scholarly journals Expression of TaTAR2.3-1B, TaYUC9-1 and TaYUC10 correlates with auxin and starch content of developing wheat grains

Author(s):  
Muhammed Rezwan Kabir ◽  
Heather M. Nonhebel ◽  
David Backhouse ◽  
Gal Winter

AbstractThe role of auxin in developing grains of wheat (Triticum aestivum) is contentious with contradictory reports indicating either positive or negative effects of IAA (indole-3-acetic acid) on grain size. In addition, the contributions to the IAA pool from de novo synthesis via tryptophan, and from hydrolysis of IAA-glucose are unclear. Here we describe the first comprehensive study of tryptophan aminotransferase and indole-3-pyruvate mono-oxygenase expression during wheat grain development from 5 to 20 days after anthesis. A comparison of expression data with measurements of endogenous IAA via combined liquid chromatography-tandem mass spectrometry with heavy isotope labelled internal standards indicates that TaTAR2.3-1B, TaYUC9-A1, TaYUC9-B, TaYUC9-D1, TaYUC10-A and TaYUC10-D are primarily responsible for IAA production in developing grains. Furthermore, we show that IAA synthesis is controlled by genes expressed specifically in developing wheat grains as has already been reported in rice (Oryza sativa) and maize (Zea mays). Our results cast doubt on the proposed role of THOUSAND-GRAIN WEIGHT gene, TaTGW6, in promoting larger grain size via negative effects on grain IAA content. The work on TaTGW6 has overlooked the contribution of the dominant IAA biosynthesis pathway. Although IAA synthesis occurs primarily in the endosperm of wheat grains, we show that the TaYUC9-1 group is also strongly expressed in the embryo. Within the endosperm, TaYUC9-1 expression is highest in aleurone and transfer cells, supporting data from other cereals suggesting that IAA has a key role in differentiation of these tissues.

2018 ◽  
Vol 61 (2) ◽  
pp. M13-M25 ◽  
Author(s):  
G Schuler ◽  
Y Dezhkam ◽  
L Tenbusch ◽  
MC Klymiuk ◽  
B Zimmer ◽  
...  

Boars exhibit high concentrations of sulfonated estrogens (SE) mainly originating from the testicular-epididymal compartment. Intriguingly, in porcine Leydig cells, sulfonation of estrogens is colocalized with aromatase and steroid sulfatase (STS), indicating that de novo synthesis of unconjugated estrogens (UE), their sulfonation and hydrolysis of SE occur within the same cell type. So far in boars no plausible concept concerning the role of SE has been put forward. To obtain new information on SE formation and hydrolysis, the porcine testicular-epididymal compartment was screened for the expression of the estrogen-specific sulfotransferase SULT1E1 and STS applying real-time RT-qPCR, Western blot and immunohistochemistry. The epididymal head was identified as the major site of SULT1E1 expression, whereas in the testis, it was virtually undetectable. However, SE tissue concentrations are clearly consistent with the testis as the predominant site of estrogen sulfonation. Results from measurements of estrogen sulfotransferase activity indicate that in the epididymis, SULT1E1 is the relevant enzyme, whereas in the testis, estrogens are sulfonated by a different sulfotransferase with a considerably lower affinity. STS expression and activity was high in the testis (Leydig cells, rete testis epithelium) but also present throughout the epididymis. In the epididymis, SULT1E1 and STS were colocalized in the ductal epithelium, and there was evidence for their apocrine secretion into the ductal lumen. The results suggest that in porcine Leydig cells, SE may be produced as a reservoir to support the levels of bioactive UE via the sulfatase pathway during periods of low activity of the pulsatile testicular steroidogenesis.


2004 ◽  
Vol 380 (3) ◽  
pp. 715-722 ◽  
Author(s):  
Kou-Yi TSERNG ◽  
Ronda L. GRIFFIN

Ceramides, which are produced from the hydrolysis of sphingomyelin or synthesized from serine and palmitate in a de novo pathway, are regarded as important cellular signals for inducing apoptosis. However, controversy over this proposed role of ceramides exists. Using stable isotope labelling coupled with GC (gas chromatography)-MS and mass isotopomer distribution analysis, we have studied the metabolism of exogenous long-chain ceramides in HL60 cells. Our results do not support the concept of enhanced ceramide transport into cells induced by solvent mixtures of ethanol and hydrocarbons. In addition, cell toxicity does not correlate with the amount of intact ceramide in the cells. Our results are more consistent with a disturbance of sphingomyelin metabolism induced by the solvent mixture. The characteristics of this disturbed sphingolipid disposition are the inhibition of dihydroceramide desaturation and an enhanced degradation of sphingomyelin. As a consequence, dihydroceramides accumulate and the cellular sphingomyelin content decreases. Inhibition of these pathways is most likely to be induced by the increased production of novel ceramide metabolites instead of by intact ceramides. Octadecane-1,2-diol is identified as a possible mediator. Treatments that divert ceramide degradation to the novel pathway are potential strategies in cancer therapy for inducing cell toxicity.


