Project description:Progenitor/stem cell populations of the aorta have been poorly characterized and their self-renewal factors unknown. In this report, we demonstrate that sphere forming progenitor/stem cells, here within termed aortic neurospheres (ANS), can be cultivated from the aorta that are similar to skin-derived precursors (SKPs). Extensive mRNA transcript profiling revealed that ANS abundantly expressed the Inhibin βA transcript, of which the secreted protein dominantly formed the Inhibin βA-βA complex, or Activin A, in the proliferation medium. Co-localization of Activin A, Nestin and Sox2 was observed in the adventitial and peri-adventitial regions of the aorta, indicative of a progenitor/stem cell niche in vivo. Blockade of Activin A signaling, through the neutralization of the Type II Activin receptors ActRIIA and ActRIIB, resulted in the asymmetric differentiation, and epithelial-to-mesenchymal transition of the ANS, respectively. When treated with the latter neutralizing antibody, translocation of the ActRIIB receptor to the nucleus was observed in cells on the periphery of the sphere. Examination of the ActRIIB protein sequence showed the presence of a putative nuclear localization signal of the PY family that was conserved across species. The results from this study demonstrate that Activin A is a self-renewal factor required for maintaining ANS progenitor/stem cell identity and multipotency.
Project description:Progenitor/stem cell populations of the aorta have been poorly characterized and their self-renewal factors unknown. In this report, we demonstrate that sphere forming progenitor/stem cells, here within termed aortic neurospheres (ANS), can be cultivated from the aorta that are similar to skin-derived precursors (SKPs). Extensive mRNA transcript profiling revealed that ANS abundantly expressed the Inhibin βA transcript, of which the secreted protein dominantly formed the Inhibin βA-βA complex, or Activin A, in the proliferation medium. Co-localization of Activin A, Nestin and Sox2 was observed in the adventitial and peri-adventitial regions of the aorta, indicative of a progenitor/stem cell niche in vivo. Blockade of Activin A signaling, through the neutralization of the Type II Activin receptors ActRIIA and ActRIIB, resulted in the asymmetric differentiation, and epithelial-to-mesenchymal transition of the ANS, respectively. When treated with the latter neutralizing antibody, translocation of the ActRIIB receptor to the nucleus was observed in cells on the periphery of the sphere. Examination of the ActRIIB protein sequence showed the presence of a putative nuclear localization signal of the PY family that was conserved across species. The results from this study demonstrate that Activin A is a self-renewal factor required for maintaining ANS progenitor/stem cell identity and multipotency.
Project description:Other than in the development of the brain, SOX2 is essential for the long-term self-renewal of neural stem cells (NSCs). The mechanisms of how SOX2 maintains the stemness of NSCs is not yet understood. We have identified Fos as a downstream target of SOX2, and therefore used CUT&RUN to investigate where these transcription factors - and the c-FOS partner c-JUN - interact with the genome. By comparing binding patterns of c-FOS, c-JUN and SOX2, we find that they co-occupate the promoter of the SOCS3 locus, which we also have identified as a gene that rescues SOX2 deletion induced senescence when overexpressed in neurospheres grown from Sox2-deleted mouse NSCs. Taken together, our data provide a basis for elucidating a gene regulatory network necessary for the maintenance of self-renewal in post-embryonic neural stem cells.
Project description:Progenitor/stem cell populations of the aorta have been poorly characterized and their self-renewal factors unknown. In this report, we demonstrate that sphere forming progenitor/stem cells, here within termed aortic neurospheres (ANS), can be cultivated from the aorta that are similar to skin-derived precursors (SKPs). Extensive mRNA transcript profiling revealed that ANS abundantly expressed the Inhibin βA transcript, of which the secreted protein dominantly formed the Inhibin βA-βA complex, or Activin A, in the proliferation medium. Co-localization of Activin A, Nestin and Sox2 was observed in the adventitial and peri-adventitial regions of the aorta, indicative of a progenitor/stem cell niche in vivo. Blockade of Activin A signaling, through the neutralization of the Type II Activin receptors ActRIIA and ActRIIB, resulted in the asymmetric differentiation, and epithelial-to-mesenchymal transition of the ANS, respectively. When treated with the latter neutralizing antibody, translocation of the ActRIIB receptor to the nucleus was observed in cells on the periphery of the sphere. Examination of the ActRIIB protein sequence showed the presence of a putative nuclear localization signal of the PY family that was conserved across species. The results from this study demonstrate that Activin A is a self-renewal factor required for maintaining ANS progenitor/stem cell identity and multipotency.
Project description:SXO2 is one of the factors involved in maintaining self-renewal and pluripotency in hESCs. This study was performed to reveal the effects of reduced SOX2 levels in self-renewing pluripotent hESCs.
Project description:The ganglionic eminence was dissected and neurospheres were cultured from the brain of E13.5 embroys. RNA was isolated from neurospheres cultured from p107-/- embryos and their wildtype littermates. P107 knockout mice have previously been shown to have an increased number of stem cells and enhanced stem cell self renewal. With the microarray experiment we are hoping to discover the genes involved in stem cell number and self renewal along with p107. Keywords: other
Project description:An immortalized multipotent otic progenitor (iMOP) cell was generated by transient expression of c-Myc in Sox2-expressing otic progenitor cells. The procedure activated endogenous c-Myc expression in the cells and amplified existing Sox2-dependent transcripts to promote self-renewal. Downregulation of c-Myc expression following growth factor withdrawal resulted in a molecular switch from self-renewal to otic differentiation. ChIP-Seq was accomplished by immunoprecipitating endogenous RNA PolII, c-Myc and Sox2