C5 CRISPR Activation Plasmid (h): sc-401533-ACT

Human complement component 5 (C5) encodes a central effector of the complement cascade that is cleaved into C5a and C5b during classical, lectin, or alternative pathway activation. C5a functions as a potent anaphylatoxin that signals through C5a receptors to promote chemotaxis, cytokine release, and myeloid cell activation, while C5b initiates assembly of the terminal membrane attack complex (C5b–C9) to drive target cell lysis. Through these processes, C5 integrates innate immune recognition with inflammatory amplification and microbial defense. Dysregulated C5 activation is frequently studied in the context of complement-driven inflammation, vascular injury, and autoimmune-associated tissue damage, where altered C5a signaling and MAC formation can contribute to pathology.

C5 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous C5 expression without altering the underlying DNA sequence.

C5 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the C5 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 C5 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous C5 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native C5 locus and enabling the study of C5-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of C5 pathway restoration in tumor cells with silenced or reduced C5 expression.

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