1
|
Aghdam MS, Razavi F, Jia H. TOR and SnRK1 signaling pathways manipulation for improving postharvest fruits and vegetables marketability. Food Chem 2024; 456:139987. [PMID: 38852461 DOI: 10.1016/j.foodchem.2024.139987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/26/2024] [Accepted: 06/03/2024] [Indexed: 06/11/2024]
Abstract
During postharvest life, intracellular sugar insufficiency accompanied by insufficient intracellular ATP and NADPH supply, intracellular ROS overaccumulation along with intracellular ABA accumulation arising from water shortage could be responsible for accelerating fruits and vegetables deterioration through promoting SnRK1 and SnRK2 signaling pathways while preventing TOR signaling pathway. By TOR and SnRK1 signaling pathways manipulation, sufficient intracellular ATP and NADPH providing, supporting phenols, flavonoids and anthocyanins accumulation accompanied by improving DPPH, FRAP, and ABTS scavenging capacity by enhancing phenylpropanoid pathway activity, stimulating endogenous salicylic acid accumulation and NPR1-TGA-PRs signaling pathway, enhancing fatty acids biosynthesis, elongation and unsaturation, suppressing intracellular ROS overaccumulation, and promoting endogenous sucrose accumulation could be responsible for chilling injury palliating, fungal decay alleviating, senescence delaying and sensory and nutritional quality preservation in fruits and vegetables. Therefore, TOR and SnRK1 signaling pathways manipulation during postharvest shelf life by employing eco-friendly approaches such as exogenous trehalose and ATP application or engaging biotechnological approaches such as genome editing CRISPR-Cas9 or sprayable double-stranded RNA-based RNA interference would be applicable for improving fruits and vegetables marketability.
Collapse
Affiliation(s)
| | - Farhang Razavi
- Department of Horticulture, Faculty of Agriculture, University of Zanjan, Zanjan, Iran.
| | - Haifeng Jia
- College of Agriculture, Guangxi University, No. 100, Daxue Road, Nanning, Guangxi 530004, China.
| |
Collapse
|
2
|
Li G, Zhao Y. The critical roles of three sugar-related proteins (HXK, SnRK1, TOR) in regulating plant growth and stress responses. HORTICULTURE RESEARCH 2024; 11:uhae099. [PMID: 38863993 PMCID: PMC11165164 DOI: 10.1093/hr/uhae099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/25/2024] [Indexed: 06/13/2024]
Abstract
Sugar signaling is one of the most critical regulatory signals in plants, and its metabolic network contains multiple regulatory factors. Sugar signal molecules regulate cellular activities and organism development by combining with other intrinsic regulatory factors and environmental inputs. HXK, SnRK1, and TOR are three fundamental proteins that have a pivotal role in the metabolism of sugars in plants. HXK, being the initial glucose sensor discovered in plants, is renowned for its multifaceted characteristics. Recent investigations have unveiled that HXK additionally assumes a significant role in plant hormonal signaling and abiotic stress. SnRK1 serves as a vital regulator of growth under energy-depleted circumstances, whereas TOR, a large protein, acts as a central integrator of signaling pathways that govern cell metabolism, organ development, and transcriptome reprogramming in response to diverse stimuli. Together, these two proteins work to sense upstream signals and modulate downstream signals to regulate cell growth and proliferation. In recent years, there has been an increasing amount of research on these three proteins, particularly on TOR and SnRK1. Furthermore, studies have found that these three proteins not only regulate sugar signaling but also exhibit certain signal crosstalk in regulating plant growth and development. This review provides a comprehensive overview and summary of the basic functions and regulatory networks of these three proteins. It aims to serve as a reference for further exploration of the interactions between these three proteins and their involvement in co-regulatory networks.
Collapse
Affiliation(s)
- Guangshuo Li
- College of Enology and Horticulture, Ningxia University, Yinchuan 750021, China
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, 2100 Copenhagen East, Denmark
| | - Ying Zhao
- College of Enology and Horticulture, Ningxia University, Yinchuan 750021, China
| |
Collapse
|
3
|
Díaz-Cruz GA, Bignell DRD. Exploring the specialized metabolome of the plant pathogen Streptomyces sp. 11-1-2. Sci Rep 2024; 14:10414. [PMID: 38710735 DOI: 10.1038/s41598-024-60630-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 04/25/2024] [Indexed: 05/08/2024] Open
Abstract
Streptomyces bacteria are notable for producing chemically diverse specialized metabolites that exhibit various bioactivities and mediate interactions with different organisms. Streptomyces sp. 11-1-2 is a plant pathogen that produces nigericin and geldanamycin, both of which display toxic effects against various plants. Here, the 'One Strain Many Compounds' approach was used to characterize the metabolic potential of Streptomyces sp. 11-1-2. Organic extracts were prepared from 11-1-2 cultures grown on six different agar media, and the extracts were tested in antimicrobial and plant bioassays and were subjected to untargeted metabolomics and molecular networking. Most extracts displayed strong bioactivity against Gram-positive bacteria and yeast, and they exhibited phytotoxic activity against potato tuber tissue and radish seedlings. Several known specialized metabolites, including musacin D, galbonolide B, guanidylfungin A, meridamycins and elaiophylin, were predicted to be present in the extracts along with closely related compounds with unknown structure and bioactivity. Targeted detection confirmed the presence of elaiophylin in the extracts, and bioassays using pure elaiophylin revealed that it enhances the phytotoxic effects of geldanamycin and nigericin on potato tuber tissue. Overall, this study reveals novel insights into the specialized metabolites that may mediate interactions between Streptomyces sp. 11-1-2 and other bacteria and eukaryotic organisms.
Collapse
Affiliation(s)
- Gustavo A Díaz-Cruz
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada
- Phytopathology Department, Plant Protection Research Center (CIPROC), Agronomy School, Universidad de Costa Rica, San Jose, Costa Rica
| | - Dawn R D Bignell
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada.
| |
Collapse
|
4
|
Rabeh K, Oubohssaine M, Hnini M. TOR in plants: Multidimensional regulators of plant growth and signaling pathways. JOURNAL OF PLANT PHYSIOLOGY 2024; 294:154186. [PMID: 38330538 DOI: 10.1016/j.jplph.2024.154186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/10/2024]
Abstract
Target Of Rapamycin (TOR) represents a ubiquitous kinase complex that has emerged as a central regulator of cell growth and metabolism in nearly all eukaryotic organisms. TOR is an evolutionarily conserved protein kinase, functioning as a central signaling hub that integrates diverse internal and external cues to regulate a multitude of biological processes. These processes collectively exert significant influence on plant growth, development, nutrient assimilation, photosynthesis, fruit ripening, and interactions with microorganisms. Within the plant domain, the TOR complex comprises three integral components: TOR, RAPTOR, and LST8. This comprehensive review provides insights into various facets of the TOR protein, encompassing its origin, structure, function, and the regulatory and signaling pathways operative in photosynthetic organisms. Additionally, we explore future perspectives related to this pivotal protein kinase.
