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The objective of this study was to investigate the alterations in physiological, biochemical, and transcriptional reactions in the flag leaf of rice following the application of Trichoderma as a biofertilizer (BF) at both ambient (aCO2; 395 ppm) and enhanced (eCO2; 550 ppm) carbon dioxide levels. A comparatively smaller percentage change was observed in the photosynthetic parameters, including photosynthetic rate, respiration, and stomatal conductance, subsequent to the introduction of BF in the elevated carbon dioxide (eCO2) environment. Furthermore, biochemical analysis revealed a noteworthy elevation in photosynthetic pigments, total sugar, proline, and ascorbate peroxidase concentration levels in plants treated with BF under ambient and increased carbon dioxide conditions. The buildup of indole‐3‐acetic acid (IAA) was shown to be increased in rice treated with BF under both conditions. Moreover, ICP‐MS analysis demonstrated an augmentation in the levels of vital micronutrients in the experimental group while observing no alterations in the carbon‐to‐nitrogen ratio within the flag leaf. The examination of transcriptional responses in the flag leaf demonstrated an increase in the expression of genes associated with the photosynthetic system, amino acid metabolism, several transporters, including aquaporin, and the phosphate pathway, as well as carbon and nitrogen metabolism. Hence, our work elucidates the effective role of Trichoderma in mitigating the adverse consequences associated with elevated levels of atmospheric carbon dioxide (eCO2). [ABSTRACT FROM AUTHOR]

Glycosphingolipids and glycerophospholipids bind CD1d. Glycosphingolipid‐reactive invariant NKT‐cells (iNKT) exhibit myriad immune effects, however, little is known about the functions of phospholipid‐reactive T cells (PLT). We report that the normal mouse immune repertoire contains αβ T cells, which recognize self‐glycerophospholipids such as phosphatidic acid (PA) in a CD1d‐restricted manner and don't cross‐react with iNKT‐cell ligands. PA bound to CD1d in the absence of lipid transfer proteins. Upon in vivo priming, PA induced an expansion and activation of T cells in Ag‐specific manner. Crystal structure of the CD1d:PA complex revealed that the ligand is centrally located in the CD1d‐binding groove opening for TCR recognition. Moreover, the increased flexibility of the two acyl chains in diacylglycerol ligands and a less stringent‐binding orientation for glycerophospholipids as compared with the bindings of glycosphingolipids may allow glycerophospholipids to readily occupy CD1d. Indeed, PA competed with α‐galactosylceramide to load onto CD1d, leading to reduced expression of CD1d:α‐galactosylceramide complexes on the surface of dendritic cells. Consistently, glycerophospholipids reduced iNKT‐cell proliferation, expansion, and cytokine production in vitro and in vivo. Such superior ability of self‐glycerophospholipids to compete with iNKT‐cell ligands to occupy CD1d may help maintain homeostasis between the diverse subsets of lipid‐reactive T cells, with important pathogenetic and therapeutic implications. Glycerophospholipids (GPL), such as phosphatidic acid, bind the lipid antigen presenting molecule CD1d and activate phospholipid‐reactive T cells (PLT). Due to their less stringent binding orientation in the CD1d groove, GPLs compete with self and exogenously administered glycerosphingolipids (GSLs) to load onto CD1d, thus inhibiting the activation of iNKT cells. [ABSTRACT FROM AUTHOR]

