Project description:Sox2 has been studied in several types of human solid tumors. The investigators found that Sox2 had higher expression level in colorectal cancer and metastatic tissues than normal tissues. So the investigators assumed that whether Sox2 plays an important role in the progression and migration of colon cancer.
Project description:The pluripotency transcription factor SOX2 is essential for the maintenance of glioblastoma stem cells (GSC), which drive tumor growth and treatment resistance.To understand how SOX2 is regulated in GSCs, we utilized a proteomic approach and identified the E3 ubiquitin ligase TRIM26 as a direct SOX2-interacting protein. Unexpectedly, we found TRIM26 depletion decreased SOX2 protein levels and increased SOX2 polyubiquitination in patient-derived GSCs, suggesting TRIM26 promotes SOX2 protein stability. Accordingly, TRIM26 knockdown reduced SOX2 transcriptional activity, self-renewal capacity, and in vivo tumorigenicity in multiple GSC lines. Mechanistically, we found TRIM26, via its C-terminal PRYSPRY domain, but independent of its RING domain, stabilizes SOX2 protein by directly inhibiting the interaction of SOX2 with WWP2, which we identify as a bona fide SOX2 E3 ligase in GSCs. Our work identifies E3 ligase competition as a critical mechanism of SOX2 regulation, with functional consequences for GSC identity and maintenance.
Project description:Purpose: Sox2 expression marks gastric stem and progenitor cells, raising important questions regarding the genes regulated by Sox2 and the role of Sox2 itself during stomach homeostasis and disease. The goal of this study is to determine the function of and the genes regulated by Sox2 in the stomach. Methods: Sox2 ChIP-enriched DNA and input DNA was isolated from gastric glands of adult antrum from Sox2 KO and Sox2 WT mice. DNA was purified and genomic libraries were prepared as described (Sulahian et al., 2014), using four micrograms of goat anti-SOX2 (AF2018, R&D). Libraries were sequenced (50 bp, single-end reads) on an Illumina Hi-Seq 2000 instrument. Results: Sox2 is dispensiable for gastric stem cell self-renewal and epithelial homeostasis, however modulates the expression of wnt, intestinal and cancer related genes Examination of Sox2 targets in the stomachs of Sox2 WT and Sox2 KO mice.
Project description:Genome-wide transcriptional activity involves the binding of many transcription factors to thousands of sites in the genome. Determining which sites are directly driving transcription remains a challenge. Here we use acute protein depletion of the pioneer transcription factor SOX2 to establish its functionality in maintaining chromatin accessibility. We show that thousands of accessible sites are lost within an hour of protein depletion, indicating rapid turnover of these sites in the absence of pioneer factors. To understand the relationship with transcription we performed nascent transcription analysis and found that open chromatin sites that are maintained by SOX2 are highly predictive of gene expression, in contrast to all other SOX2 binding sites. We use CRISPR-Cas9 genome editing in the Klf2 locus to functionally validate a predicted regulatory element. We conclude that the regulatory activity of SOX2 is exerted largely at sites where it maintains accessibility and that other binding sites are largely dispensable for gene regulation.
Project description:Purpose: Sox2 expression marks gastric stem and progenitor cells, raising important questions regarding the genes regulated by Sox2 and the role of Sox2 itself during stomach homeostasis and disease. The goal of this study is to determine the function of and the genes regulated by Sox2 in the stomach. Methods: Sox2 ChIP-enriched DNA and input DNA was isolated from gastric glands of adult antrum from Sox2 KO and Sox2 WT mice. DNA was purified and genomic libraries were prepared as described (Sulahian et al., 2014), using four micrograms of goat anti-SOX2 (AF2018, R&D). Libraries were sequenced (50 bp, single-end reads) on an Illumina Hi-Seq 2000 instrument. Results: Sox2 is dispensiable for gastric stem cell self-renewal and epithelial homeostasis, however modulates the expression of wnt, intestinal and cancer related genes
Project description:To mechanistically define the function of SOX2 in prostate cancer cells and how it contributes to therapeutic resistance, we performed paired SOX2 chromatin immunoprecipitation-sequencing (ChIP-Seq) and RNA-sequencing (RNA-Seq) on a SOX2-positive CRPC cell line, CWR-R1, to determine which genes SOX2 binds and potentially regulates. To identify novel prostate cancer-specific SOX2 gene targets in CRPC cells distinct from known SOX2 stem cell genes, we conducted parallel SOX2 ChIP-Seq and RNA-Seq in the WA01 embryonic stem cell line and compared results to identified SOX2 targets from CWR-R1 cells
Project description:As a test for the effectiveness of SPIDER with RNA-protein pairs, We used Sox2 and specific biotin-DNA and biotin-RNA to validate the efficiency of SPIDER capturing protein-nucleic acid interaction. Pupylation sites on Sox2 after SPIDER assay was identified by LC-MS/MS analysis, by searching for an additional mass of ~243 Da, which represents the three C-terminal residues of Pup, i. e., GGE, that covalently binds to adjacent lysine by pupylation. )
Project description:SOX2 is a transcription factor essential for pluripotent stem cells, and development and maintenance of squamous epithelium. We previously reported SOX2 an oncogene subject to highly recurrent genomic amplification in squamous cell carcinomas (SCCs). Here we demonstrate in SCCs that SOX2 interacts with another master squamous transcription factor p63, and through ChIP-seq show that genomic occupancy of SOX2 overlaps with that of p63 at a large number of loci and that they cooperatively regulate gene expression including ETV4, which we find essential for SOX2-amplified SCC cell survival. Furthermore, SOX2 binds to distinct genomic loci in SCCs than in embryonic stem cells and the SOX2-p63 coordinate binding is unique to SCC. In addition, a subset of SOX2 genomic binding sites in SCC that lack p63 co-occupancy are co-occupied by the AP-1 transcriptional complex. These demonstrate that SOX2’s actions in SCC differ substantially from its role in pluripotency and identify novel SOX2 interactions that will enable deeper characterization of SOX2’s function in SCC. SOX2 and p63 ChIP-seq from three lung and esophageal squamous carcinoma cell lines with amplification of SOX2 as well as SOX2 ChIP-seq from an ES cells.
Project description:We report that knockdown of the lncRNA RMST changes the chromatin binding profile of the transcription factor SOX2. Examination of SOX2 chromatin binding profile under normal and RMST-depleted conditions in differentiating neural stem cells.