Collapse
Affiliation(s)
- Karim Rabeh
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco.
| | - Malika Oubohssaine
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
| | - Mohamed Hnini
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
| |
Collapse
|
5
|
Zou P, Wang L, Liu F, Yan Z, Chen X. Effect of interfering TOR signaling pathway on the biosynthesis of terpenoids in Salvia miltiorrhiza Bge. PLANT SIGNALING & BEHAVIOR 2023; 18:2199644. [PMID: 37039834 PMCID: PMC10101657 DOI: 10.1080/15592324.2023.2199644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The TOR (Target of Rapamycin) signaling pathway, which takes TOR kinase as the core, regulates the absorption, distribution, and recycling of nutrients by integrating metabolic network and other signaling pathways, thus participating in the plant growth-defense trade-off. While terpenoids play an important role in plant growth, development, stress response, and signal transduction. The effect of the TOR signaling pathway on terpenoid biosynthesis in plants has yet to be studied in detail. In this study, the tissue culture seedlings of Salvia miltiorrhiza were treated with the TOR inhibitor AZD8055. The results show that the roots of the control group had begun to grow on the 8th day, while the seedlings treated with AZD8055 had no rooting signs. Combined with the expression changes of genes related to the TOR signaling pathway in the first 8 days, samples on the 3rd, 6th, and 8th days were selected for RNA-Seq analysis. Through RNA-Seq analysis, a total of 50,689 unigenes were obtained from the samples of these three periods, of which 4088 unigenes showed differential expression. The function enrichment and time-series analysis of differentially expressed genes (DEGs) showed that the main influence of the TOR signal pathway on plant growth-related processes was gradually transmitted with treatment time after TOR was inhibited. Pathway enrichment analysis of DEGs showed that the genes in the biosynthesis of terpenoids, such as diterpenoid and carotenoid biosynthetic pathways, could be regulated. Compared with other stages, DEGs related to terpenoid biosynthesis were mainly regulated in the S2 stage. In addition, the genes involved in terpenoid skeleton biosynthesis was also considerably enriched in the S2 stage, according to the results of gene set enrichment analysis (GSEA) of unigenes. Inhibition of the TOR signaling pathway may affect the biosynthesis of terpenoid signaling molecules, inhibit gibberellin's biosynthesis, and promote abscisic acid's biosynthesis. This study has discussed the effect of interfering with the TOR pathway on terpenoid biosynthesis in S. miltiorrhiza from the perspective of omics and provides new insight into the interaction between the terpenoid biosynthesis pathway and the growth-defense trade-off of medicinal plants.
Collapse
Affiliation(s)
- Peijin Zou
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Lin Wang
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Fang Liu
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Zhuyun Yan
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Xin Chen
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- CONTACT Xin Chen School of Pharmacy, Chengdu University of Traditional Chinese Medicine, No. 1166, Liutai Avenue, Wenjiang District, Chengdu, Sichuan611171, China
| |
Collapse
|
6
|
Xiong F, Tian J, Wei Z, Deng K, Li Y, Zhang Y. Suppression of the target of rapamycin kinase accelerates tomato fruit ripening through reprogramming the transcription profile and promoting ethylene biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2603-2619. [PMID: 36786543 DOI: 10.1093/jxb/erad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 02/11/2023] [Indexed: 06/06/2023]
Abstract
Tomato fruit ripening is a unique process of nutritional and energy metabolism. Target of rapamycin (TOR), a conserved serine/threonine protein kinase in eukaryotes, controls cell growth and metabolism by integrating nutrient, energy, and hormone signals. However, it remains unclear whether TOR participates in the modulation of tomato fruit ripening. Here, we showed that the manipulation of SlTOR by chemical or genetic methods greatly alters the process of tomato fruit maturation. Expression pattern analysis revealed that the transcripts of SlTOR declined as fruit ripening progressed. Moreover, suppression of SlTOR by TOR inhibitor AZD8055 or knock down of its transcripts by inducible RNA interference, accelerated fruit ripening, and led to overall effects on fruit maturity, including changes in colour and metabolism, fruit softening, and expression of ripening-related genes. Genome-wide transcription analysis indicated that silencing SlTOR reprogrammed the transcript profile associated with ripening, including cell wall and phytohormone pathways, elevated the expression of ethylene biosynthetic genes, and further promoted ethylene production. In contrast, the ethylene action inhibitor 1-MCP efficiently blocked fruit maturation, even following SlTOR inhibition. These results suggest that accelerated fruit ripening caused by SlTOR inhibition depends on ethylene, and that SlTOR may function as a regulator in ethylene metabolism.
Collapse
Affiliation(s)
- Fangjie Xiong
- Biotechnology Research Center, Southwest University, Chongqing 400716, China
- School of Life Sciences, Chongqing University, Chongqing 401331, China
| | - Jianwei Tian
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Zhenzhen Wei
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Kexuan Deng
- School of Life Sciences, Chongqing University, Chongqing 401331, China
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, China
| | - Yan Li
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yanjie Zhang
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| |
Collapse
|
7
|
Caló G, De Marco MA, Salerno GL, Martínez-Noël GMA. TOR signaling in the green picoalga Ostreococcus tauri. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 323:111390. [PMID: 35868347 DOI: 10.1016/j.plantsci.2022.111390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/29/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Target of rapamycin (TOR) is a master regulator that controls growth and metabolism by integrating external and internal signals. Although there was a great progress in the study of TOR in plants and in the model alga Chlamydomonas, scarce data are available in other green algae. Thus, in this work we studied TOR signaling in Ostreococcus tauri, the smallest free-living eukaryote described to date. This picoalga is particularly important because it has a key site at the base of the green lineage and is part of the marine phytoplankton, contributing to global photosynthesis. We investigated OtTOR complex in silico and experimentally, by using first- and second-generation TOR inhibitors, such as rapamycin and PP242. We analyzed the effect of TOR down-regulation on cell growth and on the accumulation of carbon reserves. The results showed that O. tauri responds to TOR inhibitors more similarly to plants than to Chlamydomonas, being PP242 a valuable tool to study this pathway. Besides, Ottor expression analysis revealed that the kinase is dynamically regulated under nutritional stress. Our data indicate that TOR signaling is conserved in O. tauri and we propose this alga as a good and simple model for studying TOR kinase and its regulation.
Collapse
Affiliation(s)
- Gonzalo Caló
- INBIOTEC, Vieytes, 3103, 7600 Mar del Plata, Argentina; FIBA, Vieytes 3103, 7600 Mar del Plata, Argentina
| | - María Agustina De Marco
- INBIOTEC, Vieytes, 3103, 7600 Mar del Plata, Argentina; FIBA, Vieytes 3103, 7600 Mar del Plata, Argentina
| | | | | |
Collapse
|
8
|
Choi I, Ahn CS, Lee DH, Baek SA, Jung JW, Kim JK, Lee HS, Pai HS. Silencing of the Target of Rapamycin Complex Genes Stimulates Tomato Fruit Ripening. Mol Cells 2022; 45:660-672. [PMID: 35993163 PMCID: PMC9448650 DOI: 10.14348/molcells.2022.2025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/19/2022] [Accepted: 04/25/2022] [Indexed: 11/27/2022] Open
Abstract
The target of rapamycin complex (TORC) plays a key role in plant cell growth and survival by regulating the gene expression and metabolism according to environmental information. TORC activates transcription, mRNA translation, and anabolic processes under favorable conditions, thereby promoting plant growth and development. Tomato fruit ripening is a complex developmental process promoted by ethylene and specific transcription factors. TORC is known to modulate leaf senescence in tomato. In this study, we investigated the function of TORC in tomato fruit ripening using virus-induced gene silencing (VIGS) of the TORC genes, TOR, lethal with SEC13 protein 8 (LST8), and regulatory-associated protein of TOR (RAPTOR). Quantitative reverse transcription-polymerase chain reaction showed that the expression levels of tomato TORC genes were the highest in the orange stage during fruit development in Micro-Tom tomato. VIGS of these TORC genes using stage 2 tomato accelerated fruit ripening with premature orange/red coloring and decreased fruit growth, when control tobacco rattle virus 2 (TRV2)-myc fruits reached the mature green stage. TORC-deficient fruits showed early accumulation of carotenoid lycopene and reduced cellulose deposition in pericarp cell walls. The early ripening fruits had higher levels of transcripts related to fruit ripening transcription factors, ethylene biosynthesis, carotenoid synthesis, and cell wall modification. Finally, the early ripening phenotype in Micro-Tom tomato was reproduced in the commercial cultivar Moneymaker tomato by VIGS of the TORC genes. Collectively, these results demonstrate that TORC plays an important role in tomato fruit ripening by modulating the transcription of various ripening-related genes.
