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1.
Cell ; 186(7): 1328-1336.e10, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37001499

RESUMO

Stressed plants show altered phenotypes, including changes in color, smell, and shape. Yet, airborne sounds emitted by stressed plants have not been investigated before. Here we show that stressed plants emit airborne sounds that can be recorded from a distance and classified. We recorded ultrasonic sounds emitted by tomato and tobacco plants inside an acoustic chamber, and in a greenhouse, while monitoring the plant's physiological parameters. We developed machine learning models that succeeded in identifying the condition of the plants, including dehydration level and injury, based solely on the emitted sounds. These informative sounds may also be detectable by other organisms. This work opens avenues for understanding plants and their interactions with the environment and may have significant impact on agriculture.


Assuntos
Plantas , Som , Estresse Fisiológico
2.
Proc Natl Acad Sci U S A ; 121(4): e2309006120, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38190516

RESUMO

Improving water use efficiency in crops is a significant challenge as it involves balancing water transpiration and CO2 uptake through stomatal pores. This study investigates the role of SlROP9, a tomato Rho of Plants protein, in guard cells and its impact on plant transpiration. The results reveal that SlROP9 null mutants exhibit reduced stomatal conductance while photosynthetic CO2 assimilation remains largely unaffected. Notably, there is a notable decrease in whole-plant transpiration in the rop9 mutants compared to the wild type, especially during noon hours when the water pressure deficit is high. The elevated stomatal closure observed in rop9 mutants is linked to an increase in reactive oxygen species formation. This is very likely dependent on the respiratory burst oxidase homolog (RBOH) NADPH oxidase and is not influenced by abscisic acid (ABA). Consistently, activated ROP9 can interact with RBOHB in both yeast and plants. In diverse tomato accessions, drought stress represses ROP9 expression, and in Arabidopsis stomatal guard cells, ABA suppresses ROP signaling. Therefore, the phenotype of the rop9 mutants may arise from a disruption in ROP9-regulated RBOH activity. Remarkably, large-scale field experiments demonstrate that the rop9 mutants display improved water use efficiency without compromising fruit yield. These findings provide insights into the role of ROPs in guard cells and their potential as targets for enhancing water use efficiency in crops.


Assuntos
Arabidopsis , Solanum lycopersicum , Solanum lycopersicum/genética , Produtos Agrícolas , Proteínas de Plantas/genética , Ácido Abscísico , Arabidopsis/genética
3.
Plant Physiol ; 193(4): 2640-2660, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37607257

RESUMO

The high rate of productivity observed in panicoid crops is in part due to their extensive root system. Recently, green foxtail (Setaria viridis) has emerged as a genetic model system for panicoid grasses. Natural accessions of S. viridis originating from different parts of the world, with differential leaf physiological behavior, have been identified. This work focused on understanding the physiological and molecular mechanisms controlling root hydraulic conductivity and root-to-shoot gas exchange signaling in S. viridis. We identified 2 accessions, SHA and ZHA, with contrasting behavior at the leaf, root, and whole-plant levels. Our results indicated a role for root aquaporin (AQP) plasma membrane (PM) intrinsic proteins in the differential behavior of SHA and ZHA. Moreover, a different root hydraulic response to low levels of abscisic acid between SHA and ZHA was observed, which was associated with root AQPs. Using cell imaging, biochemical, and reverse genetic approaches, we identified PM intrinsic protein 1;6 (PIP1;6) as a possible PIP1 candidate that regulates radial root hydraulics and root-to-shoot signaling of gas exchange in S. viridis. In heterologous systems, PIP1;6 localized in the endoplasmic reticulum, and upon interaction with PIP2s, relocalization to the PM was observed. PIP1;6 was predominantly expressed at the root endodermis. Generation of knockout PIP1;6 plants (KO-PIP1;6) in S. viridis showed altered root hydraulic conductivity, altered gas exchange, and alteration of root transcriptional patterns. Our results indicate that PIPs are essential in regulating whole-plant water homeostasis in S. viridis. We conclude that root hydraulic conductivity and gas exchange are positively associated and are regulated by AQPs.


