Project description:Because activation of the immune response is dependent on extensive changes in gene expression, it is likely that a major component of inter-individual variation in the immune response is ultimately mediated at the level of gene regulation. Here, we examine the influence of genetic variation on inducible gene expression in the murine immune response. We extracted primary CD4 splenocytes from inbred strains A/J, C57BL/6J, BALB/c, DBA/2J, and 129x1/SvJ (3 animals/strain) and measured mRNA transcript levels using microarrays in both basal state and four hours after stimulation with PMA/Ionomycin. We report strain-specific genome-wide differences in mRNA expression between A/J, Balb/c, C57BL/6J, DBA/2J and 129X1/SvJ inbred mice in CD4 splenocytes in basal, stimulated (4hr, PMA/I) states.
Project description:Regulation of the immune response to Salmonella enterica serovar Typhimurium (S. Typhimurium) infection is a complex process, influenced by the interaction between genetic and environmental factors. Different inbred strains of mice exhibit distinct levels of resistance to S. Typhimurium infection, ranging from susceptible (e.g., C57BL/6J) to resistant (e.g., DBA/2J) strains. However, the underlying molecular mechanisms contributing to the host response remain elusive. In this study, we present a comprehensive proteomics profiling of spleen tissues from C57BL/6J and DBA/2J strains with different doses of S. Typhimurium infection by tandem tag mass coupled with two-dimensional liquid chromatography-tandem mass spectrometry (TMT-LC/LC-MS/MS). We identified and quantified 3,986 proteins, resulting in 475 differentially expressed proteins (DEPs) between C57BL/6J and DBA/2J strains. Functional enrichment analysis unveiled that the mechanism of innate immune responses to S. Typhimurium infection could be associated with several signaling pathways, including the interferon signaling pathway. We experimentally validated the roles of interferon signaling pathway in innate immune response to S. Typhimurium infection using IFN-γ neutralization assay. We further illustrated the roles of macrophage cells and pro-inflammatory cytokines in the mechanisms underlying the resistance to S. Typhimurium using qRT-PCR. Taken together, our results provide new insights into the genetic regulation of the immune response to S. Typhimurium infection in mice and might provide potential protein targets for controlling the infection.
Project description:Susceptible and Resistant mouse strain, e.g. DBA/2J and C57BL/6J respectively, were inoculated with a highly pathogenic H5N1 influenza A virus (A/Hong Kong/213/2003) for 72 hours. Differences in expression were analyzed and use to identify candidate genes and pathways that contributed to the difference in H5N1 pathogenesis in these two strains. Recombinant inbred BXD strains are derived from the DBA/2J and C57BL/6 parent and were used to identify genetic loci associated with resistant to H5N1 infection.
Project description:C57BL/6J (B6) and DBA/2J (D2) are two of the most commonly used inbred mouse strains in neuroscience research. However, the only currently available mouse genome is based entirely on the B6 strain sequence. Subsequently, oligonucleotide microarray probes are based solely on this B6 reference sequence, making their application for gene expression profiling comparisons across mouse strains dubious due to their allelic sequence differences, including single nucleotide polymorphisms (SNPs). The emergence of next-generation sequencing (NGS) and the RNA-Seq application provides a clear alternative to oligonucleotide arrays for detecting differential gene expression without the problems inherent to hybridization-based technologies. Using RNA-Seq, an average of 22 million short sequencing reads were generated per sample for 21 samples (10 B6 and 11 D2), and these reads were aligned to the mouse reference genome, allowing 16,183 Ensembl genes to be queried in striatum for both strains. To determine differential expression, 'digital mRNA counting' is applied based on reads that map to exons. The current study compares RNA-Seq (Illumina GA IIx) with two microarray platforms (Illumina MouseRef-8 v2.0 and Affymetrix MOE 430 2.0) to detect differential striatal gene expression between the B6 and D2 inbred mouse strains. We show that by using stringent data processing requirements differential expression as determined by RNA-Seq is concordant with both the Affymetrix and Illumina platforms in more instances than it is concordant with only a single platform, and that instances of discordance with respect to direction of fold change were rare. Finally, we show that additional information is gained from RNA-Seq compared to hybridization-based techniques as RNA-Seq detects more genes than either microarray platform. The majority of genes differentially expressed in RNA-Seq were only detected as present in RNA-Seq, which is important for studies