Collapse
Affiliation(s)
- Ilyeong Choi
- Department of Systems Biology, Yonsei University, Seoul 03722, Korea
| | - Chang Sook Ahn
- Department of Systems Biology, Yonsei University, Seoul 03722, Korea
- Platform Technology Research Center, Corporate R&D, LG Chem/LG Science Park, Seoul 07796, Korea
| | - Du-Hwa Lee
- Department of Systems Biology, Yonsei University, Seoul 03722, Korea
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), 1030 Vienna, Austria
| | - Seung-A Baek
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 22012, Korea
| | - Jung Won Jung
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 22012, Korea
| | - Jae Kwang Kim
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 22012, Korea
| | - Ho-Seok Lee
- Department of Biology, Kyung Hee University, Seoul 02447, Korea
| | - Hyun-Sook Pai
- Department of Systems Biology, Yonsei University, Seoul 03722, Korea
| |
Collapse
|
9
|
Marash I, Leibman‐Markus M, Gupta R, Avni A, Bar M. TOR inhibition primes immunity and pathogen resistance in tomato in a salicylic acid-dependent manner. MOLECULAR PLANT PATHOLOGY 2022; 23:1035-1047. [PMID: 35441436 PMCID: PMC9190978 DOI: 10.1111/mpp.13207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 02/08/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
All organisms need to sense and process information about the availability of nutrients, energy status, and environmental cues to determine the best time for growth and development. The conserved target of rapamycin (TOR) protein kinase has a central role in sensing and perceiving nutritional information. TOR connects environmental information about nutrient availability to developmental and metabolic processes to maintain cellular homeostasis. Under favourable energy conditions, TOR is activated and promotes anabolic processes such as cell division, while suppressing catabolic processes. Conversely, when nutrients are limited or environmental stresses are present, TOR is inactivated, and catabolic processes are promoted. Given the central role of TOR in regulating metabolism, several previous works have examined whether TOR is wired to plant defence. To date, the mechanisms by which TOR influences plant defence are not entirely clear. Here, we addressed this question by testing the effect of inhibiting TOR on immunity and pathogen resistance in tomato. Examining which hormonal defence pathways are influenced by TOR, we show that tomato immune responses and disease resistance to several pathogens increase on TOR inhibition, and that TOR inhibition-mediated resistance probably requires a functional salicylic acid, but not jasmonic acid, pathway. Our results support the notion that TOR is a master regulator of the development-defence switch in plants.
Collapse
Affiliation(s)
- Iftah Marash
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Meirav Leibman‐Markus
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Rupali Gupta
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Adi Avni
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Maya Bar
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| |
Collapse
|
10
|
McCready K, Spencer V, Jácome-Blásquez F, Burnett J, Viveros Sánchez IM, Riches Z, Kim M. TARGET OF RAPAMYCIN is essential for asexual vegetative reproduction in Kalanchoë. PLANT PHYSIOLOGY 2022; 189:248-263. [PMID: 34935983 PMCID: PMC9070829 DOI: 10.1093/plphys/kiab589] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/19/2021] [Indexed: 06/14/2023]
Abstract
The unique mechanism by which leaf margin cells regain potency and then form a plantlet in Kalanchoë spp. remains elusive but involves organogenesis and embryogenesis in response to age, day length, nutrient availability, and drought stress. In light of this, we investigated whether TARGET OF RAPAMYCIN (TOR), a conserved protein kinase in eukaryotes that controls cell growth and metabolism in response to nutrient and energy availability, may regulate plantlet formation. Kalanchoë daigremontiana TOR (KdTOR) was expressed in the leaf margin at the site of plantlet initiation, in the early plantlet cotyledons, and in the root tip of the developed plantlet. Both chemical and genetic inhibition of TOR Kinase activity in Kalanchoë daigremontiana leaves disrupted plantlet formation. Furthermore, downregulation of KdTOR in transgenic plants led to wide-ranging transcriptional changes, including decreased K. daigremontiana SHOOTMERISTEMLESS and K. daigremontiana LEAFYCOTYLEDON1 expression, whereas auxin treatments induced KdTOR expression in the plantlet roots. These results suggest that the KdTOR pathway controls plantlet development in cooperation with auxin, organogenesis, and embryogenesis pathways. The ancient and highly conserved TOR Kinase therefore controls diverse and unique developmental pathways, such as asexual reproduction within the land plant lineage.
Collapse
Affiliation(s)
| | | | - Francisco Jácome-Blásquez
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
| | - Jamie Burnett
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
| | | | - Zara Riches
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
| | | |
Collapse
|
11
|
Chang H, Lee C, Chang C, Jan F. FKBP-type peptidyl-prolyl cis-trans isomerase interacts with the movement protein of tomato leaf curl New Delhi virus and impacts viral replication in Nicotiana benthamiana. MOLECULAR PLANT PATHOLOGY 2022; 23:561-575. [PMID: 34984809 PMCID: PMC8916215 DOI: 10.1111/mpp.13181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 11/29/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
Begomoviruses belonging to the family Geminiviridae are plant-infecting DNA viruses. Begomoviral movement protein (MP) has been reported to be required for virus movement, host range determination, and symptom development. In the present study, the FK506-binding protein (FKBP)-type peptidyl-prolyl cis-trans isomerase (NbFKPPIase) of Nicotiana benthamiana was identified by a yeast two-hybrid screening system using the MP of tomato leaf curl New Delhi virus (ToLCNDV) oriental melon (OM) isolate (MPOM ) as bait. Transient silencing of the gene encoding NbFKPPIase increased replication of three test begomoviruses, and transient overexpression decreased viral replication, indicating that NbFKPPIase plays a role in defence against begomoviruses. However, infection of N. benthamiana by ToLCNDV-OM or overexpression of the gene encoding MPOM drastically reduced the expression of the gene encoding NbFKPPIase. Fluorescence resonance energy transfer analysis revealed that MPOM interacted with NbFKPPIase in the periphery of cells. Expression of the gene encoding NbFKPPIase was induced by salicylic acid but not by methyl jasmonate or ethylene. Moreover, the expression of the gene encoding NbFKPPIase was down-regulated in response to 6-benzylaminopurine and up-regulated in response to gibberellin or indole-3-acetic acid, suggesting a role of NbFKPPIase in plant development. Transcriptome analysis and comparison of N. benthamiana transient silencing and overexpression of the gene encoding MPOM led to the identification of several differentially expressed genes whose functions are probably associated with cell cycle regulation. Our results indicate that begomoviruses could suppress NbFKPPIase-mediated defence and biological functions by transcriptional inhibition and physical interaction between MP and NbFKPPIase to facilitate infection.
Collapse
Affiliation(s)
- Ho‐Hsiung Chang
- Department of Plant PathologyNational Chung Hsing UniversityTaichungTaiwan
| | - Chia‐Hwa Lee
- Department of Plant PathologyNational Chung Hsing UniversityTaichungTaiwan
- Ph.D. Program in Microbial GenomicsNational Chung Hsing University and Academia SinicaTaichung and TaipeiTaiwan
| | - Chung‐Jan Chang
- Department of Plant PathologyNational Chung Hsing UniversityTaichungTaiwan
- Department of Plant PathologyUniversity of GeorgiaGriffinGeorgiaUSA
| | - Fuh‐Jyh Jan
- Department of Plant PathologyNational Chung Hsing UniversityTaichungTaiwan
- Ph.D. Program in Microbial GenomicsNational Chung Hsing University and Academia SinicaTaichung and TaipeiTaiwan
- Advanced Plant Biotechnology CenterNational Chung Hsing UniversityTaichungTaiwan
| |
Collapse
|
12
|
Li B, Zhang X, Ren Q, Gao L, Tian J. NVP-BEZ235 Inhibits Renal Cell Carcinoma by Targeting TAK1 and PI3K/Akt/mTOR Pathways. Front Pharmacol 2022; 12:781623. [PMID: 35082669 PMCID: PMC8784527 DOI: 10.3389/fphar.2021.781623] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 12/07/2021] [Indexed: 12/24/2022] Open
Abstract
In spite of the promising in vitro and preclinical results, dual PI3K/Akt/mTOR inhibitor NVP-BEZ235, and ATP-competitive mTOR inhibitor PP242 both failed to confirm their inhibitory efficacy against renal cell carcinoma (RCC) in clinical settings. Therefore, a better understanding of the molecular mechanism is essential so as to provide possibilities for their use in combination with other agents. In present study, RCC cell lines (UMRC6, 786-0 and UOK121) were treated with NVP-BEZ235, PP242 or Rapamycin, an mTOR complex 1 (mTORC1)-specific inhibitor. They all suppressed cell proliferation and invasion, induced apoptosis and cell cycle arrest, and the effects were in the order of NVP-BEZ235 > PP242 > Rapamycin. Accordingly, the marked and sustained decrease in speckle-type POZ protein (SPOP) expression and phosphorylation of Akt and mTOR kinases was observed in RCC cells treated with NVP-BEZ235 and PP242, whereas only potent inhibition of mTOR activity was induced in Rapamycin-treated cells. In considering the overactivation of c-Jun and IκB-α in human renal tumor tissue, we next investigated the role of JNK and IKK pathways in the response of RCC cells to these compounds. First of all, transforming growth factor β activated kinase 1 (TAK1)-dependent activation of JNK/ (activator protein-1) AP-1 axis in RCC cells was proved by the repression of AP-1 activity with TAK1 or JNK inhibitor. Second, the profound inhibition of TAK1/JNK/AP-1 pathway was demonstrated in RCC cells treated with NVP-BEZ235 or PP242 but not Rapamycin, which is manifested as a reduction in activity of TAK1, c-Jun and AP-1. Meanwhile, subsequent to TAK1 inactivation, the activation of IκB-α was also reduced by NVP-BEZ235 and PP242. Likewise, in vivo, treatment with NVP-BEZ235 and PP242 suppressed the growth of xenografts generated from 786-0 and A498 cells, along with decreased expression of phospho-TAK1, phospho-c-Jun, and phospho-IκB-α. In contrast, Rapamycin elicited no significant inhibitory effects on tumor growth and phosphorylation of TAK1, c-Jun and IκB-α. We conclude that besides PI3K/Akt/mTOR signaling, NVP-BEZ235, and PP242 simultaneously target TAK1-dependent pathways in RCC cells. Notably, these effects were more marked in the presence of NVP-BEZ235 than PP242, indicating the potential application of NVP-BEZ235 in combination therapy for RCC.
