2022; 189:388-401. [PMID: 35188197 PMCID: PMC9070816 DOI: 10.1093/plphys/kiac068] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 01/15/2022] [Indexed: 05/12/2023]
Abstract
Galactose is an abundant and essential sugar used for the biosynthesis of many macromolecules in different organisms, including plants. Galactose metabolism is tightly and finely controlled, since excess galactose and its derivatives are inhibitory to plant growth. In Arabidopsis (Arabidopsis thaliana), root growth and pollen germination are strongly inhibited by excess galactose. However, the mechanism of galactose-induced inhibition during pollen germination remains obscure. In this study, we characterized a plasma membrane-localized transporter, Arabidopsis Sugars Will Eventually be Exported Transporter 5, that transports glucose and galactose. SWEET5 protein levels started to accumulate at the tricellular stage of pollen development and peaked in mature pollen, before rapidly declining after pollen germinated. SWEET5 levels are responsible for the dosage-dependent sensitivity to galactose, and galactokinase is essential for these inhibitory effects during pollen germination. However, sugar measurement results indicate that galactose flux dynamics and sugar metabolism, rather than the steady-state galactose level, may explain phenotypic differences between sweet5 and Col-0 in galactose inhibition of pollen germination.
Collapse
Affiliation(s)
- Jiang Wang
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ya-Chi Yu
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | | | | |
Collapse
|
15
|
Xiao Y, Zhou Y, Shi J, Zhang D. OsGAMYBL2 is required for pollen maturation and germination in rice. REPRODUCTION AND BREEDING 2022. [DOI: 10.1016/j.repbre.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|
16
|
Guo Y, Song H, Zhao Y, Qin X, Cao Y, Zhang L. Switch from symplasmic to aspoplasmic phloem unloading in Xanthoceras sorbifolia fruit and sucrose influx XsSWEET10 as a key candidate for Sugar transport. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 313:111089. [PMID: 34763874 DOI: 10.1016/j.plantsci.2021.111089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/30/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
The process of phloem unloading and post-unloading transport of photoassimilate is critical to crop output. Xanthoceras sorbifolia is a woody oil species with great biomass energy prospects in China; however, underproduction of seeds seriously restricts its development. Here, our cytological studies by ultrastructural observation revealed that the sieve element-companion cell complex in carpellary bundle was symplasmically interconnected with surrounding parenchyma cells at the early and late fruit developmental stages, whereas it was symplasmically isolated at middle stage. Consistently, real-time imaging showed that fluorescent tracer 6(5)carboxyfluorescein was confined to phloem strands at middle stage but released into surrounding parenchymal cells at early and late stages. Enzymatic assay showed that sucrose synthase act as the key enzyme catalyzing the progress of Suc degradation post-unloading pathway whether in pericarp or in seed, while vacuolar acid invertase and neutral invertase play compensation roles in sucrose decomposition. Sugar transporter XsSWEET10 had a high expression profile in fruit, especially at middle stage. XsSWEET10 is a plasma membrane-localized protein and heterologous expression in SUC2-deficient yeast strain SUSY7/ura3 confirmed its ability to uptake sucrose. These findings approved the transition from symplasmic to apoplasmic phloem unloading in Xanthoceras sorbifolia fruit and XsSWEET10 as a key candidate in sugar transport.
Collapse
Affiliation(s)
- Yuxiao Guo
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China
| | - Huifang Song
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China
| | - Yangyang Zhao
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China
| | - Xuejing Qin
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China
| | - Yibo Cao
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China
| | - Lingyun Zhang
- Research & Development Center of Blueberry, Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China.
| |
Collapse
|
17
|
Bavnhøj L, Paulsen PA, Flores-Canales JC, Schiøtt B, Pedersen BP. Molecular mechanism of sugar transport in plants unveiled by structures of glucose/H + symporter STP10. NATURE PLANTS 2021; 7:1409-1419. [PMID: 34556835 DOI: 10.1038/s41477-021-00992-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 07/27/2021] [Indexed: 05/28/2023]
Abstract
Sugars are essential sources of energy and carbon and also function as key signalling molecules in plants. Sugar transport proteins (STP) are proton-coupled symporters responsible for uptake of glucose from the apoplast into plant cells. They are integral to organ development in symplastically isolated tissues such as seed, pollen and fruit. Additionally, STPs play a vital role in plant responses to stressors such as dehydration and prevalent fungal infections like rust and mildew. Here we present a structure of Arabidopsis thaliana STP10 in the inward-open conformation at 2.6 Å resolution and a structure of the outward-occluded conformation at improved 1.8 Å resolution, both with glucose and protons bound. The two structures describe key states in the STP transport cycle. Together with molecular dynamics simulations that establish protonation states and biochemical analysis, they pinpoint structural elements, conserved in all STPs, that clarify the basis of proton-to-glucose coupling. These results advance our understanding of monosaccharide uptake, which is essential for plant organ development, and set the stage for bioengineering strategies in crops.
Collapse
Affiliation(s)
- Laust Bavnhøj
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Peter Aasted Paulsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Birgit Schiøtt
- Department of Chemistry, Aarhus University, Aarhus, Denmark
| | | |
Collapse
|
18
|
Chen J, Xue M, Liu H, Fernie AR, Chen W. Exploring the genic resources underlying metabolites through mGWAS and mQTL in wheat: From large-scale gene identification and pathway elucidation to crop improvement. PLANT COMMUNICATIONS 2021; 2:100216. [PMID: 34327326 PMCID: PMC8299079 DOI: 10.1016/j.xplc.2021.100216] [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: 01/20/2021] [Revised: 06/04/2021] [Accepted: 06/28/2021] [Indexed: 05/23/2023]
Abstract
Common wheat (Triticum aestivum L.) is a leading cereal crop, but has lagged behind with respect to the interpretation of the molecular mechanisms of phenotypes compared with other major cereal crops such as rice and maize. The recently available genome sequence of wheat affords the pre-requisite information for efficiently exploiting the potential molecular resources for decoding the genetic architecture of complex traits and identifying valuable breeding targets. Meanwhile, the successful application of metabolomics as an emergent large-scale profiling methodology in several species has demonstrated this approach to be accessible for reaching the above goals. One such productive avenue is combining metabolomics approaches with genetic designs. However, this trial is not as widespread as that for sequencing technologies, especially when the acquisition, understanding, and application of metabolic approaches in wheat populations remain more difficult and even arguably underutilized. In this review, we briefly introduce the techniques used in the acquisition of metabolomics data and their utility in large-scale identification of functional candidate genes. Considerable progress has been made in delivering improved varieties, suggesting that the inclusion of information concerning these metabolites and genes and metabolic pathways enables a more explicit understanding of phenotypic traits and, as such, this procedure could serve as an -omics-informed roadmap for executing similar improvement strategies in wheat and other species.
Collapse
Affiliation(s)
- Jie Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Mingyun Xue
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Hongbo Liu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Alisdair R. Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
| | - Wei Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
19
|
Liu J, Liu M, Tan L, Huai B, Ma X, Pan Q, Zheng P, Wen Y, Zhang Q, Zhao Q, Kang Z, Xiao S. AtSTP8, an endoplasmic reticulum-localised monosaccharide transporter from Arabidopsis, is recruited to the extrahaustorial membrane during powdery mildew infection. THE NEW PHYTOLOGIST 2021; 230:2404-2419. [PMID: 33728642 DOI: 10.1111/nph.17347] [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: 08/29/2020] [Accepted: 03/08/2021] [Indexed: 05/18/2023]
Abstract
Biotrophic pathogens are believed to strategically manipulate sugar transport in host cells to enhance their access to carbohydrates. However, mechanisms of sugar translocation from host cells to biotrophic fungi such as powdery mildew across the plant-haustorium interface remain poorly understood. To investigate this question, systematic subcellular localisation analysis was performed for all the 14 members of the monosaccharide sugar transporter protein (STP) family in Arabidopsis thaliana. The best candidate AtSTP8 was further characterised for its transport properties in Saccharomyces cerevisiae and potential role in powdery mildew infection by gene ablation and overexpression in Arabidopsis. Our results showed that AtSTP8 was mainly localised to the endoplasmic reticulum (ER) and appeared to be recruited to the host-derived extrahaustorial membrane (EHM) induced by powdery mildew. Functional complementation assays in S. cerevisiae suggested that AtSTP8 can transport a broad spectrum of hexose substrates. Moreover, transgenic Arabidopsis plants overexpressing AtSTP8 showed increased hexose concentration in leaf tissues and enhanced susceptibility to powdery mildew. Our data suggested that the ER-localised sugar transporter AtSTP8 may be recruited to the EHM where it may be involved in sugar acquisition by haustoria of powdery mildew from host cells in Arabidopsis.