2021 ◽  
Vol 8 ◽  
Author(s):  
Shu Yu ◽  
Li Tian

The dietary needs of humans for provitamin A carotenoids arise from their inability to synthesize vitamin A de novo. To improve the status of this essential micronutrient, special attention has been given to biofortification of staple foods, such as wheat grains, which are consumed in large quantities but contain low levels of provitamin A carotenoids. However, there remains an unclear contribution of metabolic genes and homoeologs to the turnover of carotenoids in wheat grains. To better understand carotenoid catabolism in tetraploid wheat, Targeting Induced Local Lesions in Genomes (TILLING) mutants of CCD4, encoding a Carotenoid Cleavage Dioxygenase (CCD) that cleaves carotenoids into smaller apocarotenoid molecules, were isolated and characterized. Our analysis showed that ccd4 mutations co-segregated with Poltergeist-like (pll) mutations in the TILLING mutants of A and B subgenomes, hence the ccd-A4 pll-A, ccd-B4 pll-B, and ccd-A4 ccd-B4 pll-A pll-B mutants were analyzed in this study. Carotenoid profiles are comparable in mature grains of the mutant and control plants, indicating that CCD4 homoeologs do not have a major impact on carotenoid accumulation in grains. However, the neoxanthin content was increased in leaves of ccd-A4 ccd-B4 pll-A pll-B relative to the control. In addition, four unidentified carotenoids showed a unique presence in leaves of ccd-A4 ccd-B4 pll-A pll-B plants. These results suggested that CCD4 homoeologs may contribute to the turnover of neoxanthin and the unidentified carotenoids in leaves. Interestingly, abnormal spike, grain, and seminal root phenotypes were also observed for ccd-A4 pll-A, ccd-B4 pll-B, and ccd-A4 ccd-B4 pll-A pll-B plants, suggesting that CCD4 and/or PLL homoeologs could function toward these traits. Overall, this study not only reveals the role of CCD4 in cleavage of carotenoids in leaves and grains, but also uncovers several critical growth traits that are controlled by CCD4, PLL, or the CCD4-PLL interaction.


2016 ◽  
Vol 04 (01) ◽  
pp. 4-10

AbstractImmunosuppression permits graft survival after transplantation and consequently a longer and better life. On the other hand, it increases the risk of infection, for instance with cytomegalovirus (CMV). However, the various available immunosuppressive therapies differ in this regard. One of the first clinical trials using de novo everolimus after kidney transplantation [1] already revealed a considerably lower incidence of CMV infection in the everolimus arms than in the mycophenolate mofetil (MMF) arm. This result was repeatedly confirmed in later studies [2–4]. Everolimus is now considered a substance with antiviral properties. This article is based on the expert meeting “Posttransplant CMV infection and the role of immunosuppression”. The expert panel called for a paradigm shift: In a CMV prevention strategy the targeted selection of the immunosuppressive therapy is also a key element. For patients with elevated risk of CMV, mTOR inhibitor-based immunosuppression is advantageous as it is associated with a significantly lower incidence of CMV events.


2020 ◽  
pp. 92-107 ◽  
Author(s):  
A. I. Bakhtigaraeva ◽  
A. A. Stavinskaya

The article considers the role of trust in the economy, the mechanisms of its accumulation and the possibility of using it as one of the growth factors in the future. The advantages and disadvantages of measuring the level of generalized trust using two alternative questions — about trusting people in general and trusting strangers — are analyzed. The results of the analysis of dynamics of the level of generalized trust among Russian youth, obtained within the study of the Institute for National Projects in 10 regions of Russia, are presented. It is shown that there are no significant changes in trust in people in general during the study at university. At the same time, the level of trust in strangers falls, which can negatively affect the level of trust in the country as a whole, and as a result have negative effects on the development of the economy in the future. Possible causes of the observed trends and the role of universities are discussed. Also the question about the connection between the level of education and generalized trust in countries with different quality of the institutional environment is raised.


