Chk1 Lentiviral Activation Particles (h): sc-400223-LAC

Human CHEK1 encodes checkpoint kinase 1 (Chk1), a serine/threonine kinase that coordinates the ATR-dependent DNA damage response to replication stress. Chk1 regulates S-phase progression and the G2/M checkpoint by phosphorylating effectors that restrain CDK activity, stabilize stalled replication forks, and promote homologous recombination-associated repair and cell-cycle arrest. This signaling axis interfaces with pathways governing genome integrity, including replication fork protection, origin firing control, and mitotic entry, making CHEK1 activity highly relevant to mechanisms of chromosomal instability. Dysregulation of CHEK1 pathway output is frequently studied in the context of tumor biology, genotoxic stress responses, and determinants of sensitivity to DNA-damaging perturbations in model systems.

Chk1 Lentiviral Activation Particles (h) address this need by packaging the complete synergistic activation mediator (SAM) transcriptional activation system into transduction-ready, high-titer lentiviral particles, enabling efficient CHEK1 upregulation across a broader range of human cell types.

Chk1 Lentiviral Activation Particles (h) deliver all functional components of the synergistic activation mediator (SAM) system via lentiviral transduction. The system comprises three particle preparations co-transduced into target cells: one encoding catalytically inactive dCas9 (D10A and N863A mutations) fused to the VP64 transactivation domain with a blasticidin resistance gene; one encoding the MS2-p65-HSF1 fusion protein with a hygromycin resistance gene; and one encoding a target-specific 20 nt sgRNA fused to two MS2 RNA aptamers with a puromycin resistance gene. Following lentiviral transduction and genomic integration of the expression cassettes, the SAM components are stably expressed and assemble at the target locus within the proximal promoter region upstream of the CHEK1 transcriptional start site, where VP64, p65, and HSF1 act cooperatively to recruit endogenous transcriptional machinery and drive sustained upregulation of endogenous Chk1 expression. The use of nuclease-inactive dCas9 avoids the introduction of double-strand DNA breaks and preserves the native CHEK1 genomic locus and regulatory architecture.

The lentiviral format offers several practical advantages: stable genomic integration supports heritable activation across cell divisions; high-titer particle preparations eliminate the need for in-house viral production; and compatibility with primary, non-dividing, and transfection-resistant cell types expands experimental accessibility. Successful transduction can be confirmed and enriched through triple antibiotic selection using puromycin, hygromycin, and blasticidin.

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