Alkalinity modulates a unique suite of genes to recalibrate growth and pH homeostasis.

Alkaline soils pose a conglomerate of constraints to plants, restricting the growth and fitness of non-adapted species in habitats with low active proton concentrations. To thrive under such conditions, plants have to compensate for a potential increase in cytosolic pH and restricted softening of the cell wall to invigorate cell elongation in a proton-depleted environment. To discern mechanisms that aid in the adaptation to external pH, we grew plants on media with pH values ranging from 5.5 to 8.5. Growth was severely restricted above pH 6.5 and associated with decreasing chlorophyll levels at alkaline pH. Bicarbonate treatment worsened plant performance, suggesting effects that differ from those exerted by pH as such. Transcriptional profiling of roots subjected to short-term transfer from optimal (pH 5.5) to alkaline (pH 7.5) media unveiled a large set of differentially expressed genes that were partially congruent with genes affected by low pH, bicarbonate, and nitrate, but showed only a very small overlap with genes responsive to the availability of iron. Further analysis of selected genes disclosed pronounced responsiveness of their expression over a wide range of external pH values. Alkalinity altered the expression of various proton/anion co-transporters, possibly to recalibrate cellular proton homeostasis. Co-expression analysis of pH-responsive genes identified a module of genes encoding proteins with putative functions in the regulation of root growth, which appears to be conserved in plants subjected to low pH or bicarbonate. Our analysis provides an inventory of pH-sensitive genes and allows comprehensive insights into processes that are orchestrated by external pH.

Tandem Mass Tag-Based Phosphoproteomics in Plants.

Mass spectrometry-based proteomics provide a powerful tool for plant research, allowing global detection of steady-state levels of proteins under a given experimental setup. Here, we provide an optimized protocol for proteomic profiling using tandem mass tag (TMT) labeling followed by liquid chromatography-mass spectrometry (LC-MS/MS) to quantitate phosphopeptides and non-phosphopeptides from the same samples. The outlined protocol comprises a series of successive steps, namely, SDS (sodium dodecyl sulfate) protein extraction, protein precipitation, digestion, TMT labeling, phosphopeptide enrichment, high pH reversed-phase fractionation, LC-MS/MS analysis, protein identification, and data analysis. Our proteome-scale protocol requires 0.1 mg protein per sample and allows for the reliable and accurate quantification of more than 8000 proteins in Arabidopsis plant samples across multiple conditions, including low abundant peptides.

Adjunct yoga therapy: Influence on heart rate variability in major depressive disorder - A randomized controlled trial.

HRV is inversely proportional to severity of depression. Effect of 12-weeks adjunct yoga therapy on HRV in patients with MDD was assessed through a randomized controlled trial. Sixty-eight subjects (40 females) with mean age 31.58 ± 8.79 years, scoring ≥ 18 on HDRS were randomized to either (YG; n = 35) or (WG; n = 33). Linear mixed model analysis showed no significant difference between groups. On comparing change in mean percentage, substantial more decrease could be elicited only for LF/HF ratio in YG compared to WG, while being comparable for other variables across the groups. Findings suggest Yoga therapy may help in bringing parasympathetic dominance in patients with MDD.