Project description:To identify the molecular pathways that are perturbed due to transient zinc chelation Zinc is known to regulate the functions of about 10% of the human proteome and a large number of physiological processes that are zinc dependent have been identified and characterized under conditions of zinc deficiency and supplementation. As zinc homeostasis is closely linked to the normal functioning of both prokaryotic and eukaryotic cells, many pathogens are directly or indirectly affected by perturbations in zinc homeostasis. Dengue virus (DENV), a mosquito-borne, positive-strand RNA virus from the family Flaviviridae, has emerged as one of the major public health concerns in India and recent estimates suggest that over 60 million people globally get infected with DENV every year. The crystal structures of NS5 protein of DENV and West Nile virus have identified zinc binding site in RdRp domain and propose an important structural role for zinc ions in polymerase activity. Therefore, we investigated whether perturbation in intracellular zinc pools influence dengue infection. We utilized N,N,N’,N’-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN), a zinc-specific chelator, to mimic zinc-deficiency in cell culture models of infection and investigated the effect of zinc depletion on DENV life-cycle.
Project description:How cells safeguard essential zinc-dependent functions during zinc deficiency is poorly understood. A long-debated strategy is whether soluble metal-trafficking chaperones exist to prioritize specific zinc-dependent proteins. We identified a eukaryotic family of metallochaperones that physically interacts with zinc-dependent methionine aminopeptidase type I (MAP1) in human and yeast. Deletion of the yeast metallochaperone-encoding gene NMC1 (formerly YNR029c) leads to a zinc-deficiency growth defect and defective initiator methionine cleavage caused by loss of Map1p activity. To better understand the observed fitness defects due to the lack of NMC1 under zinc deficiency, we used proteomics with Tandem Mass Tag (TMT) quantitation derived from WT, nmc1Delta, and map2Delta nmc1Delta strains grown in zinc-limited (1 uM) or zinc-replete (100 uM) conditions. Proteomics reveal global impacts due to the loss of NMC1 and Map1p function, including mis-regulation of the Zap1p regulon, and suggests that Nmc1p is required to avoid a compounding effect of Map1p dysfunction on cell survival during zinc deficiency.
Project description:Zinc is an essential trace element that is closely related to learning and memory ability. The hippocampus plays an important role in learning and memory and has the highest zinc concentration in the brain. Severe zinc deficiency (zinc-deprived diet) significantly alter hippocampal protein expression and impair learning and memory abilities. However, no study has investigated the effects of marginal zinc deficiency (low zinc diet) on hippocampal proteins and learning and memory abilities. In this study, the rat model after 4 and 8 weeks of feeding with low zinc diet was first used to identify and quantify the hippocampal proteins of low zinc rats by high-thoughput proteomics technology. Explore the changes of hippocampus proteome patterns after 4 and 8 weeks of feeding with low zinc diet were compared with those in control rats.
Project description:Phase II randomized trial to investigate whether supplementation of zinc decreases the incidence of HFSR that occurs after treatment of tyrosine kinase inhibitor, regorafenib.