Project description:iCLIP was performed for FLAG-tagged MSI2 in K562 cells. Polysome profiling was performed for MSI2-knockdown and control shRNA K562 cells
Project description:The Musashi-2 (Msi2) RNA-binding protein maintains stem cell self-renewal and promotes oncogenesis by enhancing cell proliferation in hematopoietic and gastrointestinal tissues. However, it is unclear how Msi2 recognizes and regulates mRNA targets in vivo and whether Msi2 primarily controls cell growth in all cell types. Here we identified Msi2 targets with HITSCLIP and revealed that Msi2 primarily recognizes mRNA 3UTRs at sites enriched in multiple copies of UAG motifs in epithelial progenitor cells. RNA-seq and ribosome profiling demonstrated that Msi2 promotes targeted mRNA decay without affecting translation efficiency. Unexpectedly, the most prominent Msi2 targets identified are key regulators that govern cell motility with a high enrichment in focal adhesion and extracellular matrix-receptor interaction, in addition to regulators of cell growth and survival. Loss of Msi2 stimulates epithelial cellmigration, increases the number of focal adhesion and also compromises cell growth. These findings provide new insights into the molecular mechanisms of Msi2âs recognition and repression of targets and uncover a key function of Msi2 in restricting epithelial cell migration. Identification of direct Musashi-2 targets in keratinocytes through the use of RNA-Seq, Ribosome-Profiling, and Msi2-HITS-CLIP
Project description:The Musashi-2 (Msi2) RNA-binding protein maintains stem cell self-renewal and promotes oncogenesis by enhancing cell proliferation in hematopoietic and gastrointestinal tissues. However, it is unclear how Msi2 recognizes and regulates mRNA targets in vivo and whether Msi2 primarily controls cell growth in all cell types. Here we identified Msi2 targets with HITSCLIP and revealed that Msi2 primarily recognizes mRNA 3UTRs at sites enriched in multiple copies of UAG motifs in epithelial progenitor cells. RNA-seq and ribosome profiling demonstrated that Msi2 promotes targeted mRNA decay without affecting translation efficiency. Unexpectedly, the most prominent Msi2 targets identified are key regulators that govern cell motility with a high enrichment in focal adhesion and extracellular matrix-receptor interaction, in addition to regulators of cell growth and survival. Loss of Msi2 stimulates epithelial cellmigration, increases the number of focal adhesion and also compromises cell growth. These findings provide new insights into the molecular mechanisms of Msi2’s recognition and repression of targets and uncover a key function of Msi2 in restricting epithelial cell migration.
Project description:Hematopoietic stem cells (HSCs) are maintained through the regulation of symmetric and asymmetric cell division. We report that conditional ablation of the RNA-binding protein Msi2 results in a failure of HSC maintenance and engraftment caused by a loss of quiescence and increased commitment divisions. Contrary to previous studies, we found that these phenotypes were independent of Numb. Global transcriptome profiling and RNA target analysis uncovered Msi2 interactions at multiple nodes within pathways that govern RNA translation, stem cell function, and TGF-β-signaling. Msi2-null HSCs are insensitive to TGF-β–mediated expansion and have decreased signaling output, resulting in a loss of myeloid-restricted HSCs and myeloid reconstitution. Thus, Msi2 is an important regulator of the HSC translatome and balances HSC homeostasis and lineage bias. One empty vector control– and two Flag-MSI2–overexpressing K562 cell samples were analyzed using HITS-CLIP protocol
Project description:mRNA-seq and ribosome profiling of neural stem cells overexpressing or knocked out for Musashi RNA-binding proteins Study of the global effects of Musashi (Msi) proteins on the transcriptome of embryonic neural stem cells. Neural stem cells were derived from brains of E12.5 or E13.5 embryos engineered to have inducible Msi1 or Msi2 genes, or from embryos with double floxed alleles of Msi1 and Msi2 carrying a Tamoxifen-induclble Cre (CreER). The overexpression mice were made using the Flp-in system (OpenBioSystems), where a cDNA of interest (in this case Msi1 or Msi2) is knocked into the Collagen (Col1A1) locus. The expression of the cDNA of interest is driven by m2rTTA that is knocked into the Rosa26 locus (R26). KH2 describes a strain containing the R26-m2rTTA but lacking Msi1 or Msi2 cDNA. MSI1 describes a strain containing R26-m2rTTA and Msi1 cDNA in Col1A1. MSI2 describes a strain containing R26-m2rTTA and Msi2 cDNA in Col1A1. C1 describes a strain lacking the CreER allele but containing double floxed alleles of Msi1/Msi2 (used as Tamoxifen control). C4 describes a strain carrying the CreER allele and double floxed alleles of Msi1/Msi2.