Collapse
Affiliation(s)
- Bihui Li
- Guangxi Health Commission Key Laboratory of Tumor Immunology and Receptor-Targeted Drug Basic Research, Guilin Medical University, Guilin, China.,Department of Oncology, The Second Affiliated Hospital of Guilin Medical University, Guilin, China
| | - Xing Zhang
- Guangxi Health Commission Key Laboratory of Tumor Immunology and Receptor-Targeted Drug Basic Research, Guilin Medical University, Guilin, China
| | - Qianyao Ren
- Guangxi Health Commission Key Laboratory of Tumor Immunology and Receptor-Targeted Drug Basic Research, Guilin Medical University, Guilin, China
| | - Li Gao
- Department of Urinary Surgery, The First Affiliated Hospital of Guilin Medical University, Guilin, China
| | - Jing Tian
- Guangxi Health Commission Key Laboratory of Tumor Immunology and Receptor-Targeted Drug Basic Research, Guilin Medical University, Guilin, China
| |
Collapse
|
13
|
Smailov B, Alybayev S, Smekenov I, Mursalimov A, Saparbaev M, Sarbassov D, Bissenbaev A. Wheat Germination Is Dependent on Plant Target of Rapamycin Signaling. Front Cell Dev Biol 2020; 8:606685. [PMID: 33330509 PMCID: PMC7719826 DOI: 10.3389/fcell.2020.606685] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/21/2020] [Indexed: 12/21/2022] Open
Abstract
Germination is a process of seed sprouting that facilitates embryo growth. The breakdown of reserved starch in the endosperm into simple sugars is essential for seed germination and subsequent seedling growth. At the early stage of germination, gibberellic acid (GA) activates transcription factor GAMYB to promote de novo synthesis of isoforms of α-amylase in the aleurone layer and scutellar epithelium of the embryo. Here, we demonstrate that wheat germination is regulated by plant target of rapamycin (TOR) signaling. TOR is a central component of the essential-nutrient–dependent pathway controlling cell growth in all eukaryotes. It is known that rapamycin, a highly specific allosteric inhibitor of TOR, is effective in yeast and animal cells but ineffective in most of higher plants likely owing to structural differences in ubiquitous rapamycin receptor FKBP12. The action of rapamycin on wheat growth has not been studied. Our data show that rapamycin inhibits germination of wheat seeds and of their isolated embryos in a dose-dependent manner. The involvement of Triticum aestivum TOR (TaTOR) in wheat germination was consistent with the suppression of wheat embryo growth by specific inhibitors of the TOR kinase: pp242 or torin1. Rapamycin or torin1 interfered with GA function in germination because of a potent inhibitory effect on α-amylase and GAMYB gene expression. The TOR inhibitors selectively targeted the GA-dependent gene expression, whereas expression of the abscisic acid-dependent ABI5 gene was not affected by either rapamycin or torin1. To determine whether the TaTOR kinase activation takes place during wheat germination, we examined phosphorylation of a ribosomal protein, T. aestivum S6 kinase 1 (TaS6K1; a substrate of TOR). The phosphorylation of serine 467 (S467) in a hydrophobic motif on TaS6K1 was induced in a process of germination triggered by GA. Moreover, the germination-induced phosphorylation of TaS6K1 on S467 was dependent on TaTOR and was inhibited by rapamycin or torin1. Besides, a gibberellin biosynthesis inhibitor (paclobutrazol; PBZ) blocked not only α-amylase gene expression but also TaS6K1 phosphorylation in wheat embryos. Thus, a hormonal action of GA turns on the synthesis of α-amylase in wheat germination via activation of the TaTOR–S6K1 signaling pathway.
Collapse
Affiliation(s)
- Bauyrzhan Smailov
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Sanzhar Alybayev
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Izat Smekenov
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Aibek Mursalimov
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Murat Saparbaev
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Groupe «Mechanisms of DNA Repair and Carcinogenesis», Equipe Labellisée LIGUE 2016, CNRS UMR 9019, Université Paris-Sud, Gustave Roussy Cancer Campus, Villejuif, France
| | - Dos Sarbassov
- Department of Biology, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Amangeldy Bissenbaev
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| |
Collapse
|
14
|
Zhao Y, Wang XQ. The hot issue: TOR signalling network in plants. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 48:1-7. [PMID: 32905758 DOI: 10.1071/fp20071] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
The target of rapamycin (TOR) signalling network plays a pivotal role in regulating sugar metabolism and life-span in yeast, plants and mammals, in which TOR functions as a crucial protein. In plants, the TOR complex comprises TOR, RAPTOR (regulatory-associated protein of TOR) and LST8 (lethal with SEC13 protein 8). Factors like light, auxin, glucose, sucrose and amino acid can activate TOR protein as upstream signals to further phosphorylate downstream factors of TOR which promote cell proliferation and growth in plants. In this review, we analyse the TOR signalling network in plants and discuss the relationship between glucose and TOR, as well as the dynamic balance between TOR and sucrose-non-fermenting-related protein kinases (SnRKs). Given that 63 novel TOR-regulated proteins have been identified in previous studies, we also believe there are many unknown functions of TOR that need to be further investigated.
Collapse
Affiliation(s)
- Ying Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Xiu-Qin Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China; and Corresponding author.
| |
Collapse
|
15
|
Sun X, Chen H, Wang P, Chen F, Yuan L, Mi G. Low nitrogen induces root elongation via auxin-induced acid growth and auxin-regulated target of rapamycin (TOR) pathway in maize. JOURNAL OF PLANT PHYSIOLOGY 2020; 254:153281. [PMID: 32971423 DOI: 10.1016/j.jplph.2020.153281] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/04/2020] [Accepted: 09/04/2020] [Indexed: 05/23/2023]
Abstract
Under low nitrogen (N) supply, an important adaption of the maize root system is to promote the root elongation so as to increase N uptake from a larger soil space. The underlying physiological mechanism is largely unknown. In the present study, two maize inbred lines (Ye478 and Wu312) were used to study the possible involvement of the auxin and target of rapamycin (TOR) pathway in low-N-induced root elongation. Compared to Wu312, primary root elongation of Ye478 was more sensitive to low nitrate supply. Correspondingly, more auxin was accumulated in the root tip, and more protons were secreted, increasing the acidity of the apoplast space. On the other hand, low-N-induced root elongation was greatly reduced when shoot-to-root auxin transport was inhibited by applying N-1-naphthylphthalamic acid (NPA) at the plant base or by pruning the top leaf where auxin is mostly synthesized. Furthermore, exogenous application of TOR inhibitor also eliminated the response of root elongation under low N. The content of TOR kinase and the expression of TOR pathway-related genes were significantly changed when shoot-to-root auxin transport was reduced by NPA treatment. Taken together, it is concluded that low-N stress increases shoot-to-root auxin transport which enhances root elongation via auxin-dependent acid growth and the auxin-regulated TOR pathway in maize.
