STAM CRISPR Activation Plasmid (h): sc-402697-ACT

Human STAM (signal transducing adaptor molecule) is an endosomal adaptor that functions within the ESCRT-0 complex, partnering with HGS/Hrs to recognize ubiquitinated cargo and coordinate receptor sorting toward lysosomal degradation. Through its VHS and SH3 domains, STAM integrates ubiquitin-dependent trafficking with downstream modulation of growth factor and cytokine receptor signaling, influencing MAPK and JAK/STAT pathway amplitude and duration. This regulation is central to endocytosis, endosome maturation, and proteostasis, processes frequently altered in cancer biology and immune signaling. Dysregulated STAM-dependent receptor turnover has been linked to aberrant signal persistence and altered cellular responsiveness, making STAM a useful node for dissecting trafficking–signaling crosstalk.

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

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

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