Collapse
Affiliation(s)
- Jie Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
| | - Mengxue Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Liqiang Tan
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
- College of Horticulture, Sichuan Agricultural University, Chengdu, Sichuan, 611830, China
| | - Baoyu Huai
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xianfeng Ma
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
- Hunan Provincial Key Laboratory for Germplasm Innovation and Utilization of Crop, Hunan Agricultural University, Changsha, Hunan, 410128, China
| | - Qinglin Pan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Peijing Zheng
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yingqiang Wen
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Qiong Zhang
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
| | - Qi Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Science, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Shunyuan Xiao
- Institute of Biosciences and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, 20742, USA
| |
Collapse
|
20
|
Drew D, North RA, Nagarathinam K, Tanabe M. Structures and General Transport Mechanisms by the Major Facilitator Superfamily (MFS). Chem Rev 2021; 121:5289-5335. [PMID: 33886296 PMCID: PMC8154325 DOI: 10.1021/acs.chemrev.0c00983] [Citation(s) in RCA: 159] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Indexed: 12/12/2022]
Abstract
The major facilitator superfamily (MFS) is the largest known superfamily of secondary active transporters. MFS transporters are responsible for transporting a broad spectrum of substrates, either down their concentration gradient or uphill using the energy stored in the electrochemical gradients. Over the last 10 years, more than a hundred different MFS transporter structures covering close to 40 members have provided an atomic framework for piecing together the molecular basis of their transport cycles. Here, we summarize the remarkable promiscuity of MFS members in terms of substrate recognition and proton coupling as well as the intricate gating mechanisms undergone in achieving substrate translocation. We outline studies that show how residues far from the substrate binding site can be just as important for fine-tuning substrate recognition and specificity as those residues directly coordinating the substrate, and how a number of MFS transporters have evolved to form unique complexes with chaperone and signaling functions. Through a deeper mechanistic description of glucose (GLUT) transporters and multidrug resistance (MDR) antiporters, we outline novel refinements to the rocker-switch alternating-access model, such as a latch mechanism for proton-coupled monosaccharide transport. We emphasize that a full understanding of transport requires an elucidation of MFS transporter dynamics, energy landscapes, and the determination of how rate transitions are modulated by lipids.
Collapse
Affiliation(s)
- David Drew
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Rachel A. North
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Kumar Nagarathinam
- Center
of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Lübeck, D-23538, Lübeck, Germany
| | - Mikio Tanabe
- Structural
Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan
| |
Collapse
|
21
|
Kaur H, Manna M, Thakur T, Gautam V, Salvi P. Imperative role of sugar signaling and transport during drought stress responses in plants. PHYSIOLOGIA PLANTARUM 2021; 171:833-848. [PMID: 33583052 DOI: 10.1111/ppl.13364] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 01/31/2021] [Accepted: 02/06/2021] [Indexed: 05/27/2023]
Abstract
Cellular sugar status is essentially maintained during normal growth conditions but is impacted negatively during various environmental perturbations. Drought presents one such unfavorable environmental cue that hampers the photosynthetic fixation of carbon into sugars and affects their transport by lowering the cellular osmotic potential. The transport of cellular sugar is facilitated by a specific set of proteins known as sugar transporters. These transporter proteins are the key determinant of influx/ efflux of various sugars and their metabolite intermediates that support the plant growth and developmental process. Abiotic stress and especially drought stress-mediated injury results in reprogramming of sugar distribution across the cellular and subcellular compartments. Here, we have reviewed the imperative role of sugar accumulation, signaling, and transport under typical and atypical stressful environments. We have discussed the physiological effects of drought on sugar accumulation and transport through different transporter proteins involved in monosaccharide and disaccharide sugar transport. Further, we have illustrated sugar-mediated signaling and regulation of sugar transporter proteins along with the overall crosstalk of this signaling with the phytohormone module of abiotic stress response under osmotic stress. Overall, the present review highlights the critical role of sugar transport, distribution and signaling in plants under drought stress conditions.
Collapse
Affiliation(s)
- Harmeet Kaur
- Plant Molecular Biology, ICAR-National Institute for Plant Biotechnology, New Delhi, India
| | - Mrinalini Manna
- Plant Molecular Biology, National Institute of Plant Genome Research, New Delhi, India
| | - Tanika Thakur
- Agriculture Biotechnology Department, National Agri-Food Biotechnology Institute, Mohali, India
| | - Vibhav Gautam
- Centre of Experimental Medicine and Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Prafull Salvi
- Agriculture Biotechnology Department, National Agri-Food Biotechnology Institute, Mohali, India
| |
Collapse
|
22
|
Datamining and functional environmental genomics reassess the phylogenetics and functional diversity of fungal monosaccharide transporters. Appl Microbiol Biotechnol 2021; 105:647-660. [PMID: 33394157 DOI: 10.1007/s00253-020-11076-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/14/2020] [Accepted: 12/23/2020] [Indexed: 10/22/2022]
Abstract
Sugar transporters are essential components of carbon metabolism and have been extensively studied to control sugar uptake by yeasts and filamentous fungi used in fermentation processes. Based on published information on characterized fungal sugar porters, we show that this protein family encompasses phylogenetically distinct clades. While several clades encompass transporters that seemingly specialized on specific "sugar-related" molecules (e.g., myo-inositol, charged sugar analogs), others include mostly either mono- or di/oligosaccharide low-specificity transporters. To address the issue of substrate specificity of sugar transporters, that protein primary sequences do not fully reveal, we screened "multi-species" soil eukaryotic cDNA libraries for mannose transporters, a sugar that had never been used to select transporters. We obtained 19 environmental transporters, mostly from Basidiomycota and Ascomycota. Among them, one belonged to the unusual "Fucose H+ Symporter" family, which is only known in Fungi for a rhamnose transporter in Aspergillus niger. Functional analysis of the 19 transporters by expression in yeast and for two of them in Xenopus laevis oocytes for electrophysiological measurements indicated that most of them showed a preference for D-mannose over other tested D-C6 (glucose, fructose, galactose) or D-C5 (xylose) sugars. For the several glucose and fructose-negative transporters, growth of the corresponding recombinant yeast strains was prevented on mannose in the presence of one of these sugars that may act by competition for the binding site. Our results highlight the potential of environmental genomics to figure out the functional diversity of key fungal protein families and that can be explored in a context of biotechnology. KEY POINTS: • Most fungal sugar transporters accept several sugars as substrates. • Transporters, belonging to 2 protein families, were isolated from soil cDNA libraries. • Environmental transporters featured novel substrate specificities.
Collapse
|
23
|
Aslani L, Gholami M, Mobli M, Ehsanzadeh P, Bertin N. Decreased sink/source ratio enhances hexose transport in the fruits of greenhouse tomatoes: integration of gene expression and biochemical analyses. PHYSIOLOGIA PLANTARUM 2020; 170:120-131. [PMID: 32356387 DOI: 10.1111/ppl.13116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/24/2020] [Indexed: 05/24/2023]
Abstract
To examine the physiological role of hexose transporters in determining the sink strength of individual fruits, the regulation of hexose transporters gene expression was studied when the sink/source ratio was artificially altered under the greenhouse condition; this was done in two cultivars of tomato, i.e. Grandella and Isabella. The sink/source ratio treatments included: saving one fruit per truss (1F), two fruits per truss (2F), three fruits per truss (3F) and no fruit pruning (control). The results showed that fruit thinning could increase starch, sucrose, and hexose contents in the fruits; it could also modulate the activity of the key enzymes and the expression of tomato hexose transporter genes (LeHTs). Based on the relative transcript levels, all examined LeHTs were unregulated at the end of cell division and the cell expansion stage of fruit development, but the strongest expression level observed at the onset of ripening was related to LeHT1 and LeHT2. Given the concomitancy of cell wall invertase (EC 3.2.1.26) activity and the LeHTs relative expression cell wall, invertase activity seemed to be involved in the expression level of LeHTs. The increased trends of the LeHTs expression with the decrease of the sink/source ratio confirmed the role of hexose transporters in determining the sink strength of the tomato fruits.