Assuntos
Aquaporinas , Setaria (Planta) , Setaria (Planta)/metabolismo , Água/metabolismo , Folhas de Planta/metabolismo , Membrana Celular/metabolismo , Aquaporinas/genética , Aquaporinas/metabolismo , Raízes de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Plant Cell Physiol ; 63(12): 2008-2026, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36161338

RESUMO

Changes in climate conditions can negatively affect the productivity of crop plants. They can induce chloroplast degradation (senescence), which leads to decreased source capacity, as well as decreased whole-plant carbon/nitrogen assimilation and allocation. The importance, contribution and mechanisms of action regulating source-tissue capacity under stress conditions in tomato (Solanum lycopersicum) are not well understood. We hypothesized that delaying chloroplast degradation by altering the activity of the tomato chloroplast vesiculation (CV) under stress would lead to more efficient use of carbon and nitrogen and to higher yields. Tomato CV is upregulated under stress conditions. Specific induction of CV in leaves at the fruit development stage resulted in stress-induced senescence and negatively affected fruit yield, without any positive effects on fruit quality. Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 (CRISPR/CAS9) knockout CV plants, generated using a near-isogenic tomato line with enhanced sink capacity, exhibited stress tolerance at both the vegetative and the reproductive stages, leading to enhanced fruit quantity, quality and harvest index. Detailed metabolic and transcriptomic network analysis of sink tissue revealed that the l-glutamine and l-arginine biosynthesis pathways are associated with stress-response conditions and also identified putative novel genes involved in tomato fruit quality under stress. Our results are the first to demonstrate the feasibility of delayed stress-induced senescence as a stress-tolerance trait in a fleshy fruit crop, to highlight the involvement of the CV pathway in the regulation of source strength under stress and to identify genes and metabolic pathways involved in increased tomato sink capacity under stress conditions.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Frutas/metabolismo , Cloroplastos/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo
5.
Plant J ; 106(2): 301-313, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33735498

RESUMO

The leaf vascular bundle sheath cells (BSCs) that tightly envelop the leaf veins, are a selective and dynamic barrier to xylem sap water and solutes radially entering the mesophyll cells. Under normal conditions, xylem sap pH below 6 is presumably important for driving and regulating the transmembranal solute transport. Having discovered recently a differentially high expression of a BSC proton pump, AHA2, we now test the hypothesis that it regulates the xylem sap pH and leaf radial water fluxes. We monitored the xylem sap pH in the veins of detached leaves of wild-type Arabidopsis, AHA mutants and aha2 mutants complemented with AHA2 gene solely in BSCs. We tested an AHA inhibitor (vanadate) and stimulator (fusicoccin), and different pH buffers. We monitored their impact on the xylem sap pH and the leaf hydraulic conductance (Kleaf ), and the effect of pH on the water osmotic permeability (Pf ) of isolated BSCs protoplasts. We found that AHA2 is necessary for xylem sap acidification, and in turn, for elevating Kleaf . Conversely, AHA2 knockdown, which alkalinized the xylem sap, or, buffering its pH to 7.5, reduced Kleaf , and elevating external pH to 7.5 decreased the BSCs Pf . All these showed a causative link between AHA2 activity in BSCs and leaf radial hydraulic water conductance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Folhas de Planta/fisiologia , ATPases Translocadoras de Prótons/metabolismo , Xilema/fisiologia , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Concentração de Íons de Hidrogênio , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Estômatos de Plantas/citologia , Estômatos de Plantas/enzimologia , Estômatos de Plantas/fisiologia , Transpiração Vegetal/fisiologia , Xilema/enzimologia , Xilema/metabolismo
6.
Plant Cell Environ ; 43(4): 920-933, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31953871

