OPN1LW CRISPR Activation Plasmid (h): sc-417309-ACT

OPN1LW encodes the long-wavelength–sensitive opsin (L-cone opsin), a GPCR-like photopigment expressed in retinal cone photoreceptors that initiates phototransduction in response to red light. Upon photon absorption and 11-cis-retinal isomerization, OPN1LW activates the transducin–PDE6 cascade to reduce cGMP levels, close cyclic nucleotide–gated channels, and modulate membrane potential and synaptic signaling in the visual pathway. Its expression is tightly controlled by cone-specific transcriptional programs and chromatin context within the opsin gene cluster on Xq28, contributing to spectral tuning and cone subtype identity. Variants and dysregulated expression of OPN1LW are associated with inherited color vision deficiencies and cone photoreceptor dysfunction, providing a molecular entry point for studying genotype–phenotype relationships in human vision biology.

OPN1LW CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous OPN1LW expression without altering the underlying DNA sequence.

OPN1LW CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the OPN1LW 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 OPN1LW transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous OPN1LW expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native OPN1LW locus and enabling the study of OPN1LW-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of OPN1LW pathway restoration in tumor cells with silenced or reduced OPN1LW expression.

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