HP1γ CRISPR Activation Plasmid (h): sc-417205-ACT

CBX3 encodes heterochromatin protein 1 gamma (HP1γ), a chromatin-associated factor that binds histone H3 lysine 9 methylation and helps organize higher-order chromatin structure. HP1γ participates in heterochromatin formation, transcriptional regulation, DNA replication, and DNA damage response through interactions with epigenetic writers/readers and RNA processing machinery. By shaping chromatin accessibility and genome stability, CBX3 influences cell-cycle progression, differentiation programs, and stress-responsive gene expression networks. Dysregulated HP1γ activity and altered CBX3 expression patterns have been linked to aberrant epigenetic states observed across multiple cancer and neurodevelopmental disease contexts, supporting its use as a mechanistic node in chromatin and genome maintenance studies.

HP1γ CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous CBX3 expression without altering the underlying DNA sequence.

HP1γ CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the CBX3 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 CBX3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous HP1γ expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native CBX3 locus and enabling the study of HP1γ-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of HP1γ pathway restoration in tumor cells with silenced or reduced CBX3 expression.

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