Project description:RNA seq analysis was conducted to determine gene expression in the day 14 ovine conceptus. This was used in conjunction with the day 14 PPARG ChIP-seq analysis to identify genes bound by PPARG which were also expressed or not expressed in the day 14 conceptus. Understanding changes in gene expression during early pregnancy is critical to improving fertility and reproductive efficiency in ruminants. RNA seq analysis of 4 conceptuses from 4 individual Day 14 pregnant columbia/rambouillet crossbred ewes
Project description:PPARG ChIP seq analysis was conducted to determine genes bound by and potentially regulated by PPARG in the developing ovine conceptus. Determination of gene regulation by prostaglandins through PPARG helps to improve our understanding of early pregnancy events and provides a basis for strategies to improve fertility and reproductive efficiency in ruminants. PPARG ChIP seq analysis of 4 conceptuses from 4 individual Day 14 pregnant columbia/ramboulette crossbred ewes
Project description:To demonstrate that the P. multistriata gene MRP3 is responsible for sex determination, we overexpressed it in a mating type minus strain. The transgenic strain generated displayed sex reversal and behaved like a strain of the opposite mating type. In this study, we compared the gene expression profile of the wild type versus the transformed strain.
Project description:Pitx2 is the homeobox gene located in proximity to the human 4q25 familial atrial fibrillation locus. Pitx2 haploinsufficient mice are prone to pacing induced atrial fibrillation indicating that reduced Pitx2 promotes an arrhythmogenic substrate within the atrium. Here, we inactivated Pitx2 in postnatal heart and discovered that unstressed adult Pitx2 mutant mice had sinus node dysfunction with impaired atrial conduction, an arrhythmia closely associated with atrial fibrillation. A genome-wide search for Pitx2 transcriptional targets using ChIP-sequencing and RNA expression profiling shows that Pitx2 represses target genes encoding cell junction proteins, ion channels, and critical transcriptional regulators many of which have been implicated in human atrial fibrillation by genome wide association studies. Our findings unveil a Pitx2 postnatal arrhythmogenic function, novel Pitx2 target genes relevant to atrial fibrillation, and reveal that Pitx2 stabilizes the intercalated disc in postnatal atrium. Genomic occupancy profiling of transcriptional factor Pitx2 in postnatal heart.
Project description:Purpose: The goals of this study are to determine the effect of microRNA-17 overexpression on 20,803 human genes in RASFs using Ion ProtonTM System platform. Human RASFs from two RA patients were transfected with pre-miR-17 or NC-pre-miR for 48 h and total RNA was prepared using miRNeasy kit (Qiagen). Total RNA integrity was checked using an Agilent Technologies 2100 Bio analyzer (Santa Clara, CA). 10 ng of high quality RNA was used to make cDNA for amplification with the Ion AmpliSeq Transcriptome Human Gene Expression kit (ThermoFisher Scientific). The cDNA was subjected to 12 cycles of amplification with panel primers and barcoded with adapters as recommended. Resulting sequencing libraries were quantified by qPCR using SYBR FAST master mix from KapaBiosystems (Wilmington, MA). Sets of eight libraries were balanced, pooled and sequencing beads produced on an Ion Chef. Sequencing was performed on an Ion P1 semi-conductor sequencing chip using an Ion Proton⢠System (ThermoFisher Scientific, Grand Island, NY). Data was collected and primary analysis performed using Torrent Suite software version 5.0.3. Reads were mapped to the panel and expression values determined. R Software version R-3.2.3 was used to generate heatmap. Among the panel of 20,803 genes, the expression of 15,067 genes as shown in the representative heat map was observed in pre-miR-17 and NC-pre-miR transfected RASFs. A total of 664 significantly modulated genes (301 upregulated and 363 downregulated) using Student âtâ test were further utilized for the IPA analysis. The result of IPA predicted the protein ubiquitin pathway as a major canonical pathway affected by the differentially regulated genes. Interestingly, IPA analysis generated an interactome that showed connectivity among various ubiquitin ligases, NF-ÔB family, AP-1/cJun, 20S and 26S proteasome system. Conclusion: Our results clearly shows the major pathways affected by miR-17 overexpression in RASFs were Protein ubiquitination related. mRNA profiles of pre-miR-17 and NC-pre-miR transfected RASFs were generated by AmpliSeq, in duplicate, using Ion Proton⢠System.
