KV1.4 CRISPR Activation Plasmid (h): sc-405990-ACT

KCNA4 encodes the human voltage-gated potassium channel KV1.4, a Shaker-related α-subunit that assembles into tetrameric channels to mediate fast-inactivating A-type K⁺ currents. By shaping action potential repolarization, interspike intervals, and synaptic excitability, KV1.4 contributes to activity-dependent control of membrane potential in excitable tissues. Channel availability and gating are regulated by phosphorylation and protein–protein interactions that influence trafficking and surface stability, linking KCNA4 to broader signaling processes that tune neuronal and cardiac excitability. Altered KV1-family current balance has been associated with dysregulated electrical signaling phenotypes relevant to studies of arrhythmogenic mechanisms, seizure susceptibility, and excitability disorders in model systems.

KV1.4 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous KCNA4 expression without altering the underlying DNA sequence.

KV1.4 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the KCNA4 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 KCNA4 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous KV1.4 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native KCNA4 locus and enabling the study of KV1.4-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of KV1.4 pathway restoration in tumor cells with silenced or reduced KCNA4 expression.

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