1
|
Deng B, Carter RA, Cheng Y, Liu Y, Eddy L, Wyss KM, Ucak-Astarlioglu MG, Luong DX, Gao X, JeBailey K, Kittrell C, Xu S, Jana D, Torres MA, Braam J, Tour JM. High-temperature electrothermal remediation of multi-pollutants in soil. Nat Commun 2023; 14:6371. [PMID: 37821460 PMCID: PMC10567823 DOI: 10.1038/s41467-023-41898-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 09/20/2023] [Indexed: 10/13/2023] Open
Abstract
Soil contamination is an environmental issue due to increasing anthropogenic activities. Existing processes for soil remediation suffer from long treatment time and lack generality because of different sources, occurrences, and properties of pollutants. Here, we report a high-temperature electrothermal process for rapid, water-free remediation of multiple pollutants in soil. The temperature of contaminated soil with carbon additives ramps up to 1000 to 3000 °C as needed within seconds via pulsed direct current input, enabling the vaporization of heavy metals like Cd, Hg, Pb, Co, Ni, and Cu, and graphitization of persistent organic pollutants like polycyclic aromatic hydrocarbons. The rapid treatment retains soil mineral constituents while increases infiltration rate and exchangeable nutrient supply, leading to soil fertilization and improved germination rates. We propose strategies for upscaling and field applications. Techno-economic analysis indicates the process holds the potential for being more energy-efficient and cost-effective compared to soil washing or thermal desorption.
Collapse
Affiliation(s)
- Bing Deng
- Department of Chemistry, Rice University, Houston, TX, 77005, USA.
| | - Robert A Carter
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Yi Cheng
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Yuan Liu
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Lucas Eddy
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
- Applied Physics Program, Rice University, Houston, TX, 77005, USA
- Smalley-Curl Institute, Rice University, Houston, TX, 77005, USA
| | - Kevin M Wyss
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Mine G Ucak-Astarlioglu
- Geotechnical and Structures Laboratory, U.S. Army Engineer Research & Development Center, Vicksburg, MS, 39180, USA
| | - Duy Xuan Luong
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
- Applied Physics Program, Rice University, Houston, TX, 77005, USA
| | - Xiaodong Gao
- Department of Earth, Environmental, & Planetary Sciences, Rice University, Houston, TX, 77005, USA
- Carbon Hub, Rice University, Houston, TX, 77005, USA
| | - Khalil JeBailey
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA
| | - Carter Kittrell
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Shichen Xu
- Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Debadrita Jana
- Department of Earth, Environmental, & Planetary Sciences, Rice University, Houston, TX, 77005, USA
| | - Mark Albert Torres
- Department of Earth, Environmental, & Planetary Sciences, Rice University, Houston, TX, 77005, USA
| | - Janet Braam
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - James M Tour
- Department of Chemistry, Rice University, Houston, TX, 77005, USA.
- Smalley-Curl Institute, Rice University, Houston, TX, 77005, USA.
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA.
- NanoCarbon Center and the Rice Advanced Materials Institute, Rice University, Houston, TX, 77005, USA.
| |
Collapse
|
2
|
Liu Y, Ahumada AL, Bayraktar E, Schwartz P, Chowdhury M, Shi S, Sebastian MM, Khant H, de Val N, Bayram NN, Zhang G, Vu TC, Jie Z, Jennings NB, Rodriguez-Aguayo C, Swain J, Stur E, Mangala LS, Wu Y, Nagaraju S, Ermias B, Li C, Lopez-Berestein G, Braam J, Sood AK. Enhancing oral delivery of plant-derived vesicles for colitis. J Control Release 2023; 357:472-483. [PMID: 37031740 PMCID: PMC10191613 DOI: 10.1016/j.jconrel.2023.03.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/11/2023]
Abstract
Plant-derived vesicles (PDVs) are attractive for therapeutic applications, including as potential nanocarriers. However, a concern with oral delivery of PDVs is whether they would remain intact in the gastrointestinal tract. We found that 82% of cabbage PDVs were destroyed under conditions mimicking the upper digestive tract. To overcome this limitation, we developed a delivery method whereby lyophilized Eudragit S100-coated cabbage PDVs were packaged into a capsule (Cap-cPDVs). Lyophilization and suspension of PDVs did not have an appreciable impact on PDV structure, number, or therapeutic effect. Additionally, packaging the lyophilized Eudragit S100-coated PDVs into capsules allowed them to pass through the upper gastrointestinal tract for delivery into the colon better than did suspension of PDVs in phosphate-buffered saline. Cap-cPDVs showed robust therapeutic effect in a dextran sulfate sodium-induced colitis mouse model. These findings could have broad implications for the use of PDVs as orally delivered nanocarriers of natural therapeutic plant compounds or other therapeutics.
Collapse
Affiliation(s)
- Yuan Liu
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of BioSciences, Rice University, Houston, TX 77005, USA.
| | - Adrian Lankenau Ahumada
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of BioSciences, Rice University, Houston, TX 77005, USA.
| | - Emine Bayraktar
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Paul Schwartz
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Mamur Chowdhury
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Sixiang Shi
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Manu M Sebastian
- Department of Veterinary Medicine and Surgery, Division of Basic Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Htet Khant
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Inc., Frederick, MD 21702, USA.
| | - Natalia de Val
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Inc., Frederick, MD 21702, USA.
| | - Nazende Nur Bayram
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Guodong Zhang
- Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Thanh Chung Vu
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Zuliang Jie
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Nicholas B Jennings
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Cristian Rodriguez-Aguayo
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Jody Swain
- Department of Veterinary Medicine and Surgery, Division of Basic Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Elaine Stur
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Lingegowda S Mangala
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Yutuan Wu
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Supriya Nagaraju
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Brooke Ermias
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Chun Li
- Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Gabriel Lopez-Berestein
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Janet Braam
- Department of BioSciences, Rice University, Houston, TX 77005, USA.
| | - Anil K Sood
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| |
Collapse
|
3
|
Liu Y, Lankenau-Ahumada A, Bayraktar E, Schwartz P, Chowdhury M, Shi S, Sebastian MM, Khant H, De Val N, Jie Z, Jennings NB, Rodriguez-Aguayo C, Swain J, Stur E, Mangala LS, Wu Y, Nagaraju S, Erimas B, Li C, Lopez-Berestein G, Braam J, Sood AK. Abstract 2720: Enhancing oral delivery of plant-derived vesicles. Cancer Res 2023. [DOI: 10.1158/1538-7445.am2023-2720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Abstract
Plant-derived vesicles (PDVs) were attractive for therapeutic applications, including as potential nanocarriers. However, a concern with oral delivery of PDVs is whether they would remain intact in the gastrointestinal tract. We found that 82% of cabbage PDVs were destroyed under conditions mimicking the upper digestive tract. To overcome this limitation, we developed a delivery method whereby lyophilized Eudragit S-100-coated cabbage PDVs were packaged into a capsule (Cap-cPDVs). Lyophilization and suspension of PDVs in phosphate-buffered saline did not have an appreciable effect on PDV structure, number of PDVs, or therapeutic effect. However, packaging the lyophilized Eudragit S-100-coated PDVs into capsules allowed them to pass through the upper gastrointestinal tract for delivery into the colon better than did suspension of PDVs in phosphate-buffered saline. Cap-cPDVs demonstrated robust therapeutic effect in a dextran sulfate sodium-induced colitis mouse model. These findings could have broad implications for oral delivery of PDVs.
Citation Format: Yuan Liu, Adrian Lankenau-Ahumada, Emine Bayraktar, Paul Schwartz, Mamur Chowdhury, Sixiang Shi, Manu M. Sebastian, Htet Khant, Natalia De Val, Zuliang Jie, Nicholas B. Jennings, Cristian Rodriguez-Aguayo, Jody Swain, Elaine Stur, Lingegowda S. Mangala, Yutuan Wu, Supriya Nagaraju, Brooke Erimas, Chun Li, Gabriel Lopez-Berestein, Janet Braam, Anil K. Sood. Enhancing oral delivery of plant-derived vesicles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2720.
Collapse
|
4
|
Brenya E, Pervin M, Chen ZH, Tissue DT, Johnson S, Braam J, Cazzonelli CI. Mechanical stress acclimation in plants: Linking hormones and somatic memory to thigmomorphogenesis. Plant Cell Environ 2022; 45:989-1010. [PMID: 34984703 DOI: 10.1111/pce.14252] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 12/03/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
A single event of mechanical stimulation is perceived by mechanoreceptors that transduce rapid transient signalling to regulate gene expression. Prolonged mechanical stress for days to weeks culminates in cellular changes that strengthen the plant architecture leading to thigmomorphogenesis. The convergence of multiple signalling pathways regulates mechanically induced tolerance to numerous biotic and abiotic stresses. Emerging evidence showed prolonged mechanical stimulation can modify the baseline level of gene expression in naive tissues, heighten gene expression, and prime disease resistance upon a subsequent pathogen encounter. The phenotypes of thigmomorphogenesis can persist throughout growth without continued stimulation, revealing somatic-stress memory. Epigenetic processes regulate TOUCH gene expression and could program transcriptional memory in differentiating cells to program thigmomorphogenesis. We discuss the early perception, gene regulatory and phytohormone pathways that facilitate thigmomorphogenesis and mechanical stress acclimation in Arabidopsis and other plant species. We provide insights regarding: (1) the regulatory mechanisms induced by single or prolonged events of mechanical stress, (2) how mechanical stress confers transcriptional memory to induce cross-acclimation to future stress, and (3) why thigmomorphogenesis might resemble an epigenetic phenomenon. Deeper knowledge of how prolonged mechanical stimulation programs somatic memory and primes defence acclimation could transform solutions to improve agricultural sustainability in stressful environments.
Collapse
Affiliation(s)
- Eric Brenya
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, USA
| | - Mahfuza Pervin
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
| | - Zhong-Hua Chen
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
- School of Science, Western Sydney University, Richmond, New South Wales, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
| | - Scott Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
| | - Janet Braam
- Department of Biosciences, Rice University, Houston, Texas, USA
| | - Christopher I Cazzonelli
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
| |
Collapse
|
5
|
Liu Y, Wu S, Koo Y, Yang A, Dai Y, Khant H, Osman SR, Chowdhury M, Wei H, Li Y, Court K, Hwang E, Wen Y, Dasari SK, Nguyen M, Tang ECC, Chehab EW, de Val N, Braam J, Sood AK. Characterization of and isolation methods for plant leaf nanovesicles and small extracellular vesicles. Nanomedicine 2020; 29:102271. [PMID: 32702466 DOI: 10.1016/j.nano.2020.102271] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 05/27/2020] [Accepted: 07/10/2020] [Indexed: 12/19/2022]
Abstract
Mammalian small extracellular vesicles (sEVs) can deliver diverse molecules to target cells. However, they are difficult to obtain in large quantities and can activate host immune responses. Plant-derived vesicles may help to overcome these challenges. We optimized isolation methods for two types of plant vesicles, nanovesicles from disrupted leaf and sEVs from the extracellular apoplastic space of Arabidopsis thaliana. Both preparations yielded intact vesicles of uniform size, and a mean membrane charge of approximately -25 mV. We also demonstrated applicability of these preparative methods using Brassicaceae vegetables. Proteomic analysis of a subset of vesicles with a density of 1.1-1.19 g mL-1 sheds light on the likely cellular origin and complexity of the vesicles. Both leaf nanovesicles and sEVs were taken up by cancer cells, with sEVs showing an approximately three-fold higher efficiency compared to leaf nanovesicles. These results support the potential of plant-derived vesicles as vehicles for therapeutic delivery.
