CKR-4 CRISPR Activation Plasmid (h): sc-404778-ACT

Human CCR4 (CKR-4) is a chemokine receptor in the GPCR family that binds ligands such as CCL17 and CCL22 to direct chemotaxis, cell positioning, and activation programs in immune cells. CCR4 signaling engages heterotrimeric G proteins and downstream pathways including PI3K–AKT, MAPK, and calcium flux, shaping trafficking and cytokine responses in the tissue microenvironment. It is frequently studied in the context of T cell subset localization and tumor–immune interactions, where altered receptor expression can influence infiltration patterns and immune regulation. Dysregulated CCR4 expression has been associated with inflammatory states and malignancies, making it a useful node for mechanistic studies of immune cell migration and microenvironmental cues.

CKR-4 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous CCR4 expression without altering the underlying DNA sequence.

CKR-4 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the CCR4 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 CCR4 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous CKR-4 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native CCR4 locus and enabling the study of CKR-4-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of CKR-4 pathway restoration in tumor cells with silenced or reduced CCR4 expression.

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