Collapse
Affiliation(s)
- Leila Aslani
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Mahdiyeh Gholami
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Mostafa Mobli
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Parviz Ehsanzadeh
- Department of Agronomy and Plant Breeding, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Nadia Bertin
- Unité Plantes et Systèmes de culture Horticoles, French National Institute for Agriculture, Food, and Environment, Avignon, F-84000, France
| |
Collapse
|
24
|
Geiger D. Plant glucose transporter structure and function. Pflugers Arch 2020; 472:1111-1128. [PMID: 32845347 PMCID: PMC8298354 DOI: 10.1007/s00424-020-02449-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 12/01/2022]
Abstract
The carbohydrate D-glucose is the main source of energy in living organisms. In contrast to animals, as well as most fungi, bacteria, and archaea, plants are capable to synthesize a surplus of sugars characterizing them as autothrophic organisms. Thus, plants are de facto the source of all food on earth, either directly or indirectly via feed to livestock. Glucose is stored as polymeric glucan, in animals as glycogen and in plants as starch. Despite serving a general source for metabolic energy and energy storage, glucose is the main building block for cellulose synthesis and represents the metabolic starting point of carboxylate- and amino acid synthesis. Finally yet importantly, glucose functions as signalling molecule conveying the plant metabolic status for adjustment of growth, development, and survival. Therefore, cell-to-cell and long-distance transport of photoassimilates/sugars throughout the plant body require the fine-tuned activity of sugar transporters facilitating the transport across membranes. The functional plant counterparts of the animal sodium/glucose transporters (SGLTs) are represented by the proton-coupled sugar transport proteins (STPs) of the plant monosaccharide transporter(-like) family (MST). In the framework of this special issue on “Glucose Transporters in Health and Disease,” this review gives an overview of the function and structure of plant STPs in comparison to the respective knowledge obtained with the animal Na+-coupled glucose transporters (SGLTs).
Collapse
Affiliation(s)
- Dietmar Geiger
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, Biocenter, University of Wuerzburg, 97082, Wuerzburg, Germany.
| |
Collapse
|
25
|
Chen J, Hu X, Shi T, Yin H, Sun D, Hao Y, Xia X, Luo J, Fernie AR, He Z, Chen W. Metabolite-based genome-wide association study enables dissection of the flavonoid decoration pathway of wheat kernels. PLANT BIOTECHNOLOGY JOURNAL 2020; 18:1722-1735. [PMID: 31930656 PMCID: PMC7336285 DOI: 10.1111/pbi.13335] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 12/29/2019] [Indexed: 05/02/2023]
Abstract
The marriage of metabolomic approaches with genetic design has proven a powerful tool in dissecting diversity in the metabolome and has additionally enhanced our understanding of complex traits. That said, such studies have rarely been carried out in wheat. In this study, we detected 805 metabolites from wheat kernels and profiled their relative contents among 182 wheat accessions, conducting a metabolite-based genome-wide association study (mGWAS) utilizing 14 646 previously described polymorphic SNP markers. A total of 1098 mGWAS associations were detected with large effects, within which 26 candidate genes were tentatively designated for 42 loci. Enzymatic assay of two candidates indicated they could catalyse glucosylation and subsequent malonylation of various flavonoids and thereby the major flavonoid decoration pathway of wheat kernel was dissected. Moreover, numerous high-confidence genes associated with metabolite contents have been provided, as well as more subdivided metabolite networks which are yet to be explored within our data. These combined efforts presented the first step towards realizing metabolomics-associated breeding of wheat.
Collapse
Affiliation(s)
- Jie Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Xin Hu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Taotao Shi
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Huanran Yin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Dongfa Sun
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Yuanfeng Hao
- National Wheat Improvement CenterInstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | - Xianchun Xia
- National Wheat Improvement CenterInstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | - Jie Luo
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
| | | | - Zhonghu He
- National Wheat Improvement CenterInstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | - Wei Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| |
Collapse
|
26
|
Pommerrenig B, Müdsam C, Kischka D, Neuhaus HE. Treat and trick: common regulation and manipulation of sugar transporters during sink establishment by the plant and the pathogen. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3930-3940. [PMID: 32242225 DOI: 10.1093/jxb/eraa168] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 04/01/2020] [Indexed: 06/11/2023]
Abstract
Sugar transport proteins are crucial for the coordinated allocation of sugars. In this Expert View we summarize recent key findings of the roles and regulation of sugar transporters in inter- and intracellular transport by focusing on applied approaches, demonstrating how sucrose transporter activity may alter source and sink dynamics and their identities. The plant itself alters its sugar transport activity in a developmentally dependent manner to either establish or load endogenous sinks, for example, during tuber formation and filling. Pathogens represent aberrant sinks that trigger the plant to induce the same processes, resulting in loss of carbon assimilates. We explore common mechanisms of intrinsic, developmentally dependent processes and aberrant, pathogen-induced manipulation of sugar transport. Transporter activity may also be targeted by breeding or genetic modification approaches in crop plants to alter source and sink metabolism upon the overexpression or heterologous expression of these proteins. In addition, we highlight recent progress in the use of sugar analogs to study these processes in vivo.
Collapse
Affiliation(s)
| | - Christina Müdsam
- Biochemistry, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Dominik Kischka
- Biochemistry, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | | |
Collapse
|
27
|
Flütsch S, Nigro A, Conci F, Fajkus J, Thalmann M, Trtílek M, Panzarová K, Santelia D. Glucose uptake to guard cells via STP transporters provides carbon sources for stomatal opening and plant growth. EMBO Rep 2020; 21:e49719. [PMID: 32627357 PMCID: PMC7403697 DOI: 10.15252/embr.201949719] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 05/08/2020] [Accepted: 05/13/2020] [Indexed: 01/16/2023] Open
Abstract
Guard cells on the leaf epidermis regulate stomatal opening for gas exchange between plants and the atmosphere, allowing a balance between photosynthesis and transpiration. Given that guard cells possess several characteristics of sink tissues, their metabolic activities should largely depend on mesophyll-derived sugars. Early biochemical studies revealed sugar uptake into guard cells. However, the transporters that are involved and their relative contribution to guard cell function are not yet known. Here, we identified the monosaccharide/proton symporters Sugar Transport Protein 1 and 4 (STP1 and STP4) as the major plasma membrane hexose sugar transporters in the guard cells of Arabidopsis thaliana. We show that their combined action is required for glucose import to guard cells, providing carbon sources for starch accumulation and light-induced stomatal opening that are essential for plant growth. These findings highlight mesophyll-derived glucose as an important metabolite connecting stomatal movements with photosynthesis.
Collapse
Affiliation(s)
- Sabrina Flütsch
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland.,Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Arianna Nigro
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Franco Conci
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Jiří Fajkus
- Photon Systems Instruments (PSI), Drasov, Czech Republic
| | - Matthias Thalmann
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Martin Trtílek
- Photon Systems Instruments (PSI), Drasov, Czech Republic
| | | | - Diana Santelia
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland.,Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| |
Collapse
|
28
|
Komaitis F, Kalliampakou K, Botou M, Nikolaidis M, Kalloniati C, Skliros D, Du B, Rennenberg H, Amoutzias GD, Frillingos S, Flemetakis E. Molecular and physiological characterization of the monosaccharide transporters gene family in Medicago truncatula. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3110-3125. [PMID: 32016431 DOI: 10.1093/jxb/eraa055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
Monosaccharide transporters (MSTs) represent key components of the carbon transport and partitioning mechanisms in plants, mediating the cell-to-cell and long-distance distribution of a wide variety of monosaccharides. In this study, we performed a thorough structural, molecular, and physiological characterization of the monosaccharide transporter gene family in the model legume Medicago truncatula. The complete set of MST family members was identified with a novel bioinformatic approach. Prolonged darkness was used as a test condition to identify the relevant transcriptomic and metabolic responses combining MST transcript profiling and metabolomic analysis. Our results suggest that MSTs play a pivotal role in the efficient partitioning and utilization of sugars, and possibly in the mechanisms of carbon remobilization in nodules upon photosynthate-limiting conditions, as nodules are forced to acquire a new role as a source of both C and N.
