Project description:To gain a comprehensive view of the host response to pathogens within these tissues, we determined the transcriptional profiles of intestinal lymphatic tissue infected with Y. enterocolitica. Expression analysis using Affymetrix GeneChips revealed a complex host response in the Peyer’s patches (PP) and mesenteric lymph nodes (MLN) following oral infection with Y. enterocolitica. Keywords: Disease state analysis
Project description:Long-term exposure to particulate air pollutants has been linked to increased incidence of Type 2 Diabetes (T2DM). Recently, we showed that the gaseous pollutant, O3, induced glucose intolerance, and increased serum leptin and epinephrine in Brown Norway rats. In this study, we hypothesized that O3 exposure will cause broad scale changes in metabolic homeostasis involving liver, muscle and adipose tissues, and that serum metabolomic and liver transcriptomic profiling will provide mechanistic insights into pollutant-induced metabolic alterations. In the first experiment, male Wistar Kyoto (WKY) rats were exposed to filtered air (FA) or O3 at 0.25, 0.50, or 1.00 ppm, 6h/day for two consecutive days to establish concentration-related effects on glucose tolerance and lung injury. In a second experiment, rats were exposed to FA or 1.0 ppm O3, 6h/day for either one day or two consecutive days and systemic metabolic responses were determined immediately after each exposure or after an 18h recovery period. In WKY rats, O3 increased serum fasting glucose and leptin on day 1. Glucose intolerance persisted through two days of exposure but reversed 18h post second exposure. O3 exposure increased circulating metabolites of glycolysis, long-chain free fatty acids, branched chain amino acids (BCAA) and cholesterol while 1,5- anhydroglucitol, bile acids and metabolites of TCA cycle were decreased, indicating impaired glycemic control, muscle proteolysis and adipose lipolysis. Liver gene expression profile after O3 exposure reflected a response to the serum metabolite changes, as evidenced by increased expression of genes for glycolysis, TCA cycle and gluconeogenesis, and decreased expression of genes involved in steroid and fat biosynthesis. In conclusion, short-term O3 exposure induced hormonal changes and global metabolic disorder reflective of changes in peripheral glucose, lipid, and amino acid metabolism, representative of a stress-response. It remains to be examined if these metabolic alterations contribute to insulin resistance upon chronic exposure.
Project description:Male and female gametocytes are sexual precursor cells essential for transmission of malaria parasite in the mosquitoes. Differentiation of gametocytes to fertile gametes (gametogenesis) relies on the gender-specific transcriptome. However, how the parasites establish distinct repertoire of gene transcription in the male and female gametocytes remains largely unknown. Here, we report that an Apetala2 (AP2) family transcription factor (TF) AP2-O3 operates as a transcription repressor regulating female gametocyte transcriptome. AP2-O3 is specifically localized in the nucleus of the female gametocytes. AP2-O3-deficient parasites produce apparently normal female gametocytes, which fail to differentiate to fully fertile female gametes, leading to developmental arrest in fertilization and early development post-fertilization. AP2-O3 disruption causes massive up-regulation of transcriptionally dormant male genes and simultaneously down-regulation of highly transcribed female genes in female gametocytes. ChIP-seq and EMSA analysis establish AP2-O3 as a transcription repressor that targets a significant proportion of the upregulated male genes by recognizing an eight-base DNA motif in the promoters. In addition, the maternal AP2-O3 is removed after fertilization, which is required for the zygote to ookinete development. These results demonstrate that global transcriptional repression of male genes in the female gametocytes is required for safeguarding female-specific transcriptome and essential for the mosquito transmission of Plasmodium.
