C1q-A CRISPR Activation Plasmid (h): sc-402156-ACT

C1QA encodes the A chain of complement component C1q, a recognition molecule that initiates the classical complement pathway by binding immune complexes and altered self surfaces. C1q participates in opsonization, clearance of apoptotic cells, and modulation of innate immune signaling, and is prominently expressed by macrophages and microglia where it shapes inflammatory programs. Through complement cascade activation and crosstalk with phagocytic and cytokine pathways, C1q influences synaptic pruning, tissue remodeling, and immune homeostasis. Dysregulated C1QA/C1q activity has been associated with autoimmune phenotypes, neuroinflammation, and complement-driven pathology, making it a useful target for mechanistic studies in immunology and neuroscience.

C1q-A CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous C1QA expression without altering the underlying DNA sequence.

C1q-A CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the C1QA 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 C1QA transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous C1q-A expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native C1QA locus and enabling the study of C1q-A-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of C1q-A pathway restoration in tumor cells with silenced or reduced C1QA expression.

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