In situ translocation of volicitin by beet armyworm larvae to maize and systemic immobility of the herbivore elicitor in planta

AbstractSilicon is reported to reduce the toxic effects of Al on root elongation but the in planta mechanism by which this occurs remains unclear. Using seedlings of soybean (Glycine max) and sorghum (Sorghum bicolor), we examined the effect of up to 2 mM Si on root elongation rate (RER) in Al-toxic nutrient solutions. Synchrotron-based low energy X-ray fluorescence (LEXRF) was then used for the in situ examination of the distribution of Al and Si within cross-sections cut from the apical tissues of sorghum roots. The addition of Si potentially increased RER in Al-toxic solutions, with RER being up to ca. 0.3 mm h−1 (14 %) higher for soybean and ca. 0.2 mm h−1 (17 %) higher for sorghum relative to solutions without added Si. This improvement in RER could not be attributed to a change in Al-chemistry of the bulk nutrient solution, nor was it due to a change in the concentration of Al within the apical (0-10 mm) root tissues. Using LEXRF to examine sorghum, it was demonstrated that in roots exposed to both Al and Si, much of the Al was co-located with Si in the mucigel and outer apoplast. These observations suggest that Si reduces the toxicity of Al in planta through formation of Al-Si complexes in mucigel and outer cellular tissues, thereby decreasing the binding of Al to the cell wall where it is known to inhibit wall loosening as required for cell elongation.

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A minimally disruptive method for measuring water potential in planta using hydrogel nanoreporters

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2008276118 ◽

2021 ◽

Vol 118 (23) ◽

pp. e2008276118

Author(s):

Piyush Jain ◽

Weizhen Liu ◽

Siyu Zhu ◽

Christine Yao-Yun Chang ◽

Jeff Melkonian ◽

...

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Water Status ◽

Resonance Energy ◽

Field Measurements ◽

Leaf Water ◽

Plant Water Status ◽

Plant Water ◽

In Planta

Leaf water potential is a critical indicator of plant water status, integrating soil moisture status, plant physiology, and environmental conditions. There are few tools for measuring plant water status (water potential) in situ, presenting a critical barrier for developing appropriate phenotyping (measurement) methods for crop development and modeling efforts aimed at understanding water transport in plants. Here, we present the development of an in situ, minimally disruptive hydrogel nanoreporter (AquaDust) for measuring leaf water potential. The gel matrix responds to changes in water potential in its local environment by swelling; the distance between covalently linked dyes changes with the reconfiguration of the polymer, leading to changes in the emission spectrum via Förster Resonance Energy Transfer (FRET). Upon infiltration into leaves, the nanoparticles localize within the apoplastic space in the mesophyll; they do not enter the cytoplasm or the xylem. We characterize the physical basis for AquaDust’s response and demonstrate its function in intact maize (Zea mays L.) leaves as a reporter of leaf water potential. We use AquaDust to measure gradients of water potential along intact, actively transpiring leaves as a function of water status; the localized nature of the reporters allows us to define a hydraulic model that distinguishes resistances inside and outside the xylem. We also present field measurements with AquaDust through a full diurnal cycle to confirm the robustness of the technique and of our model. We conclude that AquaDust offers potential opportunities for high-throughput field measurements and spatially resolved studies of water relations within plant tissues.

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Faculty Opinions recommendation of In planta quantification of endoreduplication using fluorescent in situ hybridization (FISH).

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.10807956.11714054 ◽

2011 ◽

Author(s):

Lieven De Veylder

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

In Planta

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Interactions between dietary flavonoids and the gut microbiome: a comprehensive review

British Journal Of Nutrition ◽

10.1017/s0007114521003627 ◽

2021 ◽

pp. 1-15

Author(s):

Mostafa Hassan Baky ◽

Mostafa Elshahed ◽

Ludger Wessjohann ◽

Mohamed A. Farag

Keyword(s):

Gut Microbiota ◽

Chemical Structure ◽

Biological Activities ◽

Physiological Changes ◽

Gi Tract ◽

In Planta ◽

Natural Polyphenol ◽

Biotransformation Products ◽

Dietary Flavonoids

Abstract Flavonoids are natural polyphenol secondary metabolites that are widely produced in planta. Flavonoids are ubiquities in human dietary intake and exhibit a myriad of health benefits. Flavonoids-induced biological activities are strongly influenced by their in situ availability in the human GI tract, as well as the levels of which are modulated by interaction with the gut bacteria. As such, assessing flavonoids–microbiome interactions is considered a key to understand their physiological activities. Here, we review the interaction between the various classes of dietary flavonoids (flavonols, flavones, flavanones, isoflavones, flavan-3-ols and anthocyanins) and gut microbiota. We aim to provide a holistic overview of the nature and identity of flavonoids on diet and highlight how flavonoids chemical structure, metabolism and impact on humans and their microbiomes are interconnected. Emphasis is placed on how flavonoids and their biotransformation products affect gut microbiota population, influence gut homoeostasis and induce measurable physiological changes and biological benefits.

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A minimally disruptive method for measuring water potential in-planta using hydrogel nanoreporters

10.1101/2020.05.29.122507 ◽

2020 ◽

Author(s):

Piyush Jain ◽

Weizhen Liu ◽

Siyu Zhu ◽

Jeff Melkonian ◽

Duke Pauli ◽

...

