Project description:RIP-chip analysis to identify mRNA preferentially associated with Msi1 protein. RIP-Chip experiments were performed on two biologically replicated samples transfected with the BAP-Msi1 construct and a control sample from cells transfected with the BAP-Control construct. A total of 8 microarrays were carried on using technical replicates of BAP-Msi1 vs. BAP-Control for each dye orientation.
Project description:Musashi1 (Msi1) is a highly conserved RNA binding protein that is required during the development of the nervous system. Msi1 has a role in neural stem cells, controlling the balance between self-renewal and differentiation. Msi1 has also been implicated in cancer, being highly expressed in multiple tumor types. In this study, we analyzed Msi1 expression in a large cohort of medulloblastoma samples and showed that Msi1 is highly expressed in tumor tissue compared to normal cerebellum and that high Msi1 expression is associated with a poor prognosis. Using a nude mouse xenograft model, we demonstrate that Msi1 is important for tumor growth. We then used RIP-chip (ribonucleoprotein immunoprecipitation followed by microarray analysis) to identify mRNA targets of Msi1 in medulloblastoma. In conclusion, our results suggest that Msi1 functions as a regulator of multiple processes in medulloblastoma formation and could become an important therapeutic target. RIP-Chip analysis to identify mRNA preferentially associated with Msi1 protein. RIP-Chip experiments were performed on two biologically replicated samples. A total of 8 microarrays were carried on using technical replicates of Msi1 antibody vs. prebleed serum for each dye orientation. We prepared two biological replicates for two different arrays. Each array consisted of 4 microarrays with 2 replicates for each dye orientation.
Project description:Musashi1 (Msi1) is a highly conserved RNA binding protein that is required during the development of the nervous system. Msi1 has a role in neural stem cells, controlling the balance between self-renewal and differentiation. Msi1 has also been implicated in cancer, being highly expressed in multiple tumor types. In this study, we analyzed Msi1 expression in a large cohort of medulloblastoma samples and showed that Msi1 is highly expressed in tumor tissue compared to normal cerebellum and that high Msi1 expression is associated with a poor prognosis. Using a nude mouse xenograft model, we demonstrate that Msi1 is important for tumor growth. We then used RIP-chip (ribonucleoprotein immunoprecipitation followed by microarray analysis) to identify mRNA targets of Msi1 in medulloblastoma. In conclusion, our results suggest that Msi1 functions as a regulator of multiple processes in medulloblastoma formation and could become an important therapeutic target.
Project description:The translational reactivation of maternal mRNAs encoding the drivers of vertebrate meiosis is accomplished mainly by cytoplasmic polyadenylation. The Cytoplasmic Polyadenylation Elements (CPEs) present in the 3’ UTR of these transcripts, together with their cognate CPE-binding proteins (CPEBs), define a combinatorial code that determines the timing and extent of translational activation upon meiosis resumption. In addition, the RNA-binding protein Musashi1 (Msi1) regulates the polyadenylation of CPE-containing mRNAs by an as yet undefined CPEB-dependent or -independent mechanism. Here we show that Msi1 alone does not support cytoplasmic polyadenylation, but its binding triggers the remodeling of RNA structure, thereby exposing adjacent CPEs and stimulating polyadenylation. Thus, Msi1 directs the preferential use of specific CPEs, which in turn affects the timing and extent of polyadenylation during meiotic progression. Genome-wide analysis of CPEB1- and Msi-associated mRNAs identified 491 common targets, thus revealing a new layer of CPE-mediated translational control.
Project description:The translational reactivation of maternal mRNAs encoding the drivers of vertebrate meiosis is accomplished mainly by cytoplasmic polyadenylation. The Cytoplasmic Polyadenylation Elements (CPEs) present in the 3’ UTR of these transcripts, together with their cognate CPE-binding proteins (CPEBs), define a combinatorial code that determines the timing and extent of translational activation upon meiosis resumption. In addition, the RNA-binding protein Musashi1 (Msi1) regulates the polyadenylation of CPE-containing mRNAs by an as yet undefined CPEB-dependent or -independent mechanism. Here we show that Msi1 alone does not support cytoplasmic polyadenylation, but its binding triggers the remodeling of RNA structure, thereby exposing adjacent CPEs and stimulating polyadenylation. Thus, Msi1 directs the preferential use of specific CPEs, which in turn affects the timing and extent of polyadenylation during meiotic progression. Genome-wide analysis of CPEB1- and Msi-associated mRNAs identified 491 common targets, thus revealing a new layer of CPE-mediated translational control.
Project description:The translational reactivation of maternal mRNAs encoding the drivers of vertebrate meiosis is accomplished mainly by cytoplasmic polyadenylation. The Cytoplasmic Polyadenylation Elements (CPEs) present in the 3’ UTR of these transcripts, together with their cognate CPE-binding proteins (CPEBs), define a combinatorial code that determines the timing and extent of translational activation upon meiosis resumption. In addition, the RNA-binding protein Musashi1 (Msi1) regulates the polyadenylation of CPE-containing mRNAs by an as yet undefined CPEB-dependent or -independent mechanism. Here we show that Msi1 alone does not support cytoplasmic polyadenylation, but its binding triggers the remodeling of RNA structure, thereby exposing adjacent CPEs and stimulating polyadenylation. Thus, Msi1 directs the preferential use of specific CPEs, which in turn affects the timing and extent of polyadenylation during meiotic progression. Genome-wide analysis of CPEB1- and Msi-associated mRNAs identified 491 common targets, thus revealing a new layer of CPE-mediated translational control.
Project description:RIP-Chip analysis of PCBP2 and identification of preferentially associated mRNAs. T98G cells were transfected transiently with BAP-tagged constructs. BAP-tagged proteins were biotinylated in vivo by the co-transfected hBirA enzyme. RNPs were recovered via precipitation with Steptavidin-sepharose beads. Finally, RNAs were purified and analyzed on microarrays. BAP-GFP as control was used in three independent sets of experiments.
Project description:RIP-Chip analysis of PCBP2 and identification of preferentially associated mRNAs. T98G cells were transfected transiently with BAP-tagged constructs. BAP-tagged proteins were biotinylated in vivo by the co-transfected hBirA enzyme. RNPs were recovered via precipitation with Steptavidin-sepharose beads. Finally, RNAs were purified and analyzed on microarrays. BAP-GFP as control was used in three independent sets of experiments. Two-condition experiment, BAP-PCBP2 vs. BAP-GFP cells. Biological replicates: 3 BAP-PCBP2 replicates, 3 BAP-GFP (Control) replicates
Project description:To understand the function of MSI1 in pluripotent stem cells, RNA-seq assays were performed on mouse embryonic stem cells R1, MSI1 knockout cell line R1-C5, human embryonic stem cells H9, RRM knockout cell line H9-C8, MSI1 full-length overexpression cell line H9-MSI1OE, MSI1C variant overexpression cell line H9-MSI1 (138-362) OE , H9-MSI1(272-362)OE. RNA bound by MSI1 in R1 and H9, and MSI1C variants MSI1 (138-362), MSI1(272-362) were detected using RIP-seq.