1
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Yang Y, Liu X, Wang X, Lv W, Liu X, Ma L, Fu H, Song S, Lei X. Screening of protonstatin-1 (PS-1) analogs for improved inhibitors of plant plasma membrane H +-ATPase activity. FRONTIERS IN PLANT SCIENCE 2022; 13:973471. [PMID: 36311099 PMCID: PMC9597486 DOI: 10.3389/fpls.2022.973471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
We previously identified protonstatin-1 (PS-1) as a selective inhibitor of plasma membrane H+-ATPase (PM H+-ATPase) activity and used it as a tool to validate the chemiosmotic model for polar auxin transport. Here, to obtain compounds with higher affinity than PS-1 for PM H+-ATPase, we synthesized 34 PS-1 analogs and examined their ability to inhibit PM H+-ATPase activity. The 34 analogs showed varying inhibitory effects on the activity of this enzyme. The strongest effect was observed for the small molecule PS-2, which was approximately five times stronger than PS-1. Compared to PS-1, PS-2 was also a stronger inhibitor of auxin uptake as well as acropetal and basipetal polar auxin transport in Arabidopsis thaliana seedlings. Because PS-2 is a more potent inhibitor of PM H+-ATPase than PS-1, we believe that this compound could be used as a tool to study the functions of this key plant enzyme.
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Affiliation(s)
- Yongqing Yang
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiaohui Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xin Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Wanjia Lv
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiao Liu
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Liang Ma
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Haiqi Fu
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Shu Song
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiaoguang Lei
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
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2
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Yang Y, Liu X, Guo W, Liu W, Shao W, Zhao J, Li J, Dong Q, Ma L, He Q, Li Y, Han J, Lei X. Testing the polar auxin transport model with a selective plasma membrane H + -ATPase inhibitor. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:1229-1245. [PMID: 35352470 DOI: 10.1111/jipb.13256] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 03/24/2022] [Indexed: 06/14/2023]
Abstract
Auxin is unique among plant hormones in that its function requires polarized transport across plant cells. A chemiosmotic model was proposed to explain how polar auxin transport is derived by the H+ gradient across the plasma membrane (PM) established by PM H+ -adenosine triphosphatases (ATPases). However, a classical genetic approach by mutations in PM H+ -ATPase members did not result in the ablation of polar auxin distribution, possibly due to functional redundancy in this gene family. To confirm the crucial role of PM H+ -ATPases in the polar auxin transport model, we employed a chemical genetic approach. Through a chemical screen, we identified protonstatin-1 (PS-1), a selective small-molecule inhibitor of PM H+ -ATPase activity that inhibits auxin transport. Assays with transgenic plants and yeast strains showed that the activity of PM H+ -ATPases affects auxin uptake as well as acropetal and basipetal polar auxin transport. We propose that PS-1 can be used as a tool to interrogate the function of PM H+ -ATPases. Our results support the chemiosmotic model in which PM H+ -ATPase itself plays a fundamental role in polar auxin transport.
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Affiliation(s)
- Yongqing Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaohui Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Wei Guo
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Wei Liu
- Department of Dermatology, Peking University First Hospital, Beijing, 100034, China
| | - Wei Shao
- Iomics Biosciences Inc., Beijing, 100102, China
| | - Jun Zhao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Junhong Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Qing Dong
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Liang Ma
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Qun He
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yingzhang Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Jianyong Han
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaoguang Lei
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
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3
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Bogaert KA, Blomme J, Beeckman T, De Clerck O. Auxin's origin: do PILS hold the key? TRENDS IN PLANT SCIENCE 2022; 27:227-236. [PMID: 34716098 DOI: 10.1016/j.tplants.2021.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 08/23/2021] [Accepted: 09/28/2021] [Indexed: 05/12/2023]
Abstract
Auxin is a key regulator of many developmental processes in land plants and plays a strikingly similar role in the phylogenetically distant brown seaweeds. Emerging evidence shows that the PIN and PIN-like (PILS) auxin transporter families have preceded the evolution of the canonical auxin response pathway. A wide conservation of PILS-mediated auxin transport, together with reports of auxin function in unicellular algae, would suggest that auxin function preceded the advent of multicellularity. We find that PIN and PILS transporters form two eukaryotic subfamilies within a larger bacterial family. We argue that future functional characterisation of algal PIN and PILS transporters can shed light on a common origin of an auxin function followed by independent co-option in a multicellular context.
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Affiliation(s)
- Kenny Arthur Bogaert
- Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium.
| | - Jonas Blomme
- Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center for Plant Systems Biology, VIB-UGent, Technologiepark 72, B-9052 Ghent, Belgium
| | - Tom Beeckman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center for Plant Systems Biology, VIB-UGent, Technologiepark 72, B-9052 Ghent, Belgium
| | - Olivier De Clerck
- Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
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4
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Sun C, Li D, Gao Z, Gao L, Shang L, Wang M, Qiao J, Ding S, Li C, Geisler M, Jiang D, Qi Y, Qian Q. OsRLR4 binds to the OsAUX1 promoter to negatively regulate primary root development in rice. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:118-134. [PMID: 34726825 DOI: 10.1111/jipb.13183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
Root architecture is one of the most important agronomic traits that determines rice crop yield. The primary root (PR) absorbs mineral nutrients and provides mechanical support; however, the molecular mechanisms of PR elongation remain unclear in rice. Here, the two loss-of-function T-DNA insertion mutants of root length regulator 4 (OsRLR4), osrlr4-1 and osrlr4-2 with longer PR, and three OsRLR4 overexpression lines, OE-OsRLR4-1/-2/-3 with shorter PR compared to the wild type/Hwayoung (WT/HY), were identified. OsRLR4 is one of five members of the PRAF subfamily of the regulator chromosome condensation 1 (RCC1) family. Phylogenetic analysis of OsRLR4 from wild and cultivated rice indicated that it is under selective sweeps, suggesting its potential role in domestication. OsRLR4 controls PR development by regulating auxin accumulation in the PR tip and thus the root apical meristem activity. A series of biochemical and genetic analyses demonstrated that OsRLR4 functions directly upstream of the auxin transporter OsAUX1. Moreover, OsRLR4 interacts with the TRITHORAX-like protein OsTrx1 to promote H3K4me3 deposition at the OsAUX1 promoter, thus altering its transcription level. This work provides insight into the cooperation of auxin and epigenetic modifications in regulating root architecture and provides a genetic resource for plant architecture breeding.
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Affiliation(s)
- Chendong Sun
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot, 010000, China
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang Agriculture and Forestry University, Lin'an Hangzhou, 311300, China
| | - Dongming Li
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot, 010000, China
| | - Zhenyu Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006, China
| | - Lei Gao
- College of Life Sciences and Oceanography, Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen University, Shenzhen, China
| | - Lianguang Shang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Mei Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jiyue Qiao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Shilin Ding
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006, China
| | - Chuanyou Li
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, The Chinese Academy of Sciences, Beijing, 100101, China
| | - Markus Geisler
- Department of Biology, University of Fribourg, Fribourg, CH-1700, Switzerland
| | - Dean Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yanhua Qi
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot, 010000, China
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006, China
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5
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Qiao J, Jiang H, Lin Y, Shang L, Wang M, Li D, Fu X, Geisler M, Qi Y, Gao Z, Qian Q. A novel miR167a-OsARF6-OsAUX3 module regulates grain length and weight in rice. MOLECULAR PLANT 2021; 14:1683-1698. [PMID: 34186219 DOI: 10.1016/j.molp.2021.06.023] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 05/26/2021] [Accepted: 06/25/2021] [Indexed: 05/02/2023]
Abstract
Grain size is one of the most important factors that control rice yield, as it is associated with grain weight (GW). To date, dozens of rice genes that regulate grain size have been isolated; however, the regulatory mechanism underlying GW control is not fully understood. Here, the quantitative trait locus qGL5 for grain length (GL) and GW was identified in recombinant inbred lines of 9311 and Nipponbare (NPB) and fine mapped to a candidate gene, OsAUX3. Sequence variations between 9311 and NPB in the OsAUX3 promoter and loss of function of OsAUX3 led to higher GL and GW. RNA sequencing, gene expression quantification, dual-luciferase reporter assays, chromatin immunoprecipitation-quantitative PCR, and yeast one-hybrid assays demonstrated that OsARF6 is an upstream transcription factor regulating the expression of OsAUX3. OsARF6 binds directly to the auxin response elements of the OsAUX3 promoter, covering a single-nucleotide polymorphism site between 9311 and NPB/Dongjin/Hwayoung, and thereby controls GL by altering longitudinal expansion and auxin distribution/content in glume cells. Furthermore, we showed that miR167a positively regulate GL and GW by directing OsARF6 mRNA silencing. Taken together, our study reveals that a novel miR167a-OsARF6-OsAUX3 module regulates GL and GW in rice, providing a potential target for the improvement of rice yield.
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Affiliation(s)
- Jiyue Qiao
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot 010000, China; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongzhen Jiang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China
| | - Yuqing Lin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lianguang Shang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Mei Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Dongming Li
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot 010000, China
| | - Xiangdong Fu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, University of Chinese Academy of Sciences, 100049, China
| | - Markus Geisler
- Department of Biology, University of Fribourg, Rue Albert-Gockel 3, CH-1700 Fribourg, Switzerland
| | - Yanhua Qi
- Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot 010000, China; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Zhenyu Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China.
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China; Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China.
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6
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Havukainen S, Pujol-Giménez J, Valkonen M, Westerholm-Parvinen A, Hediger MA, Landowski CP. Electrophysiological characterization of a diverse group of sugar transporters from Trichoderma reesei. Sci Rep 2021; 11:14678. [PMID: 34282161 PMCID: PMC8290022 DOI: 10.1038/s41598-021-93552-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/21/2021] [Indexed: 02/06/2023] Open
Abstract
Trichoderma reesei is an ascomycete fungus known for its capability to secrete high amounts of extracellular cellulose- and hemicellulose-degrading enzymes. These enzymes are utilized in the production of second-generation biofuels and T. reesei is a well-established host for their production. Although this species has gained considerable interest in the scientific literature, the sugar transportome of T. reesei remains poorly characterized. Better understanding of the proteins involved in the transport of different sugars could be utilized for engineering better enzyme production strains. In this study we aimed to shed light on this matter by characterizing multiple T. reesei transporters capable of transporting various types of sugars. We used phylogenetics to select transporters for expression in Xenopus laevis oocytes to screen for transport activities. Of the 18 tested transporters, 8 were found to be functional in oocytes. 10 transporters in total were investigated in oocytes and in yeast, and for 3 of them no transport function had been described in literature. This comprehensive analysis provides a large body of new knowledge about T. reesei sugar transporters, and further establishes X. laevis oocytes as a valuable tool for studying fungal sugar transporters.
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Affiliation(s)
- Sami Havukainen
- Protein Production Team, VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150, Espoo, Finland
| | - Jonai Pujol-Giménez
- Membrane Transport Discovery Lab, Department of Biomedical Research, Inselspital, University of Bern, 3010, Bern, Switzerland
| | - Mari Valkonen
- Protein Production Team, VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150, Espoo, Finland
| | - Ann Westerholm-Parvinen
- Protein Production Team, VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150, Espoo, Finland
| | - Matthias A Hediger
- Membrane Transport Discovery Lab, Department of Biomedical Research, Inselspital, University of Bern, 3010, Bern, Switzerland
| | - Christopher P Landowski
- Protein Production Team, VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150, Espoo, Finland.
