follistatin CRISPR Activation Plasmid (h): sc-401687-ACT

Human FST encodes follistatin, a secreted glycoprotein that binds and neutralizes TGF-β superfamily ligands, particularly activins and several BMPs, thereby tuning SMAD2/3- and SMAD1/5/8-dependent transcriptional programs. By modulating ligand availability, follistatin influences cell growth, differentiation, tissue remodeling, and inflammatory crosstalk in diverse contexts including skeletal muscle, reproductive tissues, and the tumor microenvironment. Dysregulated FST expression has been associated with altered myogenesis and fibrosis-related signaling, reproductive axis perturbations, and cancer-relevant phenotypes linked to activin/BMP pathway imbalance. As a pathway gatekeeper, follistatin is frequently leveraged to interrogate TGF-β network dynamics and paracrine signaling effects in engineered cell models.

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

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

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