St3Gal-III CRISPR Activation Plasmid (h): sc-406298-ACT

ST3GAL3 encodes the human sialyltransferase St3Gal-III, a Golgi-resident enzyme that catalyzes the transfer of sialic acid in an α2,3 linkage onto galactose-containing glycoconjugates. By shaping terminal sialylation patterns on N- and O-linked glycans and glycolipids, St3Gal-III influences glycoprotein trafficking, cell–cell recognition, receptor signaling dynamics, and immune-modulatory carbohydrate epitopes. This activity connects ST3GAL3 to broader glycosylation and secretory pathway processes that regulate adhesion and migration through remodeling of the cell-surface glycome. Genetic or regulatory perturbation of ST3GAL3 has been associated with neurodevelopmental phenotypes and altered glycan signatures relevant to disease biology, making it a useful target for mechanistic studies of sialylation-dependent pathways.

St3Gal-III CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous ST3GAL3 expression without altering the underlying DNA sequence.

St3Gal-III CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the ST3GAL3 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 ST3GAL3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous St3Gal-III expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native ST3GAL3 locus and enabling the study of St3Gal-III-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of St3Gal-III pathway restoration in tumor cells with silenced or reduced ST3GAL3 expression.

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