HoxB4 CRISPR Activation Plasmid (h): sc-404013-ACT

HOXB4 encodes the homeobox transcription factor HoxB4, a DNA-binding regulator that controls anterior–posterior patterning programs during embryonic development and helps maintain lineage-specifying transcriptional networks in hematopoietic and other progenitor populations. As part of HOX gene regulatory circuitry, HoxB4 influences chromatin state and coordinated expression of differentiation and self-renewal genes, intersecting with pathways that govern stem cell fate decisions and developmental timing. Dysregulated HOXB4 expression and altered HOX cluster activity have been reported in multiple malignancies, including hematologic cancers, where aberrant developmental transcriptional programs can contribute to impaired differentiation and proliferative signaling. These properties make HOXB4 a useful node for dissecting developmental gene control, epigenetic regulation, and oncogenic transcriptional reprogramming in human cell models.

HoxB4 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous HOXB4 expression without altering the underlying DNA sequence.

HoxB4 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the HOXB4 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 HOXB4 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous HoxB4 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native HOXB4 locus and enabling the study of HoxB4-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of HoxB4 pathway restoration in tumor cells with silenced or reduced HOXB4 expression.

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