The EIF2AK2 Knockout HEK293 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal population of HEK293 cells carrying a targeted disruption of the EIF2AK2 gene, which encodes protein kinase R (PKR). This loss-of-function model eliminates functional PKR, enabling dissection of dsRNA-activated antiviral and stress signaling without propagation of single-cell clones. The polyclonal format provides population-level genetic heterogeneity for robust phenotypic assays.
The parental HEK293 line is an immortalized human embryonic kidney epithelial cell that constitutively expresses adenovirus 5 E1A and E1B proteins, facilitating continuous growth and high transfectability. HEK293 cells exhibit low basal interferon pathway activity, making them a preferred platform for studying exogenous interferon responses, viral replication, and translational control mechanisms in a consistent and experimentally tractable system.
EIF2AK2/PKR is an interferon-inducible kinase activated by double-stranded RNA (dsRNA) and protein cofactors such as PACT (PRKRA). Upon activation, PKR phosphorylates eIF2?? (EIF2S1) at Ser51, inhibiting global cap-dependent translation while permitting selective translation of stress-responsive mRNAs, including the transcription factor ATF4. This triggers the integrated stress response (ISR) and upregulates CHOP (DDIT3) and GADD34 (PPP1R15A). Under persistent stress, PKR engages NF-kappaB signaling and the FADD/caspase-8 pathway to promote apoptosis. PKR interacts with TARBP2, the endogenous inhibitor p58IPK (DNAJC3), and viral modulators such as adenovirus VAI RNA. This positions PKR as a critical node connecting dsRNA sensing, translational reprogramming, and cell fate decisions.
In HEK293 cells, EIF2AK2 knockout removes the dominant dsRNA-responsive kinase, allowing precise analysis of alternative innate immune pathways and stress granule dynamics without PKR-mediated eIF2?? phosphorylation. Since HEK293 cells express adenoviral factors like VAI RNA that naturally inhibit PKR, this knockout model resolves host-viral antagonism and enables functional reconstitution experiments using ectopic PKR variants. It is particularly useful for decoupling PKR-dependent and -independent interferon effects.
Key applications include antiviral innate immunity studies, translation regulation profiling, apoptosis mechanism elucidation, and cancer target validation. Assay examples: eIF2?? phosphorylation western blot, polysome profiling, ATF4/CHOP qPCR, ISR luciferase reporter, viral replication assays, cleaved caspase-3 immunofluorescence, and NF-kappaB reporter assays. For further information, please contact Ascent Research.
