Project description:Identifying novel pathways regulating the adaptive immune response in chronic inflammatory diseases such as atherosclerosis is of particular interest in view of developing new therapeutic drugs. Here we report that the lipid receptor GPR55 is highly expressed by splenic B cells and inversely correlates with atheroma plaque size in mice. In human carotid endarterectomy specimen, GPR55 transcript levels were significantly lower in unstable compared to stable carotid plaques. To study the impact of GPR55 deficiency in atherosclerosis, we crossed Gpr55 knockout mice with apolipoprotein E (ApoE) knockout mice and subjected the mice to Western diet for 4 to 16 weeks. Compared to ApoE-/- controls, ApoE-/-Gpr55-/- mice developed larger plaques with increased necrotic core size, associated with elevated circulating and aortic leukocyte counts. Flow cytometry, immunofluorescence and RNA-sequencing analysis of splenic B cells in these mice revealed a hyperactivated B cell phenotype with disturbed plasma cell maturation and immunoglobulin (Ig)G antibody overproduction. Collectively, these discoveries provide new evidence for GPR55 as key modulator of the adaptive immune response in atherosclerosis. Targeting GPR55 could be useful to limit inflammation and plaque progression in patients suffering from atherosclerosis We performed gene expression profiling analysis using data obtained from RNA-seq of female splenic CD19+ B cells isolated from 6 different ApoE-knockout mice and 6 ApoE and Gpr55 double knockout mice, all under C57BL/6J background.
Project description:The small splice variant of the sulfonylurea receptor protein isoform 2A (SUR2A-55) targets mitochondria and enhances mitoKATP activity. In male mice the overexpression of this protein promotes cardioprotection protecting hearts from ischemia reperfusion injury. However, it is unclear what impact this has on the female myocardium as SUR2A and KATP channels are known to be differentially expressed in male and female hearts. To define the impact of SU2R2A-55 on the female heart, RNA seq was performed on hearts from mice with cardiac specific transgenic overexpression of SUR2A-55 (TGSUR2A-55). RNA seq analysis found 227 differnetial expressed genes between WT and TGSUR2A-55 female mouse hearts that were enriched in pathways of cellular metabolism. This was in direct contrast to male mice that had only three differentially expressed genes. Future research directed at the expression and activity of mitoKATP subunits according to sex may elucidate gender specific treatments.
Project description:This SuperSeries is composed of the following subset Series: GSE39746: Argonaute proteins couple chromatin silencing to alternative splicing (exon array) GSE39748: Argonaute proteins couple chromatin silencing to alternative splicing (RNA IP-Seq) Refer to individual Series
Project description:affy_fsh_human - affy_fsh_human - - G protein-coupled receptors (GPCR) are centrally involved in most physiological processes and are a major drug targets. They transduce extracellular signals inside the cells through at least two different mechanisms: i) the classical coupling to heterotrimeric G proteins and ii) a newly discovered beta-arrestin-dependent pathway. The fundamental issue of the respective impacts that these two transduction mechanisms exert on gene regulation has not been clearly addressed to date. To tackle this question, we have developed two mutants of the follicle stimulating hormone (FSH) receptors which do not couple to G proteins upon FSH activation but continue to recruit beta-arrestins and signal through them.-In the present study, we compare the wild-type FSH receptor to either the R466A or the T469F mutants. These two mutations are localized in the second intra cellular loop of the FSH receptor and prevent G protein coupling to the active FSH receptor. Each receptor was permanently expressed in HEK-293 cells at comparable levels. Cells were treated or not for 6 hours with 3 nM FSH. Keywords: treated vs untreated comparison,wt vs mutant comparison 18 arrays - Human GenomeU133A 2.0
Project description:Recent data from our group, demonstrate that infusion of myelin oligodendrocyte glycoprotein (MOG35-55) peptide, leads to induction of MOG35-55-specific Tregs and subsequent suppression of Experimental Autoimmune Encephalomyelitis (EAE), the mouse model of multiple sclerosis. Amelioration of EAE was accompanied by reduced MOG-specific Th1 and Th17 responses in the draining lymph nodes (dLNs). Phenotypic analysis of the dLNs of MOG-infused mice revealed a significant Treg-mediated reduction in the recruitment of 7AAD-CD3-CD19-CD11c+CD11bhighGr-1+ iDCs compared to non-infused control immunized mice. Focusing on the delineation of novel molecules/genes that are involved in the MOG-specific Treg-mediated suppression of autoimmune responses, we have isolated highly purified iDCs from MOG infused and non-infused control immunized mice.
Project description:While Argonaute (AGO) proteins play a major role in transcriptional gene silencing (TGS) in many organisms, their role in the nucleus of somatic mammalian cells remains elusive. Here, we have purified AGO1 and AGO2 chromatin-embedded complexes, and found these proteins associated with previously described partners, but also with chromatin modifiers and, rather unexpectedly, with different splicing factors. Using the CD44 gene as a model for alternative splicing, we show that both AGO1 and AGO2 are required for Protein Kinase C (PKC)-dependent variant exon inclusion. AGO proteins facilitate the spliceosome recruitment and modulate the elongation rate of RNA polymerase II (RNAPII). The recruitment of AGO proteins to CD44 transcribed region is dependent on both the endonuclease Dicer and the chromodomain-containing protein HP1g, and results in locally increased levels of histone H3 lysine 9 (H3K9) methylation on variant exons. Genome wide analysis of splicing in either AGO2 or Dicer null cells showed that the two proteins have similar effects on many splicing events. Finally, sRNAs associated with nuclear AGO2 are mostly in sense orientation relative to protein-coding genes, supporting a role for intragenic antisense non-coding RNAs in the recruitment AGO and splicing factors. Together, our data demonstrate for the first time that the endogenous RNAi pathway is involved in alternative splicing decisions, unravelling a new model in which AGO proteins couple RNAPII elongation and chromatin modification. Deep sequencing of small RNAs (approx. 15-80 nucleotides) bound to either cytoplasmic or chromatin-associated AGO2 complex.