2015 ◽  
Vol 94 (2) ◽  
pp. 207-236 ◽  
Author(s):  
Catriona M. M. Macdonald

The career and posthumous reputation of Andrew Lang (1844–1912) call into question Scottish historiographical conventions of the era following the death of Sir Walter Scott which foreground the apparent triumph of scientific methods over Romance and the professionalisation of the discipline within a university setting. Taking issue with the premise of notions relating to the Strange Death of Scottish History in the mid-nineteenth century, it is proposed that perceptions of Scottish historiographical exceptionalism in a European context and presumptions of Scottish inferiorism stand in need of re-assessment. By offering alternative readings of the reformation, by uncoupling unionism from whiggism, by reaffirming the role of Romance in ‘serious’ Scottish history, and by disrupting distinctions between whig and Jacobite, the historical works and the surviving personal papers of Andrew Lang cast doubt on many conventional grand narratives and the paradigms conventionally used to make sense of Scottish historiography.


Author(s):  
باي زكوب عبد العالي ◽  
سوهيرين محمد صوليحين

الملخّصيعدّ عبد الحميد بن باديس أحد العلماء الجزائريين المبرزين بالإصلاح الاجتماعي والدّيني والسّياسي والتربوي، عاش خمسين سنة في القرن العشرين الميلادي، حيث كانت ولادته سنة 1889م، وكانت وفاته سنة 1940م، ولقد فرض الواقع الجزائري إبّان فترة الاحتلال الفرنسي الذي كان يسعى إلى طمس ثوابت الأمّة الجزائرية، وخرق تاريخها، وهُويّتها، وثقافتها، ووحدتها الدينيّة، واللّغوية على ابن باديس أن يسلك نهج التربية والتعليم، قاصداً بذلك مواجهة الاحتلال الفرنسي الغاشم من خلال عدّة جبهات ومجالات كمثل مجال الصحافة، ومجال التربية والتعليم، ومجال الجمعيات، ومجال السياسة وغير ذلك، يهدف هذا البحث إلى إبراز دور عبد الحميد بن باديس في النّهوض بالأمّة الجزائريّة نحو تربيّة أفضل، وحياة أسعد، فيبدأ أوّلاً وبشكل موجز، بالتعرّف على الفترة الصعبة التي عايشها ابن باديس والمتمثلة في فترة الاحتلال الفرنسي الغاشم، وآثاره السلبية على الصعيد السياسي والاقتصادي والاجتماعي والثقافي والديني الجزائري وقتذاك، ثم يقوم ثانياً بتسليط الضّوء على حياة ابن باديس وتكوينه العلمي ورحلاته الداخلية وأسفاره الخارجية؛ ثم يسعى ثالثاً وبتعمّق، التعرّف على أعمال ابن باديس الاجتماعيّة وجهوده التربويّة التي أخذت حظّاً وافراً من حياته اليومية، والتي تركّزت على منبرين رئيسين، هما: منبر الصّحافة، ومنبر التربيّة والتعليم.الكلمات المفتاحيّة: الإمام عبد الحميد بن باديس، الاحتلال الفرنسي، التربية، الجزائر، الإصلاح.             AbstractImÉm ‘Abd al-×amÊd ibn BÉdÊs is an Algerian scientist, and eminent social, religious, political and educational reformer. He lived fifty years in the twentieth century. He was born in 1889 and died in 1940, and lived during the French occupation that attempted to distort and undermine the foundations of the Algerian nation by destroying its history, identity, culture, and religious and linguistic unity. Ibn BÉdÊs pursued an educational approach to face the brutal French occupation on several fronts, including journalism, education, civil associations, politics, etc. This paper highlights the role of ‘Abd al-×amÊd ibn BÉdÊs in the advancement of the Algerian nation toward better education and a happier life. The paper begins with a brief canvas of the difficult times in which Ibn BÉdÊs lived, and the negative effects of the brutal French occupation from political, economic, social, cultural and religious angles, besides highlighting the life of Ibn BÉdÊs, his education and his local and international travels. The focus of this research is an in-depth examination of Ibn BÉdÊs’ social and educational efforts that consumed much of his daily routine: journalism, and education.Keywords: ImÉm ‘Abd al-×amÊd ibn BÉdÊs, the French Occupation, Education, Algeria, Reform.


2004 ◽  
Vol 52 (Suppl 1) ◽  
pp. S122.6-S123
Author(s):  
M. Garg ◽  
C. Bell ◽  
L. Rogers ◽  
S. Bassilian ◽  
W. N.P. Lee

2021 ◽  
pp. 216747952199237
Author(s):  
Ondřej Trunečka

This study explores how professional athletes perceive sports journalists and the role of the media. They acknowledge that communication with journalists is an essential part of their profession and appreciate the verified information, knowledge, and dutiful preparation. They consider the main role of media as monitorial. In some cases, they cast doubt on journalists’ ability to evaluate athletic performance accurately, and they are also critical of errors in interviews, however they acknowledgethat there are good, and possibly excellent journalists as well.


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