ZnT8 Loss of Function Mutation Increases Resistance of Human Embryonic Stem Cell-Derived Beta Cells to Apoptosis in Low Zinc Condition
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA701465 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The rare SLC30A8 mutation encoding a truncating p.Arg138* variant (R138X) in zinc transporter 8 (ZnT8) is associated with a 65% reduced risk for type 2 diabetes. To determine whether ZnT8 is required for beta cell development and function, we derived human pluripotent stem cells carrying the R138X mutation and differentiated them into insulin-producing cells. We found that human pluripotent stem cells with homozygous or heterozygous R138X mutation and the null (KO) mutation have normal efficiency of differentiation towards insulin-producing cells, but these cells show diffuse granules that lack crystalline zinc-containing insulin granules. Insulin secretion is not compromised in vitro by KO or R138X mutations in human embryonic stem cell-derived beta cells (sc-beta cells). Likewise, the ability of sc-beta cells to secrete insulin and maintain glucose homeostasis after transplantation into mice was comparable across different genotypes. Interestingly, sc-beta cells with the ZnT8 KO mutation showed increased cytoplasmic zinc, and cells with either KO or R138X mutation were resistant to apoptosis when extracellular zinc was limiting. These findings are consistent with a protective role of zinc in cell death and with the protective role of zinc in T2D.
2022-02-11 | GSE166641 | GEO
Project description:The rare SLC30A8 mutation encoding a truncating p.Arg138* variant (R138X) in zinc transporter 8 (ZnT8) is associated with a 65% reduced risk for type 2 diabetes. To determine whether ZnT8 is required for beta cell development and function, we derived human pluripotent stem cells carrying the R138X mutation and differentiated them into insulin-producing cells. We found that human pluripotent stem cells with homozygous or heterozygous R138X mutation and the null (KO) mutation have normal efficiency of differentiation towards insulin-producing cells, but these cells show diffuse granules that lack crystalline zinc-containing insulin granules. Insulin secretion is not compromised in vitro by KO or R138X mutations in human embryonic stem cell-derived beta cells (sc-beta cells). Likewise, the ability of sc-beta cells to secrete insulin and maintain glucose homeostasis after transplantation into mice was comparable across different genotypes. Interestingly, sc-beta cells with the SLC30A8 KO mutation showed increased cytoplasmic zinc, and cells with either KO or R138X mutation were resistant to apoptosis when extracellular zinc was limiting. These findings are consistent with a protective role of zinc in cell death and with the protective role of zinc in T2D.
| S-EPMC10047077 | biostudies-literature
Project description:Transcription profile of low zinc growth condition in zinc regulatory null mutant
2008-02-22 | E-TABM-427 | biostudies-arrayexpress
Project description:There is an emerging appreciation of the importance of zinc in regulating cancer cell growth and proliferation. Recently, we showed that the anticancer agent motexafin gadolinium (MGd) disrupted zinc metabolism in A549 lung cancer cells, leading, in the presence of exogenous zinc, to cell death. Here, we report the effect of MGd and exogenous zinc on intracellular levels of free zinc, oxidative stress, proliferation, and cell death in exponential phase human B-cell lymphoma and other hematologic cell lines. We find that increased levels of oxidative stress and intracellular free zinc precede and correlate with cell cycle arrest and apoptosis. To better understand the molecular basis of these cellular responses, gene expression profiling analyses were conducted on Ramos cell cultures treated with MGd and/or zinc acetate. Cultures treated with MGd or zinc acetate alone elicited transcriptional responses characterized by induction of metal response element-binding transcription factor-1 (MTF-1)-regulated and hypoxia-inducible transcription factor-1 (HIF-1)-regulated genes. Cultures cotreated with MGd and zinc acetate displayed further increases in the levels of MTF-1- and HIF-1-regulated transcripts as well as additional transcripts regulated by NF-E2-related transcription factor 2. These data provide insights into the molecular changes that accompany the disruption of intracellular zinc homeostasis and support a role for MGd in treatment of B-cell hematologic malignancies.
