scholarly journals Micrografting Provides Evidence for Systemic Regulation of Sulfur Metabolism between Shoot and Root

Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1729
Author(s):  
Ilaria Forieri ◽  
Rasha Aref ◽  
Markus Wirtz ◽  
Rüdiger Hell

The uptake of sulfate by roots and its reductive assimilation mainly in the leaves are not only essential for plant growth and development but also for defense responses against biotic and abiotic stresses. The latter functions result in stimulus-induced fluctuations of sulfur demand at the cellular level. However, the maintenance and acclimation of sulfur homeostasis at local and systemic levels is not fully understood. Previous research mostly focused on signaling in response to external sulfate supply to roots. Here we apply micrografting of Arabidopsis wildtype knock-down sir1-1 mutant plants that suffer from an internally lowered reductive sulfur assimilation and a concomitant slow growth phenotype. Homografts of wildtype and sir1-1 confirm the hallmarks of non-grafted sir1-1 mutants, displaying substantial induction of sulfate transporter genes in roots and sulfate accumulation in shoots. Heterografts of wildtype scions and sir1-1 rootstocks and vice versa, respectively, demonstrate a dominant role of the shoot over the root with respect to sulfur-related gene expression, sulfate accumulation and organic sulfur metabolites, including the regulatory compound O-acetylserine. The results provide evidence for demand-driven control of the shoot over the sulfate uptake system of roots under sulfur-sufficient conditions, allowing sulfur uptake and transport to the shoot for dynamic responses.

2020 ◽  
Author(s):  
Sibylle Bauer ◽  
Elisabeth Georgii ◽  
Birgit Lange ◽  
Rafał P. Maksym ◽  
Robert Janowski ◽  
...  

AbstractSalicylic acid (SA) is a central signaling molecule in development and defense, therefore its levels are tightly controlled. One control mechanism is conjugation with sugar moieties by UDP glucosyltransferases (UGTs). In Arabidopsis, UGT76B1, UGT74F1, and UGT74F2 are known to glucosylate SA. We show that these are the main SA UGTs in leaves, since only marginal levels of SA glucosides were found in a triple loss-of-function mutant. Analyzing transcriptomes, metabolite levels, and phenotypes of a full combinatorial set of loss-of-function mutants, we resolved the mutual relationships and the individual roles of these enzymes in SA homeostasis. The strongest gene expression changes were observed for the ugt76b1 ugt74f1 double mutant, which downregulated developmental genes and most pronouncedly upregulated cell death-related genes. Among the single mutants, ugt76b1 specifically exhibited increased production of reactive oxygen species, increased resistance to infection, and early senescence. Likewise, higher-order mutations confirmed the dominant role of UGT76B1 in controlling SA levels and thereby the expression of biotic stress response genes. Both UGT74F1 and UGT74F2 affected UGT76B1 expression. However, while UGT76B1 and UGT74F1 produced SA-2-O-β-glucoside, UGT74F2 did not contribute there substantially. Instead, UGT74F2 acted independently of UGT74F1, decreasing steady-state SA levels by producing salicyloyl glucose ester. Remarkably, this did not restrict defense responses. In contrast, UGT74F1 interacted with UGT76B1 in suppressing defense responses. Nevertheless, a benzothiadiazole-triggered defense scenario induced only UGT76B1, whereas UGT74F1 was linked to controlling abiotic stress responses. All three enzymes form a network that, in concert with other UGTs, regulates expression of developmental and stress-related genes.One sentence summaryThe salicylic acid glucosylating enzymes of Arabidopsis leaves are crucial for salicylic acid homeostasis and combinatorially impact defense responses and developmental processes.


2013 ◽  
Vol 18 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Robert J. Barth

Abstract Scientific findings have indicated that psychological and social factors are the driving forces behind most chronic benign pain presentations, especially in a claim context, and are relevant to at least three of the AMA Guides publications: AMA Guides to Evaluation of Disease and Injury Causation, AMA Guides to Work Ability and Return to Work, and AMA Guides to the Evaluation of Permanent Impairment. The author reviews and summarizes studies that have identified the dominant role of financial, psychological, and other non–general medicine factors in patients who report low back pain. For example, one meta-analysis found that compensation results in an increase in pain perception and a reduction in the ability to benefit from medical and psychological treatment. Other studies have found a correlation between the level of compensation and health outcomes (greater compensation is associated with worse outcomes), and legal systems that discourage compensation for pain produce better health outcomes. One study found that, among persons with carpal tunnel syndrome, claimants had worse outcomes than nonclaimants despite receiving more treatment; another examined the problematic relationship between complex regional pain syndrome (CRPS) and compensation and found that cases of CRPS are dominated by legal claims, a disparity that highlights the dominant role of compensation. Workers’ compensation claimants are almost never evaluated for personality disorders or mental illness. The article concludes with recommendations that evaluators can consider in individual cases.


Author(s):  
D.Sh. Macharadze

В обзорной статье приведены данные по распространенности респираторной аллергии - аллергического ринита и бронхиальной астмы на юге России, опубликованные за последние десятилетия. Показана доминирующая роль пыльцевой аллергии практически во всем южном регионе России. В Чеченской Республике у больных респираторной аллергией обнаружена сходная частота встречаемости сенсибилизации к клещам домашней пыли и пыльце злаковых трав (51,1 и 52,5 соответственно), тогда как сенсибилизация к пыльце амброзии и полыни встречалась в 3 раза реже (26,6 и 20,7 соответственно) по сравнению с соседними регионами юга России. Эти данные демонстрируют климатогеографические, экологические и другие региональные особенности в распространении респираторной аллергии.The review article presents data on the prevalence of respiratory allergy - allergic rhinitis and bronchial asthma in southern Russia, published over the past decades. The dominant role of pollen allergy is shown in almost the entire southern region of Russia. In the Chechen Republic, sensitization to house dust mites and grass pollen was found in patients with respiratory allergy equally (51.1 and 52.5, respectively), whereas ragweed and mugwort sensitization was 3 times less (26.6 and 20.7, respectively) compared with the neighboring regions of southern Russia. These data demonstrate climate-geographical, environmental and other regional features in the prevalence of respiratory allergies.


