Project description:We report the effects of 1,25(OH)2D3 treatment on the microRNA expression in human muscle cells Primary cultures of human muscle cells were treated with 1,25(OH)2D3 or vehicle for 48 hours.
Project description:We report the effects of 1,25(OH)2D3 treatment on the mRNA expression in human muscle cells Primary cultures of human muscle cells were treated with 1,25(OH)2D3 or vehicle for 48 hours.
Project description:Vitamin D receptors (VDR) are abundantly expressed in developing zebrafish as early as 48 hours post-fertilization, and prior to the development of a mineralized skeleton, and mature intestine and kidney. We probed the role of VDR in zebrafish biology by examining changes in expression of RNA by whole transcriptome shotgun sequencing (RNA-seq) in fish treated with picomolar concentrations of the VDR ligand and hormonal form of vitamin D3, 1a,25-dihydroxyvitamin D3 (1a,25(OH)2D3). We observed significant changes in RNAs encoding proteins of fatty acid, amino acid, and xenobiotic metabolism pathways, and RNAs of transcription factors, leptin, peptide hormones, receptor-activator of NFkB ligand (RANKL), and calcitonin-like ligand receptor pathways. Early small, and subsequent massive changes in >10% of expressed cellular RNAs were observed. At day 2 (24h 1a,25(OH)2D3-treatment), only 5 RNAs were differentially expressed (hormone vs. vehicle). On day 4 (72h-treatment), 78 RNAs; on day 6 (120h-treatment) 1040 RNAs; and on day 7 (144h-treatment), 1755 RNAs were differentially expressed in response to 1a,25(OH)2D3. Fewer RNAs (n = 482) were altered in day 7 embryos treated for 24h with 1a,25(OH)2D3 vs. those treated with hormone for 144h. At 7 days, in 1a,25(OH)2D3-treated embryos, pharyngeal cartilage was larger and mineralization was greater. Changes in expression of RNAs for transcription factors, peptide hormones, and RNAs encoding proteins integral to fatty acid, amino acid, leptin, calcitonin-like ligand receptor, RANKL and xenobiotic metabolism pathways, demonstrate heretofore unrecognized mechanisms by which 1a,25(OH)2D3 functions in vivo in developing eukaryotes. Zebrafish embryos were obtained from mating of Segrest wild-type (SWT) parents under controlled barrier conditions, in the Mayo Clinic Zebrafish Core Facility, in Instant Ocean media . Zebrafish embryos (25-30) were placed in 20 mL embryo medium (pH 7.2) containing 1-phenyl-2-thiourea (PTU) (0.003% (w/v) and were maintained at 28-30 oC. At 24 hpf (1 day post fertilization, dpf), 10 microliters of 1a,25(OH)2D3 in ethanol was added to embryos maintained in 20 mL fresh embryo medium with PTU. The final concentration of 1a,25(OH)2D3 was 300 pM. Control zebrafish were treated with 10 microliters ethanol alone (vehicle controls). The medium containing either 300 pM 1a,25(OH)2D3 or vehicle was changed every 24 h . In experiment 1, at 2, 4, 6 and 7 dpf embryos/larvae were removed and immediately frozen at -80 0C for later RNA preparations. 25-30 embryos per set were used for preparation on RNA. At the same times, 7-12 embryos were fixed in 4% paraformaldehyde in 0.75 X DulbeccoM-bM-^@M-^Ys phosphate buffered saline (DPBS). In experiment 2, 6 dpf larvae were treated with 1a,25(OH)2D3 (300 pM) or vehicle for 24 h. RNA was prepared from three sets of larvae.
Project description:Functional and structural dysfunction of the blood brain barrier (BBB) leads to severe alterations in brain physiology and is believed to trigger neurodegeneration. To investigate the molecular mechanisms driving the BBB dysfunction, very few human BBB cell culture models are available;of which, the human microvascular endothelial cell line (hCMEC/D3) is the most widely used. Thus far, array-based approaches or targeted seqeuncing based approaches have been employed to characterize the gene expression of the hCMEC/D3 model. However,The goal of this study is to perform deep transcriptomic sequencing of the BBB cell line and obtain features like gene expression, expressed single nucleotide variants, alternate splice forms, circular RNAs, long non-coding RNAs and micro RNAs. We have developed blood brain barriers transcriptomics landscape using RNA and micro RNA sequencing data obtained from replicates of hCMEC/D3 BBB cell line.