Collapse
Affiliation(s)
- Yuan Liu
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX; BioSciences, Rice University, Houston, TX.
| | - Sherry Wu
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | | | - An Yang
- BioSciences, Rice University, Houston, TX; State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Yanwan Dai
- BioSciences, Rice University, Houston, TX.
| | - Htet Khant
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, Frederick, MD; Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Inc., Frederick, MD.
| | | | - Mamur Chowdhury
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | - Haichao Wei
- The Vivian L. Smith Department of Neurosurgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX.
| | - Yang Li
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | - Karem Court
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | | | - Yunfei Wen
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | - Santosh K Dasari
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| | | | | | | | - Natalia de Val
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, Frederick, MD; Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Inc., Frederick, MD.
| | | | - Anil K Sood
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
| |
Collapse
|
6
|
Kushwah S, Banasiak A, Nishikubo N, Derba-Maceluch M, Majda M, Endo S, Kumar V, Gomez L, Gorzsas A, McQueen-Mason S, Braam J, Sundberg B, Mellerowicz EJ. Arabidopsis XTH4 and XTH9 Contribute to Wood Cell Expansion and Secondary Wall Formation. Plant Physiol 2020; 182:1946-1965. [PMID: 32005783 PMCID: PMC7140944 DOI: 10.1104/pp.19.01529] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/21/2020] [Indexed: 05/05/2023]
Abstract
Xyloglucan is the major hemicellulose of dicotyledon primary cell walls, affecting the load-bearing framework with the participation of xyloglucan endo-transglycosylase/hydrolases (XTHs). We used loss- and gain-of function approaches to study functions of XTH4 and XTH9 abundantly expressed in cambial regions during secondary growth of Arabidopsis (Arabidopsis thaliana). In secondarily thickened hypocotyls, these enzymes had positive effects on vessel element expansion and fiber intrusive growth. They also stimulated secondary wall thickening but reduced secondary xylem production. Cell wall analyses of inflorescence stems revealed changes in lignin, cellulose, and matrix sugar composition indicating an overall increase in secondary versus primary walls in mutants, indicative of higher xylem production compared with the wild type (since secondary walls were thinner). Intriguingly, the number of secondary cell wall layers compared with the wild type was increased in xth9 and reduced in xth4, whereas the double mutant xth4x9 displayed an intermediate number of layers. These changes correlated with specific Raman signals from the walls, indicating changes in lignin and cellulose. Secondary walls were affected also in the interfascicular fibers, where neither XTH4 nor XTH9 was expressed, indicating that these effects were indirect. Transcripts involved in secondary wall biosynthesis and cell wall integrity sensing, including THESEUS1 and WALL ASSOCIATED KINASE2, were highly induced in the mutants, indicating that deficiency in XTH4 and XTH9 triggers cell wall integrity signaling, which, we propose, stimulates xylem cell production and modulates secondary wall thickening. Prominent effects of XTH4 and XTH9 on secondary xylem support the hypothesis that altered xyloglucan affects wood properties both directly and via cell wall integrity sensing.
Collapse
Affiliation(s)
- Sunita Kushwah
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Alicja Banasiak
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Nobuyuki Nishikubo
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Marta Derba-Maceluch
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Mateusz Majda
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Satoshi Endo
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Vikash Kumar
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Leonardo Gomez
- Center for Novel Agricultural Products, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Andras Gorzsas
- Department of Chemistry, Umeå University, SE-90187 Umea, Sweden
| | - Simon McQueen-Mason
- Center for Novel Agricultural Products, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Janet Braam
- Department of Bioscience, Rice University, Houston, Texas 77005-1827
| | - Björn Sundberg
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| | - Ewa J Mellerowicz
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, Swedish University of Agricultural Sciences, S901-83 Umea, Sweden
| |
Collapse
|
7
|
Dai Y, Ogilvie HA, Liu Y, Huang M, Markillie LM, Mitchell HD, Borrego EJ, Kolomiets MV, Gaffrey MJ, Orr G, Chehab EW, Mao WT, Braam J. Rosette core fungal resistance in Arabidopsis thaliana. Planta 2019; 250:1941-1953. [PMID: 31529398 DOI: 10.1007/s00425-019-03273-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
Unlike rosette leaves, the mature Arabidopsis rosette core can display full resistance to Botrytis cinerea revealing the importance for spatial and developmental aspects of plant fungal resistance. Arabidopsis thaliana is a model host to investigate plant defense against fungi. However, many of the reports investigating Arabidopsis fungal defense against the necrotrophic fungus, Botrytis cinerea, utilize rosette leaves as host tissue. Here we report organ-dependent differences in B. cinerea resistance of Arabidopsis. Although wild-type Arabidopsis rosette leaves mount a jasmonate-dependent defense that slows fungal growth, this defense is incapable of resisting fungal devastation. In contrast, as the fungus spreads through infected leaf petioles towards the plant center, or rosette core, there is a jasmonate- and age-dependent fungal penetration blockage into the rosette core. We report evidence for induced and preformed resistance in the rosette core, as direct rosette core inoculation can also result in resistance, but at a lower penetrance relative to infections that approach the core from infected leaf petioles. The Arabidopsis rosette core displays a distinct transcriptome relative to other plant organs, and BLADE ON PETIOLE (BOP) transcripts are abundant in the rosette core. The BOP genes, with known roles in abscission zone formation, are required for full Arabidopsis rosette core B. cinerea resistance, suggesting a possible role for BOP-dependent modifications that may help to restrict fungal susceptibility of the rosette core. Finally, we demonstrate that cabbage and cauliflower, common Brassicaceae crops, also display leaf susceptibility and rosette core resistance to B. cinerea that can involve leaf abscission. Thus, spatial and developmental aspects of plant host resistance play critical roles in resistance to necrotrophic fungal pathogens and are important to our understanding of plant defense mechanisms.
Collapse
Affiliation(s)
- Yanwan Dai
- BioSciences Department, Rice University, Houston, TX, 77005, USA
| | - Huw A Ogilvie
- Computer Science Department, Rice University, Houston, TX, 77005, USA
| | - Yuan Liu
- BioSciences Department, Rice University, Houston, TX, 77005, USA
| | - Michael Huang
- BioSciences Department, Rice University, Houston, TX, 77005, USA
| | - Lye Meng Markillie
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Hugh D Mitchell
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Eli J Borrego
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, 77843, USA
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, NY, 14623, USA
| | - Michael V Kolomiets
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, 77843, USA
| | - Matthew J Gaffrey
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Galya Orr
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - E Wassim Chehab
- BioSciences Department, Rice University, Houston, TX, 77005, USA
| | - Wan-Ting Mao
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Janet Braam
- BioSciences Department, Rice University, Houston, TX, 77005, USA.
| |
Collapse
|
8
|
Lei J, Jayaprakasha GK, Singh J, Uckoo R, Borrego EJ, Finlayson S, Kolomiets M, Patil BS, Braam J, Zhu-Salzman K. CIRCADIAN CLOCK-ASSOCIATED1 Controls Resistance to Aphids by Altering Indole Glucosinolate Production. Plant Physiol 2019; 181:1344-1359. [PMID: 31527087 PMCID: PMC6836836 DOI: 10.1104/pp.19.00676] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/04/2019] [Indexed: 05/07/2023]
Abstract
CIRCADIAN CLOCK-ASSOCIATED1 (CCA1), a well-known central circadian clock regulator, coordinates plant responses to environmental challenges. Its daily rhythmic expression in Arabidopsis (Arabidopsis thaliana) confers host resistance to the caterpillar Trichoplusia ni However, it is unclear whether CCA1 plays a role in defense against phloem sap-feeding aphids. In this study, we showed that green peach aphid (Myzus persicae) displayed an intrinsic circadian feeding rhythm. Under constant light, wild-type Columbia-0 (Col-0) Arabidopsis plants coentrained with aphids in the same light/dark cycles exhibited greater antixenotic activity than plants preentrained in the opposite cycle from the aphids. Consistently, circadian mutants cca1-1, cca1-11, lhy-21, ztl-1, ztl-4, and lux-2 suffered more severe damage than Col-0 plants when infested by aphids, suggesting that the Arabidopsis circadian clock plays a defensive role. However, the arrhythmic CCA1 overexpression line (CCA1-OX) displayed strong antixenotic and antibiotic activities despite its loss of circadian regulation. Aphids feeding on CCA1-OX plants exhibited lower reproduction and smaller body size and weight than those on Col-0. Apparently, CCA1 regulates both clock-dependent and -independent defense responses. Systematic investigation based on bioinformatics analyses indicated that resistance to aphids in CCA1-OX plants was due primarily to heightened basal indole glucosinolate levels. Interestingly, aphid feeding induced alternatively spliced intron-retaining CCA1a/b transcripts, which are normally expressed at low levels, whereas expression of the major fully spliced CCA1 transcript remained largely unchanged. We hypothesize that posttranscriptional modulation of CCA1 expression upon aphid infestation maximizes the potential of circadian-mediated defense and stress tolerance while ensuring normal plant development.
Collapse
Affiliation(s)
- Jiaxin Lei
- Department of Entomology, Texas A&M University, College Station, Texas 77843
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, Texas 77843
- Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, Texas 77843
| | | | - Jashbir Singh
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, Texas 77843
| | - Rammohan Uckoo
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, Texas 77843
| | - Eli J Borrego
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas 77843
| | - Scott Finlayson
- Department of Soil and Crop Sciences, Texas A&M University, College Station, Texas 77843
| | - Mike Kolomiets
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas 77843
| | - Bhimanagouda S Patil
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, Texas 77843
| | - Janet Braam
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005
| | - Keyan Zhu-Salzman
- Department of Entomology, Texas A&M University, College Station, Texas 77843
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, Texas 77843
- Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, Texas 77843
| |
Collapse
|
9
|
Martí Ruiz MC, Hubbard KE, Gardner MJ, Jung HJ, Aubry S, Hotta CT, Mohd-Noh NI, Robertson FC, Hearn TJ, Tsai YC, Dodd AN, Hannah M, Carré IA, Davies JM, Braam J, Webb AAR. Circadian oscillations of cytosolic free calcium regulate the Arabidopsis circadian clock. Nat Plants 2018; 4:690-698. [PMID: 30127410 PMCID: PMC6152895 DOI: 10.1038/s41477-018-0224-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 07/17/2018] [Indexed: 05/04/2023]
Abstract
In the last decade, the view of circadian oscillators has expanded from transcriptional feedback to incorporate post-transcriptional, post-translational, metabolic processes and ionic signalling. In plants and animals, there are circadian oscillations in the concentration of cytosolic free Ca2+ ([Ca2+]cyt), though their purpose has not been fully characterized. We investigated whether circadian oscillations of [Ca2+]cyt regulate the circadian oscillator of Arabidopsis thaliana. We report that in Arabidopsis, [Ca2+]cyt circadian oscillations can regulate circadian clock function through the Ca2+-dependent action of CALMODULIN-LIKE24 (CML24). Genetic analyses demonstrate a linkage between CML24 and the circadian oscillator, through pathways involving the circadian oscillator gene TIMING OF CAB2 EXPRESSION1 (TOC1).