Wacana Publik ◽  
2019 ◽  
Vol 12 (02) ◽  
Author(s):  
Syamsul Ma'arif

After had being carried out nationalization and hostility against west countries, the New Order regime made important decision to change Indonesia economic direction from etatism system to free market economy. A set of policies were taken in order private sector could play major role in economic. However, when another economic sectors were reformed substantially, effords to reform the State Owned Enterprises had failed. The State Owned Enterprise, in fact, remained to play dominant role like early years of guided democracy era. Role of the State Owned Enterprises was more and more powerfull). The main problem of reforms finally lied on reality that vested interest of bureaucrats (civil or military) was so large that could’nt been overcome. 


Author(s):  
Ildar Garipzanov

The concluding chapter highlights how the cultural history of graphic signs of authority in late antiquity and the early Middle Ages encapsulated the profound transformation of political culture in the Mediterranean and Europe from approximately the fourth to ninth centuries. It also reflects on the transcendent sources of authority in these historical periods, and the role of graphic signs in highlighting this connection. Finally, it warns that, despite the apparent dominant role of the sign of the cross and cruciform graphic devices in providing access to transcendent protection and support in ninth-century Western Europe, some people could still employ alternative graphic signs deriving from older occult traditions in their recourse to transcendent powers.


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Fangwei Yu ◽  
Shenyun Wang ◽  
Wei Zhang ◽  
Hong Wang ◽  
Li Yu ◽  
...  

Abstract The members of myeloblastosis transcription factor (MYB TF) family are involved in the regulation of biotic and abiotic stresses in plants. However, the role of MYB TF in phosphorus remobilization remains largely unexplored. In the present study, we show that an R2R3 type MYB transcription factor, MYB103, is involved in phosphorus (P) remobilization. MYB103 was remarkably induced by P deficiency in cabbage (Brassica oleracea var. capitata L.). As cabbage lacks the proper mutant for elucidating the mechanism of MYB103 in P deficiency, another member of the crucifer family, Arabidopsis thaliana was chosen for further study. The transcript of its homologue AtMYB103 was also elevated in response to P deficiency in A. thaliana, while disruption of AtMYB103 (myb103) exhibited increased sensitivity to P deficiency, accompanied with decreased tissue biomass and soluble P concentration. Furthermore, AtMYB103 was involved in the P reutilization from cell wall, as less P was released from the cell wall in myb103 than in wildtype, coinciding with the reduction of ethylene production. Taken together, our results uncover an important role of MYB103 in the P remobilization, presumably through ethylene signaling.


2011 ◽  
Vol 25 (1) ◽  
pp. 1-14 ◽  
Author(s):  
W. Edward Visser ◽  
Edith C. H. Friesema ◽  
Theo J. Visser

The effects of thyroid hormone (TH) on development and metabolism are exerted at the cellular level. Metabolism and action of TH take place intracellularly, which require transport of the hormone across the plasma membrane. This process is mediated by TH transporter proteins. Many TH transporters have been identified at the molecular level, although a few are classified as specific TH transporters, including monocarboxylate transporter (MCT)8, MCT10, and organic anion-transporting polypeptide 1C1. The importance of TH transporters for physiology has been illustrated dramatically by the causative role of MCT8 mutations in males with psychomotor retardation and abnormal serum TH concentrations. Although Mct8 knockout animals have provided insight in the mechanisms underlying parts of the endocrine phenotype, they lack obvious neurological abnormalities. Thus, the pathogenesis of the neurological abnormalities in males with MCT8 mutations is not fully understood. The prospects of identifying other transporters and transporter-based syndromes promise an exciting future in the TH transporter field.


2021 ◽  
Vol 22 (5) ◽  
pp. 2435
Author(s):  
Marzia Beccaccioli ◽  
Manuel Salustri ◽  
Valeria Scala ◽  
Matteo Ludovici ◽  
Andrea Cacciotti ◽  
...  

Fusarium verticillioides causes multiple diseases of Zea mays (maize) including ear and seedling rots, contaminates seeds and seed products worldwide with toxic chemicals called fumonisins. The role of fumonisins in disease is unclear because, although they are not required for ear rot, they are required for seedling diseases. Disease symptoms may be due to the ability of fumonisins to inhibit ceramide synthase activity, the expected cause of lipids (fatty acids, oxylipins, and sphingolipids) alteration in infected plants. In this study, we explored the impact of fumonisins on fatty acid, oxylipin, and sphingolipid levels in planta and how these changes affect F. verticillioides growth in maize. The identity and levels of principal fatty acids, oxylipins, and over 50 sphingolipids were evaluated by chromatography followed by mass spectrometry in maize infected with an F. verticillioides fumonisin-producing wild-type strain and a fumonisin-deficient mutant, after different periods of growth. Plant hormones associated with defense responses, i.e., salicylic and jasmonic acid, were also evaluated. We suggest that fumonisins produced by F. verticillioides alter maize lipid metabolism, which help switch fungal growth from a relatively harmless endophyte to a destructive necrotroph.


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