Project description:A small number of transcription factors, including Oct-3/4 and Sox2, constitute the transcriptional network that maintains pluripotency in embryonic stem (ES) cells. Previous reports suggested that some of these factors form a complex that binds the Oct-Sox element, a composite sequence consisting of closely juxtaposed Oct-3/4-binding and Sox2-binding sites. However, little is known regarding the components of the complex. In this study, we show that Sall4, a member of the Spalt-like family of proteins, directly interacts with Sox2 and Oct-3/4. Sall4 in combination with Sox2 or Oct-3/4 simultaneously occupies the Oct-Sox elements in mouse ES cells. Sall4 knockdown led to differentiation of ES cells. Overexpression of Sall4 in ES cells increased reporter activities in a luciferase assay when the Pou5f1- or Nanog-derived Oct-Sox element was included in the reporter. Microarray analyses revealed that Sall4 and Sox2 bound to the same genes in ES cells significantly more frequently than expected from random coincidence. These factors appeared to bind the promoter regions of a subset of the Sall4- and Sox2-double-positive genes in precisely similar distribution patterns along the promoter regions, suggesting that Sall4 and Sox2 associate with such Sall4/Sox2-overlapping genes as a complex. Importantly, gene ontology analyses indicated that the Sall4/Sox2-overlapping gene set is enriched for genes involved in maintaining pluripotency. Sall4/Sox2/Oct-3/4-triple-positive genes identified by referring to a previous study identifying Oct-3/4-bound genes in ES cells were further enriched for pluripotency genes than Sall4/Sox2-double-positive genes. These results demonstrate that Sall4 contributes to the transcriptional network operating in pluripotent cells, together with Oct-3/4 and Sox2.
Project description:Purpose: In this work, we evaluated the role of two indicative species, Citrobacter werkmanii (CW) and Escherichia albertii (EA), in the virulence of two DEC pathotypes, Shiga toxin-producing (STEC) and enteroaggregative (EAEC) Escherichia coli. Methods: To determine the effect of supernatant obtained from CW and EA cultures in STEC strain 86-24 and EAEC strain 042 gene expression, a RNA-seq analysis was performed. T84 cells were infected with DEC strains in the presence or absence of supernatant from EA and IL-8 secretion was evaluated. The effect of supernatant from EA on the growth and adherence of STEC and EAEC to T84 cells was also evaluated. Finally, we studied the participation of long polar fimbriae (Lpf) in STEC and plasmid-encoded toxin (Pet) in EAEC during DEC infection in the presence of supernatant from EA. Results: RNA-seq analysis revealed that several virulence factors in STEC and EAEC were up-regulated in the presence of supernatants from CW and EA. Interestingly, an increase in the secretion of IL-8 was observed in T84 cells infected with STEC or EAEC in the presence of a supernatant from EA. Similar results were observed with the supernatants obtained from clinical strains of E. albertii. Supernatant from EA had no effect on the growth of STEC and EAEC, or on the ability of these DEC strains to adhere to intestinal epithelial cells. Finally, we found that Pet toxin in EAEC was up-regulated in the presence of a supernatant from EA. In STEC, using mutant strains for Lpf fimbriae, our data suggested that these fimbriae might be participating in the increase of IL-8 induced by STEC on intestinal epithelial cells in the presence of a supernatant from EA. Conclusion:Supernatant obtained from an indicative species of DEC-positive diarrhea could modulate gene expression in STEC and EAEC, and IL-8 secretion induced by these bacteria. These data provide new insights into the effect of gut microbiota species in the pathogenicity of STEC and EAEC.
Project description:Hepatocellular carcinoma (HCC) is a malignant tumor with a high fatality rate, characterized by a poor prognosis and a low 5-year survival rate. Although significant progress has been made in immunotherapy and targeted therapy for HCC in recent years, the overall survival benefits for patients remain very limited. Therefore, the continuous development of new targets and the screening of specific therapeutic drugs are of great significance for further developing precise treatment methods, exploring more effective combination therapies, overcoming drug resistance. In our preliminary work 272 bioactive compounds have been isolated and identified from edible and medicinal traditional Chinese medicines including Lonicera japonica, Cistanche deserticola and Artemisia capillaris. Through systematic screening, we discovered that 16'-decarbomethoxydihydrovoacamine (16'-DEC), which derived from Tabernaemontana corymbosa, can significantly inhibit hepatoma cell viability and migratory capacity. Furthermore, 16'-DEC can act in combination with lenvatinib, an approved targeted drug for HCC, to further inhibit the proliferation of hepatoma cells in vitro and in vivo. Through transcriptome sequencing, we found that 16'-DEC significantly upregulated the autophagy-related signaling pathway. Mechanism studies have validated that 16'-DEC does induce autophagy in hepatoma cells, and blocking autophagy can significantly reverse the anti-tumor activity of 16'-DEC. Furthermore, we found that 16'-DEC inhibited the activation of the mTOR signaling pathway, and molecular docking experiments indicated that 16'-DEC had a high affinity for the mTOR protein. Biochemical kinase assays confirmed 16'-DEC as a direct mTOR inhibitor, suppressing its kinase activity with an IC50 0.83 μM in cell-free systems. Taken together, these results demenstated that 16’-DEC inhibited hepatocellular carcinoma through inducing autophagy by targeting the mTOR pathway, which make it a potential therapeutic agent for HCC.
Project description:Genome-wide DNA methylation profiling of human B-ALL cell line SEM after 48 h incubation with DMSO (control), CX-4945 (Silmitasertib), Decitabine (DEC) or combined CX-4945 + DEC treatment. The Infinium MethylationEPIC BeadChip was used to obtain DNA methylation profiles across approximately 866,895 CpG islands.
2018-02-12 | GSE110454 | GEO
Project description:Wujiang water, sediment, and soil