Overexpression of Rice Gene Lsi1 (Low Silicon Gene 1) Enhances The Plant-Microbe Interaction Resulting In Improved Chilling Tolerance

Abstract Chilling is an environmental phenomenon that hampers the plant growth. Related studies are mainly on based on the aerial plant parts. While, below ground to rhizosphere microbiome have been neglected under low temperature stress. The overexpression of Lsi1 in Dular significantly enhances its proline concentration compared with wild type Dular. This overexpression phenomenon maintains the osmotic balance of cells through influx of Ca2+, K+, H+ and efflux of Na+. The calcium deposition and the activity of plasma membrane H+-ATPase determined in root tip was consistent with the obtained ion flux results. In addition, the high-throughput sequencing results showed significant variation among identified 84 genera in different rhizocompartments (rhizosphere, rhizoplane and endosphere). The identified bacteria were associated with photosynthesis, energy metabolism, nitrogen fixation and defense, which were significantly increased in overexpressed plant. While, the number of pathogenic microorganisms associating were significantly reduced. Our findings suggests that the stability of ion balance in overexpressed plant roots affects the structure of microbial community in soil. To conclude, the over expression of Lsi1 gene enhanced cold tolerance of rice and its underlying mechanisms were comprehensively analyzed which can further impart its role in the stress tolerant rice plants.

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The impact of biomass harvesting on phosphorus uptake by wetland plants

Water Science & Technology ◽

10.2166/wst.2001.0810 ◽

2001 ◽

Vol 44 (11-12) ◽

pp. 61-67 ◽

Cited By ~ 26

Author(s):

S-Y. Kim ◽

P.M. Geary

Keyword(s):

Plant Biomass ◽

Phosphorus Uptake ◽

P Uptake ◽

Plant Parts ◽

Biomass Harvesting ◽

Below Ground ◽

The Impact ◽

Total P ◽

Better Than ◽

P Removal

Two species of macrophytes, Baumea articulata and Schoenoplectus mucronatus, were examined for their capacity to remove phosphorus under nutrient-rich conditions. Forty large bucket systems with the two different species growing in two types of substrate received artificial wastewaters for nine months, simulating a constructed wetland (CW) under high loading conditions. Half of the plants growing in the topsoil and gravel substrates were periodically harvested whereas the other half remained intact. Plant tissue and substrate samples were regularly analysed to determine their phosphorus concentrations. With respect to phosphorus uptake and removal, the Schoenoplectus in the topsoil medium performed better than the Baumea. Biomass harvesting enhanced P uptake in the Schoenoplectus, however the effect was not significant enough to make an improvement on the overall P removal, due to the slow recovery of plants and regrowth of biomass after harvesting. From P partitioning, it was found that the topsoil medium was the major P pool, storing most of total P present in the system. Plant parts contributed only minor storage with approximately half of that P stored below ground in the plant roots. The overall net effect of harvesting plant biomass was to only remove less than 5% of total phosphorus present in the system.

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Nonlinear Blade Stability for a Scaled Autogyro Rotor at High Advance Ratios

Journal of the American Helicopter Society ◽

10.4050/jahs.65.012005 ◽

2020 ◽

Vol 65 (1) ◽

pp. 1-19

Author(s):

Djamel Rezgui ◽

Mark H. Lowenberg

Keyword(s):

High Speed ◽

Flow Speed ◽

Numerical Continuation ◽

Control Input ◽

Nonlinear Phenomenon ◽

Scaled Model ◽

Underlying Mechanisms ◽

Slowed Rotor ◽

The Stability ◽

Blade Pitch Angle

Despite current research advances in aircraft dynamics and increased interest in the slowed rotor concept for high-speed compound helicopters, the stability of autogyro rotors remains partially understood, particularly at lightly loaded conditions and high advance ratios. In autorotation, the periodic behavior of a rotor blade is a complex nonlinear phenomenon, further complicated by the fact that the rotor speed is not held constant. The aim of the analysis presented in this article is to investigate the underlying mechanisms that can lead to rotation-flap blade instability at high advance ratios for a teetering autorotating rotor. The stability analysis was conducted via wind tunnel tests of a scaled autogyro model combined with numerical continuation and bifurcation analysis. The investigation assessed the effect of varying the flow speed, blade pitch angle, and rotor shaft tilt relative to the flow on the rotor performance and blade stability. The results revealed that rotor instability in autorotation is associated with the existence of fold bifurcations, which bound the control-input and design parameter space within which the rotor can autorotate. This instability occurs at a lightly loaded condition and at advance ratios close to 1 for the scaled model. Finally, it was also revealed that the rotor inability to autorotate was driven by blade stall.

