FBXW5 CRISPR Activation Plasmid (h): sc-404410-ACT

FBXW5 encodes an F-box and WD-repeat–containing substrate receptor within SCF (SKP1–CUL1–F-box) E3 ubiquitin ligase complexes that confer target specificity for ubiquitin-mediated proteasomal degradation. Through regulated turnover of signaling and cell-cycle-associated proteins, FBXW5 contributes to proteostasis control, checkpoint coordination, and modulation of pathways linked to growth and stress responses. Altered ubiquitin–proteasome system activity involving F-box proteins is frequently connected to dysregulated proliferation and genomic stability, making FBXW5 a relevant node for mechanistic studies in cancer biology and related cellular phenotypes. As a human gene, FBXW5 is commonly investigated for how substrate recognition and degradation kinetics reshape pathway output in specific cellular contexts.

FBXW5 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous FBXW5 expression without altering the underlying DNA sequence.

FBXW5 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the FBXW5 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 FBXW5 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous FBXW5 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native FBXW5 locus and enabling the study of FBXW5-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of FBXW5 pathway restoration in tumor cells with silenced or reduced FBXW5 expression.

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