52 kDa Ro/SSA CRISPR Activation Plasmid (h): sc-400885-ACT

TRIM21 encodes the 52 kDa Ro/SSA protein, an E3 ubiquitin ligase that functions as a cytosolic Fc receptor to couple antibody-bound targets to ubiquitin-dependent proteasomal degradation. It modulates innate immune signaling and inflammatory gene programs by regulating key intermediates in pathways such as type I interferon and NF-κB, thereby shaping antiviral and stress responses. TRIM21 also participates in protein quality control and turnover of signaling complexes, linking ubiquitination to transcriptional outputs. Dysregulation of Ro/SSA-associated immune recognition and TRIM21-controlled signaling has been implicated in autoantibody-associated autoimmune phenotypes, making it relevant for mechanistic studies of immune tolerance and inflammation.

52 kDa Ro/SSA CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous TRIM21 expression without altering the underlying DNA sequence.

52 kDa Ro/SSA CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the TRIM21 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 TRIM21 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous 52 kDa Ro/SSA expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native TRIM21 locus and enabling the study of 52 kDa Ro/SSA-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of 52 kDa Ro/SSA pathway restoration in tumor cells with silenced or reduced TRIM21 expression.

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