Collapse
Affiliation(s)
| | - Katharine E Hubbard
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- School of Biological, Biomedical and Environmental Sciences, University of Hull, Hull, UK
| | - Michael J Gardner
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Hyun Ju Jung
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Sylvain Aubry
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Department for Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Carlos T Hotta
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Nur Izzati Mohd-Noh
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Department of Bioscience and Health Science, Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
| | - Fiona C Robertson
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Zimbabwe, Harare, Zimbabwe
| | - Timothy J Hearn
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Yu-Chang Tsai
- Biochemistry and Cell Biology, Rice University, Houston, TX, USA
| | - Antony N Dodd
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- School of Biological Sciences, Bristol Life Sciences Building, University of Bristol, Bristol, UK
| | - Matthew Hannah
- Bayer CropScience NV Innovation Center, Trait Discovery, Gent, Belgium
| | | | - Julia M Davies
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Janet Braam
- Biochemistry and Cell Biology, Rice University, Houston, TX, USA
| | - Alex A R Webb
- Department of Plant Sciences, University of Cambridge, Cambridge, UK.
| |
Collapse
|
10
|
|
11
|
Koo Y, Lukianova-Hleb EY, Pan J, Thompson SM, Lapotko DO, Braam J. In Planta Response of Arabidopsis to Photothermal Impact Mediated by Gold Nanoparticles. Small 2016; 12:623-630. [PMID: 26662357 DOI: 10.1002/smll.201502461] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Indexed: 06/05/2023]
Abstract
Biological responses to photothermal effects of gold nanoparticles (GNPs) have been demonstrated and employed for various applications in diverse systems except for one important class - plants. Here, the uptake of GNPs through Arabidopsis thaliana roots and translocation to leaves are reported. Successful plasmonic nanobubble generation and acoustic signal detection in planta is demonstrated. Furthermore, Arabidopsis leaves harboring GNPs and exposed to continuous laser or noncoherent light show elevated temperatures across the leaf surface and induced expression of heat-shock regulated genes. Overall, these results demonstrate that Arabidopsis can readily take up GNPs through the roots and translocate the particles to leaf tissues. Once within leaves, GNPs can act as photothermal agents for on-demand remote activation of localized biological processes in plants.
Collapse
Affiliation(s)
- Yeonjong Koo
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | | | - Joann Pan
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Sean M Thompson
- Department of Horticultural Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Dmitri O Lapotko
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
- Department of Physics and Astronomy, Rice University, Houston, TX, 77005, USA
| | - Janet Braam
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| |
Collapse
|
12
|
Liu JD, Goodspeed D, Sheng Z, Li B, Yang Y, Kliebenstein DJ, Braam J. Keeping the rhythm: light/dark cycles during postharvest storage preserve the tissue integrity and nutritional content of leafy plants. BMC Plant Biol 2015; 15:92. [PMID: 25879637 PMCID: PMC4396971 DOI: 10.1186/s12870-015-0474-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 03/16/2015] [Indexed: 05/05/2023]
Abstract
BACKGROUND The modular body structure of plants enables detached plant organs, such as postharvest fruits and vegetables, to maintain active responsiveness to environmental stimuli, including daily cycles of light and darkness. Twenty-four hour light/darkness cycles entrain plant circadian clock rhythms, which provide advantage to plants. Here, we tested whether green leafy vegetables gain longevity advantage by being stored under light/dark cycles designed to maintain biological rhythms. RESULTS Light/dark cycles during postharvest storage improved several aspects of plant tissue performance comparable to that provided by refrigeration. Tissue integrity, green coloration, and chlorophyll content were generally enhanced by cycling of light and darkness compared to constant light or darkness during storage. In addition, the levels of the phytonutrient glucosinolates in kale and cabbage remained at higher levels over time when the leaf tissue was stored under light/dark cycles. CONCLUSIONS Maintenance of the daily cycling of light and dark periods during postharvest storage may slow the decline of plant tissues, such as green leafy vegetables, improving not only appearance but also the health value of the crops through the maintenance of chlorophyll and phytochemical content after harvest.
Collapse
Affiliation(s)
- John D Liu
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
| | - Danielle Goodspeed
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
- Current Address: Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, 77030, USA.
| | - Zhengji Sheng
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
| | - Baohua Li
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA.
| | - Yiran Yang
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
| | - Daniel J Kliebenstein
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA.
- DynaMo Centre of Excellence, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Janet Braam
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
| |
Collapse
|
13
|
Koo Y, Wang J, Zhang Q, Zhu H, Chehab EW, Colvin VL, Alvarez PJJ, Braam J. Fluorescence reports intact quantum dot uptake into roots and translocation to leaves of Arabidopsis thaliana and subsequent ingestion by insect herbivores. Environ Sci Technol 2015; 49:626-632. [PMID: 25437125 DOI: 10.1021/es5050562] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We explored the impact of quantum dot (QD) coat characteristics on NP stability, uptake, and translocation in Arabidopsis thaliana, and subsequent transfer to primary consumers, Trichoplusia ni (T. ni). Arabidopsis was exposed to CdSe/CdZnS QDs with three different coatings: Poly(acrylic acid-ethylene glycol) (PAA-EG), polyethylenimine (PEI) and poly(maleic anhydride-alt-1-octadecene)-poly(ethylene glycol) (PMAO-PEG), which are anionic, cationic, and relatively neutral, respectively. PAA-EG-coated QDs were relatively stable and taken up from a hydroponic medium through both Arabidopsis leaf petioles and roots, without apparent aggregation, and showed generally uniform distribution in leaves. In contrast, PEI- and PMAO-PEG-coated QDs displayed destabilization in the hydroponic medium, and generated particulate fluorescence plant tissues, suggesting aggregation. PAA-EG QDs moved faster than PEI QDs through leaf petioles; however, 8-fold more cadmium accumulated in PEI QD-treated leaves than in those exposed to PAA-EG QDs, possibly due to PEI QD dissolution and direct metal uptake. T. ni caterpillars that fed on Arabidopsis exposed to QDs had reduced performance, and QD fluorescence was detected in both T. ni bodies and frass, demonstrating trophic transfer of intact QDs from plants to insects. Overall, this paper demonstrates that QD coat properties influence plant nanoparticle uptake and translocation and can impact transfer to herbivores.
Collapse
Affiliation(s)
- Yeonjong Koo
- Department of BioSciences, ‡Department of Civil & Environmental Engineering, and §Department of Chemistry, Rice University , Houston, Texas 77005, United States
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Zhu XF, Wan JX, Sun Y, Shi YZ, Braam J, Li GX, Zheng SJ. Xyloglucan Endotransglucosylase-Hydrolase17 Interacts with Xyloglucan Endotransglucosylase-Hydrolase31 to Confer Xyloglucan Endotransglucosylase Action and Affect Aluminum Sensitivity in Arabidopsis. Plant Physiol 2014; 165:1566-1574. [PMID: 24948835 PMCID: PMC4119039 DOI: 10.1104/pp.114.243790] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 06/16/2014] [Indexed: 05/20/2023]
Abstract
Previously, we reported that although the Arabidopsis (Arabidopsis thaliana) Xyloglucan Endotransglucosylase-Hydrolase31 (XTH31) has predominately xyloglucan endohydrolase activity in vitro, loss of XTH31 results in remarkably reduced in vivo xyloglucan endotransglucosylase (XET) action and enhanced Al resistance. Here, we report that XTH17, predicted to have XET activity, binds XTH31 in yeast (Saccharomyces cerevisiae) two-hybrid and coimmunoprecipitations assays and that this interaction may be required for XTH17 XET activity in planta. XTH17 and XTH31 may be colocalized in plant cells because tagged XTH17 fusion proteins, like XTH31 fusion proteins, appear to target to the plasma membrane. XTH17 expression, like that of XTH31, was substantially reduced in the presence of aluminum (Al), even at concentrations as low as 10 µm for 24 h or 25 µm for just 30 min. Agrobacterium tumefaciens-mediated transfer DNA insertion mutant of XTH17, xth17, showed low XET action and had moderately shorter roots than the wild type but was more Al resistant than the wild type. Similar to xth31, xth17 had low hemicellulose content and retained less Al in the cell wall. These data suggest a model whereby XTH17 and XTH31 may exist as a dimer at the plasma membrane to confer in vivo XET action, which modulates cell wall Al-binding capacity and thereby affects Al sensitivity in Arabidopsis.
Collapse
Affiliation(s)
- Xiao Fang Zhu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Jiang Xue Wan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Ying Sun
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Yuan Zhi Shi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Janet Braam
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Gui Xin Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| | - Shao Jian Zheng
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences (X.F.Z., J.X.W., Y.S, S.J.Z.), and College of Agronomy and Biotechnology (G.X.L.), Zhejiang University, Hangzhou 310058, China;Department of Plant Physiology and Nutrition, Tea Research Institute, Chinese Academy of Agricultural Sciences, the Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China (Y.Z.S.); andBiochemistry and Cell Biology, Rice University, Houston, Texas 77005 (J.B.)
| |
Collapse
|
15
|
Wang J, Yang Y, Zhu H, Braam J, Schnoor JL, Alvarez PJJ. Uptake, translocation, and transformation of quantum dots with cationic versus anionic coatings by Populus deltoides × nigra cuttings. Environ Sci Technol 2014; 48:6754-6762. [PMID: 24870363 DOI: 10.1021/es501425r] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Manipulation of the organic coatings of nanoparticles such as quantum dots (QDs) to enhance specific applications may also affect their interaction and uptake by different organisms. In this study, poplar trees (Populus deltoides × nigra) were exposed hydroponically to 50-nM CdSe/CdZnS QDs coated with cationic polyethylenimine (PEI) (35.3 ± 6.6 nm) or poly(ethylene glycol) of anionic poly(acrylic acid) (PAA-EG) (19.5 ± 7.2 nm) to discern how coating charge affects nanoparticle uptake, translocation, and transformation within woody plants. Uptake of cationic PEI-QDs was 10 times faster despite their larger hydrodynamic size and higher extent of aggregation (17 times larger than PAA-EG-QDs after 11-day incubation in the hydroponic medium), possibly due to electrostatic attraction to the negatively charged root cell wall. QDs cores aggregated upon root uptake, and their translocation to poplar shoots (negligible for PAA-EG-QDs and 0.7 ng Cd/mg stem for PEI-QDs) was likely limited by the endodermis. After 2-day exposure, PEI and PAA-EG coatings were likely degraded from the internalized QDs inside the plant, leading to the aggregation of the metallic cores and a "red-shift" of fluorescence. The fluorescence of PEI-QD aggregates was stable inside the roots through the 11-day exposure period. In contrast, the PAA-EG-QD aggregates lost fluorescence inside the plant after 11 days probably due to destabilization of the coating, even though these QDs were stable in the hydroponic solution. Overall, these results highlight the importance of coating properties in the rate and extent to which nanoparticles are assimilated by plants and potentially introduced into food webs.