Project description:Obesity is well recognized as a risk factor for coronary heart disease and mortality. The relationship between abdominal obesity and ischemic stroke remains less clear. Previous publication showed the obesity is an independent, potent risk factor for ischemic stroke in all race-ethnic groups. It is a stronger risk factor than BMI and has a greater effect among younger persons. The goal of this experiment was to compare genome wide enrichment of H3K9ac histone mark profile of white blood cells of healthy controls, patients with obesity and/or stroke in order to understand the histone modifications differences behind the different phenotypes. There were 3 subjects in each group.
Project description:Background: Repair of DNA damage requires chromatin remodeling to permit removal of the lesions. How nucleosomes are remodelled to initiate repair of DNA damage remains largely unknown. Here, we describe how chromatin is altered during repair of UV-induced DNA damage at the level of the linear organisation of nucleosomes. Results: Using MNase-seq, we identified a subset of nucleosomes in the genome that are remodelled in UV-damaged wild-type yeast cells. We mapped the genomic location of these nucleosomes, showing that they contain the histone variant H2A.Z. The remodelling observed is consistent with histone exchange or eviction at these positions. This depends on the yeast SWI/SNF global genome nucleotide excision repair (GG-NER) chromatin-remodelling complex. Remarkably, we found that in the absence of DNA damage, the GG-NER complex occupies chromatin at nucleosome free regions separating adjacent nucleosomes. This establishes the nucleosome structure at these genomic locations, which we refer to as GG-NER complex binding sites (GCBS’s). We observed that these sites are frequently located precisely at certain boundary regions that delineate chromasomally interacting domains (CIDs). These boundaries define chromosomal domains of higher-order nucleosome-nucleosome interaction. We demonstrate that the GG-NER complex redistributes following remodelling of these nucleosomes after DNA damage taking up genomic positions located within the CIDs. This permits the efficient removal of DNA damage at these sites. Conclusions: We argue that organising DNA repair in the genome as described may define origins of DNA repair that greatly reduces the genomic search space for DNA damage recognition, thus ensuring the efficient repair of damage in chromatin.
Project description:FOXL2 is a transcription factor essential for female fertility, expressed in somatic cells of the ovary, notably granulosa cells. In the mouse, Foxl2 deletion leads to partial sex reversal postnatally. However, deletion of the gene in 8-week-old females leads to granulosa to Sertoli cell transdifferentiation. We hypothesised that different outcomes of Foxl2 deletion in embryonic versus adult ovary may depend on a different role played across ovarian development. Therefore, we characterised the dynamics of gene expression and chromatin accessibility changes in purified murine granulosa cells across key developmental stages (E14.5, 1 and 8 weeks). We then performed genome-wide identification of FOXL2 target genes and on-chromatin interacting partners by ChIP-SICAP. We found that FOXL2 regulates more genes at postnatal stages, through the interaction with factors regulating primordial follicle activation (PFA), such as NR5A2, and others regulating steroidogenesis including AR and ESR2. As a proof of principle experiment, we chose one FOXL2 interactor, Ubiquitin specific protease 7 (USP7) and showed that deletion of this gene in granulosa cells leads to a blockage of PFA, impaired ovary development and sterility. Our study constitutes a comprehensive resource for exploration of the molecular mechanisms of ovarian development and causes of female infertility.
Project description:Glucocorticoid receptor (GR) is an essential transcription factor (TF), controlling metabolism, development and immune responses. SUMOylation regulates chromatin occupancy and target gene expression of GR in a locus-selective manner, but the mechanism of regulation has remained elusive. Here, we show using selective isolation of chromatin-associated proteins that the protein network around chromatin-bound GR is affected by SUMOylation, with several nuclear receptor coregulators and chromatin modifiers being more avidly associated with SUMOylation-deficient than SUMOylation competent GR. This difference is reflected in our chromatin accessibility and gene expression data, showing that the SUMOylation-deficient GR is more potent in opening chromatin at glucocorticoid-regulated enhancers and inducing expression of their target loci. Our results thus show that SUMOylation determines GR specificity by regulating the chromatin protein network and accessibility at GR-driven enhancers. We speculate that a similar mechanism is utilized by many other SUMOylated TFs.