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1.
Methods Mol Biol ; 2798: 101-130, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38587738

RESUMO

Abiotic and biotic stress conditions lead to production of reactive carbonyl species (RCS) which are lipid peroxide derivatives and have detrimental effects on plant cells especially at high concentrations. There are several molecules that can be classified in RCS; among them, 4-hydroxy-(E)-2-nonenal (HNE) and acrolein are widely recognized and studied because of their toxicity. The toxicity mechanisms of RCS are well known in animals but their roles in plant systems especially signaling aspects in metabolism need to be addressed. This chapter focuses on the production mechanisms of RCS in plants as well as how plants scavenge and modify them to prevent irreversible damage in the cell. We aimed to get a comprehensive look at the literature to summarize the signaling roles of RCS in plant metabolism and their interaction with other signaling mechanisms such as highly recognized reactive oxygen species (ROS) signaling. Changing climate promotes more severe abiotic stress effects on plants which also decrease yield on the field. The effects of abiotic stress conditions on RCS metabolism are also gathered in this chapter including their signaling roles during abiotic stresses. Different methods of measuring RCS in plants are also presented in this chapter to draw more attention to the study of RCS metabolism in plants.


Assuntos
Acroleína , Clima , Animais , Peróxidos Lipídicos , Células Vegetais , Espécies Reativas de Oxigênio
2.
Biomolecules ; 14(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38540732

RESUMO

A growing number of studies have indicated that extracellular vesicles (EVs), such as exosomes, are involved in the development of neurodegenerative diseases. Components of EVs with biological effects like proteins, nucleic acids, or other molecules can be delivered to recipient cells to mediate physio-/pathological processes. For instance, some aggregate-prone proteins, such as ß-amyloid and α-synuclein, had been found to propagate through exosomes. Therefore, either an increase of detrimental molecules or a decrease of beneficial molecules enwrapped in EVs may fully or partly indicate disease progression. Numerous studies have demonstrated that dysbiosis of the gut microbiota and neurodegeneration are tightly correlated, well-known as the "gut-brain axis". Accumulating evidence has revealed that the gut bacteria-derived EVs play a pivotal role in mediating microbe-host interactions and affect the function of the "gut-brain axis", which subsequently contributes to the pathogenesis of neurodegenerative diseases. In this review, we first briefly discuss the role of EVs from mammalian cells and microbes in mediating the progression of neurodegenerative diseases, and then propose a novel strategy that employs EVs of plants (plant cell-derived exosome-like nanoparticles) for treating neurodegeneration.


Assuntos
Exossomos , Vesículas Extracelulares , Doenças Neurodegenerativas , Animais , Doenças Neurodegenerativas/metabolismo , Células Vegetais/metabolismo , Vesículas Extracelulares/metabolismo , Exossomos/metabolismo , Bactérias , Mamíferos
3.
Nat Plants ; 10(3): 350-351, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38454062
4.
Nat Plants ; 10(3): 483-493, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38454063

RESUMO

Morphogenesis of multicellular organs requires coordination of cellular growth. In plants, cell growth is determined by turgor pressure and the mechanical properties of the cell wall, which also glues cells together. Because plants have to integrate tissue-scale mechanical stresses arising through growth in a fixed tissue topology, they need to monitor cell wall mechanical status and adapt growth accordingly. Molecular factors have been identified, but whether cell geometry contributes to wall sensing is unknown. Here we propose that plant cell edges act as cell-wall-sensing domains during growth. We describe two Receptor-Like Proteins, RLP4 and RLP4-L1, which occupy a unique polarity domain at cell edges established through a targeted secretory transport pathway. We show that RLP4s associate with the cell wall at edges via their extracellular domain, respond to changes in cell wall mechanics and contribute to directional growth control in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Parede Celular/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Plantas/metabolismo , Proliferação de Células , Células Vegetais/metabolismo
5.
Curr Opin Plant Biol ; 78: 102527, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484440

RESUMO

Cell size affects many processes, including exchange of nutrients and external signals, cell division and tissue mechanics. Across eukaryotes, cells have evolved mechanisms that assess their own size to inform processes such as cell cycle progression or gene expression. Here, we review recent progress in understanding plant cell size regulation and its implications, relating these findings to work in other eukaryotes. Highlights include use of DNA contents as reference point to control the cell cycle in shoot meristems, a size-dependent cell fate decision during stomatal development and insights into the interconnection between ploidy, cell size and cell wall mechanics.