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7
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Singh H, Bhat JA, Singh VP, Corpas FJ, Yadav SR. Auxin metabolic network regulates the plant response to metalloids stress. JOURNAL OF HAZARDOUS MATERIALS 2021; 405:124250. [PMID: 33109410 DOI: 10.1016/j.jhazmat.2020.124250] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/17/2020] [Accepted: 10/08/2020] [Indexed: 05/13/2023]
Abstract
Metalloids are among the major pollutants posing a risk to the environment and global food security. Plant roots uptake these toxic metalloids from the soil along with other essential minerals. Plants respond to metalloid stress by regulating the distribution and levels of various endogenous phytohormones. Recent research showed that auxin is instrumental in mediating resilience to metalloid-induced stress in plants. Exogenous supplementation of the auxin or plant growth-promoting micro-organisms (PGPMs) alleviates metalloid uptake, localization, and accumulation in the plant tissues, thereby improving plant growth under metalloid stress. Moreover, auxin triggers various biological responses such as the production of enzymatic and non-enzymatic antioxidants to combat nitro-oxidative stress induced by the metalloids. However, an in-depth understanding of the auxin stimulated molecular and physiological responses to the metalloid toxicity needs to be investigated in future studies. The current review attempts to provide an update on the recent advances and the current state-of-the-art associated with auxin and metalloid interaction, which could be used as a start point to develop biotechnological tools and create an eco-friendly environment.
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Affiliation(s)
- Harshita Singh
- Department of Biotechnology, Indian Institute of Technology, Roorkee 247667, Uttarakhand, India
| | - Javaid Akhter Bhat
- National Center for Soybean Improvement, Key L aboratory of Biology and Genetics and Breeding for Soybean, Ministry of Agriculture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Vijay Pratap Singh
- Plant Physiology Laboratory, Department of Botany, C.M.P. Degree College, University of Allahabad, Prayagraj 211002, India
| | - Francisco J Corpas
- Department of Biochemistry, Cell and Molecular Biology, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), C/Profesor Albareda, 1, 18008 Granada, Spain
| | - Shri Ram Yadav
- Department of Biotechnology, Indian Institute of Technology, Roorkee 247667, Uttarakhand, India.
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8
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Oka M, Kamada M, Inoue R, Miyamoto K, Uheda E, Yamazaki C, Shimazu T, Sano H, Kasahara H, Suzuki T, Higashibata A, Ueda J. Altered localisation of ZmPIN1a proteins in plasma membranes responsible for enhanced-polar auxin transport in etiolated maize seedlings under microgravity conditions in space. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 47:1062-1072. [PMID: 32635987 DOI: 10.1071/fp20133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 05/31/2020] [Indexed: 06/11/2023]
Abstract
In the International Space Station experiment 'Auxin Transport', polar auxin transport (PAT) in shoots of etiolated maize (Zea mays L. cv. Golden Cross Bantam) grown under microgravity in space was substantially enhanced compared with those grown on Earth. To clarify the mechanism, the effects of microgravity on expression of ZmPIN1a encoding essential auxin efflux carrier and cellular localisation of its products were investigated. The amounts of ZmPIN1a mRNA in the coleoptiles and the mesocotyls in space-grown seedlings were almost the same as those in 1 g-grown seedlings, but its products were not. Immunohistochemical analysis with anti-ZmPIN1a antibody revealed a majority of ZmPIN1a localised in the basal side of plasma membranes of endodermal cells in the coleoptiles and the mesocotyls, and in the basal and lateral sides of plasma membranes in coleoptile parenchymatous cells, in which it directed towards the radial direction, but not towards the vascular bundle direction. Microgravity dramatically altered ZmPIN1a localisation in plasma membranes in coleoptile parenchymatous cells, shifting mainly towards the vascular bundle direction. These results suggest that mechanism of microgravity-enhanced PAT in maize shoots is more likely to be due to the enhanced ZmPIN1a accumulation and the altered ZmPIN1a localisation in parenchymatous cells of the coleoptiles.
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Affiliation(s)
- Mariko Oka
- Faculty of Agriculture, Tottori University, 4-101 Koyamacho-minami, Tottori 680-8553, Japan; and Corresponding authors. ;
| | - Motoshi Kamada
- Future Development Division, Advanced Engineering Services Co., Ltd, 1-6-1 Takezono, Tsukuba, Ibaraki 305-0032, Japan
| | - Riko Inoue
- Faculty of Agriculture, Tottori University, 4-101 Koyamacho-minami, Tottori 680-8553, Japan
| | - Kensuke Miyamoto
- Faculty of Liberal Arts and Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Eiji Uheda
- Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Chiaki Yamazaki
- JEM Mission Operations and Integration Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
| | - Toru Shimazu
- Technology and Research Promotion Department, Japan Space Forum, Shin-Otemachi Bldg., 2-2-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Hiromi Sano
- Utilization Engineering Department, Japan Manned Space Systems Corporation, Space Station Test Building, Tsukuba Space Center, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
| | - Haruo Kasahara
- Kibo Utilization Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
| | - Tomomi Suzuki
- Kibo Utilization Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
| | - Akira Higashibata
- Kibo Utilization Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
| | - Junichi Ueda
- Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan; and Corresponding authors. ;
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9
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Wang Y, Liu W, Wang H, Du Q, Fu Z, Li WX, Tang J. ZmEHD1 Is Required for Kernel Development and Vegetative Growth through Regulating Auxin Homeostasis. PLANT PHYSIOLOGY 2020; 182:1467-1480. [PMID: 31857426 PMCID: PMC7054883 DOI: 10.1104/pp.19.01336] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/08/2019] [Indexed: 05/18/2023]
Abstract
The roles of C-terminal Eps15 homology domain (EHD) proteins in clathrin-mediated endocytosis in plants are poorly understood. Here, we isolated a maize (Zea mays) mutant, designated ehd1, which showed defects in kernel development and vegetative growth. Positional cloning and transgenic analysis revealed that ehd1 encodes an EHD protein. Internalization of the endocytic tracer FM4-64 was substantially reduced in the ehd1 mutant and ZmEHD1 knockout mutants. We further demonstrated that ZmEHD1 and the ZmAP2 σ subunit physically interact at the plasma membrane. Auxin distribution and ZmPIN1a-YFP localization were altered in the ehd1 mutant. Kernel indole-3-acetic acid levels were substantially lower in the ehd1 mutant than in wild-type maize. Exogenous application of 1-naphthaleneacetic acid, but not GA3 or 2-naphthaleneacetic acid, rescued the seed germination and seedling emergency phenotypic defects of ehd1 mutants. Taken together, these results indicate that ZmEHD1 regulates auxin homeostasis by mediating clathrin-mediated endocytosis through its interaction with the ZmAP2 σ subunit, which is crucial for kernel development and vegetative growth of maize.
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Affiliation(s)
- Yafei Wang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, 450002 Zhengzhou, China
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China
| | - Wenwen Liu
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China
| | - Hongqiu Wang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, 450002 Zhengzhou, China
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China
| | - Qingguo Du
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China
| | - Zhiyuan Fu
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, 450002 Zhengzhou, China
| | - Wen-Xue Li
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China
| | - Jihua Tang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, 450002 Zhengzhou, China
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Identification of Grafting-Responsive MicroRNAs Associated with Growth Regulation in Pecan [Carya illinoinensis (Wangenh.) K. Koch]. FORESTS 2020. [DOI: 10.3390/f11020196] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Pecan [Carya illinoinensis (Wangenh.) K. Koch] is an economically important nut tree and grafting is often used for clonal propagation of cultivars. However, there is a lack of research on the effects of rootstocks on scions, which are meaningful targets for directed breeding of pecan grafts. MicroRNAs (miRNAs) play an important role in many biological processes, but the mechanism underlying the involvement of miRNAs in grafting-conferred physiological changes is unclear. To identify the grafting-responsive miRNAs that may be involved in the regulation of growth in grafted pecan, six small RNA libraries were constructed from the phloem of two groups of grafts with significantly different growth performance on short and tall rootstocks. A total of 441 conserved miRNAs belonging to 42 miRNA families and 603 novel miRNAs were identified. Among the identified miRNAs, 24 (seven conserved and 17 novel) were significantly differentially expressed by the different grafts, implying that they might be responsive to grafting and potentially involved in the regulation of graft growth. Ninety-five target genes were predicted for the differentially expressed miRNAs; gene annotation was available for 33 of these. Analysis of their targets suggested that the miRNAs may regulate auxin transport, cell activity, and inorganic phosphate (Pi) acquisition, and thereby, mediate pecan graft growth. Use of the recently-published pecan genome enabled identification of a substantial population of miRNAs, which are now available for further research. We also identified the grafting-responsive miRNAs and their potential roles in pecan graft growth, providing a basis for research on long-distance regulation in grafted pecan.
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Li P, Ding L, Zhang L, He J, Huan Z. Weisiensin B inhibits primary and lateral root development by interfering with polar auxin transport in Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 139:738-745. [PMID: 31010613 DOI: 10.1016/j.plaphy.2019.04.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 04/12/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Weisiensin B, a new ent-kaurene diterpenoid isolated from Isodon weisiensis (C. Y. Wu) H. Hara, exhibited phytotoxic effects on root growth and lateral root development in Arabidopsis thaliana seedlings. Primary root growth and lateral root formation in A. thaliana seedlings were significantly inhibited by 10-20 μM weisiensin B. Additionally, the role of weisiensin B in response to polar auxin transport in A. thaliana roots was investigated using a PIN promoter (PIN::GUS), a green fluorescent protein (GFP) fusion protein reporter (PINs::PINs:GFP), and DR5::GUS and DR5::GFP reporter genes. The results indicated that weisiensin B reduced the expression of PIN2, PIN3, PIN4, PIN7, and AUX1 genes and significantly decreased the abundance of PIN2-GFP, PIN3-GFP, PIN4-GFP, PIN7-GFP, and AUX1-GFP fusion proteins at their respective cellular locations, simultaneously causing auxin accumulation in the root apex. These results suggest that weisiensin B interferes with polar auxin transport in A. thaliana roots, resulting in auxin accumulation in the root meristematic cells and the inhibition of root growth and lateral root development.
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Affiliation(s)
- Peng Li
- College of Life Science, Northwest Normal University, China
| | - Lan Ding
- College of Life Science, Northwest Normal University, China.
| | - Li Zhang
- College of Life Science, Northwest Normal University, China
| | - Jing He
- College of Life Science, Northwest Normal University, China
| | - Zhaowei Huan
- College of Life Science, Northwest Normal University, China
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12
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Wang M, Qiao J, Yu C, Chen H, Sun C, Huang L, Li C, Geisler M, Qian Q, Jiang DA, Qi Y. The auxin influx carrier, OsAUX3, regulates rice root development and responses to aluminium stress. PLANT, CELL & ENVIRONMENT 2019; 42:1125-1138. [PMID: 30399648 DOI: 10.1111/pce.13478] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 10/25/2018] [Indexed: 05/06/2023]
Abstract
In rice, there are five members of the auxin carrier AUXIN1/LIKE AUX1 family; however, the biological functions of the other four members besides OsAUX1 remain unknown. Here, by using CRISPR/Cas9, we constructed two independent OsAUX3 knock-down lines, osaux3-1 and osaux3-2, in wild-type rice, Hwayoung (WT/HY) and Dongjin (WT/DJ). osaux3-1 and osaux3-2 have shorter primary roots (PRs), decreased lateral root (LR) density, and longer root hairs (RHs) compared with their WT. OsAUX3 expression in PRs, LRs, and RHs further supports that OsAUX3 plays a critical role in the regulation of root development. OsAUX3 locates at the plasma membrane and functions as an auxin influx carrier affecting acropetal auxin transport. OsAUX3 is up-regulated in the root apex under aluminium (Al) stress, and osaux3-2 is insensitive to Al treatments. Furthermore, 1-naphthylacetic acid accented the sensitivity of WT/DJ and osaux3-2 to respond to Al stress. Auxin concentrations, Al contents, and Al-induced reactive oxygen species-mediated damage in osaux3-2 under Al stress are lower than in WT, indicating that OsAUX3 is involved in Al-induced inhibition of root growth. This study uncovers a novel pathway alleviating Al-induced oxidative damage by inhibition of acropetal auxin transport and provides a new option for engineering Al-tolerant rice species.