Collapse
Affiliation(s)
- Jing Wang
- Department of Civil & Environmental Engineering, ‡Department of Chemistry, and §Department of Biochemistry & Cell Biology, Rice University , Houston, Texas 77005, United States
| | | | | | | | | | | |
Collapse
|
16
|
Kim S, Schlicke H, Van Ree K, Karvonen K, Subramaniam A, Richter A, Grimm B, Braam J. Arabidopsis chlorophyll biosynthesis: an essential balance between the methylerythritol phosphate and tetrapyrrole pathways. Plant Cell 2013; 25:4984-93. [PMID: 24363312 PMCID: PMC3904000 DOI: 10.1105/tpc.113.119172] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 11/16/2013] [Accepted: 11/29/2013] [Indexed: 05/20/2023]
Abstract
Chlorophyll, essential for photosynthesis, is composed of a chlorin ring and a geranylgeranyl diphosphate (GGPP)-derived isoprenoid, which are generated by the tetrapyrrole and methylerythritol phosphate (MEP) biosynthesis pathways, respectively. Although a functional MEP pathway is essential for plant viability, the underlying basis of the requirement has been unclear. We hypothesized that MEP pathway inhibition is lethal because a reduction in GGPP availability results in a stoichiometric imbalance in tetrapyrrolic chlorophyll precursors, which can cause deadly photooxidative stress. Consistent with this hypothesis, lethality of MEP pathway inhibition in Arabidopsis thaliana by fosmidomycin (FSM) is light dependent, and toxicity of MEP pathway inhibition is reduced by genetic and chemical impairment of the tetrapyrrole pathway. In addition, FSM treatment causes a transient accumulation of chlorophyllide and transcripts associated with singlet oxygen-induced stress. Furthermore, exogenous provision of the phytol molecule reduces FSM toxicity when the phytol can be modified for chlorophyll incorporation. These data provide an explanation for FSM toxicity and thereby provide enhanced understanding of the mechanisms of FSM resistance. This insight into MEP pathway inhibition consequences underlines the risk plants undertake to synthesize chlorophyll and suggests the existence of regulation, possibly involving chloroplast-to-nucleus retrograde signaling, that may monitor and maintain balance of chlorophyll precursor synthesis.
Collapse
Affiliation(s)
- Se Kim
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
| | - Hagen Schlicke
- Institute of Biology, Department of Plant Physiology, Humboldt University, 10115 Berlin, Germany
| | - Kalie Van Ree
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
| | - Kristine Karvonen
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
| | - Anant Subramaniam
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
| | - Andreas Richter
- Institute of Biology, Department of Plant Physiology, Humboldt University, 10115 Berlin, Germany
| | - Bernhard Grimm
- Institute of Biology, Department of Plant Physiology, Humboldt University, 10115 Berlin, Germany
| | - Janet Braam
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
- Address correspondence to
| |
Collapse
|
17
|
Zhu XF, Lei GJ, Wang ZW, Shi YZ, Braam J, Li GX, Zheng SJ. Coordination between apoplastic and symplastic detoxification confers plant aluminum resistance. Plant Physiol 2013; 162:1947-55. [PMID: 23776189 PMCID: PMC3729773 DOI: 10.1104/pp.113.219147] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 06/14/2013] [Indexed: 05/18/2023]
Abstract
Whether aluminum toxicity is an apoplastic or symplastic phenomenon is still a matter of debate. Here, we found that three auxin overproducing mutants, yucca, the recessive mutant superroot2, and superroot1 had increased aluminum sensitivity, while a transfer DNA insertion mutant, xyloglucan endotransglucosylase/hydrolases15 (xth15), showed enhanced aluminum resistance, accompanied by low endogenous indole-3-acetic acid levels, implying that auxin may be involved in plant responses to aluminum stress. We used yucca and xth15 mutants for further study. The two mutants accumulated similar total aluminum in roots and had significantly reduced cell wall aluminum and increased symplastic aluminum content relative to the wild-type ecotype Columbia, indicating that altered aluminum levels in the symplast or cell wall cannot fully explain the differential aluminum resistance of these two mutants. The expression of Al sensitive1 (ALS1), a gene that functions in aluminum redistribution between the cytoplasm and vacuole and contributes to symplastic aluminum detoxification, was less abundant in yucca and more abundant in xth15 than the wild type, consistent with possible ALS1 function conferring altered aluminum sensitivity in the two mutants. Consistent with the idea that xth15 can tolerate more symplastic aluminum because of possible ALS1 targeting to the vacuole, morin staining of yucca root tip sections showed more aluminum accumulation in the cytosol than in the wild type, and xth15 showed reduced morin staining of cytosolic aluminum, even though yucca and xth15 had similar overall symplastic aluminum content. Exogenous application of an active auxin analog, naphthylacetic acid, to the wild type mimicked the aluminum sensitivity and distribution phenotypes of yucca, verifying that auxin may regulate aluminum distribution in cells. Together, these data demonstrate that auxin negatively regulates aluminum tolerance through altering ALS1 expression and aluminum distribution within plant cells, and plants must coordinate exclusion and internal detoxification to reduce aluminum toxicity effectively.
Collapse
|
18
|
Goodspeed D, Liu JD, Chehab EW, Sheng Z, Francisco M, Kliebenstein DJ, Braam J. Postharvest circadian entrainment enhances crop pest resistance and phytochemical cycling. Curr Biol 2013; 23:1235-41. [PMID: 23791724 DOI: 10.1016/j.cub.2013.05.034] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 04/26/2013] [Accepted: 05/20/2013] [Indexed: 12/14/2022]
Abstract
The modular design of plants enables individual plant organs to manifest autonomous functions and continue aspects of metabolism, such as respiration, even after separation from the parent plant. Therefore, we hypothesized that harvested vegetables and fruits may retain capacity to perceive and respond to external stimuli. For example, the fitness advantage of plant circadian clock function is recognized; however, whether the clock continues to influence postharvest physiology is unclear. Here we demonstrate that the circadian clock of postharvest cabbage (Brassica oleracea) is entrainable by light-dark cycles and results in enhanced herbivore resistance. In addition, entrainment of Arabidopsis plants and postharvest cabbage causes cyclical accumulation of metabolites that function in plant defense; in edible crops, these metabolites also have potent anticancer properties. Finally, we show that the phenomena of postharvest entrainment and enhanced herbivore resistance are widespread among diverse crops. Therefore, sustained clock entrainment of postharvest crops may be a simple mechanism to promote pest resistance and nutritional value of plant-derived food.
Collapse
Affiliation(s)
- Danielle Goodspeed
- Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | | | | | | | | | | | | |
Collapse
|
19
|
Wang J, Koo Y, Alexander A, Yang Y, Westerhof S, Zhang Q, Schnoor JL, Colvin VL, Braam J, Alvarez PJJ. Phytostimulation of poplars and Arabidopsis exposed to silver nanoparticles and Ag⁺ at sublethal concentrations. Environ Sci Technol 2013; 47:5442-9. [PMID: 23631766 DOI: 10.1021/es4004334] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The increasing likelihood of silver nanoparticle (AgNP) releases to the environment highlights the importance of understanding AgNP interactions with plants, which are cornerstones of most ecosystems. In this study, poplars (Populus deltoides × nigra) and Arabidopsis thaliana were exposed hydroponically to nanoparticles of different sizes (PEG-coated 5 and 10 nm AgNPs, and carbon-coated 25 nm AgNPs) or silver ions (Ag(+), added as AgNO₃) at a wide range of concentrations (0.01 to 100 mg/L). Whereas all forms of silver were phytotoxic above a specific concentration, a stimulatory effect was observed on root elongation, fresh weight, and evapotranspiration of both plants at a narrow range of sublethal concentrations (e.g., 1 mg/L of 25 nm AgNPs for poplar). Plants were most susceptible to the toxic effects of Ag(+) (1 mg/L for poplar, 0.05 mg/L for Arabidopsis), but AgNPs also showed some toxicity at higher concentrations (e.g., 100 mg/L of 25 nm AgNPs for poplar, 1 mg/L of 5 nm AgNPs for Arabidopsis) and this susceptibility increased with decreasing AgNP size. Both poplars and Arabidopsis accumulated silver, but silver distribution in shoot organs varied between plant species. Arabidopsis accumulated silver primarily in leaves (at 10-fold higher concentrations than in the stem or flower tissues), whereas poplars accumulated silver at similar concentrations in leaves and stems. Within the particle subinhibitory concentration range, silver accumulation in poplar tissues increased with exposure concentration and with smaller AgNP size. However, compared to larger AgNPs, the faster silver uptake associated with smaller AgNPs was offset by their toxic effect on evapotranspiration, which was exerted at lower concentrations (e.g., 1 mg/L of 5 nm AgNPs for poplar). Overall, the observed phytostimulatory effects preclude generalizations about the phytotoxicity of AgNPs and encourage further mechanistic research.
Collapse
Affiliation(s)
- Jing Wang
- Department of Civil & Environmental Engineering, Rice University, Houston, Texas 77005, United States
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Zhao Y, Liu W, Xu YP, Cao JY, Braam J, Cai XZ. Genome-wide identification and functional analyses of calmodulin genes in Solanaceous species. BMC Plant Biol 2013; 13:70. [PMID: 23621884 PMCID: PMC3751459 DOI: 10.1186/1471-2229-13-70] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/24/2013] [Indexed: 05/21/2023]
Abstract
BACKGROUND Calmodulin (CaM) is a major calcium sensor in all eukaryotes. It binds calcium and modulates the activity of a wide range of downstream proteins in response to calcium signals. However, little is known about the CaM gene family in Solanaceous species, including the economically important species, tomato (Solanum lycopersicum), and the gene silencing model plant, Nicotiana benthamiana. Moreover, the potential function of CaM in plant disease resistance remains largely unclear. RESULTS We performed genome-wide identification of CaM gene families in Solanaceous species. Employing bioinformatics approaches, multiple full-length CaM genes were identified from tomato, N. benthamiana and potato (S. tuberosum) genomes, with tomato having 6 CaM genes, N. benthamiana having 7 CaM genes, and potato having 4 CaM genes. Sequence comparison analyses showed that three tomato genes, SlCaM3/4/5, two potato genes StCaM2/3, and two sets of N. benthamiana genes, NbCaM1/2/3/4 and NbCaM5/6, encode identical CaM proteins, yet the genes contain different intron/exon organization and are located on different chromosomes. Further sequence comparisons and gene structural and phylogenetic analyses reveal that Solanaceous species gained a new group of CaM genes during evolution. These new CaM genes are unusual in that they contain three introns in contrast to only a single intron typical of known CaM genes in plants. The tomato CaM (SlCaM) genes were found to be expressed in all organs. Prediction of cis-acting elements in 5' upstream sequences and expression analyses demonstrated that SlCaM genes have potential to be highly responsive to a variety of biotic and abiotic stimuli. Additionally, silencing of SlCaM2 and SlCaM6 altered expression of a set of signaling and defense-related genes and resulted in significantly lower resistance to Tobacco rattle virus and the oomycete pathogen, Pythium aphanidermatum. CONCLUSIONS The CaM gene families in the Solanaceous species tomato, N. benthamiana and potato were identified through a genome-wide analysis. All three plant species harbor a small set of genes that encode identical CaM proteins, which may manifest a strategy of plants to retain redundancy or enhanced quantitative gene function. In addition, Solanaceous species have evolved one new group of CaM genes during evolution. CaM genes play important roles in plant disease resistance to a variety of pathogens.
