MTMR5 CRISPR Activation Plasmid (h): sc-410999-ACT

SBF1 encodes MTMR5, a catalytically inactive myotubularin-related pseudophosphatase that functions as a scaffold in phosphoinositide signaling and endosomal membrane trafficking. MTMR5 interacts with active myotubularins such as MTMR2 to regulate phosphatidylinositol 3-phosphate and phosphatidylinositol 3,5-bisphosphate homeostasis, influencing endosome–lysosome dynamics, receptor turnover, and cytoskeletal organization. Through these processes, SBF1 has been linked to pathways governing myelination, axonal maintenance, and cellular stress responses. Genetic variation and dysregulated expression in this axis are associated with inherited neuropathy phenotypes and broader neurodevelopmental and tumor-biology contexts where trafficking-dependent signaling is altered.

MTMR5 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous SBF1 expression without altering the underlying DNA sequence.

MTMR5 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the SBF1 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 SBF1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous MTMR5 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native SBF1 locus and enabling the study of MTMR5-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of MTMR5 pathway restoration in tumor cells with silenced or reduced SBF1 expression.

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