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Affiliation(s)
- Mei Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - JiYue Qiao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - ChenLiang Yu
- Vegetable Research Institute, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Hao Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - ChenDong Sun
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - LinZhou Huang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - ChuanYou Li
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Markus Geisler
- Department of Biology, University of Fribourg, Fribourg, CH-1700, Switzerland
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006, China
| | - De An Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - YanHua Qi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
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Zwiewka M, Bilanovičová V, Seifu YW, Nodzyński T. The Nuts and Bolts of PIN Auxin Efflux Carriers. FRONTIERS IN PLANT SCIENCE 2019; 10:985. [PMID: 31417597 PMCID: PMC6685051 DOI: 10.3389/fpls.2019.00985] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/12/2019] [Indexed: 05/20/2023]
Abstract
The plant-specific proteins named PIN-FORMED (PIN) efflux carriers facilitate the direction of auxin flow and thus play a vital role in the establishment of local auxin maxima within plant tissues that subsequently guide plant ontogenesis. They are membrane integral proteins with two hydrophobic regions consisting of alpha-helices linked with a hydrophilic loop, which is usually longer for the plasma membrane-localized PINs. The hydrophilic loop harbors molecular cues important for the subcellular localization and thus auxin efflux function of those transporters. The three-dimensional structure of PIN has not been solved yet. However, there are scattered but substantial data concerning the functional characterization of amino acid strings that constitute these carriers. These sequences include motifs vital for vesicular trafficking, residues regulating membrane diffusion, cellular polar localization, and activity of PINs. Here, we summarize those bits of information striving to provide a reference to structural motifs that have been investigated experimentally hoping to stimulate the efforts toward unraveling of PIN structure-function connections.
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14
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Biedroń M, Banasiak A. Auxin-mediated regulation of vascular patterning in Arabidopsis thaliana leaves. PLANT CELL REPORTS 2018; 37:1215-1229. [PMID: 29992374 PMCID: PMC6096608 DOI: 10.1007/s00299-018-2319-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 07/04/2018] [Indexed: 05/02/2023]
Abstract
The vascular system develops in response to auxin flow as continuous strands of conducting tissues arranged in regular spatial patterns. However, a mechanism governing their regular and repetitive formation remains to be fully elucidated. A model system for studying the vascular pattern formation is the process of leaf vascularization in Arabidopsis. In this paper, we present current knowledge of important factors and their interactions in this process. Additionally, we propose the sequence of events leading to the emergence of continuous vascular strands and point to significant problems that need to be resolved in the future to gain a better understanding of the regulation of the vascular pattern development.
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Affiliation(s)
- Magdalena Biedroń
- Department of Plant Developmental Biology, Institute of Experimental Biology, University of Wrocław, ul. Kanonia 6/8, 50-328, Wrocław, Poland
| | - Alicja Banasiak
- Department of Plant Developmental Biology, Institute of Experimental Biology, University of Wrocław, ul. Kanonia 6/8, 50-328, Wrocław, Poland.
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15
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Park J, Lee Y, Martinoia E, Geisler M. Plant hormone transporters: what we know and what we would like to know. BMC Biol 2017; 15:93. [PMID: 29070024 PMCID: PMC5655956 DOI: 10.1186/s12915-017-0443-x] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Hormone transporters are crucial for plant hormone action, which is underlined by severe developmental and physiological impacts caused by their loss-of-function mutations. Here, we summarize recent knowledge on the individual roles of plant hormone transporters in local and long-distance transport. Our inventory reveals that many hormones are transported by members of distinct transporter classes, with an apparent dominance of the ATP-binding cassette (ABC) family and of the Nitrate transport1/Peptide transporter family (NPF). The current need to explore further hormone transporter regulation, their functional interaction, transport directionalities, and substrate specificities is briefly reviewed.
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Affiliation(s)
- Jiyoung Park
- Division of Biological Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0116, USA.
| | - Youngsook Lee
- Division of Integrative Bioscience and Biotechnology, POSTECH, Pohang, 37673, South Korea
| | - Enrico Martinoia
- Institute for Plant Biology, University of Zurich, Zollikerstrasse 107, 8008, Zurich, Switzerland
| | - Markus Geisler
- Department of Biology, University of Fribourg, 1700, Fribourg, Switzerland.
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16
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Geisler M, Aryal B, di Donato M, Hao P. A Critical View on ABC Transporters and Their Interacting Partners in Auxin Transport. PLANT & CELL PHYSIOLOGY 2017; 58:1601-1614. [PMID: 29016918 DOI: 10.1093/pcp/pcx104] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 07/18/2017] [Indexed: 05/24/2023]
Abstract
Different subclasses of ATP-binding cassette (ABC) transporters have been implicated in the transport of native variants of the phytohormone auxin. Here, the putative, individual roles of key members belonging to the ABCB, ABCD and ABCG families, respectively, are highlighted and the knowledge of their assumed expression and transport routes is reviewed and compared with their mutant phenotypes. Protein-protein interactions between ABC transporters and regulatory components during auxin transport are summarized and their importance is critically discussed. There is a focus on the functional interaction between members of the ABCB family and the FKBP42, TWISTED DWARF1, acting as a chaperone during plasma membrane trafficking of ABCBs. Further, the mode and relevance of functional ABCB-PIN interactions is diagnostically re-evaluated. A new nomenclature describing precisely the most likely ABCB-PIN interaction scenarios is suggested. Finally, available tools for the detection and prediction of ABC transporter interactomes are summarized and the potential of future ABC transporter interactome maps is highlighted.
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Affiliation(s)
- Markus Geisler
- University of Fribourg, Department of Biology, CH-1700 Fribourg, Switzerland
| | - Bibek Aryal
- University of Fribourg, Department of Biology, CH-1700 Fribourg, Switzerland
| | - Martin di Donato
- University of Fribourg, Department of Biology, CH-1700 Fribourg, Switzerland
| | - Pengchao Hao
- University of Fribourg, Department of Biology, CH-1700 Fribourg, Switzerland
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17
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Wang T, Li C, Wu Z, Jia Y, Wang H, Sun S, Mao C, Wang X. Abscisic Acid Regulates Auxin Homeostasis in Rice Root Tips to Promote Root Hair Elongation. FRONTIERS IN PLANT SCIENCE 2017; 8:1121. [PMID: 28702040 PMCID: PMC5487450 DOI: 10.3389/fpls.2017.01121] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 06/12/2017] [Indexed: 05/18/2023]
Abstract
Abscisic acid (ABA) plays an essential role in root hair elongation in plants, but the regulatory mechanism remains to be elucidated. In this study, we found that exogenous ABA can promote rice root hair elongation. Transgenic rice overexpressing SAPK10 (Stress/ABA-activated protein kinase 10) had longer root hairs; rice plants overexpressing OsABIL2 (OsABI-Like 2) had attenuated ABA signaling and shorter root hairs, suggesting that the effect of ABA on root hair elongation depends on the conserved PYR/PP2C/SnRK2 ABA signaling module. Treatment of the DR5-GUS and OsPIN-GUS lines with ABA and an auxin efflux inhibitor showed that ABA-induced root hair elongation depends on polar auxin transport. To examine the transcriptional response to ABA, we divided rice root tips into three regions: short root hair, long root hair and root tip zones; and conducted RNA-seq analysis with or without ABA treatment. Examination of genes involved in auxin transport, biosynthesis and metabolism indicated that ABA promotes auxin biosynthesis and polar auxin transport in the root tip, which may lead to auxin accumulation in the long root hair zone. Our findings shed light on how ABA regulates root hair elongation through crosstalk with auxin biosynthesis and transport to orchestrate plant development.
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Affiliation(s)
- Tao Wang
- National Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan UniversityShanghai, China
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Chengxiang Li
- National Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan UniversityShanghai, China
| | - Zhihua Wu
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Yancui Jia
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Hong Wang
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Shiyong Sun
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Chuanzao Mao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang UniversityHangzhou, China
| | - Xuelu Wang
- National Key Laboratory of Crop Genetic Improvement, Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
- *Correspondence: Xuelu Wang,
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18
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Geisler M, Bailly A, Ivanchenko M. Master and servant: Regulation of auxin transporters by FKBPs and cyclophilins. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 245:1-10. [PMID: 26940487 DOI: 10.1016/j.plantsci.2015.12.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/14/2015] [Accepted: 12/17/2015] [Indexed: 05/27/2023]
Abstract
Plant development and architecture are greatly influenced by the polar distribution of the essential hormone auxin. The directional influx and efflux of auxin from plant cells depends primarily on AUX1/LAX, PIN, and ABCB/PGP/MDR families of auxin transport proteins. The functional analysis of these proteins has progressed rapidly within the last decade thanks to the establishment of heterologous auxin transport systems. Heterologous co-expression allowed also for the testing of protein-protein interactions involved in the regulation of transporters and identified relationships with members of the FK506-Binding Protein (FKBP) and cyclophilin protein families, which are best known in non-plant systems as cellular receptors for the immunosuppressant drugs, FK506 and cyclosporin A, respectively. Current evidence that such interactions affect membrane trafficking, and potentially the activity of auxin transporters is reviewed. We also propose that FKBPs andcyclophilins might integrate the action of auxin transport inhibitors, such as NPA, on members of the ABCB and PIN family, respectively. Finally, we outline open questions that might be useful for further elucidation of the role of immunophilins as regulators (servants) of auxin transporters (masters).
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Affiliation(s)
- Markus Geisler
- University of Fribourg, Department of Biology-Plant Biology, CH-1700 Fribourg, Switzerland.
| | - Aurélien Bailly
- University of Zurich, Institute of Plant Biology, CH-8008 Zurich, Switzerland
| | - Maria Ivanchenko
- Oregon State University, Department of Botany and Plant Pathology, 2082 Cordley Hall, Corvallis, OR 97331, USA.
