PSPH CRISPR Activation Plasmid (h): sc-403897-ACT

Phosphoserine phosphatase (PSPH) is a cytosolic enzyme that catalyzes the terminal step of the phosphorylated serine biosynthesis pathway, converting L-phosphoserine to L-serine. By controlling de novo serine availability, PSPH influences one-carbon metabolism, nucleotide synthesis, redox homeostasis, and downstream lipid and amino acid metabolism that support proliferative and stress-adaptive cellular programs. PSPH activity interfaces with metabolic rewiring commonly studied in rapidly dividing cells and nutrient-limited microenvironments, where serine flux can shape epigenetic regulation and oxidative stress responses. Dysregulated PSPH expression has been investigated in contexts of altered metabolism and growth control, making it relevant for mechanistic studies of metabolic pathway dependence.

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

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

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