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Water Status ◽

Resonance Energy ◽

Field Measurements ◽

Leaf Water ◽

Plant Water Status ◽

Plant Water ◽

In Planta

AbstractLeaf water potential is a critical indicator of plant water status, integrating soil moisture status, plant physiology, and environmental conditions. There are few tools for measuring plant water status (water potential) in situ, presenting a critical barrier for the development of appropriate phenotyping (measurement) methods for crop development and modeling efforts aimed at understanding water transport in plants. Here, we present the development of an in situ, minimally-disruptive hydrogel nanoreporter (AquaDust) for measuring leaf water potential. The gel matrix responds to changes in water potential in its local environment by swelling; the distance between covalently linked dyes changes with the reconfiguration of the polymer, leading to changes in the emission spectrum via Fluorescence Resonance Energy Transfer (FRET). Upon infiltration into leaves, the nanoparticles localize within the apoplastic space in the mesophyll; they do not enter the cytoplast or the xylem. We characterize the physical basis for AquaDust’s response and demonstrate its function in intact maize (Zea mays L.) leaves as a reporter of leaf water potential. We use AquaDust to measure gradients of water potential along intact, actively transpiring leaves as a function of water status; the localized nature of the reporters allows us to define a hydraulic model that distinguishes resistances inside and outside the xylem. We also present field measurements with AquaDust through a full diurnal cycle to confirm the robustness of the technique and of our model. We conclude that AquaDust offers potential opportunities for high-throughput, field measurements and spatially resolved studies of water relations within plant tissues.

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Simultaneous specific in planta visualization of root-colonizing fungi using fluorescence in situ hybridization (FISH)

Mycorrhiza ◽

10.1007/s00572-013-0533-8 ◽

2013 ◽

Vol 24 (4) ◽

pp. 259-266 ◽

Cited By ~ 16

Author(s):

Pál Vági ◽

Dániel G. Knapp ◽

Annamária Kósa ◽

Diána Seress ◽

Áron N. Horváth ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

In Planta

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A Wheat β-Patchoulene Synthase Confers Resistance against Herbivory in Transgenic Arabidopsis

Genes ◽

10.3390/genes10060441 ◽

2019 ◽

Vol 10 (6) ◽

pp. 441 ◽

Cited By ~ 1

Author(s):

Qingyu Pu ◽

Jin Liang ◽

Qinqin Shen ◽

Jingye Fu ◽

Zhien Pu ◽

...

Keyword(s):

Gene Expression ◽

Catalytic Mechanism ◽

Transgenic Arabidopsis ◽

Triticum Aestivum L ◽

Site Directed Mutagenesis ◽

Beet Armyworm ◽

Terpene Synthase ◽

In Planta ◽

Terpene Synthases ◽

Sesquiterpene Synthase

Terpenoids play important roles in plant defense. Although some terpene synthases have been characterized, terpenoids and their biosynthesis in wheat (Triticum aestivum L.) still remain largely unknown. Here, we describe the identification of a terpene synthase gene in wheat. It encodes a sesquiterpene synthase that catalyzes β-patchoulene formation with E,E-farnesyl diphosphate (FPP) as the substrate, thus named as TaPS. TaPS exhibits inducible expression in wheat in response to various elicitations. Particularly, alamethicin treatment strongly induces TaPS gene expression and β-patchoulene accumulation in wheat. Overexpression of TaPS in Arabidopsis successfully produces β-patchoulene, verifying the biochemical function of TaPS in planta. Furthermore, these transgenic Arabidopsis plants exhibit resistance against herbivory by repelling beet armyworm larvae feeding, thereby indicating anti-herbivory activity of β-patchoulene. The catalytic mechanism of TaPS is also explored by homology modeling and site-directed mutagenesis. Two key amino acids are identified to act in protonation and stability of intermediates and product formation. Taken together, one wheat sesquiterpene synthase is identified as β-patchoulene synthase. TaPS exhibits inducible gene expression and the sesquiterpene β-patchoulene is involved in repelling insect infestation.

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Comparison of in vitro and in planta toxicity of Vip3A for lepidopteran herbivores

10.1101/829895 ◽

2019 ◽

Author(s):

Muhammad Hassaan Khan ◽

Georg Jander ◽

Zahid Mukhtar ◽

Muhammad Arshad ◽

Muhammad Sarwar ◽

...

Keyword(s):

Transgenic Plants ◽

Transgenic Tobacco ◽

Crop Production ◽

Artificial Diet ◽

Synergistic Effects ◽

Corn Earworm ◽

Tobacco Budworm ◽

Beet Armyworm ◽

Dependent Manner ◽

In Planta

AbstractAgricultural pest infestation is as old as domestication of food crops and contributes a major share to the cost of crop production. Transgenic production of Vip3A, an insecticidal protein from Bacillus thuringiensis, effectively controls lepidopteran pests. A synthetic vip3A gene was evaluated its efficacy against Spodoptera litura (cotton leafworm), Spodoptera exigua (beet armyworm), Spodoptera frugiperda (fall armyworm), Helicoverpa armigera (cotton bollworm), Helicoverpa zea (corn earworm), Heliothis virescens (tobacco budworm), and Manduca sexta (tobacco hornworm). In artificial diet assays, the Vip3A concentration causing 50% mortality was H. zea > H. virescens > S. exigua > H. armigera > M. sexta > S. frugiperda > S. litura. In contrast, on vip3A transgenic tobacco the order of resistance (time until 50% lethality) was M. sexta > H. virescens > S. litura > H. zea > H. armigera > S. exigua > S. frugiperda. There was no significant correlation between the artificial diet and transgenic tobacco effects. Notably, the two insect species that are best-adapted for growth on tobacco, M. sexta and H. virescens, showed the greatest tolerance of vip3A-transgenic tobacco. This may indicate synergistic effects of Vip3A and endogenous plant defense mechanisms, e.g. nicotine, to which M. sexta and H. virescens would have greater resistance. Together, our results show that artificial diet assays are a poor predictor of Vip3A efficacy in transgenic plants, lepidopteran species vary in their sensitivity to Vip3A in diet-dependent manner, and that host plant adaptation of the targeted herbivores should be considered when designing transgenic plants for pest control.

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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