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19
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Druege U, Franken P, Hajirezaei MR. Plant Hormone Homeostasis, Signaling, and Function during Adventitious Root Formation in Cuttings. FRONTIERS IN PLANT SCIENCE 2016; 7:381. [PMID: 27064322 PMCID: PMC4814496 DOI: 10.3389/fpls.2016.00381] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 03/13/2016] [Indexed: 04/14/2023]
Abstract
Adventitious root (AR) formation in cuttings is a multiphase developmental process, resulting from wounding at the cutting site and isolation from the resource and signal network of the whole plant. Though, promotive effects of auxins are widely used for clonal plant propagation, the regulation and function of plant hormones and their intricate signaling networks during AR formation in cuttings are poorly understood. In this focused review, we discuss our recent publications on the involvement of polar auxin transport (PAT) and transcriptional regulation of auxin and ethylene action during AR formation in petunia cuttings in a broad context. Integrating new findings on cuttings of other plant species and general models on plant hormone networks, a model on the regulation and function of auxin, ethylene, and jasmonate in AR formation of cuttings is presented. PAT and cutting off from the basipetal auxin drain are considered as initial principles generating early accumulation of IAA in the rooting zone. This is expected to trigger a self-regulatory process of auxin canalization and maximization to responding target cells, there inducing the program of AR formation. Regulation of auxin homeostasis via auxin influx and efflux carriers, GH3 proteins and peroxidases, of flavonoid metabolism, and of auxin signaling via AUX/IAA proteins, TOPLESS, ARFs, and SAUR-like proteins are postulated as key processes determining the different phases of AR formation. NO and H2O2 mediate auxin signaling via the cGMP and MAPK cascades. Transcription factors of the GRAS-, AP2/ERF-, and WOX-families link auxin signaling to cell fate specification. Cyclin-mediated governing of the cell cycle, modifications of sugar metabolism and microtubule and cell wall remodeling are considered as important implementation processes of auxin function. Induced by the initial wounding and other abiotic stress factors, up-regulation of ethylene biosynthesis, and signaling via ERFs and early accumulation of jasmonic acid stimulate AR formation, while both pathways are linked to auxin. Future research on the function of candidate genes should consider their tissue-specific role and regulation by environmental factors. Furthermore, the whole cutting should be regarded as a system of physiological units with diverse functions specifically responding to the environment and determining the rooting response.
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Affiliation(s)
- Uwe Druege
- Department Plant Propagation, Leibniz Institute of Vegetable and Ornamental CropsErfurt, Germany
- *Correspondence:
| | - Philipp Franken
- Department Plant Propagation, Leibniz Institute of Vegetable and Ornamental CropsErfurt, Germany
| | - Mohammad R. Hajirezaei
- Department of Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant ResearchGatersleben, Germany
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20
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Zhao H, Ma T, Wang X, Deng Y, Ma H, Zhang R, Zhao J. OsAUX1 controls lateral root initiation in rice (Oryza sativa L.). PLANT, CELL & ENVIRONMENT 2015; 38:2208-22. [PMID: 25311360 DOI: 10.1111/pce.12467] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 10/01/2014] [Indexed: 05/06/2023]
Abstract
Polar auxin transport, mediated by influx and efflux transporters, controls many aspects of plant growth and development. The auxin influx carriers in Arabidopsis have been shown to control lateral root development and gravitropism, but little is known about these proteins in rice. This paper reports on the functional characterization of OsAUX1. Three OsAUX1 T-DNA insertion mutants and RNAi knockdown transgenic plants reduced lateral root initiation compared with wild-type (WT) plants. OsAUX1 overexpression plants exhibited increased lateral root initiation and OsAUX1 was highly expressed in lateral roots and lateral root primordia. Similarly, the auxin reporter, DR5-GUS, was expressed at lower levels in osaux1 than in the WT plants, which indicated that the auxin levels in the mutant roots had decreased. Exogenous 1-naphthylacetic acid (NAA) treatment rescued the defective phenotype in osaux1-1 plants, whereas indole-3-acetic acid (IAA) and 2,4-D could not, which suggested that OsAUX1 was a putative auxin influx carrier. The transcript levels of several auxin signalling genes and cell cycle genes significantly declined in osaux1, hinting that the regulatory role of OsAUX1 may be mediated by auxin signalling and cell cycle genes. Overall, our results indicated that OsAUX1 was involved in polar auxin transport and functioned to control auxin-mediated lateral root initiation in rice.
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Affiliation(s)
- Heming Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Tengfei Ma
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xin Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yingtian Deng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Haoli Ma
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Rongsheng Zhang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jie Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
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21
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Yu C, Sun C, Shen C, Wang S, Liu F, Liu Y, Chen Y, Li C, Qian Q, Aryal B, Geisler M, Jiang DA, Qi Y. The auxin transporter, OsAUX1, is involved in primary root and root hair elongation and in Cd stress responses in rice (Oryza sativa L.). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 83:818-30. [PMID: 26140668 DOI: 10.1111/tpj.12929] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 06/17/2015] [Accepted: 06/26/2015] [Indexed: 05/22/2023]
Abstract
Auxin and cadmium (Cd) stress play critical roles during root development. There are only a few reports on the mechanisms by which Cd stress influences auxin homeostasis and affects primary root (PR) and lateral root (LR) development, and almost nothing is known about how auxin and Cd interfere with root hair (RH) development. Here, we characterize rice osaux1 mutants that have a longer PR and shorter RHs in hydroponic culture, and that are more sensitive to Cd stress compared to wild-type (Dongjin). OsAUX1 expression in root hair cells is different from that of its paralogous gene, AtAUX1, which is expressed in non-hair cells. However, OsAUX1, like AtAUX1, localizes at the plasma membrane and appears to function as an auxin tranporter. Decreased auxin distribution and contents in the osaux1 mutant result in reduction of OsCyCB1;1 expression and shortened PRs, LRs and RHs under Cd stress, but may be rescued by treatment with the membrane-permeable auxin 1-naphthalene acetic acid. Treatment with the auxin transport inhibitors 1-naphthoxyacetic acid and N-1-naphthylphthalamic acid increased the Cd sensitivity of WT rice. Cd contents in the osaux1 mutant were not altered, but reactive oxygen species-mediated damage was enhanced, further increasing the sensitivity of the osaux1 mutant to Cd stress. Taken together, our results indicate that OsAUX1 plays an important role in root development and in responses to Cd stress.
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Affiliation(s)
- ChenLiang Yu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - ChenDong Sun
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Chenjia Shen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China
| | - Suikang Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Fang Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yan Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - YunLong Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Chuanyou Li
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Bibek Aryal
- Department of Biology - Plant Biology, University of Fribourg, Rue Albert Gockel 3, CH-1700, Fribourg, Switzerland
| | - Markus Geisler
- Department of Biology - Plant Biology, University of Fribourg, Rue Albert Gockel 3, CH-1700, Fribourg, Switzerland
| | - De An Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - YanHua Qi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
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Ng JLP, Perrine-Walker F, Wasson AP, Mathesius U. The Control of Auxin Transport in Parasitic and Symbiotic Root-Microbe Interactions. PLANTS (BASEL, SWITZERLAND) 2015; 4:606-43. [PMID: 27135343 PMCID: PMC4844411 DOI: 10.3390/plants4030606] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 08/12/2015] [Accepted: 08/18/2015] [Indexed: 01/13/2023]
Abstract
Most field-grown plants are surrounded by microbes, especially from the soil. Some of these, including bacteria, fungi and nematodes, specifically manipulate the growth and development of their plant hosts, primarily for the formation of structures housing the microbes in roots. These developmental processes require the correct localization of the phytohormone auxin, which is involved in the control of cell division, cell enlargement, organ development and defense, and is thus a likely target for microbes that infect and invade plants. Some microbes have the ability to directly synthesize auxin. Others produce specific signals that indirectly alter the accumulation of auxin in the plant by altering auxin transport. This review highlights root-microbe interactions in which auxin transport is known to be targeted by symbionts and parasites to manipulate the development of their host root system. We include case studies for parasitic root-nematode interactions, mycorrhizal symbioses as well as nitrogen fixing symbioses in actinorhizal and legume hosts. The mechanisms to achieve auxin transport control that have been studied in model organisms include the induction of plant flavonoids that indirectly alter auxin transport and the direct targeting of auxin transporters by nematode effectors. In most cases, detailed mechanisms of auxin transport control remain unknown.
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Affiliation(s)
- Jason Liang Pin Ng
- Division of Plant Science, Research School of Biology, Australian National University, Linnaeus Way, Building 134, Canberra ACT 2601, Australia.
| | | | | | - Ulrike Mathesius
- Division of Plant Science, Research School of Biology, Australian National University, Linnaeus Way, Building 134, Canberra ACT 2601, Australia.
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Lee HW, Cho C, Kim J. Lateral Organ Boundaries Domain16 and 18 Act Downstream of the AUXIN1 and LIKE-AUXIN3 Auxin Influx Carriers to Control Lateral Root Development in Arabidopsis. PLANT PHYSIOLOGY 2015; 168:1792-806. [PMID: 26059335 PMCID: PMC4528759 DOI: 10.1104/pp.15.00578] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/08/2015] [Indexed: 05/22/2023]
Abstract
Several members of the Lateral Organ Boundaries Domain (LBD)/Asymmetric Leaves2-Like (ASL) gene family have been identified to play important roles in Arabidopsis (Arabidopsis thaliana) lateral root (LR) development during auxin response, but their functional relationship with auxin transporters has not been established yet. Here, we show that the AUXIN1 (AUX1) and LIKE-AUXIN3 (LAX3) auxin influx carriers are required for auxin signaling that activates LBD16/ASL18 and LBD18/ASL20 to control LR development. The lax3 mutant phenotype was not significantly enhanced when combined with lbd16 or lbd18. However, LBD18 overexpression could rescue the defects in LR emergence in lax3 with concomitant expression of the LBD18 target genes. Genetic and gene expression analyses indicated that LBD16 and LBD18 act with AUX1 to regulate LR initiation and LR primordium development, and that AUX1 and LAX3 are needed for auxin-responsive expression of LBD16 and LBD18. LBD18:SUPERMAN REPRESSIVE DOMAIN X in the lbd18 mutant inhibited LR initiation and LR primordium development in response to a gravitropic stimulus and suppressed promoter activities of the cell cycle genes Cyclin-Dependent Kinase A1;1 and CYCLINB1;1. Taken together, these results suggest that LBD16 and LBD18 are important regulators of LR initiation and development downstream of AUX1 and LAX3.
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Affiliation(s)
- Han Woo Lee
- Department of Bioenergy Science and Technology and Kumho Life Science Laboratory, Chonnam National University, Gwangju 500-757, Korea
| | - Chuloh Cho
- Department of Bioenergy Science and Technology and Kumho Life Science Laboratory, Chonnam National University, Gwangju 500-757, Korea
| | - Jungmook Kim
- Department of Bioenergy Science and Technology and Kumho Life Science Laboratory, Chonnam National University, Gwangju 500-757, Korea
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Krishnamurthy A, Rathinasabapathi B. Auxin and its transport play a role in plant tolerance to arsenite-induced oxidative stress in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2013; 36:1838-49. [PMID: 23489261 DOI: 10.1111/pce.12093] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 03/01/2013] [Accepted: 03/02/2013] [Indexed: 05/08/2023]
Abstract
The role of auxin in plant development is well known; however, its possible function in root response to abiotic stress is poorly understood. In this study, we demonstrate a novel role of auxin transport in plant tolerance to oxidative stress caused by arsenite. Plant response to arsenite [As(III)] was evaluated by measuring root growth and markers for stress on seedlings treated with control or As(III)-containing medium. Auxin transporter mutants aux1, pin1 and pin2 were significantly more sensitive to As(III) than the wild type (WT). Auxin transport inhibitors significantly reduced plant tolerance to As(III) in the WT, while exogenous supply of indole-3-acetic acid improved As(III) tolerance of aux1 and not that of WT. Uptake assays using H(3) -IAA showed As(III) affected auxin transport in WT roots. As(III) increased the levels of H2 O2 in WT but not in aux1, suggesting a positive role for auxin transport through AUX1 on plant tolerance to As(III) stress via reactive oxygen species (ROS)-mediated signalling. Compared to the WT, the mutant aux1 was significantly more sensitive to high-temperature stress and salinity, also suggesting auxin transport influences a common element shared by plant tolerance to arsenite, salinity and high-temperature stress.