Collapse
Affiliation(s)
- Fotios Komaitis
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Katerina Kalliampakou
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Maria Botou
- Laboratory of Biological Chemistry, Department of Medicine, University of Ioannina, Ioannina, Greece
| | - Marios Nikolaidis
- Bioinformatics Laboratory, Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Chrysanthi Kalloniati
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Dimitrios Skliros
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Baoguo Du
- Institute of Forest Sciences, Faculty of Environment and Natural Resources, Albert Ludwig University of Freiburg, Freiburg, Germany
| | - Heinz Rennenberg
- Institute of Forest Sciences, Faculty of Environment and Natural Resources, Albert Ludwig University of Freiburg, Freiburg, Germany
- College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Grigoris D Amoutzias
- Bioinformatics Laboratory, Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Stathis Frillingos
- Laboratory of Biological Chemistry, Department of Medicine, University of Ioannina, Ioannina, Greece
| | - Emmanouil Flemetakis
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| |
Collapse
|
29
|
Wang Z, Wei X, Yang J, Li H, Ma B, Zhang K, Zhang Y, Cheng L, Ma F, Li M. Heterologous expression of the apple hexose transporter MdHT2.2 altered sugar concentration with increasing cell wall invertase activity in tomato fruit. PLANT BIOTECHNOLOGY JOURNAL 2020; 18:540-552. [PMID: 31350935 PMCID: PMC6953210 DOI: 10.1111/pbi.13222] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 07/17/2019] [Accepted: 07/19/2019] [Indexed: 05/08/2023]
Abstract
Sugar transporters are necessary to transfer hexose from cell wall spaces into parenchyma cells to boost hexose accumulation to high concentrations in fruit. Here, we have identified an apple hexose transporter (HTs), MdHT2.2, located in the plasma membrane, which is highly expressed in mature fruit. In a yeast system, the MdHT2.2 protein exhibited high 14 C-fructose and 14 C-glucose transport activity. In transgenic tomato heterologously expressing MdHT2.2, the levels of both fructose and glucose increased significantly in mature fruit, with sugar being unloaded via the apoplastic pathway, but the level of sucrose decreased significantly. Analysis of enzyme activity and the expression of genes related to sugar metabolism and transport revealed greatly up-regulated expression of SlLIN5, a key gene encoding cell wall invertase (CWINV), as well as increased CWINV activity in tomatoes transformed with MdHT2.2. Moreover, the levels of fructose, glucose and sucrose recovered nearly to those of the wild type in the sllin5-edited mutant of the MdHT2.2-expressing lines. However, the overexpression of MdHT2.2 decreased hexose levels and increased sucrose levels in mature leaves and young fruit, suggesting that the response pathway for the apoplastic hexose signal differs among tomato tissues. The present study identifies a new HTs in apple that is able to take up fructose and glucose into cells and confirms that the apoplastic hexose levels regulated by HT controls CWINV activity to alter carbohydrate partitioning and sugar content.
Collapse
Affiliation(s)
- Zhengyang Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Xiaoyu Wei
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Jingjing Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Huixia Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Baiquan Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Kaikai Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Yanfeng Zhang
- Hybrid Rape Research Center of Shaanxi ProvinceYanglingChina
| | - Lailiang Cheng
- Section of HorticultureSchool of Integrative Plant ScienceCornell UniversityIthacaNYUSA
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Mingjun Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| |
Collapse
|
30
|
Li C, Meng D, Piñeros MA, Mao Y, Dandekar AM, Cheng L. A Sugar Transporter Takes Up both Hexose and Sucrose for Sorbitol-Modulated In Vitro Pollen Tube Growth in Apple. THE PLANT CELL 2020; 32:449-469. [PMID: 31826966 PMCID: PMC7008483 DOI: 10.1105/tpc.19.00638] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/18/2019] [Accepted: 12/05/2019] [Indexed: 05/20/2023]
Abstract
Rapid pollen tube growth requires uptake of Suc or its hydrolytic products, hexoses, from the apoplast of surrounding tissues in the style. Due to species-specific sugar requirements, reliance of pollen germination and tube growth on cell wall invertase and Suc or hexose transporters varies between species, but it is not known if plants have a sugar transporter that mediates the uptake of both hexose and Suc for pollen tube growth. Here, we show that a sugar transporter protein in apple (Malus domestica), MdSTP13a, takes up both hexose and Suc when expressed in yeast, and is essential for pollen tube growth on Glc and Suc but not on maltose. MdSTP13a-mediated direct uptake of Suc is primarily responsible for apple pollen tube growth on Suc medium. Sorbitol, a major photosynthate and transport carbohydrate in apple, modulates pollen tube growth via the MYB transcription factor MdMYB39L, which binds to the promoter of MdSTP13a to activate its expression. Antisense repression of MdSTP13a blocks sorbitol-modulated pollen tube growth. These findings demonstrate that MdSTP13a takes up both hexose and Suc for sorbitol-modulated pollen tube growth in apple, revealing a situation where acquisition of sugars for pollen tube growth is regulated by a sugar alcohol.
Collapse
Affiliation(s)
- Chunlong Li
- Section of Horticulture, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853
| | - Dong Meng
- Section of Horticulture, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083 China
| | - Miguel A Piñeros
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture, Agricultural Research Service, Cornell University, Ithaca, New York 14853
| | - Yuxin Mao
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853
| | - Abhaya M Dandekar
- Department of Plant Sciences, University of California-Davis, Davis, California 95616
| | - Lailiang Cheng
- Section of Horticulture, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853
| |
Collapse
|
31
|
Impe D, Reitz J, Köpnick C, Rolletschek H, Börner A, Senula A, Nagel M. Assessment of Pollen Viability for Wheat. FRONTIERS IN PLANT SCIENCE 2020; 10:1588. [PMID: 32038666 PMCID: PMC6987437 DOI: 10.3389/fpls.2019.01588] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/12/2019] [Indexed: 05/15/2023]
Abstract
Wheat sheds tricellular short-lived pollen at maturity. The identification of viable pollen required for high seed set is important for breeders and conservators. The present study aims to evaluate and improve pollen viability tests and to identify factors influencing viability of pollen. In fresh wheat pollen, sucrose was the most abundant soluble sugar (90%). Raffinose was present in minor amounts. However, the analyses of pollen tube growth on 112 liquid and 45 solid media revealed that solid medium with 594 mM raffinose, 0.81 mM H3BO3, 2.04 mM CaCl2 at pH5.8 showed highest pollen germination. Partly or complete substitution of raffinose by sucrose, maltose, or sorbitol reduced in vitro germination of the pollen assuming a higher metabolic efficiency or antioxidant activity of raffinose. In vitro pollen germination varied between 26 lines (P < 0.001); between winter (15.3 ± 8.5%) and spring types (30.2 ± 13.3%) and was highest for the spring wheat TRI 2443 (50.1 ± 20.0%). Alexander staining failed to discriminate between viable, fresh pollen, and non-viable pollen inactivated by ambient storage for >60 min. Viability of fresh wheat pollen assessed by fluorescein diacetate (FDA) staining and impedance flow (IF) cytometry was 79.2 ± 4.2% and 88.1 ± 2.7%, respectively; and, when non-viable, stored pollen was additionally tested, it correlated at r = 0.54 (P < 0.05) and r = 0.67 (P < 0.001) with in vitro germination, respectively. When fresh pollen was used to assess the pollen viability of 19 wheat, 25 rye, 11 barley, and 4 maize lines, correlations were absent and in vitro germination was lower for rye (11.7 ± 8.5%), barley (6.8 ± 4.3%), and maize (2.1 ± 1.8%) pollen compared to wheat. Concluding, FDA staining and IF cytometry are used for a range of pollen species, whereas media for in vitro pollen germination require specific adaptations; in wheat, a solid medium with raffinose was chosen. On adapted media, the pollen tube growth can be exactly analyzed whereas results achieved by FDA staining and IF cytometry are higher and may overestimate pollen tube growth. Hence, as the exact viability and fertilization potential of a larger pollen batch remains elusive, a combination of pollen viability tests may provide reasonable indications of the ability of pollen to germinate and grow.
Collapse
Affiliation(s)
- Daniela Impe
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Janka Reitz
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Claudia Köpnick
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Hardy Rolletschek
- Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Andreas Börner
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Angelika Senula
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Manuela Nagel
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| |
Collapse
|
32
|
Cheng J, Wen S, Bie Z. Overexpression of hexose transporter CsHT3 increases cellulose content in cucumber fruit peduncle. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 145:107-113. [PMID: 31677541 DOI: 10.1016/j.plaphy.2019.10.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/01/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
Hexose transporters play many important roles in plant development. However, the role of hexose transporter in secondary cell wall growth has not been reported before. Here, we report that the hexose transporter gene CsHT3 is mainly expressed in cells with secondary cell walls in cucumber. Spatiotemporal expression analysis revealed that the transcript of CsHT3 mainly accumulates in the stem, petiole, tendril, and peduncle, all of which contain high cellulose levels. Immunolocalization results show that CsHT3 is localized at the sclereids in young peduncles, shifts to the phloem fiber cells during peduncle development, and then shifts again to the companion cells when the development of secondary cell walls is almost completed. Carboxyfluoresce unloading experiment indicated that carbohydrate unloading in the phloem follows an apoplastic pathway. Overexpression of CsHT3 in cucumber plant can improve the cellulose content and cell wall thickness of phloem fiber cells in the peduncle. The expression of cellulose synthase genes were increased in the CsHT3 overexpression plants. These results indicated that CsHT3 may play an important role in cellulose synthesis through promoting the expression of cellulose synthase genes.