Assuntos
Células Vegetais , Plantas , Ciclo Celular/genética , Divisão Celular , Diferenciação Celular/genética , Plantas/genética , Ploidias , Tamanho Celular , Regulação da Expressão Gênica de Plantas/genética
6.
Methods Mol Biol ; 2772: 49-75, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38411806

RESUMO

The plant endoplasmic reticulum forms a network of tubules connected by three-way junctions or sheet-like cisternae. Although the network is three-dimensional, in many plant cells, it is constrained to thin volume sandwiched between the vacuole and plasma membrane, effectively restricting it to a 2-D planar network. The structure of the network, and the morphology of the tubules and cisternae can be automatically extracted following intensity-independent edge-enhancement and various segmentation techniques to give an initial pixel-based skeleton, which is then converted to a graph representation. ER dynamics can be determined using optical flow techniques from computer vision or persistency analysis. Collectively, this approach yields a wealth of quantitative metrics for ER structure and can be used to describe the effects of pharmacological treatments or genetic manipulation. The software is publicly available.


Assuntos
Benchmarking , Retículo Endoplasmático , Membrana Celular , Alimentos , Células Vegetais
7.
Methods Mol Biol ; 2772: 179-190, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38411814

RESUMO

Optical tweezers have been used to trap and micro-manipulate several biological specimens ranging from DNA, macromolecules, organelles, to single-celled organisms. Using a combination of the refraction and scattering of laser light from a focused laser beam, refractile objects are physically captured and can be moved within the surrounding media. The technique is routinely used to determine biophysical properties such as the forces exerted by motor proteins. Here, we describe how optical tweezers combined with total internal reflection fluorescence microscopy (TIRF) can be used to assess physical interactions between organelles, more specifically the ER and Golgi bodies in plant cells.


Assuntos
Microscopia , Pinças Ópticas , Células Vegetais , Complexo de Golgi , Biofísica
8.
Methods Mol Biol ; 2772: 291-299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38411823

RESUMO

Photoconvertible fluorescent proteins (pcFPs) enable differential coloring of a single organelle. Several pcFP-based probes have been targeted to the endoplasmic reticulum (ER) and can serve as useful tools to study ER dynamics and interactions with other organelles. Here, we describe the procedure to conduct live-cell imaging experiments using ER-targeted pcFP-based probes. Potential problems that might occur during the experiments, their solutions, and several ways to improve the experiments are discussed.


Assuntos
Retículo Endoplasmático , Células Vegetais , Corantes
9.
Plant Cell Environ ; 47(3): 928-946, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38164082

RESUMO

The green leaf volatiles (GLVs) Z-3-hexen-1-ol (Z3-HOL) and Z-3-hexenyl acetate (Z3-HAC) are airborne infochemicals released from damaged plant tissues that induce defenses and developmental responses in receiver plants, but little is known about their mechanism of action. We found that Z3-HOL and Z3-HAC induce similar but distinctive physiological and signaling responses in tomato seedlings and cell cultures. In seedlings, Z3-HAC showed a stronger root growth inhibition effect than Z3-HOL. In cell cultures, the two GLVs induced distinct changes in MAP kinase (MAPK) activity and proton fluxes as well as rapid and massive changes in the phosphorylation status of proteins within 5 min. Many of these phosphoproteins are involved in reprogramming the proteome from cellular homoeostasis to stress and include pattern recognition receptors, a receptor-like cytoplasmic kinase, MAPK cascade components, calcium signaling proteins and transcriptional regulators. These are well-known components of damage-associated molecular pattern (DAMP) signaling pathways. These rapid changes in the phosphoproteome may underly the activation of defense and developmental responses to GLVs. Our data provide further evidence that GLVs function like DAMPs and indicate that GLVs coopt DAMP signaling pathways.