Collapse
Affiliation(s)
- Xichao Sun
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China; Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China.
| | - Huan Chen
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.
| | - Peng Wang
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.
| | - Fanjun Chen
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.
| | - Lixing Yuan
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.
| | - Guohua Mi
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.
| |
Collapse
|
16
|
Deng K, Wang W, Feng L, Yin H, Xiong F, Ren M. Target of rapamycin regulates potassium uptake in Arabidopsis and potato. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 155:357-366. [PMID: 32798904 DOI: 10.1016/j.plaphy.2020.07.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 07/24/2020] [Accepted: 07/24/2020] [Indexed: 06/11/2023]
Abstract
Potassium (K) is an essential inorganic nutrient needed by plants for their growth and development. The conserved target of rapamycin (TOR) kinase, a well-known nutrition signaling integrator, has crucial roles in regulating growth and development in all eukaryotes. Emerging evidence suggests that TOR is a core regulator of nutrient absorption and utilization in plants. However, it is still unclear whether there is a causative link between the TOR pathway and potassium absorption. Here, we show that the expression of some potassium transporters and channels was regulated by TOR, and the suppression of TOR activity significantly affected potassium uptake in Arabidopsis and potato. Furthermore, we discovered that a Type 2A phosphatase-associated protein of 46 kDa (TAP46), a direct TOR downstream effector, could interact with CBL-interacting protein kinase 23 (CIPK23) in Arabidopsis and potato. In Arabidopsis, the K+ channel AKT1 conducting K+ uptake was significantly regulated by Calcineurin B-like Calcium Sensor Protein 1/9 (CBL1/9)-CIPK23 modules. We found that the cbl1cbl9, cipk23 (lks1-2 and lks1-3), and akt1 mutants were more hyposensitive to the TOR inhibitor than the wild-type, and the TOR inhibitor induced the downregulation of K+ uptake rate in the wild-type more than in these mutants. In addition, the overexpression of CIPK23 could effectively restore the defects in growth and potassium uptake induced by the TOR inhibitors. Thus, our work reveals a link between TOR signaling and CIPK23 and provides new insight into the regulation of potassium uptake in plants.
Collapse
Affiliation(s)
- Kexuan Deng
- School of Life Sciences, Chongqing University, Chongqing, 401331, China
| | - Wanjing Wang
- School of Life Sciences, Chongqing University, Chongqing, 401331, China
| | - Li Feng
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610213, China; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 45000, China
| | - Huan Yin
- School of Life Sciences, Chongqing University, Chongqing, 401331, China
| | - Fangjie Xiong
- School of Life Sciences, Chongqing University, Chongqing, 401331, China
| | - Maozhi Ren
- School of Life Sciences, Chongqing University, Chongqing, 401331, China; Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610213, China; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 45000, China.
| |
Collapse
|
17
|
Kumar A, Daware A, Kumar A, Kumar V, Gopala Krishnan S, Mondal S, Patra BC, Singh AK, Tyagi AK, Parida SK, Thakur JK. Genome-wide analysis of polymorphisms identified domestication-associated long low-diversity region carrying important rice grain size/weight quantitative trait loci. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1525-1547. [PMID: 32432802 DOI: 10.1111/tpj.14845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 05/01/2020] [Accepted: 05/12/2020] [Indexed: 05/02/2023]
Abstract
Rice grain size and weight are major determinants of grain quality and yield and so have been under rigorous selection since domestication. However, the genetic basis for contrasting grain size/weight trait among Indian germplasms and their association with domestication-driven evolution is not well understood. In this study, two long (LGG) and two short grain (SGG) genotypes were resequenced. LGG (LGR and PB 1121) differentiated from SGG (Sonasal and Bindli) by 504 439 single nucleotide polymorphisms (SNPs) and 78 166 insertion-and-deletion polymorphisms. The LRK gene cluster was different and a truncation mutation in the LRK8 kinase domain was associated with LGG. Phylogeny with 3000 diverse rice accessions revealed that the four sequenced genotypes belonged to the japonica group and were at the edge of the clades indicating them to be the potential source of genetic diversity available in Indian rice germplasm. Six SNPs were significantly associated with grain size/weight and the top four of these could be validated in mapping a population, suggesting this study as a valuable resource for high-throughput genotyping. A contiguous long low-diversity region (LDR) of approximately 6 Mb carrying a major grain weight quantitative trait loci (harbouring OsTOR gene) was identified on Chromosome 5. This LDR was identified as an evolutionary important site with significant positive selection and multiple selection sweeps, and showed association with many domestication-related traits, including grain size/weight. The aus population retained more allelic variations in the LDR than the japonica and indica populations, suggesting it to be one of the divergence loci. All the data and analyses can be accessed from the RiceSzWtBase database.
Collapse
Affiliation(s)
- Angad Kumar
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Anurag Daware
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Arvind Kumar
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Vinay Kumar
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - S Gopala Krishnan
- Division of Genetics, ICAR-Indian Agricultural Research Institute, Pusa, New Delhi, 110012, India
| | - Subhasish Mondal
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Bhaskar C Patra
- Crop Improvement Division, ICAR-National Rice Research Institute, Cuttack, 753006, India
| | - Ashok K Singh
- Division of Genetics, ICAR-Indian Agricultural Research Institute, Pusa, New Delhi, 110012, India
| | - Akhilesh K Tyagi
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India
| | - Swarup K Parida
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Jitendra K Thakur
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| |
Collapse
|
18
|
Zhuo F, Xiong F, Deng K, Li Z, Ren M. Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in Arabidopsis. Int J Mol Sci 2020; 21:E2680. [PMID: 32290539 PMCID: PMC7215648 DOI: 10.3390/ijms21082680] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/07/2020] [Accepted: 04/10/2020] [Indexed: 12/12/2022] Open
Abstract
Target of rapamycin (TOR) acts as a master regulator in coordination of cell growth with energy and nutrient availability. Despite the increased appreciation of the essential role of the TOR complex in interaction with phytohormone signaling, little is known about its function on ethylene signaling. Here, through expression analysis, genetic and biochemical approaches, we reveal that TOR functions in the regulation of ethylene signals. Transcriptional analysis indicates that TOR inhibition by AZD8055 upregulated senescence- and ethylene-related genes expression. Furthermore, ethylene insensitive mutants like etr1-1, ein2-5 and ein3 eil1, showed more hyposensitivity to AZD8055 than that of WT in hypocotyl growth inhibition. Similarly, blocking ethylene signals by ethylene action inhibitor Ag+ or biosynthesis inhibitor aminoethoxyvinylglycine (AVG) largely rescued hypocotyl growth even in presence of AZD8055. In addition, we also demonstrated that Type 2A phosphatase-associated protein of 46 kDa (TAP46), a downstream component of TOR signaling, physically interacts with 1-aminocy-clopropane-1-carboxylate (ACC) synthase ACS2 and ACS6. Arabidopsis overexpressing ACS2 or ACS6 showed more hypersensitivity to AZD8055 than WT in hypocotyl growth inhibition. Moreover, ACS2/ACS6 protein was accumulated under TOR suppression, implying TOR modulates ACC synthase protein levels. Taken together, our results indicate that TOR participates in negatively modulating ethylene signals and the molecular mechanism is likely involved in the regulation of ethylene biosynthesis by affecting ACSs in transcription and protein levels.
Collapse
Affiliation(s)
- Fengping Zhuo
- School of Life Sciences, Chongqing University, Chongqing 401331, China; (F.Z.); (F.X.); (K.D.)
