OSM CRISPR Activation Plasmid (h): sc-404957-ACT

Oncostatin M (OSM) is a pleiotropic cytokine of the IL-6 family that signals primarily through OSMR or LIFR in combination with gp130 to regulate inflammation, tissue remodeling, and hematopoietic and stromal cell crosstalk. OSM stimulation activates JAK/STAT (notably STAT3), MAPK/ERK, and PI3K/AKT pathways, reshaping transcriptional programs that influence cell proliferation, differentiation, extracellular matrix turnover, and barrier function. In human biology, dysregulated OSM activity has been linked to chronic inflammatory microenvironments and fibrotic remodeling, with additional relevance to tumor-associated stroma, angiogenic signaling, and immune cell recruitment. These features make OSM a useful node for studying cytokine-driven transcriptional networks, paracrine signaling, and pathway coupling across immune and non-immune compartments.

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

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

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