Collapse
Affiliation(s)
- Yuan Zhao
- Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China
| | - Wei Liu
- Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China
| | - You-Ping Xu
- Center of Analysis and Measurement, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China
| | - Jia-Yi Cao
- Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China
| | - Janet Braam
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | - Xin-Zhong Cai
- Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China
| |
Collapse
|
21
|
Goodspeed D, Chehab EW, Covington MF, Braam J. Circadian control of jasmonates and salicylates: the clock role in plant defense. Plant Signal Behav 2013; 8:e23123. [PMID: 23299428 PMCID: PMC3657008 DOI: 10.4161/psb.23123] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Plants have evolved robust mechanisms to perceive and respond to diverse environmental stimuli. The plant phytohormones jasmonates and salicylates play key roles in activating biotic stress response pathways. Recent findings demonstrate that basal levels of both jasmonates and salicylates in Arabidopsis are under the control of the circadian clock and that clock-controlled jasmonate accumulation may underlie clock- and jasmonate-dependent enhanced resistance of Arabidopsis to Trichoplusia ni (cabbage looper), a generalist herbivore. Here we summarize these findings and provide further evidence that a functional plant circadian clock is required for optimal herbivore defense in Arabidopsis. When given a choice to feed on wild-type plants or arrhythmic transgenics, T. ni prefer plants lacking robust circadian rhythms. Altogether these data provide strong evidence for circadian clock enabling anticipation of herbivore attack and thus contributing to overall plant fitness.
Collapse
|
22
|
Tsai YC, Koo Y, Delk NA, Gehl B, Braam J. Calmodulin-related CML24 interacts with ATG4b and affects autophagy progression in Arabidopsis. Plant J 2013; 73:325-35. [PMID: 23039100 DOI: 10.1111/tpj.12043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/20/2012] [Accepted: 10/02/2012] [Indexed: 05/10/2023]
Abstract
Plants encounter environmental stress challenges that are distinct from those of other eukaryotes because of their relative immobility. Therefore, plants may have evolved distinct regulatory mechanisms for conserved cellular functions. Plants, like other eukaryotes, share aspects of both calcium- and calmodulin-based cellular signaling and the autophagic process of cellular renewal. Here, we report a novel function for an Arabidopsis calmodulin-related protein, CML24, and insight into ATG4-regulated autophagy. CML24 interacts with ATG4b in yeast two-hybrid, in vitro pull-down and transient tobacco cell transformation assays. Mutants with missense mutations in CML24 have aberrant ATG4 activity patterns in in vitro extract assays, altered ATG8 accumulation levels, an altered pattern of GFP-ATG8-decorated cellular structures, and altered recovery from darkness-induced starvation. Together, these results support the conclusion that CML24 affects autophagy progression through interactions with ATG4.
Collapse
Affiliation(s)
- Yu-Chang Tsai
- Biochemistry and Cell Biology, Rice University, Houston, TX, 77005-1892, USA
| | - Yeonjong Koo
- Biochemistry and Cell Biology, Rice University, Houston, TX, 77005-1892, USA
| | - Nikkí A Delk
- Biochemistry and Cell Biology, Rice University, Houston, TX, 77005-1892, USA
| | - Bernadette Gehl
- Biochemistry and Cell Biology, Rice University, Houston, TX, 77005-1892, USA
| | - Janet Braam
- Biochemistry and Cell Biology, Rice University, Houston, TX, 77005-1892, USA
| |
Collapse
|
23
|
Zhu XF, Shi YZ, Lei GJ, Fry SC, Zhang BC, Zhou YH, Braam J, Jiang T, Xu XY, Mao CZ, Pan YJ, Yang JL, Wu P, Zheng SJ. XTH31, encoding an in vitro XEH/XET-active enzyme, regulates aluminum sensitivity by modulating in vivo XET action, cell wall xyloglucan content, and aluminum binding capacity in Arabidopsis. Plant Cell 2012; 24:4731-47. [PMID: 23204407 PMCID: PMC3531863 DOI: 10.1105/tpc.112.106039] [Citation(s) in RCA: 169] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 10/08/2012] [Accepted: 10/20/2012] [Indexed: 05/18/2023]
Abstract
Xyloglucan endohydrolase (XEH) and xyloglucan endotransglucosylase (XET) activities, encoded by xyloglucan endotransglucosylase-hydrolase (XTH) genes, are involved in cell wall extension by cutting or cutting and rejoining xyloglucan chains, respectively. However, the physiological significance of this biochemical activity remains incompletely understood. Here, we find that an XTH31 T-DNA insertion mutant, xth31, is more Al resistant than the wild type. XTH31 is bound to the plasma membrane and the encoding gene is expressed in the root elongation zone and in nascent leaves, suggesting a role in cell expansion. XTH31 transcript accumulation is strongly downregulated by Al treatment. XTH31 expression in yeast yields a protein with an in vitro XEH:XET activity ratio of >5000:1. xth31 accumulates significantly less Al in the root apex and cell wall, shows remarkably lower in vivo XET action and extractable XET activity, has a lower xyloglucan content, and exhibits slower elongation. An exogenous supply of xyloglucan significantly ameliorates Al toxicity by reducing Al accumulation in the roots, owing to the formation of an Al-xyloglucan complex in the medium, as verified by an obvious change in chemical shift of (27)Al-NMR. Taken together, the data indicate that XTH31 affects Al sensitivity by modulating cell wall xyloglucan content and Al binding capacity.
Collapse
Affiliation(s)
- Xiao Fang Zhu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuan Zhi Shi
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, China
- Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, University of Edinburgh, Edinburgh EH9 3JH, United Kingdom
| | - Gui Jie Lei
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Stephen C. Fry
- Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, University of Edinburgh, Edinburgh EH9 3JH, United Kingdom
| | - Bao Cai Zhang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi Hua Zhou
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Janet Braam
- Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892
| | - Tao Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiao Yan Xu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Chuan Zao Mao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuan Jiang Pan
- Department of Chemistry, Zhejiang University, Hangzhou 310007, China
| | - Jian Li Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ping Wu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shao Jian Zheng
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
24
|
Abstract
Nitric oxide signals diverse responses in animals and plants. Whereas nitric oxide synthesis mechanisms in animals are well understood, how nitric oxide is synthesized and regulated in plants remains controversial. NOA1 is a circularly permuted GTPase that is important for chloroplast function and is implicated in nitric oxide synthesis. However, the reported consequences of a null mutation in NOA1 are inconsistent. Whereas some studies indicate that the noa1 mutant has severe reductions in nitric oxide accumulation, others report that nitric oxide levels are indistinguishable between noa1 and the wild type. Here, we identify a correlation between the reported ability of noa1 to accumulate nitric oxide with growth on sucrose-supplemented media. We report that noa1 accumulates both basal and salicylic acid-induced nitric oxide only when grown on media containing sucrose. In contrast, nitric oxide accumulation in wild type is largely insensitive to sucrose supplementation. When grown in the absence of sucrose, noa1 has low fumarate, pale green leaves, slow growth and reduced chlorophyll content. These phenotypes are consistent with a defect in chloroplast-derived photosynthate production and are largely rescued by sucrose supplementation. We conclude that NOA1 has a primary role in chloroplast function and that its effects on the accumulation of nitric oxide are likely to be indirect.
Collapse
Affiliation(s)
- Kalie Van Ree
- Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | | | | | | | | |
Collapse
|
25
|
Chehab EW, Kim S, Savchenko T, Kliebenstein D, Dehesh K, Braam J. Intronic T-DNA insertion renders Arabidopsis opr3 a conditional jasmonic acid-producing mutant. Plant Physiol 2011; 156:770-8. [PMID: 21487047 PMCID: PMC3177274 DOI: 10.1104/pp.111.174169] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 04/08/2011] [Indexed: 05/17/2023]
Abstract
Jasmonic acid and its derived metabolites (JAs) orchestrate plant defense against insects and fungi. 12-Oxo-phytodienoic acid (OPDA), a JA precursor, has also been implicated in plant defense. We sought to define JAs and OPDA functions through comparative defense susceptibility characteristics of three Arabidopsis (Arabidopsis thaliana) genotypes: aos, lacking JAs and OPDA; opda reductase3 (opr3), deficient in JA production but can accumulate OPDA; and transgenics that overexpress OPR3. opr3, like aos, is susceptible to cabbage loopers (Trichoplusia ni) but, relative to aos, opr3 has enhanced resistance to a necrotrophic fungus. Gas chromatography-mass spectrometry reveals that opr3 produces OPDA but no detectable JAs following wounding and looper infestation; unexpectedly, substantial levels of JAs accumulate in opr3 upon fungal infection. Full-length OPR3 transcripts accumulate in fungal-infected opr3, potentially through splicing of the T-DNA containing intron. Fungal resistance correlates with levels of JAs not OPDA; therefore, opr3 resistance to some pests is likely due to JA accumulation, and signaling activities ascribed to OPDA should be reassessed because opr3 can produce JAs. Together these data (1) reinforce the primary role JAs play in plant defense against insects and necrotrophic fungi, (2) argue for a reassessment of signaling activities ascribed to OPDA, and (3) provide evidence that mutants with intron insertions can retain gene function.
Collapse
|
26
|
Lee CW, Mahendra S, Zodrow K, Li D, Tsai YC, Braam J, Alvarez PJJ. Developmental phytotoxicity of metal oxide nanoparticles to Arabidopsis thaliana. Environ Toxicol Chem 2010; 29:669-75. [PMID: 20821493 DOI: 10.1002/etc.58] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Phytotoxicity is an important consideration to understand the potential environmental impacts of manufactured nanomaterials. Here, we report on the effects of four metal oxide nanoparticles, aluminum oxide (nAl(2)O(3)), silicon dioxide (nSiO(2)), magnetite (nFe(3)O(4)), and zinc oxide (nZnO), on the development of Arabidopsis thaliana (Mouse-ear cress). Three toxicity indicators (seed germination, root elongation, and number of leaves) were quantified following exposure to each nanoparticle at three concentrations: 400, 2,000, and 4,000 mg/L. Among these particles, nZnO was most phytotoxic, followed by nFe(3)O(4), nSiO(2), and nAl(2)O(3), which was not toxic. Consequently, nZnO was further studied to discern the importance of particle size and zinc dissolution as toxicity determinants. Soluble zinc concentrations in nanoparticle suspensions were 33-fold lower than the minimum inhibitory concentration of dissolved zinc salt (ZnCl(2)), indicating that zinc dissolution could not solely account for the observed toxicity. Inhibition of seed germination by ZnO depended on particle size, with nanoparticles exerting higher toxicity than larger (micron-sized) particles at equivalent concentrations. Overall, this study shows that direct exposure to nanoparticles significantly contributed to phytotoxicity and underscores the need for eco-responsible disposal of wastes and sludge containing metal oxide nanoparticles.
Collapse
Affiliation(s)
- Chang Woo Lee
- Department of Civil and Environmental Engineering, Rice University, MS-317, Houston, Texas 77005, USA
| | | | | | | | | | | | | |
Collapse
|
27
|
Lee CW, Mahendra S, Zodrow K, Li D, Tsai YC, Braam J, Alvarez PJJ. Developmental phytotoxicity of metal oxide nanoparticles to Arabidopsis thaliana. Environ Toxicol Chem 2010; 29:669-675. [PMID: 20821493 DOI: 10.1002/etc.234] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Phytotoxicity is an important consideration to understand the potential environmental impacts of manufactured nanomaterials. Here, we report on the effects of four metal oxide nanoparticles, aluminum oxide (nAl(2)O(3)), silicon dioxide (nSiO(2)), magnetite (nFe(3)O(4)), and zinc oxide (nZnO), on the development of Arabidopsis thaliana (Mouse-ear cress). Three toxicity indicators (seed germination, root elongation, and number of leaves) were quantified following exposure to each nanoparticle at three concentrations: 400, 2,000, and 4,000 mg/L. Among these particles, nZnO was most phytotoxic, followed by nFe(3)O(4), nSiO(2), and nAl(2)O(3), which was not toxic. Consequently, nZnO was further studied to discern the importance of particle size and zinc dissolution as toxicity determinants. Soluble zinc concentrations in nanoparticle suspensions were 33-fold lower than the minimum inhibitory concentration of dissolved zinc salt (ZnCl(2)), indicating that zinc dissolution could not solely account for the observed toxicity. Inhibition of seed germination by ZnO depended on particle size, with nanoparticles exerting higher toxicity than larger (micron-sized) particles at equivalent concentrations. Overall, this study shows that direct exposure to nanoparticles significantly contributed to phytotoxicity and underscores the need for eco-responsible disposal of wastes and sludge containing metal oxide nanoparticles.
