Project description:We hypothesize that DAMPs and non-apoptotic regulated cell death processes are critical players of artery plaque progression with inadequate response to lipid-lowering treatment. Using high performant LC-MS/MS proteomic analysis we aim to uncover the silent mechanisms that govern the existing residual risk of cardiovascular-related mortality in an experimental atherosclerotic model.
Project description:We used microarrays to characterize the global changes in gene expression within the ascending aorta of mice due to conditional disruption of TGF-M-NM-2 signaling in smooth muscle and/or due to heterozygous fibrillin-1 mutation. Myh11-CreERT2.Tgfbr2f/f (abbreviated as Cre.Tgfbr2) mice were cross-bred to Fbn1C1039G/+ (abbreviated as Fbn1C/+) mice and treated with vehicle or tamoxifen for 5 d starting at 4 wk of age to generate 4 groups of animals: 1) Cre.Tgfbr2-Veh: controls with intact TGF-M-NM-2 signaling and wild-type fibrillin-1 expression; 2) Cre.Tgfbr2-Tmx: conditional disruption of Tgfbr2 in smooth muscle with wild-type fibrillin-1 expression; 3) Fbn1C1039G.Cre.Tgfbr2-Veh: heterozygous expression of mutant fibrillin-1 with intact TGF-M-NM-2 signaling; and 4) Fbn1C1039G.Cre.Tgfbr2-Tmx: conditional disruption of Tgfbr2 in smooth muscle with heterozygous expression of mutant fibrillin-1. The animals were euthanized at 6 weeks of age and their ascending aortas (from above the coronary arteries to the first arch branch) were collected and total RNA was extracted.
Project description:Background—YAP, the nuclear effector of Hippo signaling, regulates cellular growth and survival in multiple organs, including the heart, by interacting with TEAD sequence specific DNA-binding proteins. Recent studies showed that YAP stimulates cardiomyocyte proliferation and survival. However, the direct transcriptional targets through which YAP exerts its effects are poorly defined. Methods and Results—To identify genes directly regulated by YAP in cardiomyocytes, we combined differential gene expression analysis in YAP gain- and loss-of-function with genome-wide identification of YAP bound loci using chromatin immunoprecipitation and high throughput sequencing. This screen identified Pik3cb, encoding p110β, a catalytic subunit of phosphoinositol-3-kinase (PI3K), as a candidate YAP effector that promotes cardiomyocyte proliferation and survival. We validated YAP and TEAD occupancy of a conserved enhancer within the first intron of Pik3cb, and show that this enhancer drives YAP-dependent reporter gene expression. Yap gain- and loss-of-function studies indicated that YAP is necessary and sufficient to activate the PI3K-Akt pathway. Like Yap, Pik3cb gain-of-function stimulated cardiomyocyte proliferation, and Pik3cb knockdown dampened the YAP mitogenic activity. Reciprocally, Yap loss-of-function impaired heart function and reduced cardiomyocyte proliferation and survival, all of which were significantly rescued by AAV-mediated Pik3cb expression. Conclusion—Pik3cb is a crucial direct target of YAP, through which the YAP activates PI3K-AKT pathway and regulates cardiomyocyte proliferation and survival. Yap wild type ChIPseq and input
Project description:Conducted proteomics on samples from patients with aortic aneurysm and from non-dilated controls. Furthermore, we investigated both patients with bicuspid aortic valves (BAV) and also the more normal tricuspid aortic valves (TAV). The aim was to elucidate the molecular mechanisms behind the higher propensity of BAV patients to develop aorta dilation and consequent aortic aneurysm.
Project description:Although abnormal TGFbeta signaling is observed in several heritable forms of thoracic aortic aneurysms and dissections including Marfan syndrome, the precise role of TGFbeta signaling in aortic disease progression is still disputed. Using a mouse genetic approach and quantitative isobaric labeling proteomics, we sought to investigate the role of TGFbeta signaling in molecular pathways of pathogenesis associated with development of aortic aneurysm and aortic rupture. This study reports an isoform-specific effect of TGFbeta in MFS aortic disease and the effects of deleting the first hybrid domain of fibrillin-1 on TGFbeta signaling. Distinct molecular differences in mouse models of aneurysm (Fbn_GT-8_plus), of aneurysm and rupture (Fbn1_GT-8_H1delta), and of microdissection (Fbn1_H1delta_plus) were identified, which associated with TGFbeta signaling and extracellular matrix composition, possibly contributing to the development of dissection and rupture. These findings offer new insights into the pathophysiological mechanisms that potentially drive initiation of aortic dissection and could pave the way for development of new treatment targets of aortic disease.
Project description:We characterize a Cre-activated TRAP allele (Rosa26fsTRAP) to show that endothelium-specific activation of Rosa26fsTRAP identifies endothelial cell enriched transcripts, and that cardiomyocyte-restricted TRAP is a useful means to identify genes that are differentially expressed in cardiomyocytes in a disease model. We also show that TRAP is an effective means to study translational regulation, and we several nuclear-encoded mitochondrial genes are under strong translational control. These RNA-seq data show that the TRAP strategy and the Rosa26fsTRAP allele will be useful tools to probe cell type specific transcriptomes, and to study translational regulation. Study TRAP RNA and total RNA in two cases: heart specific tissues, Banding or Sham, using RNA-seq technology.
Project description:To determine the role of specific cis-regulatory elements within the Sox17 endoderm-preferential TSS2 promoter, we generated Sox17mut5 mutant animals and surveyed how this mutation altered Sox17 expression. Gallbladders were isolated from P21 Sox17mut5/mut5 and Sox17+/+ (n = 4 of each genotype), RNA isolated, and bulk RNA-Seq performed.
Project description:We fed hypercholesterolemic mice high fat diet containing either ticagrelor, clopidogrel, or nothing (control) for 16 weeks, isolated the aortae, extracted RNA, and subjected the RNA to RNA-Seq using NGS.