The KRT5 Knockout 143B Polyclonal Cells are a CRISPR/Cas9-edited pooled population with targeted disruption of the KRT5 gene, encoding keratin 5. This loss-of-function model enables investigation of keratin intermediate filaments in malignant bone tumor biology without clonal selection biases. The polyclonal format reflects heterogeneous knockout effects, suitable for comparative studies with wild-type 143B in cytoskeletal architecture, cell adhesion, and signaling assays.
The 143B cell line is a highly metastatic derivative of HOS human osteosarcoma, extensively used to model bone cancer metastasis and invasion. Exhibiting rapid proliferation, anchorage-independent growth, and robust pulmonary metastasis in xenografts, 143B provides a mesenchymal background to study the ectopic expression of epithelial-specific keratin KRT5 in sarcoma.
Keratin 5 forms intermediate filaments with keratin 14, providing mechanical integrity and participating in signal transduction. KRT5 is transcriptionally regulated by p63 and AP-1 downstream of EGF and TGF-??, and integrates with Wnt/??-catenin. Its filament network interacts with desmoplakin, plakoglobin, periplakin, and plakophilin at desmosomes. KRT5 disruption modulates Akt and ERK phosphorylation and 14-3-3 protein function, affecting cell adhesion and MAPK signaling.
In 143B osteosarcoma cells, ablation of KRT5 is anticipated to destabilize residual keratin intermediate filament networks, potentially diminishing epithelial-like characteristics. Loss of KRT5 compromises the scaffolding linking actin and microtubules to desmosomal cell-cell contacts, thus altering adhesion and collective migration. Consequently, the knockout cells are expected to exhibit attenuated Akt and MAPK pathway activities, which may reduce invasive capacity and modulate metastatic potential.
Applications include Boyden chamber invasion/migration assays, immunofluorescence microscopy for keratin network visualization, and Western blotting for phosphorylated Akt and ERK. Apoptosis and cell adhesion assays further characterize phenotypes. The cells serve as controls in drug screening targeting keratin-dependent signaling or cytoskeletal integrity, and RNA-seq enables transcriptomic profiling downstream of KRT5 disruption. For technical support, contact Ascent Research.
