The EIF2A Knockout NCI-H1299 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the NCI-H1299 cell line, engineered to disrupt the EIF2A gene. This product provides a heterogeneous mixture of cells harboring targeted mutations, enabling loss-of-function studies of EIF2A in a lung adenocarcinoma background.
The parental NCI-H1299 cell line is a widely used in vitro model for non-small cell lung cancer (NSCLC), originating from lymph node metastasis of a lung adenocarcinoma from a 43-year-old male. These cells lack functional p53, a critical tumor suppressor, making them particularly valuable for studying p53-independent oncogenic mechanisms and therapeutic vulnerabilities.
EIF2A encodes the alpha subunit of the eukaryotic initiation factor 2 (eIF2) complex, a central regulator of protein synthesis. It assembles with GTP and initiator Methionine-tRNA (Met-tRNAi) to form the eIF2-GTP-Met-tRNAi ternary complex, which binds to the 40S ribosomal subunit, facilitating 43S preinitiation complex formation. EIF2A activity is tightly controlled by phosphorylation at Ser51 by stress-responsive kinases EIF2AK1/HRI, EIF2AK2/PKR, EIF2AK3/PERK, and EIF2AK4/GCN2. Phosphorylated EIF2A sequesters the guanine nucleotide exchange factor eIF2B, inhibiting GDP/GTP exchange and thereby attenuating global cap-dependent translation. Concomitantly, this stress response selectively upregulates translation of ATF4, a transcription factor that orchestrates adaptive gene expression programs. EIF2A also interfaces with mTORC1 signaling and interacts with eIF5 and the 40S ribosomal subunit.
In the NCI-H1299 NSCLC model, disruption of EIF2A provides a powerful tool to dissect the role of translational reprogramming in lung adenocarcinoma. Given the p53 deficiency, these cells may rely on alternative stress response pathways for survival, making EIF2A-mediated regulation of the integrated stress response and ATF4 induction particularly relevant. This knockout model enables investigation of how cancer cells adapt to microenvironmental stresses such as nutrient deprivation and hypoxia, which are known to activate EIF2A kinases. Moreover, it allows assessment of EIF2A-dependent translational control in regulating proliferation, apoptosis, and drug sensitivity in a therapeutically challenging cancer context.
Researchers can employ these polyclonal knockout cells to study EIF2A-dependent translational control mechanisms in NSCLC. Specific applications include assessing global protein synthesis rates via puromycin incorporation or polysome profiling, comparing cap-dependent versus IRES-mediated translation using dual-luciferase reporters, and evaluating cell viability under conditions that induce EIF2A phosphorylation, such as amino acid deprivation or ER stress. The cells are also suitable for investigating the crosstalk between the integrated stress response and mTOR signaling, as well as screening for modulators of ATF4 expression. For further technical details, please contact Ascent Research.