RESUMO

High CO2 concentrations stimulate net photosynthesis by increasing CO2 substrate availability for Rubisco, simultaneously suppressing photorespiration. Previously, we reported that silencing the chloroplast vesiculation (cv) gene in rice increased source fitness, through the maintenance of chloroplast stability and the expression of photorespiration-associated genes. Because high atmospheric CO2 conditions diminished photorespiration, we tested whether CV silencing might be a viable strategy to improve the effects of high CO2 on grain yield and N assimilation in rice. Under elevated CO2 , OsCV expression was induced, and OsCV was targeted to peroxisomes where it facilitated the removal of OsPEX11-1 from the peroxisome and delivered it to the vacuole for degradation. This process correlated well with the reduction in the number of peroxisomes, the decreased catalase activity and the increased H2 O2 content in wild-type plants under elevated CO2 . At elevated CO2 , CV-silenced rice plants maintained peroxisome proliferation and photorespiration and displayed higher N assimilation than wild-type plants. This was supported by higher activity of enzymes involved in NO3- and NH4+ assimilation and higher total and seed protein contents. Co-immunoprecipitation of OsCV-interacting proteins suggested that, similar to its role in chloroplast protein turnover, OsCV acted as a scaffold, binding peroxisomal proteins.


Assuntos
Cloroplastos/metabolismo , Oryza/metabolismo , Fotossíntese , Dióxido de Carbono , Cloroplastos/genética , Cloroplastos/fisiologia , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Inativação Gênica , Genes de Plantas/genética , Genes de Plantas/fisiologia , Peróxido de Hidrogênio/metabolismo , Microscopia Eletrônica , Microscopia Eletrônica de Transmissão , Nitrogênio/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase
7.
Plant J ; 91(2): 325-339, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28390076

RESUMO

Sugars affect central aspects of plant physiology, including photosynthesis, stomatal behavior and the loss of water through the stomata. Yet, the potential effects of sugars on plant aquaporins (AQPs) and water conductance have not been examined. We used database and transcriptional analyses, as well as cellular and whole-plant functional techniques to examine the link between sugar-related genes and AQPs. Database analyses revealed a high level of correlation between the expression of AQPs and that of sugar-related genes, including the Arabidopsis hexokinases 1 (AtHXK1). Increased expression of AtHXK1, as well as the addition of its primary substrate, glucose (Glc), repressed the expression of 10 AQPs from the plasma membrane-intrinsic proteins (PIP) subfamily (PIP-AQPs) and induced the expression of two stress-related PIP-AQPs. The osmotic water permeability of mesophyll protoplasts of AtHXK1-expressing plants and the leaf hydraulic conductance of those plants were significantly reduced, in line with the decreased expression of PIP-AQPs. Conversely, hxk1 mutants demonstrated a higher level of hydraulic conductance, with increased water potential in their leaves. In addition, the presence of Glc reduced leaf water potential, as compared with an osmotic control, indicating that Glc reduces the movement of water from the xylem into the mesophyll. The production of sugars entails a significant loss of water and these results suggest that sugars and AtHXK1 affect the expression of AQP genes and reduce leaf water conductance, to coordinate sugar levels with the loss of water through transpiration.


Assuntos
Aquaporinas/genética , Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Hexoquinase/genética , Folhas de Planta/fisiologia , Açúcares/metabolismo , Aquaporinas/metabolismo , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Glucose/metabolismo , Glucose/farmacologia , Hexoquinase/metabolismo , Células do Mesofilo/metabolismo , Transpiração Vegetal , Plantas Geneticamente Modificadas
8.
Plant Mol Biol ; 96(3): 305-314, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29322303

