FXR/NR1H4 CRISPR Activation Plasmid (h): sc-417410-ACT

NR1H4 encodes farnesoid X receptor (FXR), a ligand-activated nuclear receptor that functions as a transcriptional sensor for bile acids and coordinates metabolic gene programs. In hepatocytes and enterocytes, FXR regulates bile acid synthesis and transport (including feedback control of CYP7A1), lipid and glucose homeostasis, and inflammatory signaling through crosstalk with pathways such as SHP, FGF19/FGF15, and NF-κB. FXR activity shapes enterohepatic circulation and influences intestinal barrier function and gut–liver axis communication. Dysregulated NR1H4/FXR signaling has been implicated in cholestatic liver injury, nonalcoholic fatty liver disease, and hepatobiliary carcinogenesis, making it a key node for mechanistic studies of metabolic and inflammatory liver biology.

FXR/NR1H4 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous NR1H4 expression without altering the underlying DNA sequence.

FXR/NR1H4 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the NR1H4 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 NR1H4 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous FXR/NR1H4 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native NR1H4 locus and enabling the study of FXR/NR1H4-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of FXR/NR1H4 pathway restoration in tumor cells with silenced or reduced NR1H4 expression.

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