Mucin 5B/MUC5B CRISPR Activation Plasmid (h): sc-401077-ACT

MUC5B encodes mucin 5B, a high–molecular weight gel-forming mucin that is heavily O-glycosylated and secreted to form the viscoelastic mucus barrier on airway and other mucosal epithelia. MUC5B contributes to mucociliary clearance by regulating mucus hydration, polymer crosslinking, and pathogen entrapment, integrating with epithelial differentiation programs and inflammatory signaling that reshape the extracellular surface environment. Its expression is influenced by cytokine-driven pathways and ER/Golgi secretory processing that coordinate mucin biosynthesis and export. Dysregulated MUC5B levels and altered mucus rheology are widely studied in chronic airway inflammation and fibrotic lung biology, making it a common target for mechanistic modeling of epithelial homeostasis.

Mucin 5B/MUC5B CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous MUC5B expression without altering the underlying DNA sequence.

Mucin 5B/MUC5B CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the MUC5B 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 MUC5B transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous Mucin 5B/MUC5B expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native MUC5B locus and enabling the study of Mucin 5B/MUC5B-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of Mucin 5B/MUC5B pathway restoration in tumor cells with silenced or reduced MUC5B expression.

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