HLF CRISPR Activation Plasmid (h): sc-404752-ACT

Human HLF (hepatic leukemia factor) encodes a PAR bZIP transcription factor that binds DNA regulatory elements to control gene programs involved in cellular differentiation, circadian-associated transcription, and stress-responsive gene expression. HLF participates in transcriptional networks that shape hematopoietic lineage identity and developmental timing, with downstream effects on cell-cycle control and survival pathways. Dysregulated HLF expression has been associated with altered hematopoietic states and oncogenic transcriptional reprogramming in leukemia-relevant contexts, making it a useful node for studying transcription factor–driven phenotypes. As a nuclear regulator, HLF is commonly investigated for its impact on promoter/enhancer activity, gene regulatory circuits, and lineage-specific transcriptional plasticity.

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

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

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