Project description:P53 activation in response to cellular stress has long been known to result in downregulation of c-myc, a gene that is frequently overexpressed in cancer due to its role in promoting cellular proliferation. However, the mechanism underlying this p53 dependent myc repression is poorly understood. Here we report p53 regulation of the lncRNA PVT1, a neighboring myc gene which is upregulated following p53 activation via p53 binding to a canonical p53 response element (p53RE) in the first intron of PVT1. Specifically, we find that p53 activation results in induction of an isoform of PVT1 initiated from an alternative first exon, which we have termed PVT1alt. When the PVT1 p53RE is mutated and PVT1alt induction is inhibited, we observe increased levels of myc mRNA in cells undergoing DNA damage or oncogenic stress and corresponding increases in cellular proliferation. The PVT1alt RNA is required for this p53-dependent myc repression, suggesting a important growth suppressive role for this lncRNA in the p53 response. Our study reveals a novel mode of myc regulation in cis by an alternative lncRNA isoform, providing insight into an important mechanism of crosstalk between the p53 and myc transcriptional networks.

2020-01-20 | GSE126940 | GEO

Next Generation Sequencing Facilitates Quantitative Analysis for H3K27ac mediated chromatin conformation capture of Wild Type and PVT1 Knockdown by CRISPRi in MDA-MB-231 human breast cancer cell line

Project description:CRISPRi targeting PVT1 specifically decrease PVT1-MYC interaction

2018-05-31 | GSE97585 | GEO

N6-methyladenosine Modification of lncRNA Pvt1 Governs Epidermal Stemness

Project description:Dynamic chemical modifications of RNA represent novel and fundamental mechanisms that regulate stemness and tissue homeostasis. Rejuvenation and wound repair of mammalian skin are sustained by epidermal progenitor cells, which are localized within the basal layer of the skin epidermis. N6-methyladenosine (m6A) is one of the most abundant modifications found in eukaryotic mRNA and lncRNA (long non-coding RNA). In this report, we survey changes of m6A RNA methylomes upon epidermal differentiation, and identify Pvt1, a lncRNA whose m6A modification is critically involved in sustaining stemness of epidermal progenitor cells. With genome-editing and a mouse genetics approach, we show that ablation of m6A methyltransferase or Pvt1 impairs the self-renewal and wound healing capability of skin. Mechanistically, methylation of Pvt1 transcripts enhances its interaction with MYC and stabilizes the MYC protein in epidermal progenitor cells. Our study presents a global view of epitranscriptomic dynamics that occur during epidermal differentiation and identifies the m6A modification of Pvt1 as a key signaling event involved in skin tissue homeostasis and wound repair.

2021-02-01 | GSE165912 | GEO

A renal cancer-associated, renal tubule-specific, HIF-binding enhancer of oncogenic MYC and PVT1 expression

Project description:Clear cell renal cell carcinoma is characterized by loss of function of the von Hippel-Lindau tumor suppressor gene (VHL) and unrestrained activation of hypoxia inducible transcription factors (HIF). Genetic and epigenetic determinants can impact on HIF pathways. A recent genome-wide association study identified single nucleotide polymorphisms (SNPs) in an intergenic region on chromosome 8 that modify the risk of developing renal cancer. The SNPs are located in a putative regulatory region between the oncogenes MYC and PVT1. Using capture C assay and genome editing we show that HIF-binding to this regulatory element is necessary to trans-activate MYC and PVT1 expression specifically in cells of renal tubular origins. Moreover, we demonstrate that the risk associated polymorphisms increase chromatin accessibility and activity as well as binding of HIF to the enhancer. These findings further strengthen the hypothesis that genetic variation at HIF-binding sites modulates the oncogenic transcriptional output of the VHL-HIF axis and provide a functional explanation for disease associated effects of SNPs in ccRCC.

2017-02-12 | GSE84444 | GEO

Next Generation Sequencing Facilitates Quantitative Analysis of allele specific transcription of PVT1 and MYC in mouse nueronal progenitor clonal cells

Project description:Next Generation Sequencing Facilitates Quantitative Analysis of allele specific transcription of PVT1 and MYC in mouse nueronal progenitor clonal cells

| PRJNA415860 | ENA

Next Generation Sequencing Facilitates Quantitative Analysis of Wild Type and PVT1 Knockdown by CRISPRi in MDA-MB-231 human breast cancer cell line

Project description:Induced MYC expression by CRISPRi targeting PVT1 was validated by RNA-seq

2018-05-31 | GSE97587 | GEO