AP-4 CRISPR Activation Plasmid (h): sc-404336-ACT

TFAP4 encodes activating enhancer-binding protein 4 (AP-4), a basic helix–loop–helix leucine zipper transcription factor that binds E-box motifs and regulates programs controlling proliferation, differentiation, and cell-cycle progression. AP-4 integrates signals from oncogenic and developmental pathways, including MYC-driven transcriptional networks, and influences epithelial–mesenchymal transition, migration, and metabolic adaptation through downstream target genes. Dysregulated TFAP4 expression has been associated with altered growth control and invasive phenotypes across multiple cancer-relevant contexts, making it useful for studying transcriptional rewiring and context-dependent gene regulation. As a nuclear DNA-binding regulator, AP-4 provides a tractable node for dissecting promoter/enhancer activity and chromatin-dependent control of gene expression.

AP-4 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous TFAP4 expression without altering the underlying DNA sequence.

AP-4 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the TFAP4 locus in human cell lines. The system is built around a catalytically inactive Cas9 (dCas9) carrying two inactivating mutations (D10A and N863A) that eliminate nuclease activity while preserving DNA binding. This dCas9 is fused to VP64, a potent transcriptional activator, and is co-expressed with a blasticidin resistance gene for selection. The second plasmid encodes the MS2-p65-HSF1 fusion protein, a secondary activator complex that works in concert with dCas9-VP64, alongside a hygromycin resistance gene. The third plasmid encodes a target-specific 20 nt sgRNA fused to two MS2 RNA aptamers that recruit the MS2-p65-HSF1 complex to the activation site, accompanied by a puromycin resistance gene. The three plasmids are delivered at a 1:1:1 mass ratio for balanced expression of all system components.

Once assembled at the target locus, the SAM complex binds within approximately 200 bp upstream of the TFAP4 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous AP-4 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native TFAP4 locus and enabling the study of AP-4-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of AP-4 pathway restoration in tumor cells with silenced or reduced TFAP4 expression.

For Research Use Only. Not Intended for Diagnostic or Therapeutic Use.