RESUMO

KEY MESSAGE: We studied the salt stress tolerance of two accessions isolated from different areas of the world (Norway and Tunisia) and characterized the mechanism(s) regulating salt stress in Brachypodium sylvaticum Osl1 and Ain1. Perennial grasses are widely grown in different parts of the world as an important feedstock for renewable energy. Their perennial nature that reduces management practices and use of energy and agrochemicals give these biomass crops advantages when dealing with modern agriculture challenges such as soil erosion, increase in salinized marginal lands and the runoff of nutrients. Brachypodium sylvaticum is a perennial grass that was recently suggested as a suitable model for the study of biomass plant production and renewable energy. However, its plasticity to abiotic stress is not yet clear. We studied the salt stress tolerance of two accessions isolated from different areas of the world and characterized the mechanism(s) regulating salt stress in B. sylvaticum Osl1, originated from Oslo, Norway and Ain1, originated from Ain-Durham, Tunisia. Osl1 limited sodium transport from root to shoot, maintaining a better K/Na homeostasis and preventing toxicity damage in the shoot. This was accompanied by higher expression of HKT8 and SOS1 transporters in Osl1 as compared to Ain1. In addition, Osl1 salt tolerance was accompanied by higher abundance of the vacuolar proton pump pyrophosphatase and Na+/H+ antiporters (NHXs) leading to a better vacuolar pH homeostasis, efficient compartmentation of Na+ in the root vacuoles and salt tolerance. Although preliminary, our results further support previous results highlighting the role of Na+ transport systems in plant salt tolerance. The identification of salt tolerant and sensitive B. sylvaticum accessions can provide an experimental system for the study of the mechanisms and regulatory networks associated with stress tolerance in perennials grass.


Assuntos
Brachypodium/fisiologia , Tolerância ao Sal/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Brachypodium/classificação , Brachypodium/efeitos dos fármacos , Plantas Tolerantes a Sal/efeitos dos fármacos , Plantas Tolerantes a Sal/fisiologia , Estresse Fisiológico/efeitos dos fármacos
9.
J Exp Bot ; 69(4): 845-853, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-28992323

RESUMO

Senescence is an age-dependent process, ultimately leading to plant death, that in annual crop plants overlaps with the reproductive stage of development. Research on the molecular and biochemical mechanisms of leaf senescence has revealed a multi-layered regulatory network operating to control age-dependent processes. Abiotic stress-induced senescence challenges source-sink relationships and results in significant reduction in crop yields. Although processes associated with plant senescence are well studied, the mechanisms regulating stress-induced senescence are not well known. Here, we discuss the effects of abiotic stress on crop productivity, mechanisms associated with stress-induced senescence, and the possible use of these mechanisms for the generation of plant stress tolerance. We emphasize the involvement of source strength and stability of the photosynthetic apparatus in this process, and suggest a possible role of a perennial plant life strategy for the amelioration of stress-induced senescence.


Assuntos
Produtos Agrícolas/fisiologia , Folhas de Planta/fisiologia , Fenômenos Fisiológicos Vegetais , Estresse Fisiológico , Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento
10.
J Exp Bot ; 69(4): 867-878, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-28992306

RESUMO

Abiotic stress-induced senescence in crops is a process particularly affecting the photosynthetic apparatus, decreasing photosynthetic activity and inducing chloroplast degradation. A pathway for stress-induced chloroplast degradation that involves the CHLOROPLAST VESICULATION (CV) gene was characterized in rice (Oryza sativa) plants. OsCV expression was up-regulated with the age of the plants and when plants were exposed to water-deficit conditions. The down-regulation of OsCV expression contributed to the maintenance of the chloroplast integrity under stress. OsCV-silenced plants displayed enhanced source fitness (i.e. carbon and nitrogen assimilation) and photorespiration, leading to water-deficit stress tolerance. Co-immunoprecipitation, intracellular co-localization, and bimolecular fluorescence demonstrated the in vivo interaction between OsCV and chloroplastic glutamine synthetase (OsGS2), affecting source-sink relationships of the plants under stress. Our results would indicate that the OsCV-mediated chloroplast degradation pathway is involved in the regulation of nitrogen assimilation during stress-induced plant senescence.