Collapse
Affiliation(s)
- Jintao Cheng
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
| | - Suying Wen
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
| | - Zhilong Bie
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
| |
Collapse
|
33
|
Niño-González M, Novo-Uzal E, Richardson DN, Barros PM, Duque P. More Transporters, More Substrates: The Arabidopsis Major Facilitator Superfamily Revisited. MOLECULAR PLANT 2019; 12:1182-1202. [PMID: 31330327 DOI: 10.1016/j.molp.2019.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 05/20/2023]
Abstract
The Major Facilitator Superfamily (MFS) is ubiquitous in living organisms and represents the largest group of secondary active membrane transporters. In plants, significant research efforts have focused on the role of specific families within the MFS, particularly those transporting macronutrients (C, N, and P) that constitute the vast majority of the members of this superfamily. Other MFS families remain less explored, although a plethora of additional substrates and physiological functions have been uncovered. Nevertheless, the lack of a systematic approach to analyzing the MFS as a whole has obscured the high diversity and versatility of these transporters. Here, we present a phylogenetic analysis of all annotated MFS domain-containing proteins encoded in the Arabidopsis thaliana genome and propose that this superfamily of transporters consists of 218 members, clustered in 22 families. In reviewing the available information regarding the diversity in biological functions and substrates of Arabidopsis MFS members, we provide arguments for intensified research on these membrane transporters to unveil the breadth of their physiological relevance, disclose the molecular mechanisms underlying their mode of action, and explore their biotechnological potential.
Collapse
Affiliation(s)
| | | | | | - Pedro M Barros
- Genomics of Plant Stress Unit, ITQB NOVA - Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal
| | - Paula Duque
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal.
| |
Collapse
|
34
|
Brost C, Studtrucker T, Reimann R, Denninger P, Czekalla J, Krebs M, Fabry B, Schumacher K, Grossmann G, Dietrich P. Multiple cyclic nucleotide-gated channels coordinate calcium oscillations and polar growth of root hairs. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:910-923. [PMID: 31033043 DOI: 10.1111/tpj.14371] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 01/18/2019] [Accepted: 04/08/2019] [Indexed: 05/04/2023]
Abstract
Calcium gradients underlie polarization in eukaryotic cells. In plants, a tip-focused Ca2+ -gradient is fundamental for rapid and unidirectional cell expansion during epidermal root hair development. Here we report that three members of the cyclic nucleotide-gated channel family are required to maintain cytosolic Ca2+ oscillations and the normal growth of root hairs. CNGC6, CNGC9 and CNGC14 were expressed in root hairs, with CNGC9 displaying the highest root hair specificity. In individual channel mutants, morphological defects including root hair swelling and branching, as well as bursting, were observed. The developmental phenotypes were amplified in the three cngc double mutant combinations. Finally, cngc6/9/14 triple mutants only developed bulging trichoblasts and could not form normal root hair protrusions because they burst after the transition to the rapid growth phase. Prior to developmental defects, single and double mutants showed increasingly disturbed patterns of Ca2+ oscillations. We conclude that CNGC6, CNGC9 and CNGC14 fulfill partially but not fully redundant functions in generating and maintaining tip-focused Ca2+ oscillations, which are fundamental for proper root hair growth and polarity. Furthermore, the results suggest that these calmodulin-binding and Ca2+ -permeable channels organize a robust tip-focused oscillatory calcium gradient, which is not essential for root hair initiation but is required to control the integrity of the root hair after the transition to the rapid growth phase. Our findings also show that root hairs possess a large ability to compensate calcium-signaling defects, and add new players to the regulatory network, which coordinates cell wall properties and cell expansion during polar root hair growth.
Collapse
Affiliation(s)
- Christa Brost
- Molecular Plant Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Tanja Studtrucker
- Molecular Plant Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Ronny Reimann
- Molecular Plant Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Philipp Denninger
- CellNetworks Cluster of Excellence and Centre for Organismal Studies, Universität Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Jennifer Czekalla
- Molecular Plant Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Melanie Krebs
- Plant Developmental Biology, Centre for Organismal Studies, Universität Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Ben Fabry
- Department of Physics, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 91, 91052, Erlangen, Germany
| | - Karin Schumacher
- Plant Developmental Biology, Centre for Organismal Studies, Universität Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Guido Grossmann
- CellNetworks Cluster of Excellence and Centre for Organismal Studies, Universität Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Petra Dietrich
- Molecular Plant Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, 91058, Erlangen, Germany
| |
Collapse
|
35
|
Wang P, Wei P, Niu F, Liu X, Zhang H, Lyu M, Yuan Y, Wu B. Cloning and Functional Assessments of Floral-Expressed SWEET Transporter Genes from Jasminum sambac. Int J Mol Sci 2019; 20:ijms20164001. [PMID: 31426432 PMCID: PMC6719010 DOI: 10.3390/ijms20164001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/12/2019] [Accepted: 08/14/2019] [Indexed: 01/04/2023] Open
Abstract
Sugar transporters of the SWEET family mediate cross membrane movement of mono- and disaccharides and play vital roles in diverse physiological and pathophysiological processes, including sink-source relationship, pathogen responses, reproductive growth, and development. However, it remains to be determined how these transporters function in non-module plants of agricultural significance, given the evolutionarily diverse traits. In this study, we combined transcriptome analysis, rapid amplification of cDNA ends-cloning (RACE-cloning), expression profiling, and heterologous functional assay to identify SWEET genes that may have potential roles during flower opening and sexual reproduction in Jasminum sambac . During the anthesis, the floral organs of J. sambac express seven SWEET homologous genes from all four clades of the family. JsSWEET9 and 2 are significantly upregulated when flowers are fully opened, up to 6- and 3-fold compared to unopened buds, respectively. The other transporters, JsSWEET1, 5, 10, and 17 are also accumulated slightly at stage associated with fragrance release, whereas only the vacuole transporter JsSWEET16 showed small decrease in transcript level after anthesis. The JsSWEET5, a clade II member, is capable to complement yeast cell uptake on most tested sugar substrates with a preference for hexoses, while the clade I transporter JsSWEET1 mediates merely galactose import when expressed in yeast. Our results provide first evidence for further investigation on sugar transport and allocation during flowering and reproductive processes in J. sambac.
Collapse
Affiliation(s)
- Panpan Wang
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Peining Wei
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Fangfei Niu
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Xiaofeng Liu
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Hongliang Zhang
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Meiling Lyu
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Yuan Yuan
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China
| | - Binghua Wu
- Fujian Provincial Key Laboratory of Plant Functional Biology, College of Horticulture, Fujian A & University, Fuzhou 350002, China.
| |
Collapse
|
36
|
He C, Chen J, Wang H, Wan Y, Zhou J, Dan Z, Zeng Y, Xu W, Zhu Y, Huang W, Yin L. Crystal structures of rice hexokinase 6 with a series of substrates shed light on its enzymatic mechanism. Biochem Biophys Res Commun 2019; 515:614-620. [PMID: 31176485 DOI: 10.1016/j.bbrc.2019.05.139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 05/22/2019] [Indexed: 11/29/2022]
Abstract
Hexokinases (HXKs) have determined to be multifaceted proteins, and they are the only ones able to phosphorylate glucose in plants. However, the binding mode for ATP to plant HXKs remains unclear. Here, we report the crystal structures of rice hexokinase 6 (OsHXK6) in four different forms: (i) apo-form, (ii) binary complex with D-Glc, (iii) quaternary complex with ADP, PO4 and Mg2+, and (iv) pentanary complex with D-Glc, ADP, PO4, and Mg2+. The apo form is in the open state conformation, and the three others are in the closed state, indicating that glucose and ADP-PO4 binding induces a large conformational change by domain rearrangement. The quaternary complex is a novel intermediate during the catalytic reaction we trapped for the first time, which provides a new evidence for the enzymatic mechanism of HXKs. In addition, the latter two complexes reveal the binding mode for ADP-PO4 to plant HXKs, which provide the structural explanation for the dual-function of OsHXK6. In addition, we identified that residues Gly112, Thr261, Gly262, and Gly450 are essential to the binding between ADP-PO4 and OsHXK6 by a series of single mutations and enzymatic assays. Our study provide structural basis for the other functional studies of OsHXK6 in rice.
