Csk CRISPR Activation Plasmid (h): sc-400992-ACT

Human CSK encodes Csk, a cytosolic non-receptor tyrosine kinase that negatively regulates Src family kinases by phosphorylating their C-terminal inhibitory tyrosine, thereby constraining signaling from immune receptors, integrins, and growth factor pathways. Through this gatekeeping role, Csk shapes downstream MAPK/ERK, PI3K–AKT, and cytoskeletal remodeling programs that influence adhesion, migration, and cell activation thresholds. Altered CSK activity or regulation has been linked to dysregulated immune signaling and inflammatory phenotypes, and it is frequently studied in contexts where Src-driven phosphorylation networks contribute to aberrant proliferation and invasion biology. As a central modulator of Src family kinase signaling, Csk is relevant to systems-level analyses of tyrosine phosphorylation circuits and their association with autoimmune and cancer-related signaling states.

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

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

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