Search PubMedSearch

SEARCH · Search PubMed

Results for “Octamer Transcription Factor-3”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

5 recordsLinked to original sources

The cGAS-STING pathway is a master regulator of OCT4 expression in persistent sarcoma cells and enhances cellular immunotherapy with NK and CIK lymphocytes.

Advanced sarcomas have a poor prognosis and limited therapeutic options. Disease recurrence is caused by persistent cells that survive drug treatments. The alkylating agent trabectedin, when combined with the poly (ADP-ribose) polymerase 1 (PARP1) inhibitor olaparib, exhibits variable antitumor effects in advanced sarcomas. In this study, we demonstrate that the expression of the transcription factor OCT4 is upregulated in persistent cells that survive treatment with trabectedin and olaparib, through the cGAS-STING-IRF3-IFNβ pathway. This route also leads to the upregulation of natural killer (NK) and cytokine-induced killer (CIK) lymphocyte activating ligands. These molecular events enhance the antitumor efficacy of immunotherapy with NK and CIK cells, targeting both the bulk population and residual drug-tolerant cells. In conclusion, the activation of the cGAS-STING pathway has a double-edged effect, enriching the OCT4+ persistent cell population while increasing the expression of NK/CIK ligands. The addition of olaparib to trabectedin potentiates the cGAS-STING pathway activation and the upregulation of NKG2DLs, while simultaneously counteracting the OCT4 overexpression. Therefore, sequential treatment with trabectedin and olaparib followed by NK/CIK immunotherapy represents a promising strategy against advanced sarcomas and warrants further investigation.

Humans

In vivo differentiation of embryonic cells devoid of key reprogramming factors.

Embryonic cell differentiation depends on reprogramming of the oocyte and sperm nucleus into a transient totipotent state. In zebrafish, this coincides with genome activation, which is regulated by the pioneer factors Nanog, Pou5f3, and Sox19b (NPS). Here, we investigate the role of NPS in developmental reprogramming and differentiation by analyzing the fate of NPS mutant cells in a wild-type embryo using single-cell RNA-seq. We find that many cells fail to activate transcription or undergo cell death, while others acquire gene expression profiles that resemble germ cells, neural progenitors, and motoneuron states. These cells achieve intermediate transcriptional states, revealing the essential role of NPS in coordinating nuclear and cytoplasmic reprogramming and preventing the premature activation of lineage-specific differentiation programs. These results demonstrate that most developmental programs require developmental reprogramming by NPS, yet some cells can bypass transient totipotency to achieve intermediate developmental states resembling wild-type states in vivo.

Animals

A chemical epigenetic tool to probe site-specific DNA-binding protein complexes.

Site-specific DNA binding by proteins is critical for regulating transcriptional activity and cell fate decision. However, identifying proteins bound to specific genomic regions (e.g., promoter or enhancer regions) remains challenging. To address this, we developed a chemical epigenetic tool, named Site-specific noncanonical amino acid-mediated capture of protein (SCOPE), incorporating a photo-crosslinking amino acid into a nuclease-deficient dCas9 mutant. Human pluripotent stem cells (hPSCs) carrying SCOPE enable the capture of proteins bound to, in theory, any genomic location, facilitating the study of the cell context-dependent DNA-protein interactions. Using SCOPE, we identified the OCT4/SOX2/CARHSP1 complex binding to the NANOG promoter to maintain pluripotency in hPSCs. During ectoderm differentiation, ZIC2 acts as a competitive inhibitor, binding the same promoter region to downregulate NANOG expression and promote differentiation. Additionally, SCOPE identified that ZNF8 binds to the distal regulatory region of OCT4 to maintain naïve pluripotency. In summary, SCOPE provides a robust system for uncovering cell context-dependent, site-specific genome regulators, offering valuable insights into gene regulation networks driving cell fate transitions.

Humans

Profiling the long noncoding RNA interaction network in the regulatory elements of target genes by chromatin in situ reverse transcription sequencing.

Long noncoding RNAs (lncRNAs) can regulate the activity of target genes by participating in the organization of chromatin architecture. We have devised a "chromatin-RNA in situ reverse transcription sequencing" (CRIST-seq) approach to profile the lncRNA interaction network in gene regulatory elements by combining the simplicity of RNA biotin labeling with the specificity of the CRISPR/Cas9 system. Using gene-specific gRNAs, we describe a pluripotency-specific lncRNA interacting network in the promoters of Sox2 and Pou5f1, two critical stem cell factors that are required for the maintenance of pluripotency. The promoter-interacting lncRNAs were specifically activated during reprogramming into pluripotency. Knockdown of these lncRNAs caused the stem cells to exit from pluripotency. In contrast, overexpression of the pluripotency-associated lncRNA activated the promoters of core stem cell factor genes and enhanced fibroblast reprogramming into pluripotency. These CRIST-seq data suggest that the Sox2 and Pou5f1 promoters are organized within a unique lncRNA interaction network that determines the fate of pluripotency during reprogramming. This CRIST approach may be broadly used to map lncRNA interaction networks at target loci across the genome.

Animals

H3K4me2 distinguishes a distinct class of enhancers during the maternal-to-zygotic transition.

After egg fertilization, an initially silent embryonic genome is transcriptionally activated during the maternal-to-zygotic transition. In zebrafish, maternal vertebrate pluripotency factors Nanog, Pou5f3 (OCT4 homolog), and Sox19b (SOX2 homolog) (NPS) play essential roles in orchestrating embryonic genome activation, acting as "pioneers" that open condensed chromatin and mediate acquisition of activating histone modifications. However, some embryonic gene transcription still occurs in the absence of these factors, suggesting the existence of other mechanisms regulating genome activation. To identify chromatin signatures of these unknown pathways, we profiled the histone modification landscape of zebrafish embryos using CUT&RUN. Our regulatory map revealed two subclasses of enhancers distinguished by presence or absence of H3K4me2. Enhancers lacking H3K4me2 tend to require NPS factors for de novo activation, while enhancers bearing H3K4me2 are epigenetically bookmarked by DNA hypomethylation to recapitulate gamete activity in the embryo, independent of NPS pioneering. Thus, parallel enhancer activation pathways combine to induce transcriptional reprogramming to pluripotency in the early embryo.

Animals