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Affiliation(s)
- Aparna Krishnamurthy
- Horticultural Sciences Department, University of Florida, Gainesville, FL 32611-0690, USA
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Ahkami AH, Melzer M, Ghaffari MR, Pollmann S, Ghorbani Javid M, Shahinnia F, Hajirezaei MR, Druege U. Distribution of indole-3-acetic acid in Petunia hybrida shoot tip cuttings and relationship between auxin transport, carbohydrate metabolism and adventitious root formation. PLANTA 2013; 238:499-517. [PMID: 23765266 PMCID: PMC3751230 DOI: 10.1007/s00425-013-1907-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 05/28/2013] [Indexed: 05/21/2023]
Abstract
To determine the contribution of polar auxin transport (PAT) to auxin accumulation and to adventitious root (AR) formation in the stem base of Petunia hybrida shoot tip cuttings, the level of indole-3-acetic acid (IAA) was monitored in non-treated cuttings and cuttings treated with the auxin transport blocker naphthylphthalamic acid (NPA) and was complemented with precise anatomical studies. The temporal course of carbohydrates, amino acids and activities of controlling enzymes was also investigated. Analysis of initial spatial IAA distribution in the cuttings revealed that approximately 40 and 10 % of the total IAA pool was present in the leaves and the stem base as rooting zone, respectively. A negative correlation existed between leaf size and IAA concentration. After excision of cuttings, IAA showed an early increase in the stem base with two peaks at 2 and 24 h post excision and, thereafter, a decline to low levels. This was mirrored by the expression pattern of the auxin-responsive GH3 gene. NPA treatment completely suppressed the 24-h peak of IAA and severely inhibited root formation. It also reduced activities of cell wall and vacuolar invertases in the early phase of AR formation and inhibited the rise of activities of glucose-6-phosphate dehydrogenase and phosphofructokinase during later stages. We propose a model in which spontaneous AR formation in Petunia cuttings is dependent on PAT and on the resulting 24-h peak of IAA in the rooting zone, where it induces early cellular events and also stimulates sink establishment. Subsequent root development stimulates glycolysis and the pentose phosphate pathway.
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Affiliation(s)
- Amir H. Ahkami
- Institute of Biological Chemistry (IBC), Washington State University, Pullman, WA 99164-6340 USA
| | - Michael Melzer
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, Gatersleben, 06466 Seeland, Germany
| | - Mohammad R. Ghaffari
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, Gatersleben, 06466 Seeland, Germany
| | - Stephan Pollmann
- Parque Científico y Tecnológico de la U.P.M, Centro de Biotecnología y Genómica de Plantas U.P.M.-I.N.I.A, Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Majid Ghorbani Javid
- Department of Agronomy and Plant Breeding Sciences, College of Abureihan, University of Tehran, Tehran, Iran
| | - Fahimeh Shahinnia
- Australian Centre for Plant Functional Genomics, University of Adelaide, Waite Campus, Hartley Grove Urrbrae, Adelaide, 5064 Australia
| | - Mohammad R. Hajirezaei
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, Gatersleben, 06466 Seeland, Germany
| | - Uwe Druege
- Leibniz Institute of Vegetable and Ornamental Crops Großbeeren/Erfurt e.V. (IGZ), Kuehnhaeuser Str. 101, 99090 Erfurt, Germany
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Cell polarity and patterning by PIN trafficking through early endosomal compartments in Arabidopsis thaliana. PLoS Genet 2013; 9:e1003540. [PMID: 23737757 PMCID: PMC3667747 DOI: 10.1371/journal.pgen.1003540] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 04/16/2013] [Indexed: 01/15/2023] Open
Abstract
PIN-FORMED (PIN) proteins localize asymmetrically at the plasma membrane and mediate intercellular polar transport of the plant hormone auxin that is crucial for a multitude of developmental processes in plants. PIN localization is under extensive control by environmental or developmental cues, but mechanisms regulating PIN localization are not fully understood. Here we show that early endosomal components ARF GEF BEN1 and newly identified Sec1/Munc18 family protein BEN2 are involved in distinct steps of early endosomal trafficking. BEN1 and BEN2 are collectively required for polar PIN localization, for their dynamic repolarization, and consequently for auxin activity gradient formation and auxin-related developmental processes including embryonic patterning, organogenesis, and vasculature venation patterning. These results show that early endosomal trafficking is crucial for cell polarity and auxin-dependent regulation of plant architecture. Auxin is a unique plant hormone, which is actively and directionally transported in plant tissues. Transported auxin locally accumulates in the plant body and triggers a multitude of responses, including organ formation and patterning. Therefore, regulation of the directional auxin transport is very important in multiple aspects of plant development. The PIN-FORMED (PIN) family of auxin transporters is known to localize at specific sides of cells and export auxin from the cells, enabling the directional transport of auxin in the tissues. PIN proteins are rapidly shuttling between the plasma membrane and intracellular compartments, potentially allowing dynamic changes of the asymmetric localization according to developmental and environmental cues. Here, we discovered that a mutation in the Sec1/Munc18 family protein VPS45 abolishes its own early endosomal localization and compromises intracellular trafficking of PIN proteins. By genetic and pharmacological inhibition of early endosomal trafficking, we also revealed that another early endosomal protein, ARF GEF BEN1, is involved in early endosomal trafficking at a distinct step. Furthermore, we showed that these components play crucial roles in polar localization and dynamic repolarization of PIN proteins, which underpin various developmental processes. These findings highlight the indispensable roles of early endosomal components in regulating PIN polarity and plant architecture.
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Li J, Jia H. cGMP modulates Arabidopsis lateral root formation through regulation of polar auxin transport. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 66:105-17. [PMID: 23500713 DOI: 10.1016/j.plaphy.2013.02.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 02/15/2013] [Indexed: 05/02/2023]
Abstract
The phytohormone auxin participates in lateral root formation and primary root growth in plants. The auxin gradient formation is mainly regulated by the direction of polar auxin transport (PAT). PAT requires PIN family proteins, which are auxin transport facilitators and contribute to the establishment and maintenance of auxin gradients and mediate multiple developmental processes. Here, we report the effect of the 3', 5'-cyclic guanosine monophosphate (cGMP), an important second messenger, on postembryonic developmental of Arabidopsis lateral root. We find that enhanced cGMP level through the application of the membrane permeable cGMP analog 8-Br-cGMP, promotes the initiation of lateral root primordia and formation of lateral root. 6-Anilino-5,8-quinolinedione (Ly83583, the guanylate cyclase inhibitor) negatively regulates the process. cGMP also mediates acropetal auxin transport and basipetal auxin transport in the root. We further find that 8-Br-cGMP and Ly83583 change the expression of auxin transport genes and alter the polar localization and expression of PIN1 and PIN2 proteins. Moreover, Ly83583 affects actin organization and localization. Taken together, we propose that cGMP affects auxin transport and auxin gradient through modulation PINs proteins localization and expression. cGMP regulates postembryonic formation of Arabidopsis lateral root through the crosstalk with PAT.
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Affiliation(s)
- Jisheng Li
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China.
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Yu J, Wen CK. Arabidopsis aux1rcr1 mutation alters AUXIN RESISTANT1 targeting and prevents expression of the auxin reporter DR5:GUS in the root apex. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:921-33. [PMID: 23293348 PMCID: PMC3580809 DOI: 10.1093/jxb/ers371] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Multilevel interactions of the plant hormones ethylene and auxin coordinately and synergistically regulate many aspects of plant growth and development. This study isolated the AUXIN RESISTANT1 (AUX1) allele aux1(rcr1) (RCR1 for REVERSING CTR1-10 ROOT1) that suppressed the root growth inhibition conferred by the constitutive ethylene-response constitutive triple response1-10 (ctr1-10) allele. The aux1(rcr1) mutation resulted from an L126F substitution at loop 2 of the plasma membrane-associated auxin influx carrier protein AUX1. aux1(rcr1) and the T-DNA insertion mutant aux1-T were both defective in auxin transport and many aspects of the auxin response. Unexpectedly, expression of the auxin-response reporter DR5:GUS in the root apex was substantially prevented by the aux1(rcr1) but not the aux1-T mutation, even in the presence of the wild-type AUX1 allele. Following treatment with the synthetic auxin 1-naphthaleneacetic acid (NAA), DR5:GUS expression in aux1(rcr1) and aux1-T occurred mainly in the root apex and mature zone. NAA-induced DR5:GUS expression in the root apex was markedly prevented by ethylene in genotypes with aux1(rcr1) but not in aux1-T genotypes and the wild type. The effect of aux1(rcr1) on DR5:GUS expression seemed to be associated with AUX1-expressing domains. Green fluorescence protein-fused aux1(rcr1) was localized in the cytoplasm and probably not to the plasma membrane, indicating important roles of the Lys(126) residue at loop 2 in AUX1 targeting. The possible effects of aux1(rcr1) on DR5:GUS expression are discussed.
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Affiliation(s)
- Jing Yu
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
| | - Chi-Kuang Wen
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
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da Costa CT, de Almeida MR, Ruedell CM, Schwambach J, Maraschin FS, Fett-Neto AG. When stress and development go hand in hand: main hormonal controls of adventitious rooting in cuttings. FRONTIERS IN PLANT SCIENCE 2013; 4:133. [PMID: 23717317 PMCID: PMC3653114 DOI: 10.3389/fpls.2013.00133] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 04/21/2013] [Indexed: 05/18/2023]
Abstract
Adventitious rooting (AR) is a multifactorial response leading to new roots at the base of stem cuttings, and the establishment of a complete and autonomous plant. AR has two main phases: (a) induction, with a requirement for higher auxin concentration; (b) formation, inhibited by high auxin and in which anatomical changes take place. The first stages of this process in severed organs necessarily include wounding and water stress responses which may trigger hormonal changes that contribute to reprogram target cells that are competent to respond to rooting stimuli. At severance, the roles of jasmonate and abscisic acid are critical for wound response and perhaps sink strength establishment, although their negative roles on the cell cycle may inhibit root induction. Strigolactones may also inhibit AR. A reduced concentration of cytokinins in cuttings results from the separation of the root system, whose tips are a relevant source of these root induction inhibitors. The combined increased accumulation of basipetally transported auxins from the shoot apex at the cutting base is often sufficient for AR in easy-to-root species. The role of peroxidases and phenolic compounds in auxin catabolism may be critical at these early stages right after wounding. The events leading to AR strongly depend on mother plant nutritional status, both in terms of minerals and carbohydrates, as well as on sink establishment at cutting bases. Auxins play a central role in AR. Auxin transporters control auxin canalization to target cells. There, auxins act primarily through selective proteolysis and cell wall loosening, via their receptor proteins TIR1 (transport inhibitor response 1) and ABP1 (Auxin-Binding Protein 1). A complex microRNA circuitry is involved in the control of auxin response factors essential for gene expression in AR. After root establishment, new hormonal controls take place, with auxins being required at lower concentrations for root meristem maintenance and cytokinins needed for root tissue differentiation.
