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Worldwide, 50% of soil is acidic, which induces aluminium (Al) toxicity in plants, as the phyto-availability of Al 3+ increases in acidic soil. Plants responds to Al 3+ toxicity by exuding organic acids into the rhizosphere. The organic acid responsible for Al 3+ stress response varies from species to species, which in the case of blackgram (Vigna mungo L.) is citrate. In blackgram, an Arabidopsis malate transporter, AtALMT1, was overexpressed with the motive of inducing enhanced exudation of malate. Transgenics were generated using cotyledon node explants through Agrobacterium tumefaciens-mediated transformation. The putative transgenics were initially screened by AtALMT1-specific genomic DNA PCR, followed by quantitative PCR. Two independent transgenic events were identified and functionally characterized in the T 3 generation. The transgenic lines, Line 1 and 2, showed better root growth, relative water content and chlorophyll content under Al 3+ stress. Both lines also accounted for less oxidative damage, due to reduced accumulation of ROS molecules. Photosynthetic efficiency, as measured in terms of F v /F m , NPQ and Y(II), increased when compared to the wild type (WT). Relative expression of genes (VmSTOP1, VmALS3, VmMATE) responsible for Al 3+ stress response in blackgram showed that overexpression of a malate transporter did not have any effect on their expression. Malate exudation increased whereas citrate exudation did not show any divergence from the WT. A pot stress assay found that the transgenics showed better adaptation to acidic soil. This report demonstrates that the overexpression of a malate transporter in a non-malate exuding species improves adaptation to Al 3+ toxicity in acidic soil without effecting its stress response mechanism., (© 2020 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.)

Cellular hyporesponsiveness observed during helminth infections is attributed to factors such as antigen-presenting cells (APC) dysfunction, increased interleukin-10(IL-10), regulatory T cells and induction of CD4 + T (Th)-cell apoptosis. Increased Fas ligand (FasL) expression on the surface of B-1 cells and induction of apoptosis of Th cells by FasL-expressing B-1 cells due to helminth infection were demonstrated in murine model of helminth infection where as profile of FasL expression, Th-cell apoptosis and correlation between these two populations of cells in clinical filariasis remain unknown. In this study, we have scored the profile of apoptotic Th-cell population and FasL-expressing B-1 cells in different clinical categories of filariasis. The peripheral apoptotic T-helper cells were significantly increased in filarial patients compared to endemic controls. Expression of FasL on the surface of peripheral B-1 cells increased in filarial patients and positively correlated with peripheral apoptotic T-helper cells indicating FasL-expressing B-1 cells may be one of the important mediators of Th-cell apoptosis and immune anergy during filarial pathology., (© 2017 John Wiley & Sons Ltd.)