XRN1 CRISPR Activation Plasmid (h): sc-401910-ACT

Human XRN1 encodes a highly conserved 5′–3′ exoribonuclease that drives cytoplasmic mRNA decay by degrading decapped transcripts and clearing RNA fragments generated during RNA turnover. XRN1 coordinates with decapping factors and processing bodies to shape transcriptome homeostasis, influencing pathways such as nonsense-mediated decay, microRNA-mediated silencing, and innate immune sensing of aberrant RNA. By regulating the stability of mRNAs involved in cell cycle control, differentiation, and stress responses, XRN1 helps maintain proteostasis and signaling fidelity. Dysregulated RNA decay and altered XRN1 activity have been linked to aberrant gene expression programs observed in cancer biology, neurodevelopmental phenotypes, and virus–host interactions, making it a useful node for mechanistic studies of post-transcriptional regulation.

XRN1 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous XRN1 expression without altering the underlying DNA sequence.

XRN1 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the XRN1 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 XRN1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous XRN1 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native XRN1 locus and enabling the study of XRN1-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of XRN1 pathway restoration in tumor cells with silenced or reduced XRN1 expression.

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