The EIF2AK4 Knockout HCT 116 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population designed for loss-of-function studies of the EIF2AK4 gene (also known as GCN2) in a human epithelial colorectal carcinoma background. This product comprises a heterogeneous pool of HCT 116 cells carrying diverse disruptions in the EIF2AK4 locus, generated by non-clonal selection after CRISPR/Cas9-mediated gene targeting. As a polyclonal population, it mitigates clonal artifacts and provides a robust model system for interrogating gene function under biologically relevant, mixed genotypes.
The parental HCT 116 cell line is a well-characterized human colorectal carcinoma model with deficient DNA mismatch repair (MLH1 deficiency), widely employed in cancer biology, drug development, and stress response studies. Derived from a male patient with colorectal adenocarcinoma, these epithelial cells retain key signaling pathways relevant to tumor progression, nutrient sensing, and therapeutic resistance. The MLH1-deficient background makes HCT 116 particularly valuable for investigating genetic interactions and the impact of specific gene disruptions in a mismatch repair-defective context.
EIF2AK4 encodes GCN2, a serine/threonine kinase that functions as a central sensor of amino acid deprivation and other cellular stresses. GCN2 is activated by uncharged tRNAs accumulating during amino acid starvation, an interaction facilitated by the GCN1-GCN20 complex, leading to phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2??) on Ser51. This phosphorylation attenuates global mRNA translation while selectively enhancing the translation of ATF4, a key transcription factor that induces downstream targets such as CHOP (DDIT3), REDD1 (DDIT4), and SLC7A11. Through this integrated stress response (ISR), GCN2 coordinates adaptive programs, including amino acid biosynthesis, autophagy, mTOR signaling modulation, and, under severe or prolonged stress, apoptosis.
In HCT 116 colorectal cancer cells, GCN2-dependent signaling is implicated in sustaining cell survival during nutrient fluctuations inherent to the tumor microenvironment. By coupling amino acid availability to translational control and ATF4-driven transcription, GCN2 may promote metabolic reprogramming, redox homeostasis, and resistance to chemotherapeutic agents. Disruption of EIF2AK4 in this cellular context provides a powerful tool for dissecting how colorectal cancer cells adapt to amino acid stress, regulate autophagy, and evade apoptosis, offering insights into metabolic vulnerabilities and potential therapeutic targets.
This polyclonal knockout pool is suited for a wide range of experimental workflows, including amino acid starvation assays, cell viability and colony formation assays under nutrient stress, and xenograft tumor growth analyses to evaluate the role of GCN2 in tumorigenesis. Researchers can employ western blotting to monitor p-eIF2?? (Ser51) and ATF4 protein levels, RT-qPCR for ATF4 target gene expression, polysome profiling to assess global translation changes, and RNA-seq for comprehensive translational profiling. These cells are compatible with functional rescue experiments and combinatorial studies with mTOR inhibitors or autophagy modulators. For additional product information and technical support, please contact Ascent Research.
