MUS81 CRISPR Activation Plasmid (h): sc-402664-ACT

Human MUS81 encodes a structure-specific endonuclease that partners with EME1/EME2 to resolve stalled replication forks and recombination intermediates, including nicked Holliday junctions, D-loops, and 3′ flaps. MUS81 functions in DNA damage response networks and maintains genome stability through coordinated action with homologous recombination, Fanconi anemia-associated repair, and replication stress tolerance pathways. By controlling processing of aberrant DNA structures, MUS81 influences checkpoint signaling and chromosome segregation fidelity during S phase and mitosis. Dysregulation of MUS81 activity or pathway balance has been associated with altered replication stress handling and genomic instability phenotypes relevant to cancer biology and inherited DNA repair defects.

MUS81 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous MUS81 expression without altering the underlying DNA sequence.

MUS81 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the MUS81 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 MUS81 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous MUS81 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native MUS81 locus and enabling the study of MUS81-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of MUS81 pathway restoration in tumor cells with silenced or reduced MUS81 expression.

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