Collapse
Affiliation(s)
- Chang Woo Lee
- Department of Civil and Environmental Engineering, Rice University, MS-317, Houston, Texas 77005, USA
| | | | | | | | | | | | | |
Collapse
|
28
|
Abstract
In nature, plants are challenged with hurricane winds, monsoon rains, and herbivory attacks, in addition to many other harsh mechanical perturbations that can threaten plant survival. As a result, over many years of evolution, plants have developed very sensitive mechanisms through which they can perceive and respond to even subtle stimuli, like touch. Some plants respond behaviourally to the touch stimulus within seconds, while others show morphogenetic alterations over long periods of time, ranging from days to weeks. Various signalling molecules and phytohormones, including intracellular calcium, jasmonates, ethylene, abscisic acid, auxin, brassinosteroids, nitric oxide, and reactive oxygen species, have been implicated in touch responses. Many genes are induced following touch. These genes encode proteins involved in various cellular processes including calcium sensing, cell wall modifications, and defence. Twenty-three per cent of these up-regulated genes contain a recently identified promoter element involved in the rapid induction in transcript levels following mechanical perturbations. The employment of various genetic, biochemical, and molecular tools may enable elucidation of the mechanisms through which plants perceive mechano-stimuli and transduce the signals intracellularly to induce appropriate responses.
Collapse
Affiliation(s)
- E Wassim Chehab
- Rice University, Biochemistry and Cell Biology, 6100 Main St. Houston, TX 77005, USA
| | | | | |
Collapse
|
29
|
Ma W, Smigel A, Tsai YC, Braam J, Berkowitz GA. Innate immunity signaling: cytosolic Ca2+ elevation is linked to downstream nitric oxide generation through the action of calmodulin or a calmodulin-like protein. Plant Physiol 2008; 148:818-28. [PMID: 18689446 PMCID: PMC2556846 DOI: 10.1104/pp.108.125104] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2008] [Accepted: 07/28/2008] [Indexed: 05/18/2023]
Abstract
Ca(2+) rise and nitric oxide (NO) generation are essential early steps in plant innate immunity and initiate the hypersensitive response (HR) to avirulent pathogens. Previous work from this laboratory has demonstrated that a loss-of-function mutation of an Arabidopsis (Arabidopsis thaliana) plasma membrane Ca(2+)-permeable inwardly conducting ion channel impairs HR and that this phenotype could be rescued by the application of a NO donor. At present, the mechanism linking cytosolic Ca(2+) rise to NO generation during pathogen response signaling in plants is still unclear. Animal nitric oxide synthase (NOS) activation is Ca(2+)/calmodulin (CaM) dependent. Here, we present biochemical and genetic evidence consistent with a similar regulatory mechanism in plants: a pathogen-induced Ca(2+) signal leads to CaM and/or a CaM-like protein (CML) activation of NOS. In wild-type Arabidopsis plants, the use of a CaM antagonist prevents NO generation and the HR. Application of a CaM antagonist does not prevent pathogen-induced cytosolic Ca(2+) elevation, excluding the possibility of CaM acting upstream from Ca(2+). The CaM antagonist and Ca(2+) chelation abolish NO generation in wild-type Arabidopsis leaf protein extracts as well, suggesting that plant NOS activity is Ca(2+)/CaM dependent in vitro. The CaM-like protein CML24 has been previously associated with NO-related phenotypes in Arabidopsis. Here, we find that innate immune response phenotypes (HR and [avirulent] pathogen-induced NO elevation in leaves) are inhibited in loss-of-function cml24-4 mutant plants. Pathogen-associated molecular pattern-mediated NO generation in cells of cml24-4 mutants is impaired as well. Our work suggests that the initial pathogen recognition signal of Ca(2+) influx into the cytosol activates CaM and/or a CML, which then acts to induce downstream NO synthesis as intermediary steps in a pathogen perception signaling cascade, leading to innate immune responses, including the HR.
Collapse
Affiliation(s)
- Wei Ma
- Agricultural Biotechnology Laboratory, University of Connecticut, Storrs, CT 06269-4163, USA
| | | | | | | | | |
Collapse
|
30
|
Tsai YC, Delk NA, Chowdhury NI, Braam J. Arabidopsis potential calcium sensors regulate nitric oxide levels and the transition to flowering. Plant Signal Behav 2007; 2:446-54. [PMID: 19517005 PMCID: PMC2634334 DOI: 10.4161/psb.2.6.4695] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 07/05/2007] [Indexed: 05/18/2023]
Abstract
In plants, flowering is a critical developmental transition orchestrated by four regulatory pathways. Distinct alleles encoding mutant forms of the Arabidopsis potential calcium sensor CML24 cause alterations in flowering time. CML24 can act as a switch in the response to day length perception; loss-of-function cml24 mutants are late flowering under long days, whereas apparent gain of CML24 function results in early flowering. CML24 function is required for proper CONSTANS (CO) expression; components upstream of CO in the photoperiod pathway are largely unaffected in the cml24 mutants. In conjunction with CML23, a related calmodulin-like protein, CML24 also inhibits FLOWERING LOCUS C (FLC) expression and therefore impacts the autonomous regulatory pathway of the transition to flowering. Nitric oxide (NO) levels are elevated in cml23/cml24 double mutants and are largely responsible for FLC transcript accumulation. Therefore, CML23 and CML24 are potential calcium sensors that have partially overlapping function that may act to transduce calcium signals to regulate NO accumulation. In turn, NO levels influence the transition to flowering through both the photoperiod and autonomous regulatory pathways.
Collapse
Affiliation(s)
- Yu-Chang Tsai
- Biochemistry and Cell Biology; Rice University; Houston, Texas USA
| | | | | | | |
Collapse
|
31
|
Becnel J, Natarajan M, Kipp A, Braam J. Developmental expression patterns of Arabidopsis XTH genes reported by transgenes and Genevestigator. Plant Mol Biol 2006; 61:451-67. [PMID: 16830179 DOI: 10.1007/s11103-006-0021-z] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 02/06/2006] [Indexed: 05/10/2023]
Abstract
The plant cell wall is the structural basis of cellular form and thus forms a foundation on which morphogenesis builds organs and tissues. Enzymes capable of modifying major wall components are prominent candidates for regulating wall form and function. Xyloglucan endotransglucosylases/hydrolases (XTHs) are predicted to participate in xyloglucan integration and/or restructuring. XTHs are encoded by large gene families in plants; the Arabidopsis genome encodes 33 XTHs. To gain insight into the potential physiological relevance of the distinct members of this family, GUS reporter fusion genes were constructed, and plants expressing these transgenes were characterized to reveal spatial and temporal patterns of expression. In addition, Genevestigator sources were mined for comprehensive and comparative XTH expression regulation analysis. These data reveal that the Arabidopsis XTHs are likely expressed in every developmental stage from seed germination through flowering. All organs show XTH::GUS expression and most, if not all, are found to express multiple XTH::GUS genes. These data suggest that XTHs may contribute to morphogenesis at every developmental stage and in every plant organ. Different XTHs have remarkably diverse and distinct expression patterns indicating that paralogous genes have evolved differential expression regulation perhaps contributing to the maintenance of the large gene family. Extensive overlap in XTH expression patterns is evident; thus, XTHs may act combinatorially in determining wall properties of specific tissues or organs. Knowledge of gene-specific expression among family members yields evidence of where and when gene products may function and provides insights to guide rational approaches to investigate function through reverse genetics.
Collapse
Affiliation(s)
- Jaime Becnel
- Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | | | | | | |
Collapse
|
32
|
Delk NA, Johnson KA, Chowdhury NI, Braam J. CML24, regulated in expression by diverse stimuli, encodes a potential Ca2+ sensor that functions in responses to abscisic acid, daylength, and ion stress. Plant Physiol 2005; 139:240-53. [PMID: 16113225 PMCID: PMC1203374 DOI: 10.1104/pp.105.062612] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Revised: 05/10/2005] [Accepted: 05/15/2005] [Indexed: 05/04/2023]
Abstract
Changes in intracellular calcium (Ca(2+)) levels serve to signal responses to diverse stimuli. Ca(2+) signals are likely perceived through proteins that bind Ca(2+), undergo conformation changes following Ca(2+) binding, and interact with target proteins. The 50-member calmodulin-like (CML) Arabidopsis (Arabidopsis thaliana) family encodes proteins containing the predicted Ca(2+)-binding EF-hand motif. The functions of virtually all these proteins are unknown. CML24, also known as TCH2, shares over 40% amino acid sequence identity with calmodulin, has four EF hands, and undergoes Ca(2+)-dependent changes in hydrophobic interaction chromatography and migration rate through denaturing gel electrophoresis, indicating that CML24 binds Ca(2+) and, as a consequence, undergoes conformational changes. CML24 expression occurs in all major organs, and transcript levels are increased from 2- to 15-fold in plants subjected to touch, darkness, heat, cold, hydrogen peroxide, abscisic acid (ABA), and indole-3-acetic acid. However, CML24 protein accumulation changes were not detectable. The putative CML24 regulatory region confers reporter expression at sites of predicted mechanical stress; in regions undergoing growth; in vascular tissues and various floral organs; and in stomata, trichomes, and hydathodes. CML24-underexpressing transgenics are resistant to ABA inhibition of germination and seedling growth, are defective in long-day induction of flowering, and have enhanced tolerance to CoCl(2), molybdic acid, ZnSO(4), and MgCl(2). MgCl(2) tolerance is not due to reduced uptake or to elevated Ca(2+) accumulation. Together, these data present evidence that CML24, a gene expressed in diverse organs and responsive to diverse stimuli, encodes a potential Ca(2+) sensor that may function to enable responses to ABA, daylength, and presence of various salts.
Collapse
Affiliation(s)
- Nikkí A Delk
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892, USA
| | | | | | | |
Collapse
|
33
|
McCormack E, Tsai YC, Braam J. Handling calcium signaling: Arabidopsis CaMs and CMLs. Trends Plant Sci 2005; 10:383-9. [PMID: 16023399 DOI: 10.1016/j.tplants.2005.07.001] [Citation(s) in RCA: 301] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2005] [Revised: 05/24/2005] [Accepted: 07/01/2005] [Indexed: 05/03/2023]
Abstract
The Arabidopsis genome harbors seven calmodulin (CAM) and 50 CAM-like (CML) genes that encode potential calcium sensors. The CAMs encode only four protein isoforms. Selective pressure to maintain multiple CAMs indicates nonredundancy. Sequence divergence, even in the EF hand calcium-binding motif, exists among the CMLs and, therefore, divergent functions are likely to have evolved. Expression data recently available from Massively Parallel Signature Sequencing and Genevestigator compilation of microarrays are reviewed. The seven Arabidopsis CAMs are highly and relatively uniformly expressed. Differential expression is evident among the distinct CMLs over developmental stages, in various organs and in response to many different stimuli. In spite of the potential importance in mediating plant calcium signaling, the physiological functions of the Arabidopsis CaMs and CMLs remain largely unknown.
