CRALBP CRISPR Activation Plasmid (h): sc-402092-ACT

RLBP1 encodes cellular retinaldehyde-binding protein (CRALBP), a soluble retinoid chaperone enriched in retinal pigment epithelium and Müller glia that binds 11-cis-retinal and 11-cis-retinol. By stabilizing and trafficking cis-retinoid intermediates, CRALBP supports retinoid isomerization and recycling steps that maintain photoreceptor chromophore availability in the visual cycle. This activity links RLBP1 to retinoid metabolism, subcellular retinoid transport, and light-dependent recovery of phototransduction competence. Altered RLBP1 expression or function is associated with inherited retinal dystrophies characterized by impaired dark adaptation and progressive retinal degeneration, making it a useful node for studying retinal homeostasis and stress responses.

CRALBP CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous RLBP1 expression without altering the underlying DNA sequence.

CRALBP CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the RLBP1 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 RLBP1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous CRALBP expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native RLBP1 locus and enabling the study of CRALBP-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of CRALBP pathway restoration in tumor cells with silenced or reduced RLBP1 expression.

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