Collapse
Affiliation(s)
- Chunlan He
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Juan Chen
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Hongjian Wang
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, Department of Biochemistry and Molecular Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yibin Wan
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, Department of Biochemistry and Molecular Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jin Zhou
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, Department of Biochemistry and Molecular Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Zhiwu Dan
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Yafei Zeng
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Wuwu Xu
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Yingguo Zhu
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China
| | - Wenchao Huang
- State Key Laboratory of Hybrid Rice, Key Laboratory for Research and Utilization of Heterosis in Indica Rice, The Ministry of Agriculture, Wuhan University, Wuhan, 430072, China.
| | - Lei Yin
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, Department of Biochemistry and Molecular Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| |
Collapse
|
37
|
Sun L, Sui X, Lucas WJ, Li Y, Feng S, Ma S, Fan J, Gao L, Zhang Z. Down-regulation of the Sucrose Transporter CsSUT1 Causes Male Sterility by Altering Carbohydrate Supply. PLANT PHYSIOLOGY 2019; 180:986-997. [PMID: 30967482 PMCID: PMC6548282 DOI: 10.1104/pp.19.00317] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 03/27/2019] [Indexed: 05/20/2023]
Abstract
In plants, male sterility is an important agronomic trait, especially in hybrid crop production. Many factors are known to affect crop male sterility, but it remains unclear whether Suc transporters (SUTs) participate directly in this process. Here, we identified and functionally characterized the cucumber (Cucumis sativus) CsSUT1, a typical plasma membrane-localized energy-dependent high-affinity Suc-H+ symporter. CsSUT1 is expressed in male flowers and encodes a protein that is localized primarily in the tapetum, pollen, and companion cells of the phloem of sepals, petals, filaments, and pedicel. The male flowers of CsSUT1-RNA interference (RNAi) lines exhibited a decrease in Suc, hexose, and starch content, relative to those of the wild type, during the later stages of male flower development, a finding that was highly associated with male sterility. Transcriptomic analysis revealed that numerous genes associated with sugar metabolism, transport, and signaling, as well as with auxin signaling, were down-regulated, whereas most myeloblastosis (MYB) transcription factor genes were up-regulated in these CsSUT1-RNAi lines relative to wild type. Our findings demonstrate that male sterility can be induced by RNAi-mediated down-regulation of CsSUT1 expression, through the resultant perturbation in carbohydrate delivery and subsequent alteration in sugar and hormone signaling and up-regulation of specific MYB transcription factors. This knowledge provides a new approach for bioengineering male sterility in crop plants.
Collapse
Affiliation(s)
- Lulu Sun
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Xiaolei Sui
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - William J Lucas
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, California 95616
| | - Yaxin Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Sheng Feng
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Si Ma
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Jingwei Fan
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Lihong Gao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Zhenxian Zhang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| |
Collapse
|
38
|
Shen S, Ma S, Liu Y, Liao S, Li J, Wu L, Kartika D, Mock HP, Ruan YL. Cell Wall Invertase and Sugar Transporters Are Differentially Activated in Tomato Styles and Ovaries During Pollination and Fertilization. FRONTIERS IN PLANT SCIENCE 2019; 10:506. [PMID: 31057596 PMCID: PMC6482350 DOI: 10.3389/fpls.2019.00506] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/02/2019] [Indexed: 05/05/2023]
Abstract
Flowering plants depend on pollination and fertilization to activate the transition from ovule to seed and ovary to fruit, namely seed and fruit set, which are key for completing the plant life cycle and realizing crop yield potential. These processes are highly energy consuming and rely on the efficient use of sucrose as the major nutrient and energy source. However, it remains elusive as how sucrose imported into and utilizated within the female reproductive organ is regulated in response to pollination and fertilization. Here, we explored this issue in tomato by focusing on genes encoding cell wall invertase (CWIN) and sugar transporters, which are major players in sucrose phloem unloading, and sink development. The transcript level of a major CWIN gene, LIN5, and CWIN activity were significantly increased in style at 4 h after pollination (HAP) in comparison with that in the non-pollination control, and this was sustained at 2 days after pollination (DAP). In the ovaries, however, CWIN activity and LIN5 expression did not increase until 2 DAP when fertilization occurred. Interestingly, a CWIN inhibitor gene INVINH1 was repressed in the pollinated style at 2 DAP. In response to pollination, the style exhibited increased expressions of genes encoding hexose transporters, SlHT1, 2, SlSWEET5b, and sucrose transporters SlSUT1, 2, and 4 from 4 HAP to 2 DAP. Upon fertilization, SlSUT1 and SlHT1 and 2, but not SlSWEETs, were also stimulated in fruitlets at 2 DAP. Together, the findings reveal that styles respond promptly and more broadly to pollination for activation of CWIN and sugar transporters to fuel pollen tube elongation, whereas the ovaries do not exhibit activation for some of these genes until fertilization occurs. HIGHLIGHTS Expression of genes encoding cell wall invertases and sugar transporters was stimulated in pollinated style and fertilized ovaries in tomato.
Collapse
Affiliation(s)
- Si Shen
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Si Ma
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Yonghua Liu
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Shengjin Liao
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Jun Li
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Limin Wu
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Dewi Kartika
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Hans-Peter Mock
- Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Yong-Ling Ruan
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| |
Collapse
|
39
|
Paulsen PA, Custódio TF, Pedersen BP. Crystal structure of the plant symporter STP10 illuminates sugar uptake mechanism in monosaccharide transporter superfamily. Nat Commun 2019; 10:407. [PMID: 30679446 PMCID: PMC6345825 DOI: 10.1038/s41467-018-08176-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/19/2018] [Indexed: 01/06/2023] Open
Abstract
Plants are dependent on controlled sugar uptake for correct organ development and sugar storage, and apoplastic sugar depletion is a defense strategy against microbial infections like rust and mildew. Uptake of glucose and other monosaccharides is mediated by Sugar Transport Proteins, proton-coupled symporters from the Monosaccharide Transporter (MST) superfamily. We present the 2.4 Å structure of Arabidopsis thaliana high affinity sugar transport protein, STP10, with glucose bound. The structure explains high affinity sugar recognition and suggests a proton donor/acceptor pair that links sugar transport to proton translocation. It contains a Lid domain, conserved in all STPs, that locks the mobile transmembrane domains through a disulfide bridge, and creates a protected environment which allows efficient coupling of the proton gradient to drive sugar uptake. The STP10 structure illuminates fundamental principles of sugar transport in the MST superfamily with implications for both plant antimicrobial defense, organ development and sugar storage.
Collapse
Affiliation(s)
- Peter Aasted Paulsen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10, DK-8000, Aarhus C, Denmark
| | - Tânia F Custódio
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10, DK-8000, Aarhus C, Denmark
| | - Bjørn Panyella Pedersen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10, DK-8000, Aarhus C, Denmark.
- Aarhus Institute of Advanced Studies, Aarhus University, Høegh-Guldbergs Gade 6B, DK-8000, Aarhus C, Denmark.
| |
Collapse
|
40
|
Strobl SM, Kischka D, Heilmann I, Mouille G, Schneider S. The Tonoplastic Inositol Transporter INT1 From Arabidopsis thaliana Impacts Cell Elongation in a Sucrose-Dependent Way. FRONTIERS IN PLANT SCIENCE 2018; 9:1657. [PMID: 30505313 PMCID: PMC6250803 DOI: 10.3389/fpls.2018.01657] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 10/25/2018] [Indexed: 05/29/2023]
Abstract
The tonoplastic inositol transporter INT1 is the only known transport protein in Arabidopsis that facilitates myo-inositol import from the vacuole into the cytoplasm. Impairment of the release of vacuolar inositol by knockout of INT1 results in a severe inhibition of cell elongation in roots as well as in etiolated hypocotyls. Importantly, a more strongly reduced cell elongation was observed when sucrose was supplied in the growth medium, and this sucrose-dependent effect can be complemented by the addition of exogenous myo-inositol. Comparing int1 mutants (defective in transport) with mutants defective in myo-inositol biosynthesis (mips1 mutants) revealed that the sucrose-induced inhibition in cell elongation does not just depend on inositol depletion. Secondary effects as observed for altered availability of inositol in biosynthesis mutants, as disturbed membrane turnover, alterations in PIN protein localization or alterations in inositol-derived signaling molecules could be ruled out to be responsible for impairing the cell elongation in int1 mutants. Although the molecular mechanism remains to be elucidated, our data implicate a crucial role of INT1-transported myo-inositol in regulating cell elongation in a sucrose-dependent manner and underline recent reports of regulatory roles for sucrose and other carbohydrate intermediates as metabolic semaphores.
