rapsyn CRISPR Activation Plasmid (h): sc-403991-ACT

Human RAPSN encodes rapsyn, a postsynaptic scaffolding protein essential for clustering and stabilizing nicotinic acetylcholine receptors (AChRs) at the neuromuscular junction. Rapsyn coordinates protein–protein interactions that organize the postsynaptic membrane and supports synapse maturation through receptor anchoring and cytoskeletal linkage. RAPSN function intersects with agrin–LRP4–MuSK signaling and downstream assembly processes that maintain efficient neuromuscular transmission. Disrupted RAPSN activity or expression is associated with congenital myasthenic syndromes and related neuromuscular junction disorders, making it a useful target for mechanistic studies of synaptic organization.

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

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

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