Assuntos
Cloroplastos/metabolismo , Secas , Nitrogênio/metabolismo , Oryza/fisiologia , Proteínas de Plantas/genética , Água/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico
11.
Plant Physiol ; 166(3): 1609-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25266632

RESUMO

Our understanding of the cellular role of aquaporins (AQPs) in the regulation of whole-plant hydraulics, in general, and extravascular, radial hydraulic conductance in leaves (K(leaf)), in particular, is still fairly limited. We hypothesized that the AQPs of the vascular bundle sheath (BS) cells regulate K(leaf). To examine this hypothesis, AQP genes were silenced using artificial microRNAs that were expressed constitutively or specifically targeted to the BS. MicroRNA sequences were designed to target all five AQP genes from the PLASMA MEMBRANE-INTRINSIC PROTEIN1 (PIP1) subfamily. Our results show that the constitutively silenced PIP1 (35S promoter) plants had decreased PIP1 transcript and protein levels and decreased mesophyll and BS osmotic water permeability (P(f)), mesophyll conductance of CO2, photosynthesis, K(leaf), transpiration, and shoot biomass. Plants in which the PIP1 subfamily was silenced only in the BS (SCARECROW:microRNA plants) exhibited decreased mesophyll and BS Pf and decreased K(leaf) but no decreases in the rest of the parameters listed above, with the net result of increased shoot biomass. We excluded the possibility of SCARECROW promoter activity in the mesophyll. Hence, the fact that SCARECROW:microRNA mesophyll exhibited reduced P(f), but not reduced mesophyll conductance of CO2, suggests that the BS-mesophyll hydraulic continuum acts as a feed-forward control signal. The role of AQPs in the hierarchy of the hydraulic signal pathway controlling leaf water status under normal and limited-water conditions is discussed.


Assuntos
Aquaporinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Folhas de Planta/fisiologia , Aquaporinas/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Células do Mesofilo/metabolismo , Permeabilidade , Transpiração Vegetal/fisiologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas
12.
Plant Physiol ; 165(4): 1684-1697, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24989233

RESUMO

Vacuolar water movement is largely controlled by membrane channels called tonoplast-intrinsic aquaporins (TIP-AQPs). Some TIP-AQP genes, such as TIP2;2 and TIP1;1, are up-regulated upon exposure to biotic stress. Moreover, TIP1;1 transcript levels are higher in leaves of a tomato (Solanum lycopersicum) line resistant to Tomato yellow leaf curl virus (TYLCV) than in those of a susceptible line with a similar genetic background. Virus-induced silencing of TIP1;1 in the tomato resistant line and the use of an Arabidopsis (Arabidopsis thaliana) tip1;1 null mutant showed that resistance to TYLCV is severely compromised in the absence of TIP1:1. Constitutive expression of tomato TIP2;2 in transgenic TYLCV-susceptible tomato and Arabidopsis plants was correlated with increased TYLCV resistance, increased transpiration, decreased abscisic acid levels, and increased salicylic acid levels at the early stages of infection. We propose that TIP-AQPs affect the induction of leaf abscisic acid, which leads to increased levels of transpiration and gas exchange, as well as better salicylic acid signaling.

13.
Planta ; 239(2): 357-66, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24170337

RESUMO

The regulation of plant hydraulic conductance and gas conductance involves a number of different morphological, physiological and molecular mechanisms working in harmony. At the molecular level, aquaporins play a key role in the transport of water, as well as CO2, through cell membranes. Yet, their tissue-related function, which controls whole-plant gas exchange and water relations, is less understood. In this study, we examined the tissue-specific effects of the stress-induced tobacco Aquaporin1 (NtAQP1), which functions as both a water and CO2 channel, on whole-plant behavior. In tobacco and tomato plants, constitutive overexpression of NtAQP1 increased net photosynthesis (A(N)), mesophyll CO2 conductance (g(m)) and stomatal conductance (g(s)) and, under stress, increased root hydraulic conductivity (L(pr)) as well. Our results revealed that NtAQP1 that is specifically expressed in the mesophyll tissue plays an important role in increasing both A(N) and g(m). Moreover, targeting NtAQP1 expression to the cells of the vascular envelope significantly improved the plants' stress response. Surprisingly, NtAQP1 expression in the guard cells did not have a significant effect under any of the tested conditions. The tissue-specific involvement of NtAQP1 in hydraulic and gas conductance via the interaction between the vasculature and the stomata is discussed.


