Sec61β CRISPR Activation Plasmid (h): sc-402791-ACT

SEC61B encodes Sec61β, a small subunit of the Sec61 heterotrimeric translocon embedded in the endoplasmic reticulum (ER) membrane that supports co-translational protein import and membrane protein integration. By coupling ribosome docking to the ER and coordinating with the signal recognition particle (SRP) pathway, Sec61β contributes to secretory proteostasis and ER quality control processes linked to the unfolded protein response and ER-associated degradation. Perturbations in translocon-dependent trafficking can influence the maturation of receptors, channels, and secreted factors, making SEC61B relevant to studies of ER stress, proteome imbalance, and broader mechanisms that shape cellular homeostasis. Because the Sec61 complex also impacts antigen presentation and the biogenesis of immune and metabolic regulators, SEC61B is frequently examined in functional genomics screens probing stress adaptation and protein handling phenotypes.

Sec61β CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous SEC61B expression without altering the underlying DNA sequence.

Sec61β CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the SEC61B 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 SEC61B transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous Sec61β expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native SEC61B locus and enabling the study of Sec61β-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of Sec61β pathway restoration in tumor cells with silenced or reduced SEC61B expression.

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