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The collapse of genetic incompatibilities in a hybridizing population

10.1101/2021.01.08.425971 ◽

2021 ◽

Author(s):

Tianzhu Xiong ◽

James L MALLET

Keyword(s):

Gene Regulation ◽

Reproductive Isolation ◽

Genetic Drift ◽

Recombination Rate ◽

Time Scale ◽

Genetic Incompatibility ◽

Genetic Process ◽

Underlying Mechanisms ◽

The Stability

Genetic incompatibility has long been considered to be a hallmark of speciation due to its role in reproductive isolation. Previous analyses of the stability of epistatic incompatibility show that it is subject to collapse upon hybridization. In the present work, we derive explicitly the distribution of the lifespan of two-locus incompatibilities, and show that genetic drift, along with recombination, is critical in determining the time scale of collapse. The first class of incompatibilities, where derived alleles separated in parental populations act antagonistically in hybrids, survive longer in smaller populations when incompatible alleles are (co)dominant and tightly linked, but collapse more quickly when they are recessive. The second class of incompatibilities, where fitness is reduced by disrupting co-evolved elements in gene regulation systems, collapse on a time scale proportional to the exponential of effective recombination rate. Overall, our result suggests that the effects of genetic drift and recombination on incompatibility's lifespan depend strongly on the underlying mechanisms of incompatibilities. As the time scale of collapse is usually shorter than the time scale of establishing a new incompatibility, the observed level of genetic incompatibilities in a particular hybridizing population may be shaped more by the collapse than by their initial accumulation. Therefore, a joint theory of accumulation-erosion of incompatibilities is in need to fully understand the genetic process under speciation with hybridization.

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Longitudinal profiling of the lung microbiome in the AERIS study demonstrates repeatability of bacterial and eosinophilic COPD exacerbations

Thorax ◽

10.1136/thoraxjnl-2017-210408 ◽

2018 ◽

Vol 73 (5) ◽

pp. 422-430 ◽

Cited By ~ 62

Author(s):

David Mayhew ◽

Nathalie Devos ◽

Christophe Lambert ◽

James R Brown ◽

Stuart C Clarke ◽

...

Keyword(s):

Disease Severity ◽

High Throughput Sequencing ◽

Respiratory Infections ◽

Markov Chain Model ◽

Chain Model ◽

Copd Exacerbations ◽

Lung Microbiome ◽

Registration Number ◽

The Stability ◽

Over Time

BackgroundAlterations in the composition of the lung microbiome associated with adverse clinical outcomes, known as dysbiosis, have been implicated with disease severity and exacerbations in COPD.ObjectiveTo characterise longitudinal changes in the lung microbiome in the AERIS study (Acute Exacerbation and Respiratory InfectionS in COPD) and their relationship with associated COPD outcomes.MethodsWe surveyed 584 sputum samples from 101 patients with COPD to analyse the lung microbiome at both stable and exacerbation time points over 1 year using high-throughput sequencing of the 16S ribosomal RNA gene. We incorporated additional lung microbiology, blood markers and in-depth clinical assessments to classify COPD phenotypes.ResultsThe stability of the lung microbiome over time was more likely to be decreased in exacerbations and within individuals with higher exacerbation frequencies. Analysis of exacerbation phenotypes using a Markov chain model revealed that bacterial and eosinophilic exacerbations were more likely to be repeated in subsequent exacerbations within a subject, whereas viral exacerbations were not more likely to be repeated. We also confirmed the association of bacterial genera, including Haemophilus and Moraxella, with disease severity, exacerbation events and bronchiectasis.ConclusionsSubtypes of COPD have distinct bacterial compositions and stabilities over time. Some exacerbation subtypes have non-random probabilities of repeating those subtypes in the future. This study provides insights pertaining to the identification of bacterial targets in the lung and biomarkers to classify COPD subtypes and to determine appropriate treatments for the patient.Trial registration numberResults, NCT01360398.

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Dual functions of Rack1 in regulating Hedgehog pathway

Cell Death and Differentiation ◽

10.1038/s41418-020-0563-7 ◽

2020 ◽

Vol 27 (11) ◽

pp. 3082-3096 ◽

Cited By ~ 1

Author(s):

Yan Li ◽

Xiaohan Sun ◽

Dongqing Gao ◽

Yan Ding ◽

Jinxiao Liu ◽

...

