Project description:Total RNA was purified from keratinocytes isolated from FFPE arsenic-induced skin lesion samples collected from individuals exposed to high concentrations of arsenic exceeding 50 ppb in drinking water in Murshidibad district of West Bengal, India.
Project description:Arsenic (As) is highly toxic element to all forms of life and is a major environmental contaminant. Understanding acquisition, detoxification, and adaptation mechanisms in bacteria that are associated with host in arsenic-rich conditions can provide novel insights into dynamics of host-microbe-microenvironment interactions. In the present study, we have investigated an arsenic resistance mechanism acquired during the evolution of a particular lineage in the population of Xanthomonas oryzae pv. oryzae (Xoo), which is a serious plant pathogen infecting rice. Our study revealed the horizontal acquisition of a novel chromosomal 12kb ars cassette in Xoo IXO1088 that confers high resistance to arsenate/arsenite. The ars cassette comprises several genes that constitute an operon induced in the presence of arsenate/arsenite. This cassette has spread in lineage with highly virulent strains owing to a particular lineage’s evolutionary success. Further, we performed the transcriptomic analysis of Xoo strain IXO1088 under arsenate/arsenite exposure using RNA sequencing. The transcriptomic analysis revealed that arsenic detoxification and efflux, oxidative stress response, iron acquisition/storage, and damage repair are the main cellular responses to arsenic exposure. The study provides useful insights into the acquisition, detoxification, and adaptation mechanisms among Xoo populations to adapt under arsenic-rich environmental conditions.
2021-05-17 | GSE163417 | GEO
Project description:Soil microbiomes and arsenic-transforming microorganisms
Project description:Organohalide-respiring Dehalococcoidia bacteria are one of the few microorganisms capable of transforming chlorinated solvents to benign ethene in anoxic environments. The tceA gene found in these bacteria, coding the trichloroethene-dechlorinating RDase TceA, is frequently detected in contaminated groundwater but not recognized as a biomarker for vinyl chloride detoxification. Here, we demonstrate that the tceA-carrying Dehalococcoides mccartyi (Dhc) strains FL2 and 195 grow with VC as electron acceptor when sufficient vitamin B12 is provided. Global proteomic profiling confirmed the predominant TceA expression in VC-grown Dhc FL2 cells, providing a line of evidence for the implication of TceA in respiratory VC reductive dechlorination.
2020-10-09 | MSV000086254 | MassIVE
Project description:Arsenic transformation in high arsenic groundwater
Project description:Chronic arsenic exposure can lead to various health issues including cancer. There has been a growing concern about co-exposure to various prevalent lifestyle habits and their role in the enhancement of arsenic toxicity. Smokeless tobacco (SLT) products are extensively consumed in many South Asian countries, where their use frequently co-occurs with exposure to arsenic from contaminated groundwater. To decipher the oral epithelial cell responses to arsenic and SLT alone and in co-exposure, we performed multi-omics analyses of DNA methylome, transcriptomic reprogramming and genotoxic effects in controlled experimental settings. Chronic exposure studies revealed hypomethylation of genes involved in inflammation response and apoptosis, further corroborated by the upregulation of genes involved in these processes due to arsenic and the combined treatment in acute exposure setting. Next, to validate the omics results at the phenotypic level, we observed a dose dependent decrease in cell viability, induction of DNA damage, cell cycle changes, and an increase in apoptotic cells, with the most pronounced effects observed under arsenic and SLT co-exposure conditions. The observed DNA damage was likely the result of apoptosis induction, as chronic exposure experiments based on whole-exome sequencing did not reveal increased mutagenicity following the arsenic and/or SLT exposure. Our integrative omics study provides insights into both chronic and acute responses to arsenic and SLT co-exposure, with both types of responses converging on some of the same mechanisms. We identified large-scale epigenomic and transcriptomic reprograming associated with arsenic and SLT co-exposure, alongside genotoxic effects presumably manifesting as consequences of apoptosis induction. The findings point to a role of arsenic and SLT in altering key molecular responses, especially in the context of the co-exposure, and call for further studies in humans in the areas of exposure, to validate the observed mechanisms.
Project description:Chronic arsenic exposure can lead to various health issues including cancer. There has been a growing concern about co-exposure to various prevalent lifestyle habits and their role in the enhancement of arsenic toxicity. Smokeless tobacco (SLT) products are extensively consumed in many South Asian countries, where their use frequently co-occurs with exposure to arsenic from contaminated groundwater. To decipher the oral epithelial cell responses to arsenic and SLT alone and in co-exposure, we performed multi-omics analyses of DNA methylome, transcriptomic reprogramming and genotoxic effects in controlled experimental settings. Chronic exposure studies revealed hypomethylation of genes involved in inflammation response and apoptosis, further corroborated by the upregulation of genes involved in these processes due to arsenic and the combined treatment in acute exposure setting. Next, to validate the omics results at the phenotypic level, we observed a dose dependent decrease in cell viability, induction of DNA damage, cell cycle changes, and an increase in apoptotic cells, with the most pronounced effects observed under arsenic and SLT co-exposure conditions. The observed DNA damage was likely the result of apoptosis induction, as chronic exposure experiments based on whole-exome sequencing did not reveal increased mutagenicity following the arsenic and/or SLT exposure. Our integrative omics study provides insights into both chronic and acute responses to arsenic and SLT co-exposure, with both types of responses converging on some of the same mechanisms. We identified large-scale epigenomic and transcriptomic reprograming associated with arsenic and SLT co-exposure, alongside genotoxic effects presumably manifesting as consequences of apoptosis induction. The findings point to a role of arsenic and SLT in altering key molecular responses, especially in the context of the co-exposure, and call for further studies in humans in the areas of exposure, to validate the observed mechanisms.
Project description:To further characerize the arsenic trioxide (ATO) resistance in acutepromyelocytic leukemia, we had made NB4 cell line (arsenic sensitive) to be resistant to arsenic by exposing them to increasing concentration till they are resistant to it and we named it NB4-EV-AsR1. We have also used another cell line (UF1) which is by default resistant to arsenic. Comparing the GEP will give us novel pathways that can contirbute to arseic trioxide.