The EIF2AK2 Knockout 143B Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal knockout population generated from 143B human osteosarcoma cells, with targeted disruption of the EIF2AK2 (PKR) gene. This heterogeneous pool contains cells bearing varied edits, yielding a loss-of-function model without clonal selection, ideal for pooled screens and studies where population diversity minimizes clonal biases. This format avoids the artifacts of monoclonal expansion and provides a robust starting material for functional genomics and drug-resistance screens.
The 143B host line is a human osteosarcoma cell line derived as a TK-negative derivative of HOS, offering a well-characterized bone cancer model. Its tumorigenic phenotype, stable karyotype, and adherent growth properties render it suitable for a wide range of oncology experiments, including proliferation, migration, and drug-response assays. This cellular background provides a clinically relevant context for studying gene function in osteosarcoma biology.
EIF2AK2 encodes protein kinase R (PKR), a critical innate immune sensor that responds to dsRNA and interferon signaling. Upon activation, PKR autophosphorylates and then phosphorylates eIF2??, inhibiting cap-dependent translation and promoting stress granule formation. This triggers the integrated stress response, upregulating ATF4 and CHOP to drive apoptosis. PKR additionally activates NF-??B through IKK complex engagement and stimulates MAP kinase pathways, promoting pro-inflammatory gene expression. Key regulators include interferons (IFN-??/??/??), dsRNA, and protein partners PACT/PRKRA and TRBP/TARBP2. Downstream effectors include phosphorylated eIF2??, ATF4, CHOP, NFKBIA/I??B??, and components of the antiviral and apoptotic machinery.
In osteosarcoma, PKR signaling integrates stress and immune signals that influence cell fate. The EIF2AK2 knockout in 143B cells allows examination of how loss of PKR alters translational control, apoptosis, and NF-??B-mediated inflammatory responses in a bone tumor context. This model is valuable for probing PKR??s contribution to chemotherapy resistance, tumor cell survival under hypoxia, and immunogenic signaling. It also provides insight into the interplay between viral mimicry pathways and oncogenic stress in sarcoma.
Research applications encompass antiviral innate immunity studies using dsRNA transfection followed by RT-qPCR for interferon-stimulated genes, apoptosis assays with Annexin V/PI, and Western blotting for phospho-eIF2?? and downstream markers. The polyclonal knockout pool is suited for NF-??B luciferase reporter assays, polysome profiling for translation analysis, and co-immunoprecipitation of PKR interactors such as PACT and ADAR1. It further enables drug screening for PKR modulators in a cancer-relevant background. For further details, please contact Ascent Research.