Collapse
Affiliation(s)
- Sabrina Maria Strobl
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Dominik Kischka
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Ingo Heilmann
- Department of Cellular Biochemistry, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Grégory Mouille
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris Saclay, Versailles, France
| | - Sabine Schneider
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
41
|
Jegadeesan S, Chaturvedi P, Ghatak A, Pressman E, Meir S, Faigenboim A, Rutley N, Beery A, Harel A, Weckwerth W, Firon N. Proteomics of Heat-Stress and Ethylene-Mediated Thermotolerance Mechanisms in Tomato Pollen Grains. FRONTIERS IN PLANT SCIENCE 2018; 9:1558. [PMID: 30483278 PMCID: PMC6240657 DOI: 10.3389/fpls.2018.01558] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/04/2018] [Indexed: 05/19/2023]
Abstract
Heat stress is a major cause for yield loss in many crops, including vegetable crops. Even short waves of high temperature, becoming more frequent during recent years, can be detrimental. Pollen development is most heat-sensitive, being the main cause for reduced productivity under heat-stress across a wide range of crops. The molecular mechanisms involved in pollen heat-stress response and thermotolerance are however, not fully understood. Recently, we have demonstrated that ethylene, a gaseous plant hormone, plays a role in tomato (Solanum lycopersicum) pollen thermotolerance. These results were substantiated in the current work showing that increasing ethylene levels by using an ethylene-releasing substance, ethephon, prior to heat-stress exposure, increased pollen quality. A proteomic approach was undertaken, to unravel the mechanisms underlying pollen heat-stress response and ethylene-mediated pollen thermotolerance in developing pollen grains. Proteins were extracted and analyzed by means of a gel LC-MS fractionation protocol, and a total of 1,355 proteins were identified. A dataset of 721 proteins, detected in three biological replicates of at least one of the applied treatments, was used for all analyses. Quantitative analysis was performed based on peptide count. The analysis revealed that heat-stress affected the developmental program of pollen, including protein homeostasis (components of the translational and degradation machinery), carbohydrate, and energy metabolism. Ethephon-pre-treatment shifted the heat-stressed pollen proteome closer to the proteome under non-stressful conditions, namely, by showing higher abundance of proteins involved in protein synthesis, degradation, tricarboxylic acid cycle, and RNA regulation. Furthermore, up-regulation of protective mechanisms against oxidative stress was observed following ethephon-treatment (including higher abundance of glutathione-disulfide reductase, glutaredoxin, and protein disulfide isomerase). Taken together, the findings identified systemic and fundamental components of pollen thermotolerance, and serve as a valuable quantitative protein database for further research.
Collapse
Affiliation(s)
- Sridharan Jegadeesan
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
- The Robert H. Smith Faculty of Agriculture, Food and Environment, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture of The Hebrew University of Jerusalem, Rehovot, Israel
| | - Palak Chaturvedi
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Vienna Metabolomics Center, University of Vienna, Vienna, Austria
| | - Arindam Ghatak
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Vienna Metabolomics Center, University of Vienna, Vienna, Austria
| | - Etan Pressman
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Shimon Meir
- Institute of Postharvest and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Adi Faigenboim
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Nicholas Rutley
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Avital Beery
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Arye Harel
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Wolfram Weckwerth
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Vienna Metabolomics Center, University of Vienna, Vienna, Austria
| | - Nurit Firon
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| |
Collapse
|
42
|
Rottmann T, Fritz C, Sauer N, Stadler R. Glucose Uptake via STP Transporters Inhibits in Vitro Pollen Tube Growth in a HEXOKINASE1-Dependent Manner in Arabidopsis thaliana. THE PLANT CELL 2018; 30:2057-2081. [PMID: 30120167 PMCID: PMC6181011 DOI: 10.1105/tpc.18.00356] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/10/2018] [Accepted: 08/13/2018] [Indexed: 05/07/2023]
Abstract
Pollen tube growth requires a high amount of metabolic energy and precise targeting toward the ovules. Sugars, especially glucose, can serve as nutrients and as signaling molecules. Unexpectedly, in vitro assays revealed an inhibitory effect of glucose on pollen tube elongation, contradicting the hypothesis that monosaccharide uptake is a source of nutrition for growing pollen tubes. Measurements with Förster resonance energy transfer-based nanosensors revealed that glucose is taken up into pollen tubes and that the intracellular concentration is in the low micromolar range. Pollen tubes of stp4-6-8-9-10-11 sextuple knockout plants generated by crossings and CRISPR/Cas9 showed only a weak response to glucose, indicating that glucose uptake into pollen tubes is mediated mainly by these six monosaccharide transporters of the SUGAR TRANSPORT PROTEIN (STP) family. Analyses of HEXOKINASE1 (HXK1) showed a strong expression of this gene in pollen. Together with the glucose insensitivity and altered semi-in vivo growth rate of pollen tubes from hxk1 knockout lines, this strongly suggests that glucose is an important signaling molecule for pollen tubes, is taken up by STPs, and detected by HXK1. Equimolar amounts of fructose abolish the inhibitory effect of glucose indicating that only an excess of glucose is interpreted as a signal. This provides a possible model for the discrimination of signaling and nutritional sugars.
Collapse
Affiliation(s)
- Theresa Rottmann
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Carolin Fritz
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Norbert Sauer
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Ruth Stadler
- Molecular Plant Physiology, Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| |
Collapse
|
43
|
Sakr S, Wang M, Dédaldéchamp F, Perez-Garcia MD, Ogé L, Hamama L, Atanassova R. The Sugar-Signaling Hub: Overview of Regulators and Interaction with the Hormonal and Metabolic Network. Int J Mol Sci 2018; 57:2367-2379. [PMID: 30149541 DOI: 10.1093/pcp/pcw157] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/07/2018] [Accepted: 09/05/2016] [Indexed: 05/25/2023] Open
Abstract
Plant growth and development has to be continuously adjusted to the available resources. Their optimization requires the integration of signals conveying the plant metabolic status, its hormonal balance, and its developmental stage. Many investigations have recently been conducted to provide insights into sugar signaling and its interplay with hormones and nitrogen in the fine-tuning of plant growth, development, and survival. The present review emphasizes the diversity of sugar signaling integrators, the main molecular and biochemical mechanisms related to the sugar-signaling dependent regulations, and to the regulatory hubs acting in the interplay of the sugar-hormone and sugar-nitrogen networks. It also contributes to compiling evidence likely to fill a few knowledge gaps, and raises new questions for the future.
Collapse
Affiliation(s)
- Soulaiman Sakr
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Ming Wang
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Fabienne Dédaldéchamp
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| | - Maria-Dolores Perez-Garcia
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Laurent Ogé
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Latifa Hamama
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Rossitza Atanassova
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| |
Collapse
|
44
|
Sakr S, Wang M, Dédaldéchamp F, Perez-Garcia MD, Ogé L, Hamama L, Atanassova R. The Sugar-Signaling Hub: Overview of Regulators and Interaction with the Hormonal and Metabolic Network. Int J Mol Sci 2018; 19:ijms19092506. [PMID: 30149541 PMCID: PMC6165531 DOI: 10.3390/ijms19092506] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 08/07/2018] [Accepted: 08/13/2018] [Indexed: 12/31/2022] Open
Abstract
Plant growth and development has to be continuously adjusted to the available resources. Their optimization requires the integration of signals conveying the plant metabolic status, its hormonal balance, and its developmental stage. Many investigations have recently been conducted to provide insights into sugar signaling and its interplay with hormones and nitrogen in the fine-tuning of plant growth, development, and survival. The present review emphasizes the diversity of sugar signaling integrators, the main molecular and biochemical mechanisms related to the sugar-signaling dependent regulations, and to the regulatory hubs acting in the interplay of the sugar-hormone and sugar-nitrogen networks. It also contributes to compiling evidence likely to fill a few knowledge gaps, and raises new questions for the future.
Collapse
Affiliation(s)
- Soulaiman Sakr
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Ming Wang
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Fabienne Dédaldéchamp
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| | - Maria-Dolores Perez-Garcia
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Laurent Ogé
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Latifa Hamama
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Rossitza Atanassova
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| |
Collapse
|
45
|
Dickinson H, Rodriguez-Enriquez J, Grant-Downton R. Pollen Germination and Pollen Tube Growth of Arabidopsis thaliana: in vitro and Semi in vivo Methods. Bio Protoc 2018; 8:e2977. [PMID: 34395777 DOI: 10.21769/bioprotoc.2977] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 07/31/2018] [Accepted: 08/03/2018] [Indexed: 11/02/2022] Open
Abstract
Studies of pollen germination and post-germination development are not only essential for understanding plant reproduction but also are an excellent model system for tip-based growth. Here we describe easy, reproducible methods for germination and growth of pollen from the model plant Arabidopsis thaliana in artificial conditions. Our growth system can be used both for pollen placed directly on this artificial substrate as well as for the so-called 'semi in vivo' method. This is where a pistil is cut shortly after hand-pollination and the pollen tubes grow through the plant tissue and emerge from the cut end onto the surface of the artificial medium.