Project description:Termination of RNAPII transcription is associated with RNA 3â end formation. For coding genes, termination is initiated by the cleavage/polyadenylation machinery. In contrast, a majority of noncoding transcription events in S. cerevisiae do not rely on RNA cleavage for termination, but instead terminate via a pathway that requires the Nrd1-Nab3-Sen1 (NNS) complex. Here we show that the S. pombe ortholog of Nrd1, Seb1, does not function in NNS-like termination, but promotes polyadenylation site selection of coding and noncoding genes. We found that Seb1 associates with 3â end processing factors, is enriched at the 3â end of genes, and binds RNA motifs downstream of cleavage sites. Importantly, a deficiency in Seb1 resulted in widespread changes in 3â UTR length as a consequence of increased alternative polyadenylation. Given that Seb1 levels affected the recruitment of conserved 3â end processing factors, our findings indicate that the conserved RNA-binding protein Seb1 co-transcriptionally controls alternative polyadenylation. Two biological replicates of Seb1 and Control (parental strain) CRAC experiments
Project description:Liver fibrosis is a reversible wound-healing response to liver injury and hepatic stellate cells (HSCs) are central cellular players that mediate hepatic fibrogenesis. However, the molecular mechanisms that govern this process remain unclear. Here, we reveal a novel cistromic circuit in HSCs comprising the vitamin D receptor (VDR) and SMAD transcription factors that restrains the intensity of hepatic fibrogenesis. Ligand-activated VDR suppresses TGFβ1-induced pro-fibrotic gene expression in HSCs. Administration of a vitamin D analogue, calcipotriol, diminishes the fibrotic response in a mouse model of liver fibrosis, while VDR knockout mice spontaneous develop extensive hepatic fibrosis by age 6 months. Using ChIP-Seq, we find that the anti-fibrotic properties of VDR are due to crosstalk with SMAD, mediated by their co-occupancy of DNA-binding sites on pro-fibrotic genes. Specifically, SMAD binding potentiates local chromatin accessibility to enhance VDR recruitment at the same cis-regulatory elements, which reciprocally antagonizes the interaction between SMAD3 and chromatin and limits the assembly of transcriptional activation complexes at fibrotic genes, a process that is enhanced by the presence of VDR agonists. These results not only establish this coordinated VDR/SMAD cistromic circuit as a master regulator of hepatic fibrogenesis, but also support VDR as a potential drug target to ameliorate liver fibrosis. Identification of VDR, SMAD3 and H3 binding sites in human stellate LX2 cells that were pre-treated with calcipotriol (100nM) for 16 hrs (where calcipotriol treatment is indicated) followed by incubation of calcipotriol (100nM) or TGFβ1 (1ng/ml) for another 4 hours (where indicated).
Project description:The phosphatases PP1 and PP2A are responsible for the majority of dephosphorylation reactions on phosphoserine (pSer) and –threonine (pThr), and are involved in basically all cellular processes and many related diseases. They are thought to have no appreciable intrinsic substrate specificity, but to gain specificity only in their holoenzyme forms. Through the development of a peptide library approach and application of a complementary phosphoproteomics assay, we uncover that PP1 and PP2A show intrinsic specificity towards pThr over pSer, as well as toward the sequence context surrounding the phospho-site. Our data reveal that PP1 is a key phosphatase of the 14-3-3 protein binding motif. This result enabled us to establish a previously unknown role for PP1 as regulator of the GRB-associated-binding-protein 2 (Gab2)/14-3-3 complex, exemplifying predictive potential of the data. Thus, our work should serve as a rich resource for (de)phosphorylation studies covering multiple cellular processes and phosphoproteins.
Project description:MicroRNAs (miRNA) have alternative forms known as isomiRs, which differ from each other by a few nucleotides. Next generation sequencing platforms facilitate identification of these isomiRs and recent discoveries regarding their functional importance have increased our understandings of the regulatory complexities of the microRNAome. Observed changes in the miRNA profiles in mosquitoes infected with flaviviruses have implicated small RNAs in the interactions between viruses and their vectors. Here we analysed the isomiR profiles of both uninfected and infected blood fed Aedes aegypti mosquitoes with a major human pathogen, Dengue virus at two time points post-infection. We found noticeable changes to the isomiR expression profile in response to infection and aging. Data analysis revealed a distinct bias towards isomiR production in the mature miRNA as opposed to the star strand. Furthermore, we noticed that only in 40% of Ae. aegypti miRNAs, the most abundant reads for each particular miRNA match the exact sequence reported in the miRbase. The isomiR expression variations between an Ae. aegypti embryonic cell line (Aag2) and whole mosquitoes demonstrated a tissue-specific pattern of isomiR production. Our results illustrated a bias for certain types of isomiRs for each miRNA. The findings presented in this study also provide evidence that isomiR production is not a random phenomenon and may be important in DENV colonisation of its vector. Examination of isomiR production rate in DENV infected and non infected mosquitoes