CAV3 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the near-haploid human HAP1 cell line, designed for loss-of-function studies of the CAV3 gene. This heterogeneous pool of cells carries targeted disruptions in CAV3, resulting in the absence of functional caveolin-3 protein, the muscle-specific caveolin essential for sarcolemmal caveolae formation and signal transduction scaffolding.
HAP1 is a near-haploid cell line originally derived from the chronic myeloid leukemia cell line KBM-7. Its haploid karyotype simplifies genetic manipulation and ensures unambiguous genotype-phenotype correlations, eliminating diploid gene redundancy. Although not of muscle origin, HAP1 cells provide a reductionist system to study CAV3-dependent processes, as they express relevant signaling components and caveolar machinery, and the haploid background enhances loss-of-function phenotype penetrance.
CAV3 encodes caveolin-3, a muscle-specific integral membrane protein that oligomerizes to form the structural coat of caveolae. Caveolin-3 scaffolds signaling molecules such as eNOS, the insulin receptor, Src family kinases, and integrins, interacting with dystrophin, dysferlin, and myoferlin to maintain sarcolemmal integrity and mechanotransduction. Its transcription is regulated by MEF2, MyoD, SRF, mechanical stretch, and insulin. Disruption of CAV3 abrogates caveolae formation, dysregulating downstream effectors like PI3K, AKT, and heterotrimeric G proteins, and impairing TGF-beta, insulin, and integrin signaling pathways. This dysfunction is linked to limb-girdle muscular dystrophy 1C, rippling muscle disease, and familial hypertrophic cardiomyopathy.
In HAP1 cells, CAV3 knockout provides a clean loss-of-function model free from muscle-specific confounders, allowing dissection of caveolin-3??s scaffolding functions and protein interactions. The haploid background eliminates residual caveolin-3 activity, making it ideal for ectopic expression and rescue experiments to map functional domains. Key caveolinopathy features, like altered eNOS activity and defective membrane repair, can be recapitulated, offering a tractable platform for mechanistic studies.
This polyclonal knockout model supports co-immunoprecipitation for interactome mapping, western blotting for signaling readouts (e.g., phospho-AKT, Src), and immunofluorescence to visualize caveolae upon CAV3 re-expression. It is suitable for flow cytometry assays and high-throughput screens targeting caveolar pathways, facilitating drug target validation for muscular dystrophies and investigations into membrane trafficking and mechanotransduction. For further details, contact Ascent Research.
