eIF4B CRISPR Activation Plasmid (h): sc-402494-ACT

Human EIF4B encodes eIF4B, a translation initiation factor that enhances RNA helicase activity of eIF4A and promotes 43S preinitiation complex recruitment to structured mRNAs, thereby increasing cap-dependent translation efficiency. eIF4B is regulated by growth factor and nutrient signaling, including PI3K–AKT–mTOR and MAPK pathways, through phosphorylation events that tune ribosome loading and protein synthesis rates. By influencing translation of transcripts involved in proliferation, stress responses, and survival, EIF4B contributes to cellular programs such as cell-cycle progression and adaptive translational control. Dysregulated eIF4B activity and phosphorylation have been associated with altered translational output in cancer biology and other diseases where protein synthesis control is perturbed.

eIF4B CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous EIF4B expression without altering the underlying DNA sequence.

eIF4B CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the EIF4B 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 EIF4B transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous eIF4B expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native EIF4B locus and enabling the study of eIF4B-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of eIF4B pathway restoration in tumor cells with silenced or reduced EIF4B expression.

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