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Affiliation(s)
- Cibele T. da Costa
- Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
- Cibele T. da Costa and Márcia R. de Almeida have contributed equally to this work
| | - Márcia R. de Almeida
- Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
- Cibele T. da Costa and Márcia R. de Almeida have contributed equally to this work
| | - Carolina M. Ruedell
- Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Joseli Schwambach
- Institute of Biotechnology, University of Caxias do Sul, Caxias do Sul, Rio Grande do Sul, Brazil
| | - Felipe S. Maraschin
- Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Arthur G. Fett-Neto
- Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
- *Correspondence: Arthur G. Fett-Neto, Plant Physiology Laboratory, Center for Biotechnology and Department of Botany, Federal University of Rio Grande do Sul, P.O. Box 15005, Porto Alegre 91501-970, Rio Grande do Sul, Brazil. e-mail:
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Hohm T, Preuten T, Fankhauser C. Phototropism: translating light into directional growth. AMERICAN JOURNAL OF BOTANY 2013; 100:47-59. [PMID: 23152332 DOI: 10.3732/ajb.1200299] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Phototropism allows plants to align their photosynthetic tissues with incoming light. The direction of incident light is sensed by the phototropin family of blue light photoreceptors (phot1 and phot2 in Arabidopsis), which are light-activated protein kinases. The kinase activity of phototropins and phosphorylation of residues in the activation loop of their kinase domains are essential for the phototropic response. These initial steps trigger the formation of the auxin gradient across the hypocotyl that leads to asymmetric growth. The molecular events between photoreceptor activation and the growth response are only starting to be elucidated. In this review, we discuss the major steps leading from light perception to directional growth concentrating on Arabidopsis. In addition, we highlight links that connect these different steps enabling the phototropic response.
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Affiliation(s)
- Tim Hohm
- Department of Medical Genetics, Faculty of Biology and Medicine, University of Lausanne, Rue du Bugnon 27, CH-1005 Lausanne, Switzerland
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Li YH, Zou MH, Feng BH, Huang X, Zhang Z, Sun GM. Molecular cloning and characterization of the genes encoding an auxin efflux carrier and the auxin influx carriers associated with the adventitious root formation in mango (Mangifera indica L.) cotyledon segments. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2012; 55:33-42. [PMID: 22522578 DOI: 10.1016/j.plaphy.2012.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 03/13/2012] [Indexed: 05/04/2023]
Abstract
Polar auxin transport (PAT) plays an important role in the adventitious root formation of mango cotyledon segments, but the molecular mechanism remains unclear. In this study, we cloned a gene encoding an auxin efflux carrier (designated as MiPIN1), and we cloned four genes encoding auxin influx carriers (designated as MiAUX1, MiAUX2, MiAUX3 and MiAUX4). The results of a phylogenetic tree analysis indicated that MiPIN1 and the MiAUXs belong to plant PIN and AUXs/LAXs groups. Quantitative real-time PCR indicated that the expression of MiPIN1 and the MiAUXs was lowest at 0 days but sharply increased on and after day 4. During the root formation in the mango cotyledon segments, the MiPIN1 expression in the distal cut surface (DCS) was always higher than the expression in the proximal cut surface (PCS) whereas the expression of the MiAUXs in the PCS was usually higher than in the DCS. This expression pattern might be result in the PAT from the DCS to the PCS, which is essential for the adventitious root formation in the PCS. Our previous study indicated that a pre-treatment of embryos with indole-3-butyric acid (IBA) significantly promoted adventitious rooting in PCS whereas a pre-treatment with 2,3,5-triiodobenzoic acid (TIBA) completely inhibited this rooting. In this study, however, IBA and TIBA pre-treatments slightly changed the expression of MiPIN1. In contrast, while the MiAUX3 and MiAUX4 expression levels were significantly up-regulated by the IBA pre-treatment, the expression levels were down-regulated by the TIBA pre-treatment. These findings imply that MiAUX3 and MiAUX4 are more sensitive to the IBA and TIBA treatments and that they might play important roles during adventitious root formation in mango cotyledon segments.
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Affiliation(s)
- Yun-He Li
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Science, No. 1 Huxiu Road, Zhanjiang 524091, People's Republic of China.
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Pattison RJ, Catalá C. Evaluating auxin distribution in tomato (Solanum lycopersicum) through an analysis of the PIN and AUX/LAX gene families. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 70:585-98. [PMID: 22211518 DOI: 10.1111/j.1365-313x.2011.04895.x] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The temporal and spatial control of auxin distribution has a key role in the regulation of plant growth and development, and much has been learnt about the mechanisms that influence auxin pools and gradients in vegetative tissues, particularly in Arabidopsis. For example polar auxin transport, mediated by PIN and AUX/LAX proteins, is central to the control of auxin distribution. In contrast, very little information is known about the dynamics of auxin distribution and the molecular basis of its transport within and between fruit tissues, despite the fact that auxin regulates many aspects of fruit development, which include fruit formation, expansion, ripening and abscission. In addition, functional information regarding the key regulators of auxin fluxes during both vegetative and reproductive development in species other than Arabidopsis is scarce. To address these issues, we have investigated the spatiotemporal distribution of auxin during tomato (Solanum lycopersicum) fruit development and the function of the PIN and AUX/LAX gene families. Differential concentrations of auxin become apparent during early fruit growth, with auxin levels being higher in internal tissues than in the fruit pericarp and the pattern of auxin accumulation depended on polar transport. Ten tomato PIN (SlPIN1 to 10) and five AUX/LAX (SlLAX1 to 5) genes were identified and found to display heterogeneous expression patterns, with tissue and developmental-stage specificity. RNAi-mediated co-silencing of SlPIN4 and SlPIN3 did not affect fruit development, which suggested functional redundancy of PIN proteins, but did lead to a vegetative phenotype, and revealed a role for these genes in the regulation of tomato shoot architecture.
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Forestan C, Farinati S, Varotto S. The Maize PIN Gene Family of Auxin Transporters. FRONTIERS IN PLANT SCIENCE 2012; 3:16. [PMID: 22639639 PMCID: PMC3355596 DOI: 10.3389/fpls.2012.00016] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 01/17/2012] [Indexed: 05/19/2023]
Abstract
Auxin is a key regulator of plant development and its differential distribution in plant tissues, established by a polar cell to cell transport, can trigger a wide range of developmental processes. A few members of the two families of auxin efflux transport proteins, PIN-formed (PIN) and P-glycoprotein (ABCB/PGP), have so far been characterized in maize. Nine new Zea mays auxin efflux carriers PIN family members and two maize PIN-like genes have now been identified. Four members of PIN1 (named ZmPIN1a-d) cluster, one gene homologous to AtPIN2 (ZmPIN2), three orthologs of PIN5 (ZmPIN5a-c), one gene paired with AtPIN8 (ZmPIN8), and three monocot-specific PINs (ZmPIN9, ZmPIN10a, and ZmPIN10b) were cloned and the phylogenetic relationships between early-land plants, monocots, and eudicots PIN proteins investigated, including the new maize PIN proteins. Tissue-specific expression patterns of the 12 maize PIN genes, 2 PIN-like genes and ZmABCB1, an ABCB auxin efflux carrier, were analyzed together with protein localization and auxin accumulation patterns in normal conditions and in response to drug applications. ZmPIN gene transcripts have overlapping expression domains in the root apex, during male and female inflorescence differentiation and kernel development. However, some PIN family members have specific tissue localization: ZmPIN1d transcript marks the L1 layer of the shoot apical meristem and inflorescence meristem during the flowering transition and the monocot-specific ZmPIN9 is expressed in the root endodermis and pericycle. The phylogenetic and gene structure analyses together with the expression pattern of the ZmPIN gene family indicate that subfunctionalization of some maize PINs can be associated to the differentiation and development of monocot-specific organs and tissues and might have occurred after the divergence between dicots and monocots.
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Affiliation(s)
- Cristian Forestan
- Department of Agronomy, Food, Natural Resources, Animal and Environment, University of PadovaLegnaro, Italy
| | - Silvia Farinati
- Department of Agronomy, Food, Natural Resources, Animal and Environment, University of PadovaLegnaro, Italy
| | - Serena Varotto
- Department of Agronomy, Food, Natural Resources, Animal and Environment, University of PadovaLegnaro, Italy
- *Correspondence: Serena Varotto, Department of Agronomy, Food, Natural Resources, Animal and Environment DAFNAE, University of Padova, Viale dell’Università 16, 35020 Legnaro, Padova, Italy. e-mail:
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Steinacher A, Leyser O, Clayton RH. A computational model of auxin and pH dynamics in a single plant cell. J Theor Biol 2011; 296:84-94. [PMID: 22142622 DOI: 10.1016/j.jtbi.2011.11.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 11/17/2011] [Accepted: 11/18/2011] [Indexed: 01/27/2023]
Abstract
Directed cell-to-cell movement of the plant growth hormone auxin is often referred to as polar auxin transport, and has gained much interest since its discovery at the beginning of the 20th century, both by biologists and theoreticians. Computational modelling of auxin transport at tissue and whole plant scales has given valuable insights into the feedback dynamics between auxin and its transport, which often leads to cell polarisation. However, one cellular feedback mechanism that has been overlooked so far in previous models is the interplay between auxin and pH during auxin transport, even though this is well known from biology. We propose a kinetic model of such a feedback mechanism, linking knowledge about auxin-induced acidification of cell wall compartments to the chemiosmotic hypothesis of auxin transport. Our results suggest that proton fluxes may play a significant role in auxin transport. Since active auxin transport relies on the proton motive force over the cellular membrane, allocation of auxin is linked to its effects on compartmental pH. Our auxin/pH feedback model predicts enhanced accumulation of auxin in cells and increases in both auxin influx and efflux when this feedback is in effect. These results were robust in all simulations and consistent with biological evidence, thus providing a framework for generating and testing hypotheses of auxin-related polarisation events at a cellular level.
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Affiliation(s)
- Arno Steinacher
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road, Exeter EX4 4QF, UK.
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Paul AL, Manak MS, Mayfield JD, Reyes MF, Gurley WB, Ferl RJ. Parabolic flight induces changes in gene expression patterns in Arabidopsis thaliana. ASTROBIOLOGY 2011; 11:743-58. [PMID: 21970703 DOI: 10.1089/ast.2011.0659] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Our primary objective was to evaluate gene expression changes in Arabidopsis thaliana in response to parabolic flight as part of a comprehensive approach to the molecular biology of spaceflight-related adaptations. In addition, we wished to establish parabolic flight as a tractable operations platform for molecular biology studies. In a succession of experiments on NASA's KC-135 and C-9 parabolic aircraft, Arabidopsis plants were presented with replicated exposure to parabolic flight. Transcriptome profiling revealed that parabolic flight caused changes in gene expression patterns that stood the statistical tests of replication on three different flight days. The earliest response, after 20 parabolas, was characterized by a prominence of genes associated with signal transduction. After 40 parabolas, this prominence was largely replaced by genes associated with biotic and abiotic stimuli and stress. Among these responses, three metabolic processes stand out in particular: the induction of auxin metabolism and signaling, the differential expression of genes associated with calcium-mediated signaling, and the repression of genes associated with disease resistance and cell wall biochemistry. Many, but not all, of these responses are known to be involved in gravity sensing in plants. Changes in auxin-related gene expression were also recorded by reporter genes tuned to auxin signal pathways. These data demonstrate that the parabolic flight environment is appropriate for molecular biology research involving the transition to microgravity, in that with replication, proper controls, and analyses, gene expression changes can be observed in the time frames of typical parabolic flight experiments.
