MMS22L CRISPR Activation Plasmid (h): sc-408097-ACT

MMS22L encodes a nuclear protein that forms a functional complex with TONSL to support homologous recombination–mediated DNA repair during S phase, particularly at stalled or collapsed replication forks. By promoting replication-coupled repair and chromatin-associated recruitment of repair factors, MMS22L contributes to genome stability and proper recovery from replication stress. Disruption of MMS22L-dependent pathways is linked to elevated DNA damage signaling, aberrant fork processing, and chromosomal instability, processes that are frequently leveraged in studies of cancer biology and genome maintenance. As a replication stress response factor, MMS22L is commonly investigated in the context of DNA damage response networks, cell-cycle control, and sensitivity to genotoxic perturbations.

MMS22L CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous MMS22L expression without altering the underlying DNA sequence.

MMS22L CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the MMS22L 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 MMS22L transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous MMS22L expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native MMS22L locus and enabling the study of MMS22L-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of MMS22L pathway restoration in tumor cells with silenced or reduced MMS22L expression.

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