Project description:We developed a method to deconvolute decays of m6A mRNAs and their unmethylated isoforms from total RNAs across the transcriptome and combined this method with the knockdown of m6A reader protein to study the effect on global mRNA turnover.
Project description:We developed a method to deconvolute decays of m6A mRNAs and their unmethylated isoforms from total RNAs across the transcriptome and combined it with the knockdown of m6A reader protein to study it's effect on global mRNA turnover.
Project description:N6-methyladenosine (m6A) is the most prevalent internal modification present in the mRNA of all higher eukaryotes. Here we present that m6A is selectively recognized by human YTH domain family (YTHDF2) protein to regulate mRNA degradation. By using crosslinking and immunoprecipitation, we have identified over 4000 substrate RNA of YTHDF2 with conserved core motif of G(m6A)C. We further estabilshed the role of YTHDF2 in RNA metabolism by a combination of ribosome profiling, RNA sequencing, m6A level quantification and cell-based imaging: the C-terminal domain of YTHDF2 selectively binds to m6A of mRNA and the N-terminal domain is responsive for localizing mRNA from translatable pool to processing body where mRNA decay occurs. PAR-CLIP and RIP was used to identify YTHDF2 binding sites followed by ribosome profling and RNA seq to assess the consequences of YTHDF2 siRNA knock-down
Project description:As the crucial m6A reader, YTHDF2 usually degrades the target mRNAs by recognizing the m6A modified sites, consequently altering m6A levels of each mRNA. In this study, we used m6A MeRIP sequencing to detect the m6A modification alterations in prostate cancer (PCa) cell line after knocking down YTHDF2 and identify how YTHDF2 promote the PCa progression by mediating the mRNA degradation in m6A-dependent way.
Project description:Our study demonstrated that the expression of Igf2bp1 in activated microglia was significantly up-regulated, implying a role of Igf2bp1 in LPS-induced m6A modifications in microglia. To understand the roles of Igf2bp1 on LPS-induced m6A modification in microglia, we performed Igf2bp1 loss-of-function (LOF) approach. Microglia stimulated by LPS were transfected with either scrambled siRNA control or Igf2bp1 siRNA for 48 hours. To m6A modification profiles in control and Igf2bp1 LOF microglia were determined by MeRIP-seq analysis.
Project description:The m6A modification regulates mRNA stability and translation. Here we show that transcriptomic m6A modification is dynamic and the m6A reader protein YTHDF2 promotes mRNA decay during the cell cycle. Depletion of YTHDF2 leads to the delay of mitotic entry due to overaccumulation of WEE1, a negative regulator of CDK1. We demonstrate that WEE1 transcripts contain m6A modification, which promotes their decay through the m6A reader YTHDF2. Moreover, we found that YTHDF2 protein stability is dependent on CDK1 activity. Thus, CDK1, YTHDF2, and WEE1 form a feedforward regulatory loop to promote mitotic entry. We further identified CUL1, CUL4A, DDB1, and SKP2 as components of E3 ubiquitin ligase complexes that mediate YTHDF2 proteolysis. Our study provides insights into how cell cycle mediators modulate transcriptomic m6A modification, which in turn regulates the cell cycle.
Project description:Dynamic N6-methyladenosine (m6A) modification was previously identified as a ubiquitous post-transcriptional regulation that affected mRNA homeostasis. However, the m6A-related epitranscriptomic alterations and functions remain elusive in human diseases such as cancer. Here we show that hypoxia regulates the ‘reader’ protein YTH domain family 2 (YTHDF2), to eventually stabilize the methylated oncogene mRNAs in inflammation-associated liver cancer. YTHDF2 silenced in human cancer cells or depleted in mouse hepatocytes evoked pro-inflammatory responses and accelerated tumor growth and metastatic progression. Under hypoxia, YTHDF2 processed the decay of m6A-containing interleukin 11 (IL11) and serpin family E member 2 (SERPINE2) mRNAs, which were responsible for the inflammation-mediated malignancy. Reciprocally, YTHDF2 transcription succumbed to hypoxia-inducible factor-2α (HIF-2α). Administration of a HIF-2α antagonist (PT2385) restored YTHDF2-programed epigenetic machinery and repressed liver cancer. Hence, our findings provide a new insight into the mechanism by which hypoxia adapts m6A-mRNA editing to promote cancer.
Project description:N6-methyladenosine (m6A) is the most prevalent post-transcriptional modification on RNA. NK cells are the predominant innate lymphoid cells that mediate anti-viral and anti-tumor immunity. However, whether and how m6A modifications affect NK cell immunity remains unknown. Here, we discover that YTHDF2, a well-known m6A reader, is upregulated in NK cells upon activation by cytokines, tumors, and cytomegalovirus infection. Ythdf2 deficiency in NK cells impairs NK cell anti-tumor and anti-viral activity in vivo. YTHDF2 maintains NK cell homeostasis and terminal maturation, correlating with modulating NK cell trafficking and regulating Eomes, respectively. YTHDF2 promotes NK cell effector function and is required for IL-15-mediated NK cell survival and proliferation by forming a STAT5-YTHDF2 positive feedback loop. Transcriptome-wide screening identifies Tardbp to be involved in cell proliferation or survival as a YTHDF2-binding target in NK cells. Collectively, we elucidate the biological roles of m6A modifications in NK cells and highlight a new direction to harness NK cell anti-tumor immunity.
Project description:The mRNA m6A reader YTHDF2 is overexpressed in a broad spectrum of human acute myeloid leukemias (AML). To understand the role of YTHDF2 in AML, we generated m6A meRIP-seq libraries form Ythdf2fl/fl (Ythdf2CTL) pre-leukemic cells.