Assuntos
Células Vegetais , Compostos Orgânicos Voláteis , Células Vegetais/metabolismo , Plântula/metabolismo , Plantas/metabolismo , Transdução de Sinais , Folhas de Planta/metabolismo , Compostos Orgânicos Voláteis/metabolismo
10.
Methods Mol Biol ; 2771: 27-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285387

RESUMO

Double-stranded RNA (dsRNA) is the replicate intermediate of all RNA viruses, and is also recognized by their host cells as a virus-invading molecule signal. Analysis of the localization and dynamic of virus-induced dsRNA can reveal crucial information concerning the molecular mechanism of virus replication and host responses to viral infection. In this chapter, we provide an easy and efficient protocol called dsRNA binding-dependent fluorescence complementation (dRBFC) assay for labeling the dsRNAs in living plant cells using two different plant RNA viruses, namely potato virus X and turnip mosaic virus. Moreover, both YFP- and mRFP-based dRBFC plasmids are available for the flexibility of experiment design.


Assuntos
Potexvirus , RNA de Cadeia Dupla , RNA de Cadeia Dupla/genética , Células Vegetais , Bioensaio , Potexvirus/genética , RNA de Plantas
11.
Nature ; 626(7999): 484-485, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297053
12.
Plant Cell Environ ; 47(4): 1348-1362, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38223941

RESUMO

The first and committed step in proline synthesis from glutamate is catalyzed by δ1 -pyrroline-5-carboxylate synthetase (P5CS). Two P5CS genes have been found in most angiosperms, one constitutively expressed to satisfy proline demand for protein synthesis, the other stress-induced. Despite the number of papers to investigate regulation at the transcriptional level, to date, the properties of the enzymes have been subjected to limited study. The isolation of Arabidopsis thaliana P5CS isoenzymes was achieved through heterologous expression and affinity purification. The two proteins were characterized with respect to kinetic and biochemical properties. AtP5CS2 showed KM values in the micro- to millimolar range, and its activity was inhibited by NADP+ , ADP and proline, and by glutamine and arginine at high levels. Mg2+ ions were required for activity, which was further stimulated by K+ and other cations. AtP5CS1 displayed positive cooperativity with glutamate and was almost insensitive to inhibition by proline. In the presence of physiological, nonsaturating concentrations of glutamate, proline was slightly stimulatory, and glutamine strongly increased the catalytic rate. Data suggest that the activity of AtP5CS isoenzymes is differentially regulated by a complex array of factors including the concentrations of proline, glutamate, glutamine, monovalent cations and pyridine dinucleotides.


Assuntos
Arabidopsis , Pirróis , Arabidopsis/genética , Glutamina , Isoenzimas , Células Vegetais/metabolismo , Plantas/metabolismo , Prolina/metabolismo , Ácido Glutâmico , Ligases
13.
Plant Physiol Biochem ; 207: 108332, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224638

RESUMO

Proteins from the glutathione peroxidase (GPX) family, such as GPX4 or PHGPX in animals, are extensively studied for their antioxidant functions and apoptosis inhibition. GPXs can be selenium-independent or selenium-dependent, with selenium acting as a potential cofactor for GPX activity. However, the relationship of plant GPXs to these functions remains unclear. Recent research indicated an upregulation of Theobroma cacao phospholipid hydroperoxide glutathione peroxidase gene (TcPHGPX) expression during early witches' broom disease stages, suggesting the use of antioxidant mechanisms as a plant defense strategy to reduce disease progression. Witches' broom disease, caused by the hemibiotrophic fungus Moniliophthora perniciosa, induces cell death through elicitors like MpNEP2 in advanced infection stages. In this context, in silico and in vitro analyses of TcPHGPX's physicochemical and functional characteristics may elucidate its antioxidant potential and effects against cell death, enhancing understanding of plant GPXs and informing strategies to control witches' broom disease. Results indicated TcPHGPX interaction with selenium compounds, mainly sodium selenite, but without improving the protein function. Protein-protein interaction network suggested cacao GPXs association with glutathione and thioredoxin metabolism, engaging in pathways like signaling, peroxide detection for ABA pathway components, and anthocyanin transport. Tests on tobacco cells revealed that TcPHGPX reduced cell death, associated with decreased membrane damage and H2O2 production induced by MpNEP2. This study is the first functional analysis of TcPHGPX, contributing to knowledge about plant GPXs and supporting studies for witches' broom disease control.


