Project description:TGF-β-SMAD signaling pathway plays an important role in progression of various tumors. However, posttranscriptional regulation such as N6-methyladenosine (m6A) of TGF-β-SMAD signaling axis remains incompletely understood. Here, we reveal that Insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) is low expression as well as associated with poor prognosis in clear cell renal cell carcinoma (ccRCC) patients and inhibits proliferation as well as promotes metastasis of ccRCC cells. To explore the underlying mechanism of IGF2BP2 in ccRCC, RNA-seq, RIP-seq and LACE-seq were performed to investigate the downstream targets of IGF2BP2.
Project description:TGF-β-SMAD signaling pathway plays an important role in progression of various tumors. However, posttranscriptional regulation such as N6-methyladenosine (m6A) of TGF-β-SMAD signaling axis remains incompletely understood. Here, we reveal that Insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) is low expression as well as associated with poor prognosis in clear cell renal cell carcinoma (ccRCC) patients and inhibits proliferation as well as promotes metastasis of ccRCC cells. To explore the underlying mechanism of IGF2BP2 in ccRCC, RNA-seq, RIP-seq and LACE-seq were performed to investigate the downstream targets of IGF2BP2.
Project description:TGF-β-SMAD signaling pathway plays an important role in progression of various tumors. However, posttranscriptional regulation such as N6-methyladenosine (m6A) of TGF-β-SMAD signaling axis remains incompletely understood. Here, we reveal that Insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) is low expression as well as associated with poor prognosis in clear cell renal cell carcinoma (ccRCC) patients and inhibits proliferation as well as promotes metastasis of ccRCC cells. To explore the underlying mechanism of IGF2BP2 in ccRCC, RNA-seq, RIP-seq and LACE-seq were performed to investigate the downstream targets of IGF2BP2.
Project description:We performed m6A-RIPs in Ascl1-induced neurons (iNeurons) to investigate the neuronal m6A epitranscriptome. Immunoprecipitation was done twice using two different antibodies, acquired from Abcam and Synaptic Systems (SySy), allowing for a more robust detection of m6A modification marks. Additionally, RIP-seq was performed separately with intact and fragmented RNA. The former approach allowed to identify proportions of m6A-modified transcripts among the total number, while the latter approach provided the information to identify genomic coordinates of m6A peaks.
Project description:Cytokines of the TGF-β superfamily control essential cell fate decisions via receptor regulated SMAD (R-SMAD) transcription factors. Ligand-induced R-SMAD phosphorylation in the cytosol triggers their activation and nuclear accumulation. We determined how R-SMADs are inactivated by dephosphorylation in the cell nucleus to counteract signaling by TGF-β superfamily ligands. We showed that R-SMAD dephosphorylation is mediated by an inner nuclear membrane associated complex containing the scaffold protein MAN1 and the CTDNEP1/NEP1R1 phosphatase. Structural prediction, domain mapping and mutagenesis revealed that MAN1 binds independently to the CTDNEP1/NEP1R1 phosphatase and R-SMADs to promote their inactivation by dephosphorylation. Disruption of this complex led to nuclear accumulation of R-SMADs and aberrant signaling, even in the absence of TGF-β ligands. These findings establish CTDNEP1/NEP1R1 as the elusive R-SMAD phosphatase and reveal the mechanistic basis for TGF-β signaling inactivation and how this process is disrupted by disease-associated MAN1 mutations.
Project description:TGF-β is involved in various biological processes, including development, differentiation, growth regulation, and epithelial-mesenchymal transition (EMT). In TGF-β/Smad signaling, receptor-activated Smad complexes activate or repress their target gene promoters. Smad cofactors are a group of Smad-binding proteins that promote recruitment of Smad complexes to these promoters. Long noncoding RNAs (lncRNAs), that behave as Smad cofactors have thus far not been identified. Here, we characterize a novel lncRNA EMT-associated lncRNA induced by TGF-β-1(ELIT-1). ELIT-1 was induced by TGF-β-stimulation via the TGF-β/Smad pathway in TGF-β-responsive cell lines. ELIT-1-depletion abrogated TGF-β-mediated EMT progression and expression of TGF-β target genes including Snail, a transcription factor critical for EMT. A positive correlation between high expression of ELIT-1 and poor prognosis in lung adenocarcinoma and gastric cancer patients suggests that ELIT-1 may be useful as a prognostic and therapeutic target. RIP assays revealed that ELIT-1 bound to Smad3, but not Smad2. In conjunction with Smad3, ELIT-1 enhanced Smad-responsive promoter activities by recruiting Smad3 to the promoters of its target genes including Snail, other TGF-β-target genes, and ELIT-1 itself. Collectively, these data show that ELIT-1 is a novel trans-acting lncRNA that forms a positive feedback loop to enhance TGF-β/Smad3 signaling and promote EMT progression.
Project description:TGF-β is involved in various biological processes, including development, differentiation, growth regulation, and epithelial-mesenchymal transition (EMT). In TGF-β/Smad signaling, receptor-activated Smad complexes activate or repress their target gene promoters. Smad cofactors are a group of Smad-binding proteins that promote recruitment of Smad complexes to these promoters. Long noncoding RNAs (lncRNAs), that behave as Smad cofactors have thus far not been identified. Here, we characterize a novel lncRNA EMT-associated lncRNA induced by TGF-β-1(ELIT-1). ELIT-1 was induced by TGF-β-stimulation via the TGF-β/Smad pathway in TGF-β-responsive cell lines. ELIT-1-depletion abrogated TGF-β-mediated EMT progression and expression of TGF-β target genes including Snail, a transcription factor critical for EMT. A positive correlation between high expression of ELIT-1 and poor prognosis in lung adenocarcinoma and gastric cancer patients suggests that ELIT-1 may be useful as a prognostic and therapeutic target. RIP assays revealed that ELIT-1 bound to Smad3, but not Smad2. In conjunction with Smad3, ELIT-1 enhanced Smad-responsive promoter activities by recruiting Smad3 to the promoters of its target genes including Snail, other TGF-β-target genes, and ELIT-1 itself. Collectively, these data show that ELIT-1 is a novel trans-acting lncRNA that forms a positive feedback loop to enhance TGF-β/Smad3 signaling and promote EMT progression.
Project description:The non-receptor tyrosine kinase SRC is upregulated in various human cancers and plays crucial roles in cancer progression by promoting invasion and metastasis. We show that the transforming growth factor beta (TGF-β/SMAD pathway directly upregulates SRC during the epithelial-mesenchymal transition. In human epithelial MCF10A cells, TGF-β1 treatment markedly upregulated mRNA expression of SRC. Knockout of SMAD4 suppressed upregulation of SRC by TGF-β1. ChIP-sequencing analysis revealed that SRC was transcribed from the SRC1A promoter, which interacted with SMAD2 and SMAD4, in response to TGF-β1. These findings demonstrate that a direct interaction of the activated SMAD complex with the SRC1A promoter directly upregulates SRC and suggest that TGF-β contributes to SRC upregulation in the tumor microenvironment, where TGF-β-mediated tumor progression takes place.