Collapse
|
34
|
Abstract
The Arabidopsis genome harbors seven calmodulin (CAM) and 50 CAM-like (CML) genes that encode potential calcium sensors. The CAMs encode only four protein isoforms. Selective pressure to maintain multiple CAMs indicates nonredundancy. Sequence divergence, even in the EF hand calcium-binding motif, exists among the CMLs and, therefore, divergent functions are likely to have evolved. Expression data recently available from Massively Parallel Signature Sequencing and Genevestigator compilation of microarrays are reviewed. The seven Arabidopsis CAMs are highly and relatively uniformly expressed. Differential expression is evident among the distinct CMLs over developmental stages, in various organs and in response to many different stimuli. In spite of the potential importance in mediating plant calcium signaling, the physiological functions of the Arabidopsis CaMs and CMLs remain largely unknown.
Collapse
|
35
|
Lee D, Polisensky DH, Braam J. Genome-wide identification of touch- and darkness-regulated Arabidopsis genes: a focus on calmodulin-like and XTH genes. New Phytol 2005; 165:429-44. [PMID: 15720654 DOI: 10.1111/j.1469-8137.2004.01238.x] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We sought to gain insight into functions potentially altered by mechanostimulation and investigate the relationship between touch and darkness responses. Microarrays and quantitative RT-PCR were conducted to identify genes and analyze behaviors of calmodulin-like (CML) and xyloglucan endotransglucosylase/hydrolase (XTH) genes. Strikingly, 589 genes had touch-inducible expression; 171 had reduced expression. Darkness increased expression of 461 genes and decreased expression of 72 genes. Over half of the touch-inducible genes resembled the TCH genes in that they were also up-regulated by darkness; 67% of those darkness-inducible were also touch inducible. Expression of 12 CMLs and four XTHs was elevated by touch; three XTHs had reduced expression. In darkness-treated plants, 10 CMLs and nine XTHs had increased expression and one XTH was repressed. Over 2.5% of total genes were touch-inducible. Many were also darkness up-regulated, consistent with the hypothesis that these stimuli have partially overlapping signal transduction pathways. Regulated gene identities suggest that calcium and kinase signaling, wall modification, disease resistance and downstream transcriptional responses may be altered in response to mechanostimulation or darkness.
Collapse
Affiliation(s)
- Dennis Lee
- Biochemistry and Cell Biology, Rice University, 6100 Main St, Houston, TX 77005-1892, USA
| | | | | |
Collapse
|
36
|
Abstract
Perception and response to mechanical stimuli are likely essential at the cellular and organismal levels. Elaborate and impressive touch responses of plants capture the imagination as such behaviors are unexpected in otherwise often quiescent creatures. Touch responses can turn plants into aggressors against animals, trapping and devouring them, and enable flowers to be active in ensuring crosspollination and shoots to climb to sunlit heights. Morphogenesis is also influenced by mechanical perturbations, including both dynamic environmental stimuli, such as wind, and constant forces, such as gravity. Even individual cells must sense turgor and wall integrity, and subcellular organelles can translocate in response to mechanical perturbations. Signaling molecules and hormones, including intracellular calcium, reactive oxygen species, octadecanoids and ethylene, have been implicated in touch responses. Remarkably, touch-induced gene expression is widespread; more than 2.5% of Arabidopsis genes are rapidly up-regulated in touch-stimulated plants. Many of these genes encode calcium-binding, cell wall modifying, defense, transcription factor and kinase proteins. With these genes as tools, molecular genetic methods may enable elucidation of mechanisms of touch perception, signal transduction and response regulation.
Collapse
Affiliation(s)
- Janet Braam
- Biochemistry and Cell Biology, Rice University, 6100 Main St, Houston, TX 77005-1892, USA.
| |
Collapse
|
37
|
Affiliation(s)
- Elizabeth McCormack
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005–1892, USA
| | - Janet Braam
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005–1892, USA
| |
Collapse
|
38
|
Rose JKC, Braam J, Fry SC, Nishitani K. The XTH family of enzymes involved in xyloglucan endotransglucosylation and endohydrolysis: current perspectives and a new unifying nomenclature. Plant Cell Physiol 2002; 43:1421-35. [PMID: 12514239 DOI: 10.1093/pcp/pcf171] [Citation(s) in RCA: 463] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The polysaccharide xyloglucan is thought to play an important structural role in the primary cell wall of dicotyledons. Accordingly, there is considerable interest in understanding the biochemical basis and regulation of xyloglucan metabolism, and research over the last 16 years has identified a large family of cell wall proteins that specifically catalyze xyloglucan endohydrolysis and/or endotransglucosylation. However, a confusing and contradictory series of nomenclatures has emerged in the literature, of which xyloglucan endotransglycosylases (XETs) and endoxyloglucan transferases (EXGTs) are just two examples, to describe members of essentially the same class of genes/proteins. The completion of the first plant genome sequencing projects has revealed the full extent of this gene family and so this is an opportune time to resolve the many discrepancies in the database that include different names being assigned to the same gene. Following consultation with members of the scientific community involved in plant cell wall research, we propose a new unifying nomenclature that conveys an accurate description of the spectrum of biochemical activities that cumulative research has shown are catalyzed by these enzymes. Thus, a member of this class of genes/proteins will be referred to as a xyloglucan endotransglucosylase/hydrolase (XTH). The two known activities of XTH proteins are referred to enzymologically as xyloglucan endotransglucosylase (XET, which is hereby re-defined) activity and xyloglucan endohydrolase (XEH) activity. This review provides a summary of the biochemical and functional diversity of XTHs, including an overview of the structure and organization of the Arabidopsis XTH gene family, and highlights the potentially important roles that XTHs appear to play in numerous examples of plant growth and development.
Collapse
Affiliation(s)
- Jocelyn K C Rose
- Department of Plant Biology, 228 Plant Science Building, Cornell University, Ithaca, NY 14853, USA.
| | | | | | | |
Collapse
|
39
|
Iliev EA, Xu W, Polisensky DH, Oh MH, Torisky RS, Clouse SD, Braam J. Transcriptional and posttranscriptional regulation of Arabidopsis TCH4 expression by diverse stimuli. Roles of cis regions and brassinosteroids. Plant Physiol 2002; 130:770-83. [PMID: 12376643 PMCID: PMC166605 DOI: 10.1104/pp.008680] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2002] [Revised: 06/09/2002] [Accepted: 06/19/2002] [Indexed: 05/18/2023]
Abstract
The Arabidopsis TCH4 gene is up-regulated in expression by diverse environmental and hormonal stimuli. Because TCH4 encodes a xyloglucan endotransglucosylase/hydrolase, this change in expression may reflect a recruitment of cell wall-modifying activity in response to environmental stress and growth. How diverse stimuli lead to the common response of TCH4 expression regulation is not known. Here, we show that induction of expression by the diverse stimuli of touch, darkness, cold, heat, and brassinosteroids (BRs) is conferred to reporter genes by the same 102-bp 5'-untranscribed TCH4 region; this result is consistent with the idea that shared regulatory elements are employed by diverse stimuli. Distal regions influence magnitude and kinetics of expression and likely harbor regulatory elements that are redundant with those located more proximal to the transcriptional start site. Substitution of the proximal regulatory region sequences in the context of distal elements does not disrupt inducible expression. TCH4 expression induction is transcriptional, at least in part because 5'-untranscribed sequences are sufficient to confer this regulation. However, 5'-untranslated sequences are necessary and sufficient to confer the marked transience of TCH4 expression, most likely through an effect on mRNA stability. Perception of BR is not necessary for TCH4::GUS induction by environmental stimuli because regulation is intact in the BR-insensitive mutant, bri1-2. The full response to auxin, however, requires the functioning of BRI1. Developmental expression of TCH4 is unlikely to be meditated by BR because TCH4::GUS is expressed in BR perception and biosynthetic mutants bri1-2 and det2-1, respectively.
Collapse
Affiliation(s)
- Emanuil A Iliev
- Biochemistry and Cell Biology, Rice University, Houston, TX 77251-1892, USA
| | | | | | | | | | | | | |
Collapse
|
40
|
Steele NM, Sulová Z, Campbell P, Braam J, Farkas V, Fry SC. Ten isoenzymes of xyloglucan endotransglycosylase from plant cell walls select and cleave the donor substrate stochastically. Biochem J 2001; 355:671-9. [PMID: 11311129 PMCID: PMC1221782 DOI: 10.1042/bj3550671] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To map the preferred cleavage sites of xyloglucan endotransglycosylases (XETs; EC 2.4.1.207) along the donor substrate chain, we incubated the enzymes with tamarind (Tamarindus indica) xyloglucan (donor substrate; approximately 205 kDa; 21 microM) plus the nonasaccharide [(3)H]XLLGol (Gal(2).Xyl(3).Glc(3). [(3)H]glucitol; acceptor substrate; 0.6 microM). After short incubation times, to minimize multiple cleavages, the size of the (3)H-labelled transglycosylation products (determined by gel-permeation chromatography) indicated the positions of the cleavage sites relative to the non-reducing terminus of the donor. There was very little difference between the size profiles of the products formed by any of ten XETs tested [one native XET purified from cauliflower (Brassica oleracea) florets, four native XET isoenzymes purified from etiolated mung-bean (Phaseolus aureus) shoots, native XETs purified from lentil (Lens culinaris) and nasturtium (Tropaeolum majus) seeds, and three insect-cell-produced thale-cress (Arabidopsis thaliana) XETs (EXGT, TCH4 and MERI-5)]. All such product profiles showed a good fit to a model in which the enzyme chooses its donor substrate independently of size and attacks it, once only, at a randomly selected cleavage site. The results therefore do not support the hypothesis that different XET isoenzymes are adapted to produce longer or shorter products such as might favour either the efficient integration of new xyloglucan into the cell wall or the re-structuring of old xyloglucan within an expanding wall.
Collapse
Affiliation(s)
- N M Steele
- The Edinburgh Cell Wall Group, Institute of Cell and Molecular Biology, The University of Edinburgh, Daniel Rutherford Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JH, Scotland, UK
| | | | | | | | | | | |
Collapse
|
41
|
Abstract
The plant cell wall is very complex, both in structure and function. The wall components and the mechanical properties of the wall have been implicated in conveying information that is important for morphogenesis. Proteoglycans, fragments of polysaccharides and the structural integrity of the wall may relay signals that influence cellular differentiation and growth control. Furthering our knowledge of cell wall structure and function is likely to have a profound impact on our understanding of how plant cells communicate with the extracellular environment.
Collapse
Affiliation(s)
- J Braam
- Biochemistry and Cell Biology, Rice University, Houston, TX 77251-1892, USA.
| |
Collapse
|
42
|
Abstract
Plant cells are enclosed by walls that define the shapes and sizes of cells and mediate cell-to-cell contact. The dynamics of plant growth, morphogenesis and differentiation require concomitant modifications of the walls. A class of enzymes known as xyloglucan endotransglycosylases have the potential to enzymatically modify wall components, but although their biochemical activity has been defined, the physiological roles of xyloglucan endotransglycosylases remain undefined. Xyloglucan endotransglycosylases are encoded by large gene families, and in an attempt to clarify their physiological role, the diverse regulation of the genes and properties of the proteins are being determined.
