Similar Datasets
Project description:X1 is the most abundant transcript variant of BRAF mRNA and has a long 3’UTR, but its involvement in post-transcriptional regulatory circuits has not been investigated yet. Here, we describe 20 microRNAs that bind directly to the X1 3’UTR. They were identified in BRAFV600E mutant A375 melanoma cells using miR-CATCHv2.0, an implemented experimental method that combines RNA affinity purification with small RNA sequencing and an ad hoc analytical workflow. X1-targeting microRNAs fall into 4 classes, according to the effect that they exert (decrease/increase in BRAFV600E mRNA and protein levels) and on the mechanism they use to achieve it (destabilization/stabilization of X1 mRNA or decrease/increase in its translation). In many cases, the microRNA-induced variations in BRAFV600E protein levels are coupled to consistent variations in pMEK levels and, in turn, to melanoma cell proliferation and sensitivity to the BRAF inhibitor vemurafenib. However, examples exist of microRNAs that uncouple the degree of activation of the ERK pathway from the levels of BRAFV600E protein. Our study describes miR-CATCHv2.0 as an effective tool for the identification of direct microRNA-target interactions and unveils the complexity of the post-transcriptional regulation to which BRAFV600E and the ERK pathway are subjected in melanoma cells.
2019-03-31 | GSE117641 | GEO
Project description:X1 is the most abundant transcript variant of BRAF mRNA and has a long 3’UTR, but its involvement in post-transcriptional regulatory circuits has not been investigated yet. Here, we describe 20 microRNAs that bind directly to the X1 3’UTR. They were identified in BRAFV600E mutant A375 melanoma cells using miR-CATCHv2.0, an implemented experimental method that combines RNA affinity purification with small RNA sequencing and an ad hoc analytical workflow. X1-targeting microRNAs fall into 4 classes, according to the effect that they exert (decrease/increase in BRAFV600E mRNA and protein levels) and on the mechanism they use to achieve it (destabilization/stabilization of X1 mRNA or decrease/increase in its translation). In many cases, the microRNA-induced variations in BRAFV600E protein levels are coupled to consistent variations in pMEK levels and, in turn, to melanoma cell proliferation and sensitivity to the BRAF inhibitor vemurafenib. However, examples exist of microRNAs that uncouple the degree of activation of the ERK pathway from the levels of BRAFV600E protein. Our study describes miR-CATCHv2.0 as an effective tool for the identification of direct microRNA-target interactions and unveils the complexity of the post-transcriptional regulation to which BRAFV600E and the ERK pathway are subjected in melanoma cells.
2019-03-31 | GSE117640 | GEO
Project description:microRNAs are negative and positive post-transcriptional regulators of BRAF-X1 mRNA
| PRJNA482818 | ENA
Project description:microRNAs are negative and positive post-transcriptional regulators of BRAF-X1 mRNA [miRNA]
| PRJNA482819 | ENA
Project description:microRNAs are negative and positive post-transcriptional regulators of BRAF-X1 mRNA [miR-CATCH]
| PRJNA482822 | ENA
Project description:Here we present miR-CATCHv2.0, an implemented experimental method that allows the identification of the microRNA species directly bound to an RNA of interest. After cross-linking of microRNA::RNA::Ago2 complexes using formaldehyde, the RNA is fragmented using sonication and then subjected to affinity purification using two sets of biotinylated tiling probes (ODD and EVEN). Finally, enriched microRNA species are retrieved by means of small RNA sequencing coupled with an ad hoc analytical workflow. In BRAFV600E mutant A375 melanoma cells, miR-CATCHv2.0 allowed us to identify 20 microRNAs that target X1, the most abundant isoform of BRAF mRNA. These microRNAs fall into different functional classes, according to the effect that they exert (decrease/increase in BRAFV600E mRNA and protein levels) and to the mechanism they use to achieve it (destabilization/stabilization of X1 mRNA or decrease/increase in its translation). microRNA-induced variations in BRAFV600E protein levels are most of the times coupled to consistent variations in pMEK levels, in melanoma cell proliferation in vitro and in sensitivity to the BRAF inhibitor vemurafenib in a xenograft model in zebrafish. However, microRNAs exist that uncouple the degree of activation of the ERK pathway from the levels of BRAFV600E protein. Our study proposes miR-CATCHv2.0 as an effective tool for the identification of direct microRNA-target interactions and, by using such a tool, unveils the complexity of the post-transcriptional regulation to which BRAFV600E and the ERK pathway are subjected in melanoma cells.
| S-EPMC6546394 | biostudies-literature
Project description:Sclerostin is secreted from osteocytes, binds to the Wnt co-receptor Lrp5/6, and affects the interaction between Wnt ligands and Lrp5/6, which inhibits Wnt/β-catenin signals and suppresses bone formation. Sclerostin plays an important role in the preservation of bone mass by functioning as a negative regulator of bone formation. A sclerostin deficiency causes sclerosteosis, which is characterized by an excess bone mass with enhanced bone formation in humans and mice. The expression of sclerostin is positively and negatively regulated by many factors, which also govern bone metabolism. Positive and negative regulators of sclerostin expression and their effects are introduced and discussed herein based on recent and previous findings, including our research.
| S-EPMC9102037 | biostudies-literature
Project description:Every nucleosome across the genome must be disrupted and reformed when the replication fork passes, but how chromatin organization is re-established following replication is unknown. To address this problem, we have developed Mapping In vivo Nascent Chromatin with EdU and sequencing (MINCE-seq) to characterize the genome-wide location of nucleosomes and other chromatin proteins behind replication forks at high temporal and spatial resolution. We find that the characteristic chromatin landscape at Drosophila promoters and enhancers is lost upon replication. The most conspicuous changes are at promoters that have high levels of RNA polymerase II (RNAPII) stalling and DNA accessibility and show specific enrichment for the BRM remodeler. Enhancer chromatin is also disrupted during replication, suggesting a role for transcription factor (TF) competition in nucleosome re-establishment. Thus, the characteristic nucleosome landscape emerges from a uniformly packaged genome by the action of TFs, RNAPII, and remodelers minutes after replication fork passage.
| S-EPMC4855302 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2020-04-01 | GSE120089 | GEO
Project description:In human cells BRAF oncogene is invariably expressed as a mix of two coding transcripts: BRAF-ref and BRAF-X1. These two mRNA isoforms, remarkably different in the sequence and length of their 3'UTRs, are potentially involved in distinct post-transcriptional regulatory circuits. Herein, we identify PARP1 among the mRNA Binding Proteins that specifically target the X1 3'UTR in melanoma cells. Mechanistically, PARP1 Zinc Finger domain down-regulates BRAF expression at the translational level. As a consequence, it exerts a negative impact on MAPK pathway, and sensitizes melanoma cells to BRAF and MEK inhibitors, both in vitro and in vivo. In summary, our study unveils PARP1 as a negative regulator of the highly oncogenic MAPK pathway in melanoma, through the modulation of BRAF-X1 expression.
| S-EPMC10071733 | biostudies-literature