Keyword(s):

Mammalian Cells ◽

Cellular Localization ◽

Multiple Roles ◽

Dual Roles ◽

Cubitus Interruptus ◽

Trimeric Complex ◽

Physiological Processes ◽

Underlying Mechanisms ◽

The Stability ◽

Fine Tune

Abstract Hedgehog (Hh) pathway plays multiple roles in many physiological processes and its dysregulation leads to congenital disorders and cancers. Hh regulates the cellular localization of Smoothened (Smo) and the stability of Cubitus interruptus (Ci) to fine-tune the signal outputs. However, the underlying mechanisms are still unclear. Here, we show that the scaffold protein Rack1 plays dual roles in Hh signaling. In the absence of Hh, Rack1 promotes Ci and Cos2 to form a Ci–Rack1–Cos2 complex, culminating in Slimb-mediated Ci proteolysis. In the presence of Hh, Rack1 dissociates from Ci–Rack1–Cos2 complex and forms a trimeric complex with Smo and Usp8, leading to Smo deubiquitination and cell surface accumulation. Furthermore, we find the regulation of Rack1 on Hh pathway is conserved from Drosophila to mammalian cells. Our findings demonstrate that Rack1 plays dual roles during Hh signal transduction and provide Rack1 as a potential drug target for Hh-related diseases.

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Redox-Responsive Transcription Factor 1 (RRFT1) Is Involved in Extracellular ATP-Regulated Arabidopsis thaliana Seedling Growth

Plant and Cell Physiology ◽

10.1093/pcp/pcaa014 ◽

2020 ◽

Vol 61 (4) ◽

pp. 685-698 ◽

Cited By ~ 2

Author(s):

Ruojia Zhu ◽

Xiaoxia Dong ◽

Yingying Xue ◽

Jiawei Xu ◽

Aiqi Zhang ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Adenosine Triphosphate ◽

Seedling Growth ◽

Growth And Development ◽

High Throughput Sequencing ◽

Root Tip ◽

Loss Of Function ◽

Redox Responsive ◽

Transcription Factor 1

Abstract Extracellular adenosine triphosphate (eATP) is an apoplastic signaling molecule that plays an essential role in the growth and development of plants. Arabidopsis seedlings have been reported to respond to eATP; however, the downstream signaling components are still not well understood. In this study, we report that an ethylene-responsive factor, Redox-Responsive Transcription Factor 1 (RRTF1), is involved in eATP-regulated Arabidopsis thaliana seedling growth. Exogenous adenosine triphosphate inhibited green seedling root growth and induced hypocotyl bending of etiolated seedlings. RRTF1 loss-of-function mutant (rrtf1) seedlings showed decreased responses to eATP, while its complementation or overexpression led to recovered or increased eATP responsiveness. RRTF1 was expressed rapidly after eATP stimulation and then migrated into the nuclei of root tip cells. eATP-induced auxin accumulation in root tip or hypocotyl cells was impaired in rrtf1. Chromatin immunoprecipitation and high-throughput sequencing results indicated that eATP induced some genes related to cell growth and development in wild type but not in rrtf1 cells. These results suggest that RRTF1 may be involved in eATP signaling by regulating functional gene expression and cell metabolism in Arabidopsis seedlings.

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Carbon resource sharing and rhizome expansion of Phalaris aquatica plants in grazed pastures

Functional Plant Biology ◽

10.1071/fp04098 ◽

2005 ◽

Vol 32 (1) ◽

pp. 79 ◽

Cited By ~ 6

Author(s):

Brendan R. Cullen ◽

David F. Chapman ◽

Paul E. Quigley

Keyword(s):

Resource Sharing ◽

Seasonal Pattern ◽

Soil Surface ◽

Deep Roots ◽

Phalaris Aquatica ◽

Plant Parts ◽

Grazed Pastures ◽

Below Ground ◽

Grazing Systems ◽

Western Victoria

The patterns of carbon (C) resource sharing and new rhizome development in phalaris (Phalaris aquatica L. cv. Australian) were examined in grazed pastures in western Victoria. The seasonal pattern of new rhizome growth was similar under the four grazing systems tested. New rhizome production was infrequent but concentrated in winter. The phalaris plants maintained more than 1600 kg DW ha–1 of non-assimilating material beneath the soil surface (0–5 cm). Gaseous 14C was fed into plants in the field to determine if these below ground structures continued to be supported by the C assimilating tillers. The results indicated that the primary tiller does provide C to support the growth of secondary and tertiary tillers derived from its axillary buds. There was some evidence that C was exported from the fed tiller to non-assimilating plant structures. The old reproductive tiller bases (from which the assimilating tillers originate) received some C support, suggesting that this was maintained because it had deep roots attached. C export to older plant parts declined, which may lead to plant fragmentation.

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Sustained ER stress promotes hyperglycemia by increasing glucagon action through the deubiquitinating enzyme USP14

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1907288116 ◽

2019 ◽

Vol 116 (43) ◽

pp. 21732-21738 ◽

Cited By ~ 4

Author(s):

Bin Liu ◽

Zhijian Zhang ◽

Yanyun Hu ◽

Yan Lu ◽

Duanzhuo Li ◽

...