Assuntos
Aquaporina 1/genética , Arabidopsis/genética , Dióxido de Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Nicotiana/genética , Transpiração Vegetal/fisiologia , Arabidopsis/citologia , Arabidopsis/fisiologia , Dióxido de Carbono/análise , Clorofila/metabolismo , Genes Reporter , Células do Mesofilo/metabolismo , Especificidade de Órgãos , Fotossíntese , Epiderme Vegetal/citologia , Epiderme Vegetal/genética , Epiderme Vegetal/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Estômatos de Plantas/citologia , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Regiões Promotoras Genéticas/genética , Cloreto de Sódio/metabolismo , Água/metabolismo
14.
Plant Sci ; 341: 112021, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311249

RESUMO

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technologies have been implemented in recent years in the genome editing of eukaryotes, including plants. The original system of knocking out a single gene by causing a double-strand break (DSB), followed by non-homologous end joining (NHEJ) or Homology-directed repair (HDR) has undergone many adaptations. These adaptations include employing CRISPR/Cas9 to upregulate gene expression or to cause specific small changes to the DNA sequence of the gene-of-interest. In plants, multiplexing, i.e., inducing multiple changes by CRISPR/Cas9, is extremely relevant due to the redundancy of many plant genes, and the time- and labor-consuming generation of stable transgenic plant lines via crossing. Here we discuss relevant examples of various traits, such as yield, biofortification, gluten content, abiotic stress tolerance, and biotic stress resistance, which have been successfully manipulated using CRISPR/Cas9 in plants. While existing studies have primarily focused on proving the impact of CRISPR/Cas9 on a single trait, there is a growing interest among researchers in creating a multi-stress tolerant wheat cultivar 'super wheat', to commercially and sustainably enhance wheat yields under climate change. Due to the complexity of the technical difficulties in generating multi-target CRISPR/Cas9 lines and of the interactions between stress responses, we propose enhancing already commercial local landraces with higher yield traits along with stress tolerances specific to the respective localities, instead of generating a general 'super wheat'. We hope this will serve as the sustainable solution to commercially enhancing crop yields under both stable and challenging environmental conditions.


Assuntos
Sistemas CRISPR-Cas , Triticum , Triticum/genética , Edição de Genes , Plantas Geneticamente Modificadas/genética , Genes de Plantas
15.
Plant Commun ; 5(5): 100792, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38173227

RESUMO

Despite recent advances in crop metabolomics, the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown. Here, we performed widely targeted metabolite profiling of kernels from three developmental stages (grain-filling kernels [FKs], mature kernels [MKs], and germinating kernels [GKs]) using a population of 159 recombinant inbred lines. We detected 625 annotated metabolites and mapped 3173, 3143, and 2644 metabolite quantitative trait loci (mQTLs) in FKs, MKs, and GKs, respectively. Only 52 mQTLs were mapped at all three stages, indicating the high stage specificity of the wheat kernel metabolome. Four candidate genes were functionally validated by in vitro enzymatic reactions and/or transgenic approaches in wheat, three of which mediated the tricin metabolic pathway. Metabolite flux efficiencies within the tricin pathway were evaluated, and superior candidate haplotypes were identified, comprehensively delineating the tricin metabolism pathway in wheat. Finally, additional wheat metabolic pathways were re-constructed by updating them to incorporate the 177 candidate genes identified in this study. Our work provides new information on variations in the wheat kernel metabolome and important molecular resources for improvement of wheat nutritional quality.


