TMEM55B CRISPR Activation Plasmid (h): sc-410227-ACT

TMEM55B encodes a transmembrane phosphoinositide phosphatase implicated in regulating phosphatidylinositol signaling by catalyzing dephosphorylation of phosphoinositide substrates, thereby influencing membrane identity and trafficking. Through modulation of endosomal and lysosomal membrane lipid composition, TMEM55B is linked to vesicular transport, receptor turnover, and broader control of intracellular signaling dynamics. Altered phosphoinositide homeostasis is associated with dysregulated cell growth and stress responses, making TMEM55B relevant to studies of pathway crosstalk that can impact proliferation and survival phenotypes. In human cell systems, TMEM55B expression and activity provide a useful entry point for interrogating lipid-driven regulation of organelle function and signaling networks in disease-relevant contexts.

TMEM55B CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous TMEM55B expression without altering the underlying DNA sequence.

TMEM55B CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the TMEM55B 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 TMEM55B transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous TMEM55B expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native TMEM55B locus and enabling the study of TMEM55B-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of TMEM55B pathway restoration in tumor cells with silenced or reduced TMEM55B expression.

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