Keyword(s):

Er Stress ◽

Metabolic Diseases ◽

Low Grade ◽

Deubiquitinating Enzyme ◽

Obese Mice ◽

Hepatic Gluconeogenesis ◽

Regulatory Pathways ◽

Underlying Mechanisms ◽

The Stability ◽

Glucose Output

Endoplasmic reticulum (ER) stress plays an important role in metabolic diseases like obesity and type 2 diabetes mellitus (T2DM), although the underlying mechanisms and regulatory pathways remain to be elucidated. Here, we induced chronic low-grade ER stress in lean mice to levels similar to those in high-fat diet (HFD)–fed obese mice and found that it promoted hyperglycemia due to enhanced hepatic gluconeogenesis. Mechanistically, sustained ER stress up-regulated the deubiquitinating enzyme ubiquitin-specific peptidase 14 (USP14), which increased the stability and levels of 3′,5′-cyclic monophosphate–responsive element binding (CREB) protein (CBP) to enhance glucagon action and hepatic gluconeogenesis. Exogenous overexpression of USP14 in the liver significantly increased hepatic glucose output. Consistent with this, liver-specific knockdown of USP14 abrogated the effects of ER stress on glucose metabolism, and also improved hyperglycemia and glucose intolerance in obese mice. In conclusion, our findings show a mechanism underlying ER stress-induced disruption of glucose homeostasis, and present USP14 as a potential therapeutic target against T2DM.

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Estimating above- and below-ground macrophyte production in Scirpus tidal marshes

Canadian Journal of Botany ◽

10.1139/b88-059 ◽

1988 ◽

Vol 66 (2) ◽

pp. 368-374 ◽

Cited By ~ 11

Author(s):

Jean-François Giroux ◽

Jean Bédard

Keyword(s):

Standing Crop ◽

Belowground Biomass ◽

Tidal Marshes ◽

Optimal Size ◽

Lawrence Estuary ◽

Plant Parts ◽

Peak Standing Crop ◽

Below Ground ◽

The Difference ◽

St Lawrence Estuary

Different methods to estimate primary production of Scirpus marshes of the St. Lawrence estuary were compared. Quadrats 25 × 25 cm and cores 10 cm in diameter were found to be the optimal size to sample above- and below-ground standing crops, respectively. Ash content for different plant parts of various species was measured to obtain more accurate estimates of organic matter. A series of allometric equations relating stem height and mass were developed to estimate aerial standing crop from permanent nondestructively sampled plots. This method, however, overestimated standing crop compared with the destructive (harvest) method. The relationship between the above- and below-ground standing crop was also determined for the dominant species and used to predict belowground biomass without destructive sampling. Finally, the Smalley method provided the best estimates of net annual above- and below-ground production when losses attributed to decomposition were not considered. For less intensive studies, however, the methods based on peak standing crop and on the difference between maximum and minimum biomass would yield good approximations of above- and below-ground production.

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Study of Gas Production by Anaerobic Fermentation and Microbial Community Changes by In-Situ Microaerobic Desulphurization

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2020.1992517 ◽

2020 ◽

Vol 14 (4) ◽

pp. 517-523

Author(s):

Yan Zhou ◽

Hucheng Liu ◽

Wei Kou ◽

Lijie Shao ◽

Peihan Liu ◽

...

Keyword(s):

High Throughput Sequencing ◽

High Efficiency ◽

Anaerobic Fermentation ◽

Low Cost ◽

Total Solid ◽

Common Species ◽

Gas Production ◽

High Concentration ◽

Fermentation System ◽

The Stability

The enhancement of biogas quality at low cost and high efficiency process was one of the purposes of biogas engineering. In this work, we designed a reactor for microaerobic desulphurization. We used this reactor to study the anaerobic fermentation in systems that used cow manure with total solid (TS) concentrations of 18.5%, 15% and 10%. The influence of anaerobic fermentation on the stability of gas production and the characteristics of the gas produced with different concentrations of fermentation materials was studied. The strain structure of the fermentation system was obtained by high-throughput sequencing and taxonomy was compared. The H2S removal results showed that the average rates of the H2S removal in concentrations of fermentation materials of 18.5%, 15%, and 10% TS were 99.2%, 97.8%, and 78.8%, respectively. 16SrRNA sequencing was performed in different fermented samples as well as a comparison between samples in order to determine the number of unique species (NUS) and the number of common species (NCS). By comparing TS 18.5 with TS 15 and TS 10 samples, it was determined that under fermentation conditions, NUS were 113 and 106, respectively. Whereas NUS were 31 and 41, respectively, when comparing TS 15 and TS 10. These demonstrated that the number of strain species in the fermentation system with TS 18.5% was far more than those found in the systems with low concentration of fermentation. Also, the ability for disturbance resistance of the microaerobic desulphurization system was stronger at high concentration of the fermentation.

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