Assuntos
Locos de Características Quantitativas , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Valor Nutritivo/genética , Sementes/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Metaboloma/genética , Mapeamento Cromossômico , Metabolômica
16.
Plant Sci ; 328: 111583, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36608874

RESUMO

Whole-plant transpiration, controlled by plant hydraulics and stomatal movement, is regulated by endogenous and environmental signals, with the light playing a dominant role. Stomatal pore size continuously adjusts to changes in light intensity and quality to ensure optimal CO2 intake for photosynthesis on the one hand, together with minimal water loss on the other. The link between light and transpiration is well established, but the genetic knowledge of how guard cells perceive those signals to affect stomatal conductance is still somewhat limited. In the current study, we evaluated the role of two central light-responsive transcription factors; a bZIP-family transcription factor ELONGATED HYPOCOTYL5 (HY5) and the basic helix-loop-helix (BHLH) transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4), in the regulation of steady-state transpiration. We show that overexpression of PIF4 exclusively in guard cells (GCPIF4) decreases transpiration, and can restrain the high transpiration of the pif4 mutant. Expression of HY5 specifically in guard cells (GCHY5) had the opposite effect of enhancing transpiration rates of WT- Arabidopsis and tobacco plants and of the hy5 mutant in Arabidopsis. In addition, we show that GCHY5 can reverse the low transpiration caused by guard cell overexpression of the sugar sensor HEXOKINASE1 (HXK1, GCHXK), an established low transpiring genotype. Finally, we suggest that the GCHY5 reversion of low transpiration by GCHXK requires the auto-activation of the endogenous HY5 in other tissues. These findings support the existence of an ongoing diurnal regulation of transpiration by the light-responsive transcription factors HY5 and PIF4 in the stomata, which ultimately determine the whole-plant water use efficiency.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fitocromo/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Água/metabolismo , Regulação da Expressão Gênica de Plantas
17.
Plant Sci ; 333: 111748, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37230189

RESUMO

In the last decades, linkage mapping has help in the location of metabolite quantitative trait loci (QTL) in many species; however, this approach shows some limitations. Recently, thanks to the most recent advanced in high-throughput genotyping technologies like next-generation sequencing, metabolite genome-wide association study (mGWAS) has been proposed a powerful tool to identify the genetic variants in polygenic agrinomic traits. Fruit flavor is a complex interaction of aroma volatiles and taste being sugar and acid ratio key parameter for flavor acceptance. Here, we review recent progress of mGWAS in pinpoint gene polymorphisms related to flavor-related metabolites in fruits. Despite clear successes in discovering novel genes or regions associated with metabolite accumulation affecting sensory attributes in fruits, GWAS incurs in several limitations summarized in this review. In addition, in our own work, we performed mGWAS on 194 Citrus grandis accessions to investigate the genetic control of individual primary and lipid metabolites in ripe fruit. We have identified a total of 667 associations for 14 primary metabolites including amino acids, sugars, and organic acids, and 768 associations corresponding to 47 lipids. Furthermore, candidate genes related to important metabolites related to fruit quality such as sugars, organic acids and lipids were discovered.


Assuntos
Frutas , Estudo de Associação Genômica Ampla , Frutas/metabolismo , Mapeamento Cromossômico , Açúcares/metabolismo , Lipídeos/análise
18.
G3 (Bethesda) ; 14(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-37883711

RESUMO

Perennial grasses are important forage crops and emerging biomass crops and have the potential to be more sustainable grain crops. However, most perennial grass crops are difficult experimental subjects due to their large size, difficult genetics, and/or their recalcitrance to transformation. Thus, a tractable model perennial grass could be used to rapidly make discoveries that can be translated to perennial grass crops. Brachypodium sylvaticum has the potential to serve as such a model because of its small size, rapid generation time, simple genetics, and transformability. Here, we provide a high-quality genome assembly and annotation for B. sylvaticum, an essential resource for a modern model system. In addition, we conducted transcriptomic studies under 4 abiotic stresses (water, heat, salt, and freezing). Our results indicate that crowns are more responsive to freezing than leaves which may help them overwinter. We observed extensive transcriptional responses with varying temporal dynamics to all abiotic stresses, including classic heat-responsive genes. These results can be used to form testable hypotheses about how perennial grasses respond to these stresses. Taken together, these results will allow B. sylvaticum to serve as a truly tractable perennial model system.