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Fangjie Xiong
- School of Life Sciences, Chongqing University, Chongqing 401331, China; (F.Z.); (F.X.); (K.D.)
| | - Kexuan Deng
- School of Life Sciences, Chongqing University, Chongqing 401331, China; (F.Z.); (F.X.); (K.D.)
| | - Zhengguo Li
- School of Life Sciences, Chongqing University, Chongqing 401331, China; (F.Z.); (F.X.); (K.D.)
| | - Maozhi Ren
- School of Life Sciences, Chongqing University, Chongqing 401331, China; (F.Z.); (F.X.); (K.D.)
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou 455001, China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610000, China
| |
Collapse
|
19
|
Pancha I, Chokshi K, Tanaka K, Imamura S. Microalgal Target of Rapamycin (TOR): A Central Regulatory Hub for Growth, Stress Response and Biomass Production. PLANT & CELL PHYSIOLOGY 2020; 61:675-684. [PMID: 32105317 DOI: 10.1093/pcp/pcaa023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/17/2020] [Indexed: 06/10/2023]
Abstract
Target of rapamycin (TOR) is an evolutionarily conserved protein kinase that plays an important role in the regulation of cell growth and the sensing of nutrient and energy status in eukaryotes. In yeasts and mammals, the roles of TOR have been very well described and various functions of TOR signaling in plant lineages have also been revealed over the past 20 years. In the case of microalgae, the functions of TOR have been primarily studied in the model green alga Chlamydomonas reinhardtii and were summarized in an earlier single review article. However, the recent development of tools for the functional analysis of TOR has helped to reveal the involvement of TOR in various functions, including autophagy, transcription, translation, accumulation of energy storage molecules, etc., in microalgae. In the present review, we discuss recent novel findings relating to TOR signaling and its roles in microalgae along with relevant information on land plants and also provide details of topics that must be addressed in future studies to reveal how TOR regulates various physiological functions in microalgae.
Collapse
Affiliation(s)
- Imran Pancha
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1 Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan
- Department of Biology, SRM University-AP, Amaravati, Andhra Pradesh 522502, India
| | - Kaumeel Chokshi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1 Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan
| | - Kan Tanaka
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1 Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan
| | - Sousuke Imamura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1 Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan
| |
Collapse
|
20
|
Xiong F, Liu M, Zhuo F, Yin H, Deng K, Feng S, Liu Y, Luo X, Feng L, Zhang S, Li Z, Ren M. Host-induced gene silencing of BcTOR in Botrytis cinerea enhances plant resistance to grey mould. MOLECULAR PLANT PATHOLOGY 2019; 20:1722-1739. [PMID: 31622007 PMCID: PMC6859489 DOI: 10.1111/mpp.12873] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Botrytis cinerea is the causal agent of grey mould for more than 200 plant species, including economically important vegetables, fruits and crops, which leads to economic losses worldwide. Target of rapamycin (TOR) acts a master regulator to control cell growth and proliferation by integrating nutrient, energy and growth factors in eukaryotic species, but little is known about whether TOR can function as a practicable target in the control of plant fungal pathogens. Here, we characterize TOR signalling of B. cinerea in the regulation of growth and pathogenicity as well as its potential value in genetic engineering for crop protection by bioinformatics analysis, pharmacological assays, biochemistry and genetics approaches. The results show that conserved TOR signalling occurs, and a functional FK506-binding protein 12 kD (FKBP12) mediates the interaction between rapamycin and B. cinerea TOR (BcTOR). RNA sequencing (RNA-Seq) analysis revealed that BcTOR displayed conserved functions, particularly in controlling growth and metabolism. Furthermore, pathogenicity assay showed that BcTOR inhibition efficiently reduces the infection of B. cinerea in plant leaves of Arabidopsis and potato or tomato fruits. Additionally, transgenic plants expressing double-stranded RNA of BcTOR through the host-induced gene silencing method could produce abundant small RNAs targeting BcTOR, and significantly block the occurrence of grey mould in potato and tomato. Taken together, our results suggest that BcTOR is an efficient target for genetic engineering in control of grey mould, and also a potential and promising target applied in the biocontrol of plant fungal pathogens.
Collapse
Affiliation(s)
- Fangjie Xiong
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Mei Liu
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Fengping Zhuo
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
- School of Chemistry and Chemical EngineeringChongqing University of Science and TechnologyChongqing401331China
| | - Huan Yin
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Kexuan Deng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Shun Feng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Yudong Liu
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Xiumei Luo
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Li Feng
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Shumin Zhang
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Zhengguo Li
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
| | - Maozhi Ren
- School of Life SciencesChongqing UniversityChongqing401331China
- Key Laboratory of Plant Hormone and Developmental Regulation of ChongqingChongqing401331China
- Institute of Urban AgricultureChinese Academy of Agricultural Sciences/National Chengdu Agricultural Science and Technology CenterChengdu610000China
| |
Collapse
|
21
|
Corona-Sánchez I, Peña-Uribe CA, González-López O, Villegas J, Campos-Garcia J, Reyes de la Cruz H. Cyclodipeptides from Pseudomonas aeruginosa modulate the maize ( Zea mays L.) root system and promote S6 ribosomal protein kinase activation. PeerJ 2019; 7:e7494. [PMID: 31523498 PMCID: PMC6717507 DOI: 10.7717/peerj.7494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/16/2019] [Indexed: 12/15/2022] Open
Abstract
Background Pseudomonas aeruginosa is an opportunistic and pathogenic bacterium with the ability to produce cyclodipeptides (CDPs), which belong to a large family of molecules with important biological activities. Excessive amounts of CDPs produced by Pseudomonas strains can activate an auxin response in Arabidopsis thaliana and promote plant growth. Target of rapamycin (TOR) is an evolutionarily conserved eukaryotic protein kinase that coordinates cell growth and metabolic processes in response to environmental and nutritional signals. Target of rapamycin kinase phosphorylates various substrates, of which S6 ribosomal protein kinase (S6K) is particularly well known. The PI3K/Akt/mTOR/S6K signaling pathway has been studied extensively in mammals because of its association with fundamental biological processes including cell differentiation. However, evidences suggest that this pathway also has specific and conserved functions in plants and may thus be conserved, as are several of its components like TOR complex 1 and S6K proteins. In plants, TOR-S6K signaling has been shown to be modulated in response to plant growth promoters or stressors. Methods In this study, we evaluated the effects of P. aeruginosa CDPs on the growth and root development of maize plants (Zea mays L.) by adding different CDPs concentrations on culture plant media, as well as the effect on the phosphorylation of the maize S6K protein (ZmS6K) by protein electrophoresis and western blot. Results Our results showed that P. aeruginosa CDPs promoted maize growth and development, including modifications in the root system architecture, correlating with the increased ZmS6K phosphorylation and changes induced in electrophoretic mobility, suggesting post-translational modifications on ZmS6K. These findings suggest that the plant growth-promoting effect of the Pseudomonas genus, associated with the CDPs production, involves the TOR/S6K signaling pathway as a mechanism of plant growth and root development in plant–microorganism interaction.
Collapse
Affiliation(s)
- Iván Corona-Sánchez
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Molecular de Plantas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Cesar Arturo Peña-Uribe
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Molecular de Plantas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Omar González-López
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Molecular de Plantas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México.,Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Microbiana, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Javier Villegas
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Agroecología, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Jesus Campos-Garcia
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Microbiana, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| | - Homero Reyes de la Cruz
- Instituto de Investigaciones Químico Biológicas, Laboratorio de Biotecnología Molecular de Plantas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México
| |
Collapse
|
22
|
Montané MH, Menand B. TOR inhibitors: from mammalian outcomes to pharmacogenetics in plants and algae. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2297-2312. [PMID: 30773593 DOI: 10.1093/jxb/erz053] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/05/2019] [Indexed: 05/19/2023]
Abstract
Target of rapamycin (TOR) is a conserved eukaryotic phosphatidylinositol 3-kinase-related kinase that regulates growth and metabolism in response to environment in plants and algae. The study of the plant and algal TOR pathway has largely depended on TOR inhibitors first developed for non-photosynthetic eukaryotes. In animals and yeast, fundamental work on the TOR pathway has benefited from the allosteric TOR inhibitor rapamycin and more recently from ATP-competitive TOR inhibitors (asTORis) that circumvent the limitations of rapamycin. The asTORis, developed for medical application, inhibit TOR complex 1 (TORC1) more efficiently than rapamycin and also inhibit rapamycin-resistant TORCs. This review presents knowledge on TOR inhibitors from the mammalian field and underlines important considerations for plant and algal biologists. It discusses the use of rapamycin and asTORis in plants and algae and concludes with guidelines for physiological studies and genetic screens with TOR inhibitors.
