CIS CRISPR Activation Plasmid (h): sc-402619-ACT

Human CISH encodes cytokine-inducible SH2-containing protein (CIS), a SOCS family adaptor that attenuates cytokine receptor signaling by binding phosphorylated targets and promoting ubiquitin-mediated turnover. CIS acts as a negative feedback regulator of JAK/STAT pathways downstream of receptors for IL-2 family cytokines and related immunomodulatory cues, shaping lymphocyte activation, proliferation, and differentiation. Through its SH2 domain and SOCS box, CIS influences signaling amplitude and duration that intersect with broader inflammatory and growth-regulatory programs. Dysregulated CISH expression or CIS activity has been linked to altered immune responsiveness and inflammatory disease biology, making it a useful node for mechanistic studies of cytokine signaling networks.

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

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

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