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:Adolescent sensitivity to alcohol is predictive of later alcohol use and is influenced by genetic background. Data from our laboratory suggested that adolescent C57BL/6J and DBA/2J inbred mice differed in susceptibility to dorsal hippocampus-dependent contextual fear learning deficits after acute alcohol exposure. To investigate the biological underpinnings of this strain difference, we examined dorsal hippocampus gene expression via RNA-sequencing after alcohol and/or fear conditioning across male and female C57BL/6J and DBA/2J adolescents. Strains exhibited dramatic differences in dorsal hippocampal gene expression. Specifically, C57BL/6J and DBA/2J strains differed in 3526 transcripts in males and 2675 transcripts in females. We identified pathways likely to be involved in mediating alcohol’s effects on learning, including networks associated with Chrna7 and Fmr1. These findings provide insight into the mechanisms underlying strain differences in alcohol’s effects on learning and suggest that different biological networks are recruited for learning based on genetics, sex, and alcohol exposure.
Project description:Mlycd encodes malonyl-CoA decarboxylase (MCD), which is an enzyme that localizes in the cytosolic, mitochondrial, and peroxisomal compartments and catalyzes the conversion of malonyl-CoA into acetyl-CoA. Malonyl-CoA can be converted into malonylcarnitine (C3DC). Patients with an autosomal recessive defect of MCD and MCD KO mice have pronounced elevations of C3DC. Analysis of plasma C3DC levels in the BxD genetic reference population revealed increased levels in BxD strains that harbor the DBA/2J haplotype at the site of the Mlycd gene. RNA sequencing was performed on two samples of DBA/2J mouse livers and two C57BL/6J mouse livers. Decreased expression of Mlycd gene as well as intronic reads in intron 2 were observed in DBA/2J livers. Long-read sequecing of DBA/2J livers in the Mlycd region confirmed an intracisternal A-particle (IAP) retrotransposon in intron 2 of the DBA/2J Mlycd sequence. To confirm the causal nature of the variant, DBA/2J mice with and without the C57BL/6J variant of Mlycd spliced in were tested for products of MCD enzymatic activity, and the C57BL/6J variant was able to rescue the phenotype seen in the DBA/2J mice.
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: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: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: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.
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: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).