Collapse
Affiliation(s)
- P Campbell
- Dept of Botany, Duke University, Durham, NC 27708-1000, USA.
| | | |
Collapse
|
43
|
Abstract
Xyloglucan endotransglycosylases (XETs) are encoded by a gene family in Arabidopsis thaliana. These enzymes modify a major structural component of the plant cell wall, xyloglucan, and therefore may influence plant growth and development. We have produced four Arabidopsis XETs (TCH4, Meri-5, EXGT and XTR9) using the baculovirus/insect cell system and compared their biochemical activities. TCH4, as previously demonstrated, and the other three proteins are capable of carrying out transglycosylation of xyloglucans. The K(m) for XLLGol acceptor oligosaccharide is in the range of 20-40 microM for all the XETs except XTR9, which has a Km of 5 microM and is significantly inhibited by high levels of XLLGol. All four enzymes are most active between pH 6.0 and 6.5. TCH4 and XTR9 have temperature optima of 18 degrees C, whereas Meri-5 and EXGT are most active at 28 and 37 degrees C, respectively. Although the activity levels of three of the XETs are not influenced by the presence of fucose on the xyloglucan polymer, XTR9 has a clear preference for non-fucosylated xyloglucan polymer. The four XETs show a marked preference for XLLGol over either XXFGol or XXXGol as acceptor oligosaccharide. All four XETs are glycosylated; however, only the activities of TCH4 and Meri-5 are affected by the removal of the N-glycan with PNGase F. These four enzymes most likely function solely as transglycosylases because xyloglucan endoglucanase activity was not apparent. Subtle differences in biochemical activities may influence the physiological functions of the distinct XETs in vivo.
Collapse
Affiliation(s)
- P Campbell
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | | |
Collapse
|
44
|
Abstract
TCH4 encodes a xyloglucan endotransglycosylase (XET) of Arabidopsis thaliana. XETs endolytically cleave and religate xyloglucan polymers; xyloglucan is one of the primary structural components of the plant cell wall. Therefore, XET function may affect cell shape and plant morphogenesis. To gain insight into the biochemical function of TCH4, we defined structural requirements for optimal XET activity. Recombinant baculoviruses were designed to produce distinct forms of TCH4. TCH4 protein engineered to be synthesized in the cytosol and thus lack normal co- and post-translational modifications is virtually inactive. TCH4 proteins, with and without a polyhistidine tag, that harbor an intact N-terminus are directed to the secretory pathway. Thus, as predicted, the N-terminal region of TCH4 functions as a signal peptide. TCH4 is shown to have at least one disulfide bond as monitored by a mobility shift in SDS-PAGE in the presence of dithiothreitol (DTT). This disulfide bond(s) is essential for full XET activity. TCH4 is glycosylated in vivo; glycosidases that remove N-linked glycosylation eliminated 98% of the XET activity. Thus, co- and/or post-translational modifications are critical for optimal TCH4 XET activity. Furthermore, using site-specific mutagenesis, we demonstrated that the first glutamate residue of the conserved DEIDFEFL motif (E97) is essential for activity. A change to glutamine at this position resulted in an inactive protein; a change to aspartic acid caused protein mislocalization. These data support the hypothesis that, in analogy to Bacillus beta-glucanases, this region may be the active site of XET enzymes.
Collapse
Affiliation(s)
- P Campbell
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA
| | | |
Collapse
|
45
|
Johnson KA, Sistrunk ML, Polisensky DH, Braam J. Arabidopsis thaliana responses to mechanical stimulation do not require ETR1 or EIN2. Plant Physiol 1998; 116:643-9. [PMID: 9489014 PMCID: PMC35122 DOI: 10.1104/pp.116.2.643] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/1997] [Accepted: 10/23/1997] [Indexed: 05/18/2023]
Abstract
Plants exposed to repetitive touch or wind are generally shorter and stockier than sheltered plants. These mechanostimulus-induced developmental changes are termed thigmomorphogenesis and may confer resistance to subsequent stresses. An early response of Arabidopsis thaliana to touch or wind is the up-regulation of TCH (touch) gene expression. The signal transduction pathway that leads to mechanostimulus responses is not well defined. A role for ethylene has been proposed based on the observation that mechanostimulation of plants leads to ethylene evolution and exogenous ethylene leads to thigmomorphogenetic-like changes. To determine whether ethylene has a role in plant responses to mechanostimulation, we assessed the ability of two ethylene-insensitive mutants, etr1-3 and ein2-1, to undergo thigmomorphogenesis and TCH gene up-regulation of expression. The ethylene-insensitive mutants responded to wind similarly to the wild type, with a delay in flowering, decrease in inflorescence elongation rate, shorter mature primary inflorescences, more rosette paraclades, and appropriate TCH gene expression changes. Also, wild-type and mutant Arabidopsis responded to vibrational stimulation, with an increase in hypocotyl elongation and up-regulation of TCH gene expression. We conclude that the ETR1 and EIN2 protein functions are not required for the developmental and molecular responses to mechanical stimulation.
Collapse
Affiliation(s)
- K A Johnson
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892, USA
| | | | | | | |
Collapse
|
46
|
Antosiewicz DM, Purugganan MM, Polisensky DH, Braam J. Cellular localization of Arabidopsis xyloglucan endotransglycosylase-related proteins during development and after wind stimulation. Plant Physiol 1997; 115:1319-28. [PMID: 9414546 PMCID: PMC158597 DOI: 10.1104/pp.115.4.1319] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
A gene family encoding xyloglucan endotransglycosylase (XET)-related proteins exists in Arabidopsis. TCH4, a member of this family, is strongly up-regulated by environmental stimuli and encodes an XET capable of modifying cell wall xyloglucans. To investigate XET localization we generated antibodies against the TCH4 carboxyl terminus. The antibodies recognized TCH4 and possibly other XET-related proteins. These data indicate that XETs accumulate in expanding cell, at the sites of intercellular airspace formation, and at the bases of leaves, cotyledons, and hypocotyls. XETs also accumulated in vascular tissue, where cell wall modifications lead to the formation of tracheary elements and sieve tubes. Thus, XETs may function in modifying cell walls to allow growth, airspace formation, the development of vasculature, and reinforcement of regions under mechanical strain. Following wind stimulation, overall XET levels appeared to decrease in the leaves of wind-stimulated plants. However, consistent with an increase in TCH4 mRNA levels following wind, there were regions that showed increased immunoreaction, including sites around cells of the pith parenchyma, between the vascular elements, and within the epidermis. These results indicate that TCH4 may contribute to the adaptive changes in morphogenesis that occur in Arabidopsis following exposure to mechanical stimuli.
Collapse
Affiliation(s)
- D M Antosiewicz
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892, USA
| | | | | | | |
Collapse
|
47
|
Purugganan MM, Braam J, Fry SC. The Arabidopsis TCH4 xyloglucan endotransglycosylase. Substrate specificity, pH optimum, and cold tolerance. Plant Physiol 1997; 115:181-90. [PMID: 9306698 PMCID: PMC158473 DOI: 10.1104/pp.115.1.181] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Xyloglucan endotransglycosylases (XETs) modify a major component of the plant cell wall and therefore may play critical roles in generating tissue properties and influencing morphogenesis. An XET-related gene family exists in Arabidopsis thaliana, the members of which show differential regulation of expression. TCH4 expression is rapidly regulated by mechanical stimuli, temperature shifts, light, and hormones. As a first step in determining whether Arabidopsis XET-related proteins have distinct properties, we produced recombinant TCH4 protein in bacteria and determined its enzymatic characteristics. TCH4 specifically transglycosylates only xyloglucan. The enzyme prefers to transfer a portion of a donor polymer onto another xyloglucan polymer (acceptor); TCH4 will also utilize xyloglucan-derived oligosaccharides as acceptors but discriminates between differentially fucosylated oligosaccharides. TCH4 is most active at pH 6.0 to 6.5 and is surprisingly cold-tolerant with an optimum of 12 to 18 degrees C. TCH4 activity is enhanced by urea and bovine serum albumin, but nor cations, reducing agents, or carboxymethylcellulose. These studies indicate that TCH4 is specific for xyloglucan, but that the molecular mass and the fucosyl content of the substrates influence enzymatic reaction rates. TCH4 is unlikely to play a role in acid-induced wall loosening but may function in cold acclimation or cold-tolerant growth.
Collapse
Affiliation(s)
- M M Purugganan
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892, USA
| | | | | |
Collapse
|
48
|
Abstract
Plants adapt to various stresses by developmental alterations that render them less easily damaged. Expression of the TCH2 gene of Arabidopsis is strongly induced by stimuli such as touch and wind. The gene product, TCH2, belongs to the calmodulin (CaM) family of proteins and contains four highly conserved Ca(2+)-binding EF-hands. We describe here the structure of TCH2 in the fully Ca(2+)-saturated form, constructed using comparative molecular modeling, based on the x-ray structure of paramecium CaM. Like known CaMs, the overall structure consists of two globular domains separated by a linker helix. However, the linker region has added flexibility due to the presence of 5 glycines within a span of 6 residues. In addition, TCH2 is enriched in Lys and Arg residues relative to other CaMs, suggesting a preference for targets which are more negatively charged. Finally, a pair of Cys residues in the C-terminal domain, Cys126 and Cys131, are sufficiently close in space to form a disulfide bridge. These predictions serve to direct future biochemical and structural studies with the overall aim of understanding the role of TCH2 in the cellular response of Arabidopsis to environmental stimuli.
Collapse
Affiliation(s)
- A R Khan
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | | | | | | |
Collapse
|
49
|
Braam J, Sistrunk ML, Polisensky DH, Xu W, Purugganan MM, Antosiewicz DM, Campbell P, Johnson KA. Plant responses to environmental stress: regulation and functions of the Arabidopsis TCH genes. Planta 1997; 203 Suppl:S35-S41. [PMID: 9299794 DOI: 10.1007/pl00008113] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Expression of the Arabidopsis TCH genes is markedly upregulated in response to a variety of environmental stimuli including the seemingly innocuous stimulus of touch. Understanding the mechanism(s) and factors that control TCH gene regulation will shed light on the signaling pathways that enable plants to respond to environmental conditions. The TCH proteins include calmodulin, calmodulin-related proteins and a xyloglucan endotransglycosylase. Expression analyses and localization of protein accumulation indicates that the potential sites of TCH protein function include expanding cells and tissues under mechanical strain. We hypothesize that at least a subset of the TCH proteins may collaborate in cell wall biogenesis.
Collapse
Affiliation(s)
- J Braam
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA.
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Braam J, Sistrunk ML, Polisensky DH, Xu W, Purugganan MM, Antosiewicz DM, Campbell P, Johnson KA. Life in a changing world: TCH gene regulation of expression and responses to environmental signals. Physiol Plant 1996; 98:909-916. [PMID: 11539337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The Arabidopsis TCH genes were discovered as a consequence of their marked upregulation of expression in response to seemingly innocuous stimuli such as touch. Further analyses have indicated that these genes are upregulated by a variety of diverse stimuli. Understanding the mechanism(s) and factors that control TCH gene regulation will shed light on the signaling pathways that enable plants to respond to changing environmental conditions. The TCH proteins include calmodulin, calmodulin-related proteins and a xyloglucan endotransglycosylase. Expression analyses and localization of protein accumulation indicate that the potential sites of TCH protein function include expanding cells and tissues under mechanical strain. We hypothesize that the TCH proteins may collaborate in cell wall biogenesis.
Collapse
Affiliation(s)
- J Braam
- Dept of Biochemistry and Cell Biology, Rice Univ., Houston, TX 77055-1892, USA.
| | | | | | | | | | | | | | | |
Collapse
|