Fra1 CRISPR Activation Plasmid (h): sc-400527-ACT

FOSL1 encodes the AP-1 transcription factor subunit Fra1, a leucine-zipper protein that heterodimerizes with JUN family members to regulate stimulus-responsive gene expression. Fra1 activity is downstream of MAPK/ERK signaling and integrates cues from growth factor, cytokine, and stress pathways to control programs linked to proliferation, differentiation, extracellular matrix remodeling, and epithelial–mesenchymal transition. Dysregulated FOSL1 expression has been reported across multiple tumor contexts and inflammatory states, where it can reshape transcriptional networks governing invasion, lineage plasticity, and microenvironmental interactions. As a nuclear regulator, Fra1 serves as a useful node for dissecting AP-1–dependent enhancer usage and context-specific transcriptional circuitry in human cells.

Fra1 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous FOSL1 expression without altering the underlying DNA sequence.

Fra1 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the FOSL1 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 FOSL1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous Fra1 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native FOSL1 locus and enabling the study of Fra1-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of Fra1 pathway restoration in tumor cells with silenced or reduced FOSL1 expression.

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