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Affiliation(s)
- Anna-Lisa Paul
- Horticultural Sciences and Genetics Institute, University of Florida, Gainesville, USA
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Na X, Hu Y, Yue K, Lu H, Jia P, Wang H, Wang X, Bi Y. Narciclasine modulates polar auxin transport in Arabidopsis roots. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:1149-1156. [PMID: 21511360 DOI: 10.1016/j.jplph.2011.01.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 01/24/2011] [Accepted: 01/27/2011] [Indexed: 05/26/2023]
Abstract
Plant development displays an exceptional plasticity and adaptability that involves the dynamic, asymmetric distribution of the phytohormone auxin. Polar auxin flow, which requires transport facilitators of the PIN family, largely contributes to the establishment and maintenance of auxin gradients and mediates multiple developmental processes. Here, we report the effects of narciclasine (NCS), an Amaryllidaceae alkaloid isolated from Narcissus tazetta bulbs, on postembryonic development of Arabidopsis roots. Arabidopsis seedlings grown on NCS showed defects in root gravitropism which correlates with a reduction in auxin transport in roots. Expressions of auxin transport genes were affected and the polar localization of PIN2 protein was altered under NCS treatment. Taken together, we propose that NCS modulates auxin transport gene expression and PIN2 localization, and thus affects auxin transport and auxin distribution necessary for postembryonic development of Arabidopsis roots.
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Affiliation(s)
- Xiaofan Na
- School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
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Peer WA, Blakeslee JJ, Yang H, Murphy AS. Seven things we think we know about auxin transport. MOLECULAR PLANT 2011; 4:487-504. [PMID: 21505044 DOI: 10.1093/mp/ssr034] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Polar transport of the phytohormone auxin and the establishment of localized auxin maxima regulate embryonic development, stem cell maintenance, root and shoot architecture, and tropic growth responses. The past decade has been marked by dramatic progress in efforts to elucidate the complex mechanisms by which auxin transport regulates plant growth. As the understanding of auxin transport regulation has been increasingly elaborated, it has become clear that this process is involved in almost all plant growth and environmental responses in some way. However, we still lack information about some basic aspects of this fundamental regulatory mechanism. In this review, we present what we know (or what we think we know) and what we do not know about seven auxin-regulated processes. We discuss the role of auxin transport in gravitropism in primary and lateral roots, phototropism, shoot branching, leaf expansion, and venation. We also discuss the auxin reflux/fountain model at the root tip, flavonoid modulation of auxin transport processes, and outstanding aspects of post-translational regulation of auxin transporters. This discussion is not meant to be exhaustive, but highlights areas in which generally held assumptions require more substantive validation.
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Affiliation(s)
- Wendy Ann Peer
- Department of Horticulture, 625 Agriculture Mall Drive, Purdue University, West Lafayette, IN 47907, USA.
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De Smet I, Voss U, Lau S, Wilson M, Shao N, Timme RE, Swarup R, Kerr I, Hodgman C, Bock R, Bennett M, Jürgens G, Beeckman T. Unraveling the evolution of auxin signaling. PLANT PHYSIOLOGY 2011; 155:209-21. [PMID: 21081694 PMCID: PMC3075796 DOI: 10.1104/pp.110.168161] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Auxin signaling is central to plant growth and development, yet hardly anything is known about its evolutionary origin. While the presence of key players in auxin signaling has been analyzed in various land plant species, similar analyses in the green algal lineages are lacking. Here, we survey the key players in auxin biology in the available genomes of Chlorophyta species. We found that the genetic potential for auxin biosynthesis and AUXIN1 (AUX1)/LIKE AUX1- and P-GLYCOPROTEIN/ATP-BINDING CASSETTE subfamily B-dependent transport is already present in several single-celled and colony-forming Chlorophyta species. In addition, our analysis of expressed sequence tag libraries from Coleochaete orbicularis and Spirogyra pratensis, green algae of the Streptophyta clade that are evolutionarily closer to the land plants than those of the Chlorophyta clade, revealed the presence of partial AUXIN RESPONSE FACTORs and/or AUXIN/INDOLE-3-ACETIC ACID proteins (the key factors in auxin signaling) and PIN-FORMED-like proteins (the best-characterized auxin-efflux carriers). While the identification of these possible AUXIN RESPONSE FACTOR- and AUXIN/INDOLE-3-ACETIC ACID precursors and putative PIN-FORMED orthologs calls for a deeper investigation of their evolution after sequencing more intermediate genomes, it emphasizes that the canonical auxin response machinery and auxin transport mechanisms were, at least in part, already present before plants "moved" to land habitats.
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Affiliation(s)
- Ive De Smet
- Department of Plant Systems Biology, Flanders Institute for Biotechnology, 9052 Ghent, Belgium.
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Palovaara J, Hallberg H, Stasolla C, Luit B, Hakman I. Expression of a gymnosperm PIN homologous gene correlates with auxin immunolocalization pattern at cotyledon formation and in demarcation of the procambium during Picea abies somatic embryo development and in seedling tissues. TREE PHYSIOLOGY 2010; 30:479-89. [PMID: 20129931 DOI: 10.1093/treephys/tpp126] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In seed plants, the body organization is established during embryogenesis and is uniform across gymnosperms and angiosperms, despite differences during early embryogeny. Evidence from angiosperms implicates the plant hormone auxin and its polar transport, mainly established by the PIN family of auxin efflux transporters, in the patterning of embryos. Here, PaPIN1 from Norway spruce (Picea abies [L.] Karst.), a gene widely expressed in conifer tissues and organs, was characterized and its expression and localization patterns were determined with reverse transcription polymerase chain reaction and in situ hybridization during somatic embryo development and in seedlings. PaPIN1 shares the predicted structure of other PIN proteins, but its central hydrophilic loop is longer than most PINs. In phylogenetic analyses, PaPIN1 clusters with Arabidopsis thaliana (L.) Heynh. PIN3, PIN4 and PIN7, but its expression pattern also suggests similarity to PIN1. The PaPIN1 expression signal was high in the protoderm of pre-cotyledonary embryos, but not if embryos were pre-treated with the auxin transport inhibitor N-1-naphthylphthalamic acid (NPA). This, together with a high auxin immunolocalization signal in this cell layer, suggests a role of PaPIN1 during cotyledon formation. At later stages, high PaPIN1 expression was observed in differentiating procambium, running from the tip of incipient cotyledons down through the embryo axis and to the root apical meristem (RAM), although the mode of RAM specification in conifer embryos differs from that of most angiosperms. Also, the PaPIN1 in situ signal was high in seedling root tips including root cap columella cells. The results thus suggest that PaPIN1 provides an ancient function associated with auxin transport and embryo pattern formation prior to the separation of angiosperms and gymnosperms, in spite of some morphological differences.
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Affiliation(s)
- Joakim Palovaara
- School of Natural Sciences, Linnaeus University, SE-391 82, Kalmar, Sweden
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Zazímalová E, Murphy AS, Yang H, Hoyerová K, Hosek P. Auxin transporters--why so many? Cold Spring Harb Perspect Biol 2010; 2:a001552. [PMID: 20300209 PMCID: PMC2829953 DOI: 10.1101/cshperspect.a001552] [Citation(s) in RCA: 253] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Interacting and coordinated auxin transporter actions in plants underlie a flexible network that mobilizes auxin in response to many developmental and environmental changes encountered by these sessile organisms. The independent but synergistic activity of individual transporters can be differentially regulated at various levels. This invests auxin transport mechanisms with robust functional redundancy and added auxin flow capacity when needed. An evolutionary perspective clarifies the roles of the different transporter groups in plant development. Mathematical and functional analysis of elements of auxin transport makes it possible to rationalize the relative contributions of members of the respective transporter classes to the localized auxin transport streams that then underlie both preprogrammed developmental changes and reactions to environmental stimuli.
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Affiliation(s)
- Eva Zazímalová
- Institute of Experimental Botany AS CR, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic.
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Pedmale UV, Celaya RB, Liscum E. Phototropism: mechanism and outcomes. THE ARABIDOPSIS BOOK 2010; 8:e0125. [PMID: 22303252 PMCID: PMC3244944 DOI: 10.1199/tab.0125] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Plants have evolved a wide variety of responses that allow them to adapt to the variable environmental conditions in which they find themselves growing. One such response is the phototropic response - the bending of a plant organ toward (stems and leaves) or away from (roots) a directional blue light source. Phototropism is one of several photoresponses of plants that afford mechanisms to alter their growth and development to changes in light intensity, quality and direction. Over recent decades much has been learned about the genetic, molecular and cell biological components involved in sensing and responding to phototropic stimuli. Many of these advances have been made through the utilization of Arabidopsis as a model for phototropic studies. Here we discuss such advances, as well as studies in other plant species where appropriate to the discussion of work in Arabidopsis.
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Affiliation(s)
- Ullas V. Pedmale
- Division of Biological Sciences and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211
| | - R. Brandon Celaya
- Division of Biological Sciences and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211
- Department of Molecular, Cellular and Developmental Biology, University of California — Los Angeles, 3206 Life Science Bldg, 621 Charles E Young Dr, Los Angeles, CA 90095
| | - Emmanuel Liscum
- Division of Biological Sciences and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211
- Address correspondence to
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Belin C, Megies C, Hauserová E, Lopez-Molina L. Abscisic acid represses growth of the Arabidopsis embryonic axis after germination by enhancing auxin signaling. THE PLANT CELL 2009; 21:2253-68. [PMID: 19666738 PMCID: PMC2751952 DOI: 10.1105/tpc.109.067702] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 07/14/2009] [Accepted: 07/25/2009] [Indexed: 05/18/2023]
Abstract
Under unfavorable environmental conditions, the stress phytohormone ABA inhibits the developmental transition from an embryo in a dry seed into a young seedling. We developed a genetic screen to isolate Arabidopsis thaliana mutants whose early seedling development is resistant to ABA. Here, we report the identification of a recessive mutation in AUXIN RESISTANT1 (AUX1), encoding a cellular auxin influx carrier. Although auxin is a major morphogenesis hormone in plants, little is known about ABA-auxin interactions during early seedling growth. We show that aux1 and pin2 mutants are insensitive to ABA-dependent repression of embryonic axis (hypocotyl and radicle) elongation. Genetic and physiological experiments show that this involves auxin transport to the embryonic axis elongation zone, where ABA enhances the activity of an auxin-responsive promoter. We propose that ABA represses embryonic axis elongation by potentiating auxin signaling in its elongation zone. This involves repression of the AUXIN INDUCIBLE (Aux/IAA) gene AXR2/IAA7, encoding a key component of ABA- and auxin-dependent responses during postgerminative growth.