Assuntos
Brachypodium , Humanos , Brachypodium/genética , Genoma de Planta , Biomassa , Transcriptoma , Estresse Fisiológico/genética
19.
Front Plant Sci ; 13: 1009956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36426148

RESUMO

Soil biosolarization (SBS) is an alternative technique for soil pest control to standard techniques such as soil fumigation and soil solarization (SS). By using both solar heating and fermentation of organic amendments, faster and more effective control of soilborne pathogens can be achieved. A circular economy may be created by using the residues of a given crop as organic amendments to biosolarize fields that produce that crop, which is termed circular soil biosolarization (CSBS). In this study, CSBS was employed by biosolarizing soil with amended tomato pomace (TP) residues and examining its impact on tomato cropping under conditions of abiotic stresses, specifically high salinity and nitrogen deficiency. The results showed that in the absence of abiotic stress, CSBS can benefit plant physiological performance, growth and yield relative to SS. Moreover, CSBS significantly mitigated the impacts of abiotic stress conditions. The results also showed that CSBS impacted the soil microbiome and plant metabolome. Mycoplana and Kaistobacter genera were found to be positively correlated with benefits to tomato plants health under abiotic stress conditions. Conversely, the relative abundance of the orders RB41, MND1, and the family Ellin6075 and were negatively correlated with tomato plants health. Moreover, several metabolites were significantly affected in plants grown in SS- and CSBS-treated soils under abiotic stress conditions. The metabolite xylonic acid isomer was found to be significantly negatively correlated with tomato plants health performance across all treatments. These findings improve understanding of the interactions between CSBS, soil ecology, and crop physiology under abiotic stress conditions.

20.
Plant Physiol ; 152(1): 245-54, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19939947

RESUMO

Tobacco (Nicotiana tabacum; C3) plants increase their water use efficiency (WUE) under abiotic stress and are suggested to show characteristics of C4 photosynthesis in stems, petioles, and transmitting tract cells. The tobacco stress-induced Aquaporin1 (NtAQP1) functions as both water and CO(2) channel. In tobacco plants, overexpression of NtAQP1 increases leaf net photosynthesis (A(N)), mesophyll CO(2) conductance, and stomatal conductance, whereas its silencing reduces root hydraulic conductivity (L(p)). Nevertheless, interaction between NtAQP1 leaf and root activities and its impact on plant WUE and productivity under normal and stress conditions have never been suggested. Thus, the aim of this study was to suggest a role for NtAQP1 in plant WUE, stress resistance, and productivity. Expressing NtAQP1 in tomato (Solanum lycopersicum) plants (TOM-NtAQP1) resulted in higher stomatal conductance, whole-plant transpiration, and A(N) under all conditions tested. In contrast to controls, where, under salt stress, L(p) decreased more than 3-fold, TOM-NtAQP1 plants, similar to maize (Zea mays; C4) plants, did not reduce L(p) dramatically (only by approximately 40%). Reciprocal grafting provided novel evidence for NtAQP1's role in preventing hydraulic failure and maintaining the whole-plant transpiration rate. Our results revealed independent, albeit closely related, NtAQP1 activities in roots and leaves. This dual activity, which increases the plant's water use and A(N) under optimal and stress conditions, resulted in improved WUE. Consequently, it contributed to the plant's stress resistance in terms of yield production under all tested conditions, as demonstrated in both tomato and Arabidopsis (Arabidopsis thaliana) plants constitutively expressing NtAQP1. The putative involvement of NtAQP1 in tobacco's C4-like photosynthesis characteristics is discussed.


Assuntos
Aquaporina 1/metabolismo , Nicotiana/metabolismo , Cloreto de Sódio/toxicidade , Estresse Fisiológico/fisiologia , Água/metabolismo , Aquaporina 1/genética , Ritmo Circadiano , Regulação da Expressão Gênica de Plantas/fisiologia , Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Transpiração Vegetal/efeitos dos fármacos , Transpiração Vegetal/fisiologia , Transdução de Sinais , Estresse Fisiológico/efeitos dos fármacos
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