Assuntos
Agaricales , Cacau , Selênio , Cacau/microbiologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Selênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Células Vegetais , Agaricales/metabolismo , Morte Celular , Glutationa Peroxidase/metabolismo , Doenças das Plantas/microbiologia
14.
Plant Cell Environ ; 47(2): 527-539, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37946673

RESUMO

Plant aquaporins (AQPs) facilitate the membrane diffusion of water and small solutes, including hydrogen peroxide (H2 O2 ) and, possibly, cations, essential signalling molecules in many physiological processes. While the determination of the channel activity generally depends on heterologous expression of AQPs in Xenopus oocytes or yeast cells, we established a genetic tool to determine whether they facilitate the diffusion of H2 O2 through the plasma membrane in living plant cells. We designed genetic constructs to co-express the fluorescent H2 O2 sensor HyPer and AQPs, with expression controlled by a heat shock-inducible promoter in Nicotiana tabacum BY-2 suspension cells. After induction of ZmPIP2;5 AQP expression, a HyPer signal was recorded when the cells were incubated with H2 O2 , suggesting that ZmPIP2;5 facilitates H2 O2 transmembrane diffusion; in contrast, the ZmPIP2;5W85A mutated protein was inactive as a water or H2 O2 channel. ZmPIP2;1, ZmPIP2;4 and AtPIP2;1 also facilitated H2 O2 diffusion. Incubation with abscisic acid and the elicitor flg22 peptide induced the intracellular H2 O2 accumulation in BY-2 cells expressing ZmPIP2;5. We also monitored cation channel activity of ZmPIP2;5 using a novel fluorescent photo-switchable Li+ sensor in BY-2 cells. BY-2 suspension cells engineered for inducible expression of AQPs as well as HyPer expression and the use of Li+ sensors constitute a powerful toolkit for evaluating the transport activity and the molecular determinants of PIPs in living plant cells.


Assuntos
Aquaporinas , Peróxido de Hidrogênio , Peróxido de Hidrogênio/metabolismo , Células Vegetais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Aquaporinas/genética , Aquaporinas/metabolismo , Membrana Celular/metabolismo , Cátions/metabolismo , Água/metabolismo
15.
Plant Physiol ; 194(3): 1253-1254, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-37943849
16.
New Phytol ; 241(4): 1525-1542, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38017688

RESUMO

Stomatal movement involves ion transport across the plasma membrane (PM) and vacuolar membrane (VM) of guard cells. However, the coupling mechanisms of ion transporters in both membranes and their interplay with Ca2+ and pH changes are largely unclear. Here, we investigated transporter networks in tobacco guard cells and mesophyll cells using multiparametric live-cell ion imaging and computational simulations. K+ and anion fluxes at both, PM and VM, affected H+ and Ca2+ , as changes in extracellular KCl or KNO3 concentrations were accompanied by cytosolic and vacuolar pH shifts and changes in [Ca2+ ]cyt and the membrane potential. At both membranes, the K+ transporter networks mediated an antiport of K+ and H+ . By contrast, net transport of anions was accompanied by parallel H+ transport, with differences in transport capacity for chloride and nitrate. Guard and mesophyll cells exhibited similarities in K+ /H+ transport but cell type-specific differences in [H+ ]cyt and pH-dependent [Ca2+ ]cyt signals. Computational cell biology models explained mechanistically the properties of transporter networks and the coupling of transport across the PM and VM. Our integrated approach indicates fundamental principles of coupled ion transport at membrane sandwiches to control H+ /K+ homeostasis and points to transceptor-like Ca2+ /H+ -based ion signaling in plant cells.


