C3 CRISPR Activation Plasmid (m2): sc-419391-ACT-2

Mouse complement component 3 (C3) encodes the central effector protein of the complement system, whose proteolytic activation into C3a and C3b drives opsonization, immune complex clearance, chemotaxis, and amplification of innate immune responses through the classical, lectin, and alternative pathways. C3b deposition supports C5 convertase formation and interfaces with complement receptors to shape phagocytosis and antigen handling, linking complement activity to inflammatory signaling and crosstalk with coagulation and tissue injury programs. Dysregulated C3 activation is implicated in models of infection susceptibility, autoimmune and immune complex–mediated pathology, neuroinflammation, and metabolic inflammation, reflecting its broad influence on host defense and immunopathology. Gene editing of murine C3 enables mechanistic studies of complement-dependent effector functions, pathway-specific activation, and cell type–resolved contributions to inflammation and disease-relevant phenotypes in vivo and in primary immune cell systems.

C3 CRISPR Activation Plasmid (m2) provides a targeted, non-destructive approach to upregulating endogenous C3 expression without altering the underlying DNA sequence.

C3 CRISPR Activation Plasmid (m2) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the C3 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 C3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous C3 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native C3 locus and enabling the study of C3-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of C3 pathway restoration in tumor cells with silenced or reduced C3 expression.

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