Project description:Recent studies have shown that the RNA binding protein Musashi 2 (Msi2) plays prominent roles during development and leukemia. Additionally, in embryonic stem cells (ESC) undergoing the early stages of differentiation, Msi2 has been shown to associate with Sox2, which is required for the self-renewal of ESC. These findings led us to examine the effects of Msi2 on the behavior of ESC. Using an shRNA sequence that targets Msi2 and a scrambled shRNA sequence, we determined that knockdown of Msi2 disrupts the self-renewal of ESC and promotes their differentiation. Collectively, our findings argue that Msi2 is required to support the self-renewal and pluripotency of ESC. We used microarrays to better understand global changes in ESC gene expression following the knockdown of the RNA-binding protein Msi2 as compared to control ESC expressing a scrambled shRNA.
Project description:This SuperSeries is composed of the following subset Series: GSE16432: MSI2 regulates hematopoiesis and accelerates leukemogenesis GSE22773: Musashi 2 regulates normal hematopoiesis and accelerates leukemogenesis (LK and MS12-inducible) GSE22774: Musashi 2 regulates normal hematopoiesis and accelerates leukemogenesis (LSK and LK) GSE22775: Musashi 2 regulates normal hematopoiesis and accelerates leukemogenesis (Leukemia cell lines) Refer to individual Series
Project description:Recent studies have shown that the RNA binding protein Musashi 2 (Msi2) plays prominent roles during development and leukemia. Additionally, in embryonic stem cells (ESC) undergoing the early stages of differentiation, Msi2 has been shown to associate with Sox2, which is required for the self-renewal of ESC. These findings led us to examine the effects of Msi2 on the behavior of ESC. Using an shRNA sequence that targets Msi2 and a scrambled shRNA sequence, we determined that knockdown of Msi2 disrupts the self-renewal of ESC and promotes their differentiation. Collectively, our findings argue that Msi2 is required to support the self-renewal and pluripotency of ESC. We used microarrays to better understand global changes in ESC gene expression following the knockdown of the RNA-binding protein Msi2 as compared to control ESC expressing a scrambled shRNA. Mouse embryonic stem cells (D3) were treated with lentivirus engineered for the expression of a Msi2 targeting shRNA sequence or scrambled (control) shRNA sequence. Following selection for infected cells with puromycin, cells were subcultured at low density and allowed to grow for 4 days (see treatment protocol) before RNA was extracted. RNA was collected and analyzed one time for each of the two samples.
Project description:We examined the possible effects of hypertonic stress on Arabidopsis translatome using polysome profiling. We found that the translatome is partly and rapidly reprogrammed in response to hypertonic stress, and such translatome reprogramming is DCP5-dependent.
Project description:We show that the RNA-binding protein CSDE1/UNR promotes oncogene-induced senescence (OIS) in primary mouse keratynocytes challenged by over-expression of H-RASv12. Depletion of CSDE1 leads to senescence bypass, cell immortalization and tumor formation. Combining individual nucleotide cross-linking and immunoprecipitation (iCLIP), RNA-seq and polysome profiling followed by functional studies, we identify targets regulated by CSDE1 and uncover the downstream molecular mechanisms.