Assuntos
Células Vegetais , Estômatos de Plantas , Membrana Celular/metabolismo , Transporte de Íons , Homeostase , Concentração de Íons de Hidrogênio , Estômatos de Plantas/metabolismo
17.
Plant J ; 117(2): 364-384, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37864806

RESUMO

Autophagy, a fundamental cellular process, plays a vital role in maintaining cellular homeostasis by degrading damaged or unnecessary components. While selective autophagy has been extensively studied in animal cells, its significance in plant cells has only recently gained attention. In this review, we delve into the intriguing realm selective autophagy in plants, with specific focus on its involvement in nutrient recycling, organelle turnover, and stress response. Moreover, recent studies have unveiled the interesting interplay between selective autophagy and epigenetic mechanisms in plants, elucidating the significance of epigenetic regulation in modulating autophagy-related gene expression and finely tuning the selective autophagy process in plants. By synthesizing existing knowledge, this review highlights the emerging field of selective autophagy in plant cells, emphasizing its pivotal role in maintaining nutrient homeostasis, facilitating cellular adaptation, and shedding light on the epigenetic regulation that governs these processes. Our comprehensive study provides the way for a deeper understanding of the dynamic control of cellular responses to nutrient availability and stress conditions, opening new avenues for future research in this field of autophagy in plant physiology.


Assuntos
Epigênese Genética , Células Vegetais , Animais , Células Vegetais/metabolismo , Autofagia , Plantas/genética , Plantas/metabolismo , Organelas
18.
Nucleic Acids Res ; 52(D1): D1629-D1638, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37638765

RESUMO

Recent advancements in single-cell RNA sequencing (scRNA-seq) technology have enabled the comprehensive profiling of gene expression patterns at the single-cell level, offering unprecedented insights into cellular diversity and heterogeneity within plant tissues. In this study, we present a systematic approach to construct a plant single-cell database, scPlantDB, which is publicly available at https://biobigdata.nju.edu.cn/scplantdb. We integrated single-cell transcriptomic profiles from 67 high-quality datasets across 17 plant species, comprising approximately 2.5 million cells. The data underwent rigorous collection, manual curation, strict quality control and standardized processing from public databases. scPlantDB offers interactive visualization of gene expression at the single-cell level, facilitating the exploration of both single-dataset and multiple-dataset analyses. It enables systematic comparison and functional annotation of markers across diverse cell types and species while providing tools to identify and compare cell types based on these markers. In summary, scPlantDB serves as a comprehensive database for investigating cell types and markers within plant cell atlases. It is a valuable resource for the plant research community.


Assuntos
Bases de Dados Factuais , Perfilação da Expressão Gênica , Células Vegetais , Plantas/genética , Análise de Sequência de RNA , Análise de Célula Única , Transcriptoma/genética
19.
Trends Plant Sci ; 29(2): 126-129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37778886

RESUMO

Plant metabolic engineering must take into consideration the heterogeneous cell types that play a role in metabolite production; cells do not participate equally. We posit that artificial intelligence (AI) developed for biomedical purposes can be applied to plant cell characterization to accelerate the development of metabolic engineering strategies in plants.


Assuntos
Engenharia Metabólica , Células Vegetais , Células Vegetais/metabolismo , Inteligência Artificial , Plantas/genética , Plantas/metabolismo
20.
Methods Mol Biol ; 2722: 171-200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37897608

RESUMO

Inducing the differentiation of specific cell type(s) synchronously and on-demand is a great experimental system to understand the sequential progression of the cellular processes, their timing and their resulting properties for distinct isolated plant cells independently of their tissue context. The inducible differentiation in cell suspension cultures, moreover, enables to obtain large quantities of distinct cell types at specific development stage, which is not possible when using whole plants. The differentiation of tracheary elements (TEs) - the cell type responsible for the hydro-mineral sap conduction and skeletal support of plants in xylem tissues - has been the most studied using inducible cell suspension cultures. We herein describe how to establish and use inducible pluripotent suspension cell cultures (iPSCs) in Arabidopsis thaliana to trigger on-demand different cell types, such as TEs or mesophyll cells. We, moreover, describe the methods to establish, monitor, and modify the sequence, duration, and properties of differentiated cells using iPSCs.


Assuntos
Arabidopsis , Células Vegetais , Técnicas de Cultura de Células , Arabidopsis/metabolismo , Plantas , Diferenciação Celular
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