Project description:We found that mainstream cigarette smoking (4 cigarettes/day, 5 days/week for 2 weeks using Kentucky Research Cigarettes 3R4F) resulted in >20% decrease in the percentage of normal Paneth cell population in Atg16l1 T300A mice but showed minimal effect in wildtype littermate control mice, indicating that Atg16l1 T300A polymorphism confers sensitivity to cigarette smoking-induced Paneth cell damage. We performed cohousing experiments to test if Paneth cell phenotype is horizontally transmissible as is microbiota. Atg16l1 T300A and littermate controls that were exposed to cigarette smoking were used as microbiota donors, and these donor mice were exposed to smoking for 2 weeks prior to cohousing. Separate groups of Atg16l1 T300A and littermate controls that were not exposed to cigarette smoking were used as microbiota recipients. The microbiota recipients were co-housed with microbiota donors of the same genotype for 4 weeks, during this period the donors continued to be exposed to cigarette smoking. Cigarette smoking was performed using smoking chamber with the dosage and schedule as described above. At the end of the experiment, the fecal microbiota composition was analyzed by 16S rRNA sequencing.
Project description:Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) infection of 3rd trimester pregnant pigs can result in transmission of the virus to the fetus and ultimately death in utero or postnatally. Little is known about the immune response to infection at the maternal-fetal interface and in the fetus itself, or the molecular events behind virus transmission and disease progression in the fetus. To investigate these processes, RNA-sequencing of two tissues, uterine endothelium adjacent to the umbilical attachment site and fetal thymus, was performed 21 days post challenge on four groups of fetuses selected from a large PRRSV challenge experiment of pregnant gilts. RNA-seq experiment compared gene expression between four different groups of fetuses (n=12 per group): control (CON-uninfected fetuses from mock inoculated gilts), UNINF (uninfected fetuses from PRRSV-inoculated gilts), INF (infected fetuses from PRRSV-inoculated gilts), and meconium-stained fetuses (MEC-meconium-stained fetuses from PRRSV-inoculated gilts) and investigated two tissues: uterine endometrium (with adherent placental tissue) at the site of umbilical attachment and fetal thymus (96 samples in total). Three contrasts were performed for the differential expression (edgeR) and network (WGCNA) analyses: UNINF v CON, INF v UNINF, and MEC v INF.
Project description:We profiled transcriptome and accessible chromatin landscapes in intestinal epithelial cells (IECs) from mice reared in the presence or absence of microbiota. We show that regional differences in gene transcription along the intestinal tract were accompanied by major alterations in chromatin organization. Surprisingly, we discovered that microbiota modify host gene transcription in IECs without significantly impacting the accessible chromatin landscape. Instead, microbiota regulation of host gene transcription might be achieved by differential expression of specific TFs and enrichment of their binding sites in nucleosome depleted CRRs near target genes. Our results suggest that the chromatin landscape in IECs is pre-programmed by the host in a region-specific manner to permit responses to microbiota through binding of open CRRs by specific TFs. mRNA and accessible chromatin (DNase-seq) profiles from colonic and ileal IECs were compared between conventionally-raised (CR), germ-free (GF), and conventionalized (CV) C57BL/6 mice.