2007-10-02 | E-GEOD-2964 | biostudies-arrayexpress
Project description:We report the effect of motexafin gadolinium (MGd) and exogenous zinc on intracellular levels of free zinc, oxidative stress, proliferation, cell cycle, and cell death in exponential phase human B-cell lymphoma and other hematologic cell lines. We find that increased levels of oxidative stress and intracellular free zinc precede and correlate with cell cycle arrest and apoptotic response. Treatment with exogenous zinc increased oxidative stress and, conversely, oxidative stress resulted in increased intracellular free zinc levels. To better understand the molecular basis of these results, gene expression profiling analyses were conducted on Ramos cell cultures treated with MGd and/or zinc acetate. Cultures treated with MGd or zinc acetate alone elicited transcriptional responses characterized by induction of MTF-1 and HIF-1 regulated genes. Cultures co-treated with MGd and zinc acetate displayed further increases in the levels of MTF-1 and HIF-1 regulated transcripts as well as additional transcripts regulated by NRF-2. Overall, these studies suggest that co-treatment of Ramos cells with MGd and zinc acetate increase intracellular zinc levels with a concomitant rise in oxidative stress levels that activate adaptive survival responses but eventually lead to cell death. Keywords: Dose response
2006-01-01 | GSE2964 | GEO
Project description:Fungal diseases significantly impact human mortality and morbidity. However, despite the number of annual deaths caused by fungi exceeding 1.6 million, these microorganisms are often neglected. Fonsecaea pedrosoi is the main etiologic agent of chromoblastomycosis (CBM), a chronic mycosis that affects the skin and subcutaneous tissue that, in 2017, was included in the WHO list of neglected tropical diseases. It is essentially an occupational disease that affects individuals in poverty, causing significant morbidity and mortality. CBM is a disease of global distribution, and most cases are described in tropical and subtropical regions of America, Africa and Asia. Despite its importance in the etiology of the disease, the molecular mechanisms involved in the interaction of F. pedrosoi with the host are still poorly explored. During the infectious process, the host limits the availability of zinc to fungal pathogens in order to contain the infection, a process called nutritional immunity. In this work, we show that F. pedrosoi is able to grow in a wide range of zinc concentration and that genes related to zinc uptake are induced in zinc-limiting conditions. Proteomic analysis revealed that after 48 h of exposure to zinc scarcity synthesis of fatty acid and the pentose-phosphate pathway are up-regulated. On the other hand, protein synthesis is repressed. Additionally, glucan increases while chitin content is reduced in the cell wall under zinc limitation, demonstrating that cell wall remodeling is important for adaptation to this stress condition.
2024-01-29 | PXD048714 | Pride
Project description:Zinc increases hormone receptor expression in human ovarian granulosa cells and gene profiling
| PRJNA830455 | ENA
Project description:Only a small number of genes are known direct targets of the zinc-responsive transcription factor MTF1; therefore, the aim of this study was to gain a more complete understanding of the MTF-1 regulated zinc-responsive component of the transcriptome. A targeted siRNA was used to deplete MTF1 expression in the human intestinal cell line Caco-2. We predicted that the response to zinc of direct MTF1 target genes would be abrogated by MTF1 knockdown. Surprisingly, a greater number of genes were regulated by zinc following MFT1 knockdown, and most genes that responded to zinc under both control and MTF1-depleted conditions had an augmented response in the latter condition. Exceptions were the zinc effluxer ZnT1 and a suite of metallothionein genes, suggesting that responses of other genes to zinc are usually buffered by increases in these proteins. We propose that MTF1 heads a hierarchy of zinc sensors, and through controlling the expression of a raft of metallothioneins and other key proteins involved in controlling intracellular zinc levels (e.g. ZnT1) alters zinc buffering capacity and total cellular zinc content. We tested and validated this model by overexpressing metallothionein and observing the predicted curtailment in response of the zinc-repressed SLC30A5 (ZnT5) promoter. The model provides the framework for an integrated understanding of cellular zinc homeostasis. Because MTs can bind metals other than zinc, this framework links with overall cellular metal homeostasis. Gene expression profiling by Illumina BeadArray of the effects of ZNF658 gene knockdown by siRNA. 2 different siRNAs were used, with appropriate non-targetting controls. All experiments were carried out in triplicate.
2016-02-24 | E-GEOD-76510 | biostudies-arrayexpress
Project description:Only a small number of genes are known direct targets of the zinc-responsive transcription factor MTF1; therefore, the aim of this study was to gain a more complete understanding of the MTF-1 regulated zinc-responsive component of the transcriptome. A targeted siRNA was used to deplete MTF1 expression in the human intestinal cell line Caco-2. We predicted that the response to zinc of direct MTF1 target genes would be abrogated by MTF1 knockdown. Surprisingly, a greater number of genes were regulated by zinc following MFT1 knockdown, and most genes that responded to zinc under both control and MTF1-depleted conditions had an augmented response in the latter condition. Exceptions were the zinc effluxer ZnT1 and a suite of metallothionein genes, suggesting that responses of other genes to zinc are usually buffered by increases in these proteins. We propose that MTF1 heads a hierarchy of zinc sensors, and through controlling the expression of a raft of metallothioneins and other key proteins involved in controlling intracellular zinc levels (e.g. ZnT1) alters zinc buffering capacity and total cellular zinc content. We tested and validated this model by overexpressing metallothionein and observing the predicted curtailment in response of the zinc-repressed SLC30A5 (ZnT5) promoter. The model provides the framework for an integrated understanding of cellular zinc homeostasis. Because MTs can bind metals other than zinc, this framework links with overall cellular metal homeostasis.
2016-02-24 | GSE76510 | GEO
Project description:Old Human Serum Increases Apoptosis and Molecular Ageing Markers In Human Hippocampal Progenitor Cells
| PRJNA416774 | ENA