OAS3 CRISPR Activation Plasmid (h): sc-405992-ACT

Human OAS3 (2′-5′-oligoadenylate synthetase 3) is an interferon-stimulated enzyme that detects viral and cellular double-stranded RNA and catalyzes synthesis of 2′-5′-linked oligoadenylates. These second messengers activate RNase L, promoting targeted RNA degradation and shaping innate immune signaling programs that intersect with antiviral restriction, inflammatory transcription, and stress responses. OAS3 activity integrates into interferon/JAK–STAT-regulated pathways and contributes to cellular control of RNA homeostasis during infection. Dysregulated OAS3–RNase L signaling has been investigated in the context of susceptibility to viral infection, aberrant interferon signatures, and inflammatory disease states.

OAS3 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous OAS3 expression without altering the underlying DNA sequence.

OAS3 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the OAS3 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 OAS3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous OAS3 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native OAS3 locus and enabling the study of OAS3-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of OAS3 pathway restoration in tumor cells with silenced or reduced OAS3 expression.

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