Collapse
Affiliation(s)
- Marie-Hélène Montané
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
| | - Benoît Menand
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
| |
Collapse
|
23
|
Song Y, Li L, Yang Z, Zhao G, Zhang X, Wang L, Zheng L, Zhuo F, Yin H, Ge X, Zhang C, Yang Z, Ren M, Li F. Target of Rapamycin (TOR) Regulates the Expression of lncRNAs in Response to Abiotic Stresses in Cotton. Front Genet 2019; 9:690. [PMID: 30671083 PMCID: PMC6332313 DOI: 10.3389/fgene.2018.00690] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/11/2018] [Indexed: 12/11/2022] Open
Abstract
TOR (Target of Rapamycin) kinase is an evolutionarily conserved protein kinase, which integrates stress-related cues with growth and metabolic outputs. Long non-coding RNAs (lncRNAs) play a vital role in the regulation of eukaryotic genes. However, little is known about TOR's function in regulating the expression of lncRNAs in plants. In this study, four putative homologous genes encoding the TOR protein were identified by utilizing the recently completed cotton genome. Pharmacological experiments with TOR inhibitor AZD8055 and on silencing GhTOR genes resulted in obvious cotton growth retardation, indicating the conserved role of TOR in plant growth. The expression pattern analyses in different tissues reveal that TOR may play a role in root development, and the transcript levels of TOR genes were changed under different stress conditions. Importantly, we found TOR may be a key player in regulating the expression of long non-coding RNAs (lncRNAs). A total of 10,315 lncRNAs were discovered in cotton seedlings, 90.7% of which were long intergenic ncRNAs. Moreover, we identified the differentially expressed lncRNAs, of which 296 were significantly upregulated and 105 were downregulated in TOR inactivated plants. GO and KEGG analyses of differentially expressed lncRNA neighboring genes reveal that these differentially expressed lncRNA-targeted genes are involved in many life processes, including stress response, glutathione, and ribosomes in cotton. A series of differentially expressed lncRNAs potentially involved in plant stress response was identified under TOR inhibition. Collectively, these results suggest that cotton TOR proteins may directly modulate the expression of putative stress-related lncRNAs and eventually play a potential role in the cotton stress response.
Collapse
Affiliation(s)
- Yun Song
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Linxuan Li
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Zhaoen Yang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Ge Zhao
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xueyan Zhang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Lingling Wang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Lei Zheng
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Fengping Zhuo
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Huan Yin
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Xiaoyang Ge
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Chaojun Zhang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Zuoren Yang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Maozhi Ren
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Fuguang Li
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.,Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| |
Collapse
|
24
|
Takeuchi T, Benning C. Nitrogen-dependent coordination of cell cycle, quiescence and TAG accumulation in Chlamydomonas. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:292. [PMID: 31890020 PMCID: PMC6927116 DOI: 10.1186/s13068-019-1635-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/12/2019] [Indexed: 05/07/2023]
Abstract
Microalgae hold great promises as sustainable cellular factories for the production of alternative fuels, feeds, and biopharmaceuticals for human health. While the biorefinery approach for fuels along with the coproduction of high-value compounds with industrial, therapeutic, or nutraceutical applications have the potential to make algal biofuels more economically viable, a number of challenges continue to hamper algal production systems at all levels. One such hurdle includes the metabolic trade-off often observed between the increased yields of desired products, such as triacylglycerols (TAG), and the growth of an organism. Initial genetic engineering strategies to improve lipid productivity in microalgae, which focused on overproducing the enzymes involved in fatty acid and TAG biosynthesis or inactivating competing carbon (C) metabolism, have seen some successes albeit at the cost of often greatly reduced biomass. Emergent approaches that aim at modifying the dynamics of entire metabolic pathways by engineering of pertinent transcription factors or signaling networks appear to have successfully achieved a balance between growth and neutral lipid accumulation. However, the biological knowledge of key signaling networks and molecular components linking these two processes is still incomplete in photosynthetic eukaryotes, making it difficult to optimize metabolic engineering strategies for microalgae. Here, we focus on nitrogen (N) starvation of the model green microalga, Chlamydomonas reinhardtii, to present the current understanding of the nutrient-dependent switch between proliferation and quiescence, and the drastic reprogramming of metabolism that results in the storage of C compounds following N starvation. We discuss the potential components mediating the transcriptional repression of cell cycle genes and the establishment of quiescence in Chlamydomonas, and highlight the importance of signaling pathways such as those governed by the target of rapamycin (TOR) and sucrose nonfermenting-related (SnRK) kinases in the coordination of metabolic status with cellular growth. A better understanding of how the cell division cycle is regulated in response to nutrient scarcity and of the signaling pathways linking cellular growth to energy and lipid homeostasis, is essential to improve the prospects of biofuels and biomass production in microalgae.
Collapse
Affiliation(s)
- Tomomi Takeuchi
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824 USA
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
| | - Christoph Benning
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824 USA
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| |
Collapse
|
25
|
Waseem M, Ahmad F, Habib S, Gao Y, Li Z. Genome-wide identification of FK506-binding domain protein gene family, its characterization, and expression analysis in tomato (Solanum lycopersicum L.). Gene 2018; 678:143-154. [DOI: 10.1016/j.gene.2018.08.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 07/16/2018] [Accepted: 08/04/2018] [Indexed: 11/26/2022]
|
26
|
Liu FF, Zhao S, Liu P, Huo SP. Influence of mTOR signaling pathway on ketamine-induced injuries in the hippocampal neurons of rats. Neurol Res 2018; 41:77-86. [PMID: 30373500 DOI: 10.1080/01616412.2018.1531203] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To explore the influences of mammalian target of rapamycin (mTOR) signaling pathway on ketamine-induced apoptosis, oxidative stress and Ca2+ concentration in the hippocampal neurons of rats. METHODS The primary hippocampal neurons isolated from fetal Sprague Dawley rats were treated with ketamine (0, 50, 100 and 500 μM) for 4 days to observe its effect on mTOR signaling pathway and apoptosis of rat hippocampal neurons. Then, the hippocampal neurons were divided into C (Control), R (Rapamycin, an inhibitor of mTOR signaling pathway), K (Ketamine) and R + K (Rapamycin + Ketamine) groups to detect the apoptosis, reactive oxygen species (ROS) production, and Ca2+ concentration via the terminal transferase uridyl nick end labelling (TUNEL) assay, dichloro-dihydro-fluorescein diacetate (DCFH-DA) method and Fluo-3 acetoxymethyl ester (Fluo-3AM) staining, respectively. The expressions of mTOR signaling pathway and apoptosis-related proteins in hippocampal neurons were examined by qRT-PCR and Western blot. RESULTS Ketamine could dose-dependently promote the apoptosis of rat hippocampal neurons with upregulation of p-mTOR and its downstream regulators (p-4E-BP-1 and p-p70S6K). However, ketamine-induced apoptosis in hippocampal neurons was reversed significantly by the administration of rapamycin, as evident by the decrease in expressions of pro-apoptotic proteins (Bax and cleaved Caspase-3) and the increase in anti-apoptotic protein (Bcl-2). Meanwhile, the ROS generation and Ca2+ concentration was inhibited accompanied with reduced malonildialdehyde levels but elevated superoxide and glutathione peroxidase activities. CONCLUSION Inhibition of mTOR signaling pathway protected rat hippocampal neurons from ketamine-induced injuries via reducing apoptosis, oxidative stress, as well as Ca2+ concentration. ABBREVIATIONS mTOR: mammalian target of rapamycin; SD: Sprague-Dawley; SPF: Specific-pathogen free; ROS: reactive oxygen species; TUNEL: terminal transferase uridyl nick end labelling; DCFH-DA: Dichloro-dihydro-fluorescein diacetate; Fluo-3A: Fluo-3 acetoxymethyl ester; NMDAR: non-competitive N-methyl-D-aspartame glutamate receptor; 4E-BP1: 4E binding protein 1; p70S6K: p70 S6 Kinase; PCR: Polymerase chain reaction; MDA: malonildialdehyde; GSH-PX: glutathione peroxidase; ANOVA: One-way Analysis of Variance.
