MYH3 CRISPR Activation Plasmid (h): sc-400555-ACT

MYH3 encodes the embryonic skeletal muscle myosin heavy chain, a core component of the thick filament motor that converts ATP hydrolysis into contractile force. It plays a central role in myofibrillogenesis and sarcomere organization during early myogenesis, coordinating actin–myosin interactions required for muscle fiber formation and maturation. MYH3 expression integrates with developmental transcriptional programs and cytoskeletal assembly pathways that shape muscle architecture and contractile properties. Genetic variation or dysregulated expression of MYH3 has been linked to congenital disorders of skeletal muscle development characterized by impaired contractility and abnormal musculoskeletal patterning, making it a relevant target for studying developmental myopathies.

MYH3 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous MYH3 expression without altering the underlying DNA sequence.

MYH3 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the MYH3 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 MYH3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous MYH3 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native MYH3 locus and enabling the study of MYH3-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of MYH3 pathway restoration in tumor cells with silenced or reduced MYH3 expression.

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