Collapse
Affiliation(s)
- Hugh Dickinson
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
| | - Josefina Rodriguez-Enriquez
- Instituto Universitario de Bio-Orgánica "Antonio González" (IUBO), Universidad de La Laguna (ULL), San Cristóbal de La Laguna, Spain
| | | |
Collapse
|
46
|
Müdsam C, Wollschläger P, Sauer N, Schneider S. Sorting of Arabidopsis NRAMP3 and NRAMP4 depends on adaptor protein complex AP4 and a dileucine-based motif. Traffic 2018; 19:503-521. [PMID: 29573093 DOI: 10.1111/tra.12567] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 03/14/2018] [Accepted: 03/16/2018] [Indexed: 01/01/2023]
Abstract
Adaptor protein complexes mediate cargo selection and vesicle trafficking to different cellular membranes in all eukaryotic cells. Information on the role of AP4 in plants is still limited. Here, we present the analyses of Arabidopsis thaliana mutants lacking different subunits of AP4. These mutants show abnormalities in their development and in protein sorting. We found that growth of roots and etiolated hypocotyls, as well as male fertility and trichome morphology are disturbed in ap4. Analyses of GFP-fusions transiently expressed in mesophyll protoplasts demonstrated that the tonoplast (TP) proteins MOT2, NRAMP3 and NRAMP4, but not INT1, are partially sorted to the plasma membrane (PM) in the absence of a functional AP4 complex. Moreover, alanine mutagenesis revealed that in wild-type plants, sorting of NRAMP3 and NRAMP4 to the TP requires an N-terminal dileucine-based motif. The NRAMP3 or NRAMP4 N-terminal domain containing the dileucine motif was sufficient to redirect the PM localized INT4 protein to the TP and to confer AP4-dependency on sorting of INT1. Our data show that correct sorting of NRAMP3 and NRAMP4 depends on both, an N-terminal dileucine-based motif as well as AP4.
Collapse
Affiliation(s)
- Christina Müdsam
- Molecular Plant Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Paul Wollschläger
- Molecular Plant Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Norbert Sauer
- Molecular Plant Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Sabine Schneider
- Molecular Plant Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| |
Collapse
|
47
|
Rottmann T, Klebl F, Schneider S, Kischka D, Rüscher D, Sauer N, Stadler R. Sugar Transporter STP7 Specificity for l-Arabinose and d-Xylose Contrasts with the Typical Hexose Transporters STP8 and STP12. PLANT PHYSIOLOGY 2018; 176:2330-2350. [PMID: 29311272 PMCID: PMC5841717 DOI: 10.1104/pp.17.01493] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 12/29/2017] [Indexed: 05/08/2023]
Abstract
The controlled distribution of sugars between assimilate-exporting source tissues and sugar-consuming sink tissues is a key element for plant growth and development. Monosaccharide transporters of the SUGAR TRANSPORT PROTEIN (STP) family contribute to the uptake of sugars into sink cells. Here, we report on the characterization of STP7, STP8, and STP12, three previously uncharacterized members of this family in Arabidopsis (Arabidopsis thaliana). Heterologous expression in yeast (Saccharomyces cerevisiae) revealed that STP8 and STP12 catalyze the high-affinity proton-dependent uptake of glucose and also accept galactose and mannose. STP12 additionally transports xylose. STP8 and STP12 are highly expressed in reproductive organs, where their protein products might contribute to sugar uptake into the pollen tube and the embryo sac. stp8.1 and stp12.1 T-DNA insertion lines developed normally, which may point toward functional redundancy with other STPs. In contrast to all other STPs, STP7 does not transport hexoses but is specific for the pentoses l-arabinose and d-xylose. STP7-promoter-reporter gene plants showed an expression of STP7 especially in tissues with high cell wall turnover, indicating that STP7 might contribute to the uptake and recycling of cell wall sugars. Uptake analyses with radioactive l-arabinose revealed that 11 other STPs are able to transport l-arabinose with high affinity. Hence, functional redundancy might explain the missing-mutant phenotype of two stp7 T-DNA insertion lines. Together, these data complete the characterization of the STP family and present the STPs as new l-arabinose transporters for potential biotechnological applications.
Collapse
Affiliation(s)
- Theresa Rottmann
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Franz Klebl
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Sabine Schneider
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Dominik Kischka
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - David Rüscher
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Norbert Sauer
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Ruth Stadler
- Molecular Plant Physiology, University Erlangen-Nürnberg, 91058 Erlangen, Germany
| |
Collapse
|
48
|
Barnes WJ, Anderson CT. Release, Recycle, Rebuild: Cell-Wall Remodeling, Autodegradation, and Sugar Salvage for New Wall Biosynthesis during Plant Development. MOLECULAR PLANT 2018; 11:31-46. [PMID: 28859907 DOI: 10.1016/j.molp.2017.08.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/16/2017] [Accepted: 08/21/2017] [Indexed: 05/20/2023]
Abstract
Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by transglycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precursors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evidence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the developmental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.
Collapse
Affiliation(s)
- William J Barnes
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Charles T Anderson
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, PA 16802, USA.
| |
Collapse
|
49
|
Rottmann TM, Fritz C, Lauter A, Schneider S, Fischer C, Danzberger N, Dietrich P, Sauer N, Stadler R. Protoplast-Esculin Assay as a New Method to Assay Plant Sucrose Transporters: Characterization of AtSUC6 and AtSUC7 Sucrose Uptake Activity in Arabidopsis Col-0 Ecotype. FRONTIERS IN PLANT SCIENCE 2018; 9:430. [PMID: 29740457 PMCID: PMC5925572 DOI: 10.3389/fpls.2018.00430] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 03/20/2018] [Indexed: 05/20/2023]
Abstract
The best characterized function of sucrose transporters of the SUC family in plants is the uptake of sucrose into the phloem for long-distance transport of photoassimilates. This important step is usually performed by one specific SUC in every species. However, plants possess small families of several different SUCs which are less well understood. Here, we report on the characterization of AtSUC6 and AtSUC7, two members of the SUC family in Arabidopsis thaliana. Heterologous expression in yeast (Saccharomyces cerevisiae) revealed that AtSUC6Col-0 is a high-affinity H+-symporter that mediates the uptake of sucrose and maltose across the plasma membrane at exceptionally low pH values. Reporter gene analyses revealed a strong expression of AtSUC6Col-0 in reproductive tissues, where the protein product might contribute to sugar uptake into pollen tubes and synergid cells. A knockout of AtSUC6 did not interfere with vegetative development or reproduction, which points toward physiological redundancy of AtSUC6Col-0 with other sugar transporters. Reporter gene analyses showed that AtSUC7Col-0 is expressed in roots and pollen tubes and that this sink specific expression of AtSUC7Col-0 is regulated by intragenic regions. Transport activity of AtSUC7Col-0 could not be analyzed in baker's yeast or Xenopus oocytes because the protein was not correctly targeted to the plasma membrane in both heterologous expression systems. Therefore, a novel approach to analyze sucrose transporters in planta was developed. Plasma membrane localized SUCs including AtSUC6Col-0 and also sucrose specific SWEETs were able to mediate transport of the fluorescent sucrose analog esculin in transformed mesophyll protoplasts. In contrast, AtSUC7Col-0 is not able to mediate esculin transport across the plasma membrane which implicates that AtSUC7Col-0 might be a non-functional pseudogene. The novel protoplast assay provides a useful tool for the quick and quantitative analysis of sucrose transporters in an in planta expression system.
Collapse
|
50
|
Borghi M, Fernie AR. Floral Metabolism of Sugars and Amino Acids: Implications for Pollinators' Preferences and Seed and Fruit Set. PLANT PHYSIOLOGY 2017; 175:1510-1524. [PMID: 28986424 PMCID: PMC5717749 DOI: 10.1104/pp.17.01164] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 10/04/2017] [Indexed: 05/10/2023]
Abstract
New discoveries open up future directions in the study of the primary metabolism of flowers.
Collapse
Affiliation(s)
- Monica Borghi
- Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| |
Collapse
|