CT45-1 CRISPR Activation Plasmid (h): sc-416782-ACT

CT45A1 encodes CT45-1, a cancer/testis antigen with highly restricted expression in normal adult tissues and frequent re-expression in multiple tumor contexts, making it a useful marker for studying epigenetic dysregulation and lineage-inappropriate transcription. Although its precise molecular function remains incompletely defined, CT45-1 has been linked to transcriptional programs associated with cellular plasticity and stress-adaptive states, including processes that support proliferation and survival under oncogenic signaling. Aberrant CT45A1 expression is commonly associated with tumor immunogenicity and heterogeneity, and is often studied alongside other germline-restricted antigens that reflect altered chromatin states. These features make CT45A1/CT45-1 relevant for investigating regulatory circuits that couple chromatin remodeling, transcriptional control, and tumor-associated antigen expression.

CT45-1 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous CT45A1 expression without altering the underlying DNA sequence.

CT45-1 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the CT45A1 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 CT45A1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous CT45-1 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native CT45A1 locus and enabling the study of CT45-1-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of CT45-1 pathway restoration in tumor cells with silenced or reduced CT45A1 expression.

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