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Thakur, G.

Publications and source records attributed to Thakur, G..

3 recordsLinked to original sources

Computational predictions and evolutionary analysis of LrK10 kinase-related putative PSTOL1 gene homeologs in wheat and orthologs of its wild relatives.

Phosphorus Starvation Tolerance 1 in rice (OsPSTOL1, known as Phosphorus uptake 1, Pup1) is a receptor-like cytoplasmic protein kinase that confers tolerance to phosphorus deficiency. The OsPSTOL1 gene possesses a Ser/Thr kinase and shows high amino-acid sequence similarity with the leaf rust receptor-like kinase (OsLrK10). We hypothesize that the putative wheat TaPSTOL1 and TaLrK10 have a common ancestral origin and that putative TaPSTOL1 diverged recently acquiring new structural modifications and biological functions in the process. In this study, we identified all putative TaPSTOL1 homeologs and examine the evolutionary relationship between TaPSTOL1 and TaLrK10 in Triticum species. Our results indicate that the putative TaPSTOL1 diverged recently without possessing the amino-terminal domain, which is a typical characteristic of TaLrK10. We observed numerous conversions tracts between these two genes and the substitution pattern of randomly selected amino acids indicates that dynamic selection pressures acted on both genes. The putative TaPSTOL1 shows high nucleotide diversity compared to TaLrK10 within Triticum species. Further, a multiple-sequence analysis reveals that the third exon of TaLrK10 appears to have been duplicated and diverged as a putative single-exon based TaPSTOL1 in bread wheat. Overall, our comparative analysis indicates that both TaPSTOL1 and TaLrK10 appears to have diverged from a common ancestor, acquiring distinct structural organizations and biological functions.

genomics↗

Novel neutrophil subsets associated with sepsis, vascular dysfunction and metabolic alterations identified using systems immunology

Sepsis is a life-threatening condition caused by a dysregulated host response to infection. Despite continued efforts to understand the pathophysiology of sepsis, no effective therapies are currently available. While singular components of the aberrant immune response have been investigated, comprehensive studies linking different data layers are lacking. Using an integrated systems immunology approach, we evaluated neutrophil phenotypes and concomitant changes in cytokines and metabolites in sepsis patients. Our findings identify novel differentially expressed immature neutrophil subsets in sepsis patients. These and other subsets correlate with various proteins, metabolites, and lipids, including pentraxin-3, angiopoietin-2 and lysophosphatidylcholines, in sepsis patients. These results enabled the construction of a predictive model based on weighted multi-omics linear regression analysis for patient classification. These findings could help inform earlier patient stratification and treatment options, as well as facilitate future mechanistic studies targeting the trifecta of surface marker expression, cytokines, and metabolites.

immunology↗

Nutrient signaling pathways regulate amyloid clearance and synaptic loss in Alzheimer's disease

Extra-cellular accumulation of Amyloid-{beta} (A{beta}) plaques is causatively associated with Alzheimers disease (AD). However, mechanisms that mediate the pre-pathological state of amyloid plaque formation remain elusive. Here, using paired RNAi and kinase inhibitor screens, we discovered that AKT-mediated insulin/nutrient signaling suppresses lysosomal clearance of A{beta} and promotes amyloid formation. This mechanism is cell-autonomous and functions in multiple systems, including iPSC-derived human neurons and in vivo. Nutrient signaling regulates amyloid formation via distinct lysosomal functional mechanisms, while enhanced amino acid signaling promotes amyloid formation by transcriptionally suppressing lysosome biogenesis, and high intracellular cholesterol levels suppress lysosomal clearance of amyloid by increasing the number of non-functional lysosomes. The nutrient signaling pathway, present in both neurons and microglia, regulates lysosomal clearance of amyloid and microglia mediated synapse loss, both in vitro and in vivo. Clinically, older hyperlipidemic patients showed less synapse loss through microglia and performed better in cognitive tests. Thus, our results reveal a bi-partite cellular quality control system regulated by the insulinnutrient signaling that in neurons regulates A{beta} peptide clearance and in microglia regulates synaptic loss, both processes causally associated with AD. Our results also caution against reducing amyloid through such processes as this might also result in synapse loss.

neuroscience↗