HSF1 CRISPR Activation Plasmid (h): sc-400432-ACT

Heat shock factor 1 (HSF1) is a master transcriptional regulator of the cellular heat shock response that maintains proteostasis under stress by inducing heat shock proteins and co-chaperones, including HSP70 and HSP90 networks. In human cells, HSF1 integrates proteotoxic stress signals with transcriptional and translational control programs, shaping responses to oxidative stress, protein misfolding, and environmental challenges. HSF1 activity intersects with pathways governing protein quality control, autophagy, and cellular survival decisions, and altered regulation of HSF1-linked stress programs has been associated with cancer biology and neurodegenerative disease mechanisms. Modulating HSF1 expression is therefore useful for dissecting stress-adaptation circuitry and downstream transcriptome remodeling in diverse cell models.

HSF1 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous HSF1 expression without altering the underlying DNA sequence.

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

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