Sigma Receptor CRISPR Activation Plasmid (m): sc-422068-ACT

Sigmar1 encodes the sigma-1 receptor, an endoplasmic reticulum (ER) membrane chaperone enriched at mitochondria-associated ER membranes where it modulates ER–mitochondrial Ca2+ exchange, proteostasis, and cellular stress responses. Sigma-1 receptor interacts with ion channels and signaling complexes to influence neurotransmission, lipid remodeling, and redox homeostasis, integrating pathways linked to unfolded protein response and mitochondrial bioenergetics. In mouse systems, Sigmar1 activity has been connected to neuronal maintenance, synaptic plasticity, and regulation of inflammatory signaling in glial and peripheral immune contexts. Dysregulation of sigma-1 receptor–dependent homeostasis is studied in models of neurodegeneration, neuropathic pain, and cardiometabolic stress, supporting its relevance for mechanistic pathway interrogation.

Sigma Receptor CRISPR Activation Plasmid (m) provides a targeted, non-destructive approach to upregulating endogenous Sigmar1 expression without altering the underlying DNA sequence.

Sigma Receptor CRISPR Activation Plasmid (m) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the Sigmar1 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 Sigmar1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous Sigma Receptor expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native Sigmar1 locus and enabling the study of Sigma Receptor-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of Sigma Receptor pathway restoration in tumor cells with silenced or reduced Sigmar1 expression.

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