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MESH Headings
- Abscisic Acid/pharmacology
- Arabidopsis/drug effects
- Arabidopsis/embryology
- Arabidopsis/genetics
- Arabidopsis/metabolism
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Arabidopsis Proteins/physiology
- Blotting, Northern
- Blotting, Western
- Chromatography, High Pressure Liquid
- Gene Expression Regulation, Plant/drug effects
- Gene Expression Regulation, Plant/genetics
- Gene Expression Regulation, Plant/physiology
- Germination/drug effects
- Germination/genetics
- Germination/physiology
- Indoleacetic Acids/metabolism
- Microscopy, Fluorescence
- Plant Growth Regulators/metabolism
- Plants, Genetically Modified/drug effects
- Plants, Genetically Modified/embryology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/metabolism
- Seedlings/drug effects
- Seedlings/embryology
- Seedlings/genetics
- Seedlings/metabolism
- Seeds/drug effects
- Seeds/embryology
- Seeds/genetics
- Seeds/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Signal Transduction/physiology
- Spectrometry, Mass, Electrospray Ionization
- Tandem Mass Spectrometry
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Affiliation(s)
- Christophe Belin
- Département de Biologie Végétale, Université de Genève, 1211 Genève 4, Switzerland
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Carrier DJ, Abu Bakar NT, Lawler K, Dorrian JM, Haider A, Bennett MJ, Kerr ID. Heterologous expression of a membrane-spanning auxin importer: implications for functional analyses of auxin transporters. INTERNATIONAL JOURNAL OF PLANT GENOMICS 2009; 2009:848145. [PMID: 19551158 PMCID: PMC2699565 DOI: 10.1155/2009/848145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 03/09/2009] [Accepted: 04/27/2009] [Indexed: 05/28/2023]
Abstract
Biochemical studies of plant auxin transporters in vivo are made difficult by the presence of multiple auxin transporters and auxin-interacting proteins. Furthermore, the expression level of most such transporters in plants is likely to be too low for purification and downstream functional analysis. Heterologous expression systems should address both of these issues. We have examined a number of such systems for their efficiency in expressing AUX1 from Arabidopsis thaliana. We find that a eukaryotic system based upon infection of insect cells with recombinant baculovirus provides a high level, easily scalable expression system capable of delivering a functional assay for AUX1. Furthermore, a transient transfection system in mammalian cells enables localization of AUX1 and AUX1-mediated transport of auxin to be investigated. In contrast, we were unable to utilise P. pastoris or L. lactis expression systems to reliably express AUX1.
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Affiliation(s)
- David John Carrier
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | | | - Karen Lawler
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - James Matthew Dorrian
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Ameena Haider
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Malcolm John Bennett
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Leics LE12 5RD, UK
| | - Ian Derek Kerr
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
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Titapiwatanakun B, Murphy AS. Post-transcriptional regulation of auxin transport proteins: cellular trafficking, protein phosphorylation, protein maturation, ubiquitination, and membrane composition. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:1093-107. [PMID: 18824505 DOI: 10.1093/jxb/ern240] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Auxin concentration gradients, established by polar transport of auxin, are essential for the establishment and maintenance of polar growth and morphological patterning. Three families of cellular transport proteins, PIN-formed (PIN), P-glycoprotein (ABCB/PGP), and AUXIN RESISTANT 1/LIKE AUX1 (AUX1/LAX), can independently and co-ordinately transport auxin in plants. Regulation of these proteins involves intricate and co-ordinated cellular processes, including protein-protein interactions, vesicular trafficking, protein phosphorylation, ubiquitination, and stabilization of the transporter complexes on the plasma membrane.
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47
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Mravec J, Kubeš M, Bielach A, Gaykova V, Petrášek J, Skůpa P, Chand S, Benková E, Zažímalová E, Friml J. Interaction of PIN and PGP transport mechanisms in auxin distribution-dependent development. Development 2008; 135:3345-54. [DOI: 10.1242/dev.021071] [Citation(s) in RCA: 179] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The signalling molecule auxin controls plant morphogenesis via its activity gradients, which are produced by intercellular auxin transport. Cellular auxin efflux is the rate-limiting step in this process and depends on PIN and phosphoglycoprotein (PGP) auxin transporters. Mutual roles for these proteins in auxin transport are unclear, as is the significance of their interactions for plant development. Here, we have analysed the importance of the functional interaction between PIN- and PGP-dependent auxin transport in development. We show by analysis of inducible overexpression lines that PINs and PGPs define distinct auxin transport mechanisms: both mediate auxin efflux but they play diverse developmental roles. Components of both systems are expressed during embryogenesis, organogenesis and tropisms, and they interact genetically in both synergistic and antagonistic fashions. A concerted action of PIN- and PGP-dependent efflux systems is required for asymmetric auxin distribution during these processes. We propose a model in which PGP-mediated efflux controls auxin levels in auxin channel-forming cells and, thus, auxin availability for PIN-dependent vectorial auxin movement.
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Affiliation(s)
- Jozef Mravec
- Department of Plant Systems Biology, VIB, and Department of Molecular Genetics, Ghent University, 9052 Gent, Belgium
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
| | - Martin Kubeš
- Institute for Experimental Botany, Academy of Sciences of the Czech Republic,Rozvojová 263, 165 02 Praha 6, Czech Republic
- Department of Plant Physiology, Faculty of Science, Charles University,Viničná 5, 128 44 Praha 2, Czech Republic
| | - Agnieszka Bielach
- Department of Plant Systems Biology, VIB, and Department of Molecular Genetics, Ghent University, 9052 Gent, Belgium
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
| | - Vassilena Gaykova
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
| | - Jan Petrášek
- Institute for Experimental Botany, Academy of Sciences of the Czech Republic,Rozvojová 263, 165 02 Praha 6, Czech Republic
- Department of Plant Physiology, Faculty of Science, Charles University,Viničná 5, 128 44 Praha 2, Czech Republic
| | - Petr Skůpa
- Institute for Experimental Botany, Academy of Sciences of the Czech Republic,Rozvojová 263, 165 02 Praha 6, Czech Republic
- Department of Plant Physiology, Faculty of Science, Charles University,Viničná 5, 128 44 Praha 2, Czech Republic
| | - Suresh Chand
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
| | - Eva Benková
- Department of Plant Systems Biology, VIB, and Department of Molecular Genetics, Ghent University, 9052 Gent, Belgium
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
| | - Eva Zažímalová
- Institute for Experimental Botany, Academy of Sciences of the Czech Republic,Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Jiří Friml
- Department of Plant Systems Biology, VIB, and Department of Molecular Genetics, Ghent University, 9052 Gent, Belgium
- Center for Plant Molecular Biology (ZMBP), University of Tübingen,D-72076 Tübingen, Germany
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Carrier DJ, Bakar NTA, Swarup R, Callaghan R, Napier RM, Bennett MJ, Kerr ID. The binding of auxin to the Arabidopsis auxin influx transporter AUX1. PLANT PHYSIOLOGY 2008; 148:529-35. [PMID: 18614710 PMCID: PMC2528085 DOI: 10.1104/pp.108.122044] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2008] [Accepted: 06/24/2008] [Indexed: 05/20/2023]
Abstract
The cellular import of the hormone auxin is a fundamental requirement for the generation of auxin gradients that control a multitude of plant developmental processes. The AUX/LAX family of auxin importers, exemplified by AUX1 from Arabidopsis (Arabidopsis thaliana), has been shown to mediate auxin import when expressed heterologously. The quantitative nature of the interaction between AUX1 and its transport substrate indole-3-acetic acid (IAA) is incompletely understood, and we sought to address this in the present investigation. We expressed AUX1 to high levels in a baculovirus expression system and prepared membrane fragments from baculovirus-infected insect cells. These membranes proved suitable for determination of the binding of IAA to AUX1 and enabled us to determine a K(d) of 2.6 mum, comparable with estimates for the K(m) for IAA transport. The efficacy of a number of auxin analogues and auxin transport inhibitors to displace IAA binding from AUX1 has also been determined and can be rationalized in terms of their physiological effects. Determination of the parameters describing the initial interaction between a plant transporter and its hormone ligand provides novel quantitative data for modeling auxin fluxes.
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Affiliation(s)
- David J Carrier
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom
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49
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Santelia D, Henrichs S, Vincenzetti V, Sauer M, Bigler L, Klein M, Bailly A, Lee Y, Friml J, Geisler M, Martinoia E. Flavonoids redirect PIN-mediated polar auxin fluxes during root gravitropic responses. J Biol Chem 2008; 283:31218-26. [PMID: 18718912 DOI: 10.1074/jbc.m710122200] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The rate, polarity, and symmetry of the flow of the plant hormone auxin are determined by the polar cellular localization of PIN-FORMED (PIN) auxin efflux carriers. Flavonoids, a class of secondary plant metabolites, have been suspected to modulate auxin transport and tropic responses. Nevertheless, the identity of specific flavonoid compounds involved and their molecular function and targets in vivo are essentially unknown. Here we show that the root elongation zone of agravitropic pin2/eir1/wav6/agr1 has an altered pattern and amount of flavonol glycosides. Application of nanomolar concentrations of flavonols to pin2 roots is sufficient to partially restore root gravitropism. By employing a quantitative cell biological approach, we demonstrate that flavonoids partially restore the formation of lateral auxin gradients in the absence of PIN2. Chemical complementation by flavonoids correlates with an asymmetric distribution of the PIN1 protein. pin2 complementation probably does not result from inhibition of auxin efflux, as supply of the auxin transport inhibitor N-1-naphthylphthalamic acid failed to restore pin2 gravitropism. We propose that flavonoids promote asymmetric PIN shifts during gravity stimulation, thus redirecting basipetal auxin streams necessary for root bending.
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Affiliation(s)
- Diana Santelia
- Laboratory of Molecular Plant Physiology, Institute of Plant Biology, University of Zürich, Zollikerstrasse 107, 8008 Zürich, Switzerland
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50
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Bailly A, Sovero V, Vincenzetti V, Santelia D, Bartnik D, Koenig BW, Mancuso S, Martinoia E, Geisler M. Modulation of P-glycoproteins by auxin transport inhibitors is mediated by interaction with immunophilins. J Biol Chem 2008; 283:21817-26. [PMID: 18499676 DOI: 10.1074/jbc.m709655200] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The immunophilin-like FKBP42 TWISTED DWARF1 (TWD1) has been shown to control plant development via the positive modulation of ABCB/P-glycoprotein (PGP)-mediated transport of the plant hormone auxin. TWD1 functionally interacts with two closely related proteins, ABCB1/PGP1 and ABCB19/PGP19/MDR1, both of which exhibit the ability to bind to and be inhibited by the synthetic auxin transport inhibitor N-1-naphylphtalamic acid (NPA). They are also inhibited by flavonoid compounds, which are suspected modulators of auxin transport. The mechanisms by which flavonoids and NPA interfere with auxin efflux components are unclear. We report here the specific disruption of PGP1-TWD1 interaction by NPA and flavonoids using bioluminescence resonance energy transfer with flavonoids functioning as a classical established inhibitor of mammalian and plant PGPs. Accordingly, TWD1 was shown to mediate modulation of PGP1 efflux activity by these auxin transport inhibitors. NPA bound to both PGP1 and TWD1 but was excluded from the PGP1-TWD1 complex expressed in yeast, suggesting a transient mode of action in planta. As a consequence, auxin fluxes and gravitropism in twd1 roots are less affected by NPA treatment, whereas TWD1 gain-of-function promotes root bending. Our data support a novel model for the mode of drug-mediated P-glycoprotein regulation mediated via protein-protein interaction with immunophilin-like TWD1.
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Affiliation(s)
- Aurélien Bailly
- Institute of Plant Biology and Zurich-Basel Plant Science Center, University of Zurich, Zurich, Switzerland
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