with smaller effect sizes where the sensitivity of hybridization-based techniques could bias interpretation. There are 5 male and 5 female C57BL/6J animals and 5 male and 5 female DBA/2J. These are adult, naïve animals. One array is run for each animal for a total of 20 Mouse MOE430 2.0 arrays. The purpose is to determine baseline (naïve) gene expression differences in striatum for these two inbred strains. There are 12 male C57BL/6J animals and 12 male DBA/2J. These are adult, naïve animals. One array is run for each animal for a total of 24 Mouse Ref8 v2 arrays. The purpose is to determine baseline (naïve) gene expression differences in striatum for these two inbred strains. ***This submission represents the microarray component of the study
Project description:We hypothesize that gene expression in the aging lungs of these two strains of mice are divergent thus contributing to the disparity in the phenotypes. More specifically, (1) Aging DBA/2J mice compared to aging C57BL/6 mice are known to be accelerated in their lung physiology and morphometry; (2) C57BL/6J are known to have longer natural longevity than DBA/2J mice. In order to test these hypotheses at the gene expression level, we utilized microarray analysis to examine transcriptional differences between aging lungs of both strains of mice. Keywords: comparative expression profiling
Project description:Natural variation in protein expression is common in all organisms and contribute to phenotypic differences among individuals. While variation in gene expression at the transcript level has been extensively investigated, the genetic mechanisms underlying variation in protein expression have lagged considerably behind. Here we investigate genetic architecture of protein expression by profiling a deep mouse brain proteome of two inbred strains, C57BL/6J (B6) and DBA/2J (D2), and their reciprocal F1 hybrids using two-dimensional liquid chromatography coupled with tandem mass spectrometry (LC/LC-MS/MS) technology. By comparing protein expression levels in the four mouse strains, we observed 329 statistically significant differentially expressed proteins between the two parental strains and identified four common inheritance patterns, including dominant, additive, over- and under-dominant expression. We further applied the proteogenomic approach to detect variant peptides and define protein allele-specific expression (pASE).
Project description:Expression profiling of liver tissue from 111 F2 female mice resulting from a cross between C57BL/6J and DBA/2J inbred mouse strains. Mice were feed a chow diet for 12 months followed by 4 months on an atherogenic high-fat, high-cholesterol diet. Parental and F2 mice were killed at 16 months of age. The livers were removed immediately and flash frozen for expression profiling. See Schadt, et al., Nature , Vol 422(6929):297-302 for details. Keywords = Genetics of Gene Expression Keywords = mouse Keywords = C57BL6 Keywords = DBA Keywords: repeat sample
Project description:Susceptible and Resistant mouse strain, e.g. DBA/2J and C57BL/6J respectively, were inoculated with a highly pathogenic H5N1 influenza A virus (A/Hong Kong/213/2003) for 72 hours. Differences in expression were analyzed and use to identify candidate genes and pathways that contributed to the difference in H5N1 pathogenesis in these two strains. Recombinant inbred BXD strains are derived from the DBA/2J and C57BL/6 parent and were used to identify genetic loci associated with resistant to H5N1 infection. Female 6-8 weeks old animals were inoculated with H5N1 virus or not and 72 hours later the lungs were obtained and immediately homogenized in Trizol. The extracted RNA was submitted for Affymetrix Gene expression arrays. Differences in gene-expression were determined and used to identify candidate genes and pathways that are important for disease severity and susceptiblity to H5N1 virus.
Project description:We hypothesize that gene expression in the aging lungs of these two strains of mice are divergent thus contributing to the disparity in the phenotypes.re specifically, (1) Aging DBA/2J mice compared to aging C57BL/6 mice are known to be accelerated in their lung physiology andrphometry; (2) C57BL/6J are known to have longer natural longevity than DBA/2J mice. In order to test these hypotheses at the gene expression level, we utilized microarray analysis to examine transcriptional differences between aging lungs of both strains of mice. Experiment Overall Design: This study utilizes microarray analysis to test these hypotheses. Three sets of lungs were harvested from both strains at each time point (C57BL/6J: 2, 18, AND 26s; DBA/2J: 2 and 18s). RNA was isolated and used for global gene expression profiling (Affymetrixuse 430 2.0 array). Statistically significant gene expression was determined as a minimum 6 counts of 9 pairwise comparisons, minimum 1.5-fold change, and p < 0.05. Further, Absolute | FC - FC SEM | >= 1.5.