Drought is a major adverse environmental factor that limits plant productivity. Concomitant assimilation of carbon (C) and nitrogen (N) in illuminated leaves requires the regulated partitioning of reductant and photosynthate to sustain the demands of amino acid and carbohydrate biosynthesis. The short-term exposure to drought and its responses of photosynthesis and photosynthate partitioning to N enrichment was studied in Cyamopsis tetragonoloba (L.) Taub (guar). Four contrasting varieties of guar, HG-563, RGC-986 (drought-tolerant) and RGC-471, Varsha (drought-sensitive) were subjected to 15 days water stress and leaf tissues were studied in order to contemplate the counter strategy engaged under drought conditions. In guar plants, sensors trigger a signalling cascade that activates numerous proteins to induce the expression of certain genes involved in carbon and nitrogen metabolism.The levels of glucose, starch, and Glutamate dehydrogenase (GDH), Aspartate aminotransferase (AspAT), isocitrate dehydrogenase (ICDH), Nitrate Reductase (NR), and Nitrite reductase (NiR) activities were determined biochemically during 15 days drought treatment, at three stages. Further, the carbon (oxidative phosphorylation and TCA cycle) - nitrogen metabolic pathway interaction was studied at the molecular level. The respiratory pathway genes were upregulated, while the nitrogen metabolic pathway genes were downregulated under all stages of drought in guar plants. The physiological, biochemical and molecular data suggests that the high rates of dark respiration was insufficient to provide extra carbon required to assist amino acid synthesis but rather sufficed by a rapid metamorphosis in the photosynthetic carbon partitioning to amino acid metabolism via the nitrogen metabolism. [Display omitted] • Drought causes NADH DEHYDROGENASE gene to escalate dark respiration. • Nitrogen assimilation reduces under drought in leguminous Cyamopsis tetragonoloba. • Drought triggers protein kinase cascade signalling in guar plants. • Drought regulates nitrogen metabolic genes in guar. • Drought triggers increase in sugar content at the cost of amino acids. [ABSTRACT FROM AUTHOR]

Plants adapt to changing environmental conditions by adjusting their growth physiology. Nitrate (NO3-) and ammonium (NH4+) are the major inorganic nitrogen forms for plant uptake. However, high NH4+ inhibits plant growth, and roots undergo striking changes, such as inhibition of cell expansion and division, leading to reduced root elongation. In this work, we show that high NH4+ modulates nitrogen metabolism and root developmental physiology by inhibiting iron (Fe)-dependent Jasmonate (JA) signaling and response in Arabidopsis (Arabidopsis thaliana). Transcriptomic data suggested that NH4+ availability regulates Fe and JA-responsive genes. High NH4+ levels led to enhanced root Fe accumulation, which impaired nitrogen balance and growth by suppressing JA biosynthesis and signaling response. Integrating pharmacological, physiological, and genetic experiments revealed the involvement of NH4+ and Fe-derived responses in regulating root growth and nitrogen metabolism through modulation of the JA pathway during NH4+ stress. The JA signaling transcription factor MYC2 directly bound the promoter of the NITRATE TRANSPORTER 1.1 (NRT1.1) and repressed it to optimize the NH4+/Fe-JA balance for plant adaptation during NH4+ stress. Our findings illustrate the intricate balance between nutrient and hormone-derived signaling pathways that appear essential for optimizing plant growth by adjusting physiological and metabolic responses during NH4+/Fe stress., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

There is a paucity of data on the sterility of peritoneal dialysis fluid (PDF) after drug admixture. International Society for Peritoneal Dialysis (ISPD) guidelines suggest using sterile technique when admixing antibiotics; however, the degree of sterility remains unclear. This issue is most pertinent when preparing take-home PDF for outpatient treatment of peritonitis. This study compares the sterility of PDF admixed with antibiotics using a non-touch aseptic technique (NTAT) versus sterile technique.Groups of 8 PDF mixtures (1.5% Dianeal or Icodextrin [Baxter International Inc., Spring Grove, IL, USA]) were admixed with 1 g/L ceftazidime and vancomycin, or 20 mL saline, either by a pharmacist using sterile technique in a sterile suite, or a nurse in a clinical room using NTAT. Dianeal inoculated with 1 × 10 6 colony-forming units (CFU)/L of coagulase-negative Staphylococcus (CNS), with and without antibiotics, served as positive controls. Admixed PDFs were left at room temperature for 72 hours, then cultured using the BacT/ALERT system. A positive culture by day 5 constituted a contamination. Differences in proportion of contamination between groups were assessed using the Chi-squared test.Eighty PDF bags underwent microbiological testing. Sterility was maintained in all bags, independent of technique (NTAT versus sterile technique), type of PDF (Dianeal versus Icodextrin), or whether antibiotics were admixed. Of the positive controls, CNS-inoculated PDFs without antibiotics were all culture positive; however, when inoculated into antibiotic-admixed PDFs, only S. haemolyticus remained culture-positive ( p < 0.0001).In conclusion, PDF sterility can be maintained using NTAT for up to 3 days at room temperature. Currently, there is insufficient evidence to adopt sterile technique in sterile suites when admixing take-home PDF., (Copyright © 2018 International Society for Peritoneal Dialysis.)