Collapse
Affiliation(s)
- Fei-Fei Liu
- a Department of Anesthesiology , Third Hospital of Hebei Medical University , Shijiazhuang , China
| | - Shuang Zhao
- a Department of Anesthesiology , Third Hospital of Hebei Medical University , Shijiazhuang , China
| | - Peng Liu
- a Department of Anesthesiology , Third Hospital of Hebei Medical University , Shijiazhuang , China
| | - Shu-Ping Huo
- a Department of Anesthesiology , Third Hospital of Hebei Medical University , Shijiazhuang , China
| |
Collapse
|
27
|
De Vleesschauwer D, Filipe O, Hoffman G, Seifi HS, Haeck A, Canlas P, Van Bockhaven J, De Waele E, Demeestere K, Ronald P, Hofte M. Target of rapamycin signaling orchestrates growth-defense trade-offs in plants. THE NEW PHYTOLOGIST 2018; 217:305-319. [PMID: 28905991 PMCID: PMC5711548 DOI: 10.1111/nph.14785] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 08/09/2017] [Indexed: 05/18/2023]
Abstract
Plant defense to microbial pathogens is often accompanied by significant growth inhibition. How plants merge immune system function with normal growth and development is still poorly understood. Here, we investigated the role of target of rapamycin (TOR), an evolutionary conserved serine/threonine kinase, in the plant defense response. We used rice as a model system and applied a combination of chemical, genetic, genomic and cell-based analyses. We demonstrate that ectopic expression of TOR and Raptor (regulatory-associated protein of mTOR), a protein previously demonstrated to interact with TOR in Arabidopsis, positively regulates growth and development in rice. Transcriptome analysis of rice cells treated with the TOR-specific inhibitor rapamycin revealed that TOR not only dictates transcriptional reprogramming of extensive gene sets involved in central and secondary metabolism, cell cycle and transcription, but also suppresses many defense-related genes. TOR overexpression lines displayed increased susceptibility to both bacterial and fungal pathogens, whereas plants with reduced TOR signaling displayed enhanced resistance. Finally, we found that TOR antagonizes the action of the classic defense hormones salicylic acid and jasmonic acid. Together, these results indicate that TOR acts as a molecular switch for the activation of cell proliferation and plant growth at the expense of cellular immunity.
Collapse
Affiliation(s)
- David De Vleesschauwer
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Osvaldo Filipe
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Gena Hoffman
- Department of Plant Pathology and the Genome Center, University of California, Davis, CA, 95616, USA
| | - Hamed Soren Seifi
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Ashley Haeck
- Research Group EnVOC, Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Patrick Canlas
- Department of Plant Pathology and the Genome Center, University of California, Davis, CA, 95616, USA
| | - Jonas Van Bockhaven
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Evelien De Waele
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Kristof Demeestere
- Research Group EnVOC, Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Pamela Ronald
- Department of Plant Pathology and the Genome Center, University of California, Davis, CA, 95616, USA
- Joint Bioenergy Institute, Emeryville, CA, 94608, USA
| | - Monica Hofte
- Laboratory of Phytopathology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| |
Collapse
|
28
|
Imamura S, Taki K, Tanaka K. Construction of a rapamycin-susceptible strain of the unicellular red alga Cyanidioschyzon merolae for analysis of the target of rapamycin (TOR) function. J GEN APPL MICROBIOL 2017; 63:305-309. [PMID: 28954966 DOI: 10.2323/jgam.2017.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Sousuke Imamura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST)
| | - Keiko Taki
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST)
| | - Kan Tanaka
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST)
| |
Collapse
|
29
|
The TOR Signaling Network in the Model Unicellular Green Alga Chlamydomonas reinhardtii. Biomolecules 2017; 7:biom7030054. [PMID: 28704927 PMCID: PMC5618235 DOI: 10.3390/biom7030054] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 12/18/2022] Open
Abstract
Cell growth is tightly coupled to nutrient availability. The target of rapamycin (TOR) kinase transmits nutritional and environmental cues to the cellular growth machinery. TOR functions in two distinct multiprotein complexes, termed TOR complex 1 (TORC1) and TOR complex 2 (TORC2). While the structure and functions of TORC1 are highly conserved in all eukaryotes, including algae and plants, TORC2 core proteins seem to be missing in photosynthetic organisms. TORC1 controls cell growth by promoting anabolic processes, including protein synthesis and ribosome biogenesis, and inhibiting catabolic processes such as autophagy. Recent studies identified rapamycin-sensitive TORC1 signaling regulating cell growth, autophagy, lipid metabolism, and central metabolic pathways in the model unicellular green alga Chlamydomonas reinhardtii. The central role that microalgae play in global biomass production, together with the high biotechnological potential of these organisms in biofuel production, has drawn attention to the study of proteins that regulate cell growth such as the TOR kinase. In this review we discuss the recent progress on TOR signaling in algae.
Collapse
|
30
|
Deng K, Dong P, Wang W, Feng L, Xiong F, Wang K, Zhang S, Feng S, Wang B, Zhang J, Ren M. The TOR Pathway Is Involved in Adventitious Root Formation in Arabidopsis and Potato. FRONTIERS IN PLANT SCIENCE 2017; 8:784. [PMID: 28553309 PMCID: PMC5427086 DOI: 10.3389/fpls.2017.00784] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 04/26/2017] [Indexed: 05/14/2023]
Abstract
In the agriculture industry, adventitious root formation is a core issue of plants asexual propagation. However, the underlying molecular mechanism of adventitious root formation is far beyond understanding. In present study we found that target of rapamycin (TOR) signaling plays a key role in adventitious root formation in potato and Arabidopsis. The core components of TOR complex including TOR, RAPTOR, and LST8 are highly conserved in potato, but the seedlings of potato are insensitive to rapamycin, implying FK506 Binding Protein 12 KD (FKBP12) lost the function to bridge the interaction of rapamycin and TOR in potato. To dissect TOR signaling in potato, the rapamycin hypersensitive potato plants (BP12-OE) were engineered by introducing yeast FKBP12 (ScFKBP12) into potato. We found that rapamycin can significantly attenuate the capability of adventitious root formation in BP12-OE potatoes. KU63794 (KU, an active-site TOR inhibitor) combined with rapamycin can more significantly suppress adventitious root formation of BP12-OE potato than the single treatments, such as KU63794 or rapamycin, indicating its synergistic inhibitory effects on potato adventitious root formation. Furthermore, RNA-seq data showed that many genes associated with auxin signaling pathway were altered when BP12-OE potato seedlings were treated with rapamycin + KU, suggesting that TOR may play a major role in adventitious root formation via auxin signaling. The auxin receptor mutant tir1 was sensitive to TOR inhibitors and the double and quadruple mutants including tir1afb2, tir1afb3, and tir1afb1afb2afb3 displayed more sensitive to asTORis than single mutant tir1. Consistently, overexpression of AtTIR1 in Arabidopsis and potato can partially overcome the inhibitory effect of asTORis and promote adventitious root formation under asTORis treatments. These observations suggest that TOR signaling regulates adventitious root formation by mediating auxin signaling in Arabidopsis and potato.
Collapse
Affiliation(s)
- Kexuan Deng
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Pan Dong
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Wanjing Wang
- College of Agronomy and Biotechnology, Southwest UniversityChongqing, China
| | - Li Feng
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Fangjie Xiong
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Kai Wang
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Shumin Zhang
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Shun Feng
- School of Life Sciences, Chongqing UniversityChongqing, China
| | - Bangjun Wang
- Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, Ministry of Education, College of Life Sciences, Southwest UniversityChongqing, China
| | - Jiankui Zhang
- College of Agronomy and Biotechnology, Southwest UniversityChongqing, China
| | - Maozhi Ren
- School of Life Sciences, Chongqing UniversityChongqing, China
| |
Collapse
|