DNA Ligase I Lentiviral Activation Particles (h): sc-402830-LAC

Human LIG1 encodes DNA Ligase I, an ATP-dependent ligase that seals DNA nicks by catalyzing phosphodiester bond formation during lagging-strand DNA replication, processing of Okazaki fragments, and long-patch base excision repair. DNA Ligase I functions at the replication fork and within DNA damage response networks coordinated with PCNA, RFC, FEN1, and polymerases, supporting genome stability and faithful cell-cycle progression. Perturbation of LIG1 activity or expression is associated with elevated replication stress, accumulation of strand breaks, and mutational burden that can impact oncogenesis and other genome instability phenotypes. As a core factor in replication-coupled repair, LIG1 is commonly studied in pathways governing S-phase checkpoints, chromatin maintenance, and responses to oxidative or alkylation damage.

DNA Ligase I 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 LIG1 upregulation across a broader range of human cell types.

DNA Ligase I 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 LIG1 transcriptional start site, where VP64, p65, and HSF1 act cooperatively to recruit endogenous transcriptional machinery and drive sustained upregulation of endogenous DNA Ligase I expression. The use of nuclease-inactive dCas9 avoids the introduction of double-strand DNA breaks and preserves the native LIG1 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.