Project description:The intermediate filament protein Nestin serves as a biomarker for stem cells and has been used to identify subsets of cancer stem-like cells. However, the mechanistic contributions of Nestin to cancer pathogenesis are not understood. Here we report that Nestin binds the hedgehog pathway transcription factor Gli3 to mediate the development of medulloblastomas of the hedgehog subtype. In a mouse model system, Nestin levels increased progressively during medulloblastoma formation resulting in enhanced tumor growth. Conversely, loss of Nestin dramatically inhibited proliferation and promoted differentiation. Mechanistic investigations revealed that the tumor-promoting effects of Nestin were mediated by binding to Gli3, a zinc finger transcription factor that negatively regulates hedgehog signaling. Nestin binding to Gli3 blocked Gli3 phosphorylation and its subsequent proteolytic processing, thereby abrogating its ability to negatively regulate the hedgehog pathway. Our findings show how Nestin drives hedgehog pathway-driven cancers and uncover in Gli3 a therapeutic target to treat these malignancies.
Project description:During in vitro differentiation, pluripotent stem cells undergo extensive remodeling of their gene expression profiles. While studied extensively at the transcriptome level, much less is known about protein dynamics, which might differ significantly from their mRNA counterparts. Here, we present deep proteome-wide measurements of protein levels during the differentiation of embryonic stem cells.
Project description:The intermediate filament protein Nestin serves as a biomarker for stem cells and has been used to identify subsets of cancer stem-like cells. However, the mechanistic contributions of Nestin to cancer pathogenesis are not understood. Here we report that Nestin binds the hedgehog pathway transcription factor Gli3 to mediate the development of medulloblastomas of the hedgehog subtype. In a mouse model system, Nestin levels increased progressively during medulloblastoma formation resulting in enhanced tumor growth. Conversely, loss of Nestin dramatically inhibited proliferation and promoted differentiation. Mechanistic investigations revealed that the tumor-promoting effects of Nestin were mediated by binding to Gli3, a zinc finger transcription factor that negatively regulates hedgehog signaling. Nestin binding to Gli3 blocked Gli3 phosphorylation and its subsequent proteolytic processing, thereby abrogating its ability to negatively regulate the hedgehog pathway. Our findings show how Nestin drives hedgehog pathway-driven cancers and uncover in Gli3 a therapeutic target to treat these malignancies. Nestin+ and Nestin- GNPs (granule neuron precursors) were purified from Nestin-CFP/Math1-Cre/Ptch1-loxp cerebella at postnatal day 4 by FACs, and total RNA from these two cell populations were extracted, and then labeled and hybridized to Affymetrix Mouse Genome 430 2.0 arrays.
Project description:Raw .d files containing LC-DTIMS-CID-MS for the analysis of lipidomic changes during stem cell differentiation into mesodermal and neural cell lineages.
Project description:Identification of product of proteolysis during C2C12 myoblast differentiation using subtiligase N-terminomics. Different cell populations collected during a time-course of differentiation (4 days) were used for N-terminal labeling in a forward degradomics approach (n=2). Day0 population= Myoblasts, Day1 populations= live cells and dead cells, Day4 populations= Myotubes and Reserve cells. Additionally, cleavages events generated by mouse caspase-3 at early stages of differentiation (Day 0 and 1) was evaluated using a reverse degradomics approach on myoblasts and live cells (n=2).
Project description:Here we study genome architecture in a postmitotic differentiation setting, the differentiation of human blood monocytes (MO). We profiled and compared epigenetic, transcriptome and 3D conformation landscapes during MO differentiation (either into dendritic cells or macrophages) across the genome, with and without siRNA-mediated depletion of RD21 or CTCF, and detected numerous architectural changes, ranging from higher level compartments