Project description:Male and female gametocytes are sexual precursor cells essential for transmission of malaria parasite in the mosquitoes. Differentiation of gametocytes to fertile gametes (gametogenesis) relies on the gender-specific transcriptome. However, how the parasites establish distinct repertoire of gene transcription in the male and female gametocytes remains largely unknown. Here, we report that an Apetala2 (AP2) family transcription factor (TF) AP2-O3 operates as a transcription repressor regulating female gametocyte transcriptome. AP2-O3 is specifically localized in the nucleus of the female gametocytes. AP2-O3-deficient parasites produce apparently normal female gametocytes, which fail to differentiate to fully fertile female gametes, leading to developmental arrest in fertilization and early development post-fertilization. AP2-O3 disruption causes massive up-regulation of transcriptionally dormant male genes and simultaneously down-regulation of highly transcribed female genes in female gametocytes. ChIP-seq and EMSA analysis establish AP2-O3 as a transcription repressor that targets a significant proportion of the upregulated male genes by recognizing an eight-base DNA motif in the promoters. In addition, the maternal AP2-O3 is removed after fertilization, which is required for the zygote to ookinete development. These results demonstrate that global transcriptional repression of male genes in the female gametocytes is required for safeguarding female-specific transcriptome and essential for the mosquito transmission of Plasmodium.
Project description:Long-term exposure to particulate air pollutants has been linked to increased incidence of Type 2 Diabetes (T2DM). Recently, we showed that the gaseous pollutant, O3, induced glucose intolerance, and increased serum leptin and epinephrine in Brown Norway rats. In this study, we hypothesized that O3 exposure will cause broad scale changes in metabolic homeostasis involving liver, muscle and adipose tissues, and that serum metabolomic and liver transcriptomic profiling will provide mechanistic insights into pollutant-induced metabolic alterations. In the first experiment, male Wistar Kyoto (WKY) rats were exposed to filtered air (FA) or O3 at 0.25, 0.50, or 1.00 ppm, 6h/day for two consecutive days to establish concentration-related effects on glucose tolerance and lung injury. In a second experiment, rats were exposed to FA or 1.0 ppm O3, 6h/day for either one day or two consecutive days and systemic metabolic responses were determined immediately after each exposure or after an 18h recovery period. In WKY rats, O3 increased serum fasting glucose and leptin on day 1. Glucose intolerance persisted through two days of exposure but reversed 18h post second exposure. O3 exposure increased circulating metabolites of glycolysis, long-chain free fatty acids, branched chain amino acids (BCAA) and cholesterol while 1,5- anhydroglucitol, bile acids and metabolites of TCA cycle were decreased, indicating impaired glycemic control, muscle proteolysis and adipose lipolysis. Liver gene expression profile after O3 exposure reflected a response to the serum metabolite changes, as evidenced by increased expression of genes for glycolysis, TCA cycle and gluconeogenesis, and decreased expression of genes involved in steroid and fat biosynthesis. In conclusion, short-term O3 exposure induced hormonal changes and global metabolic disorder reflective of changes in peripheral glucose, lipid, and amino acid metabolism, representative of a stress-response. It remains to be examined if these metabolic alterations contribute to insulin resistance upon chronic exposure. Rats were exposed to filtered air (FA) or Ozone at 1 ppm, 6h/day for two consecutive days to establish ozone-exposure related effects on transcriptomic profiles. Samples were taken at three time points: 1 day (1day0hrs) - at the end of the 6 hour exposure period, 2 days (2day0hrs) - at the end of the of the second day 6 hour exposure period) and 2 days 18 hours (2day18hrs) - 18 hours after the 6 hour exposure period on the second day. Total liver RNA was isolated from ~20 mg tissue with a commercially available RNeasy mini kit (Qiagen, Valencia, CA) using silica gel membrane purification. Liver RNA was resuspended in 30μl of RNAse- free water. RNAse inhibitor was added and RNA yield was determined spectrophotometrically on a NanoDrop 1000 (Thermo Scientific, Wilmington, DE). RNA integrity was assessed by the RNA 6000 LabChip® kit using a 2100 Bioanalyzer (Agilent Technologies, Palo Alto, CA). We examined global gene expression changes using the Affymetrix platform (RG- 230 PM Array strip). Biotin-labeled cRNA was produced from total RNA using an Affymetrix “IVT-express labeling kit “(cat# 901229).