Blk CRISPR Activation Plasmid (h): sc-402737-ACT

BLK encodes B lymphoid tyrosine kinase (Blk), a Src family non-receptor kinase predominantly expressed in B cells where it couples the B-cell receptor to downstream signaling networks. Blk participates in phosphorylation cascades that modulate PI3K–AKT, MAPK/ERK, and NF-κB pathway activity, influencing antigen-dependent activation thresholds, proliferation, and differentiation. Altered BLK expression or regulatory variation has been associated with immune dysregulation and susceptibility to autoimmune phenotypes, making it a useful node for dissecting B-cell signaling circuitry. Human BLK is also studied in the context of hematopoietic lineage biology and transcriptional programs that govern B-cell development.

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

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

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