The EIF2AK3 Knockout AGS Polyclonal Cells product constitutes a CRISPR/Cas9-edited polyclonal knockout population derived from the AGS human gastric adenocarcinoma cell line, offering a loss-of-function model for the ER stress sensor kinase PERK. CRISPR/Cas9-mediated disruption of EIF2AK3 eliminates functional PERK protein expression, enabling dissection of its role in the unfolded protein response (UPR) within an epithelial gastric cancer context. The polyclonal nature preserves genetic heterogeneity, providing a robust tool for studying PERK-dependent signaling without clonal selection bias.
AGS cells originate from a gastric adenocarcinoma biopsy and serve as a widely used epithelial model of human gastric cancer. These cells display characteristic features of gastric tumor epithelium and are extensively characterized for investigations into proliferation, invasion, drug sensitivity, and cellular stress responses, making them relevant for examining interactions between oncogenic pathways and the integrated stress response.
EIF2AK3 encodes PERK, a type I transmembrane kinase resident in the ER membrane. Under non-stress conditions, PERK is held inactive through binding to the chaperone GRP78/BiP; upon accumulation of misfolded proteins, BiP dissociates, enabling PERK dimerization and autophosphorylation, which constitutes the activation step. Active PERK directly phosphorylates eIF2?? at serine 51, attenuating general cap-dependent translation while paradoxically enhancing translation of ATF4 mRNA via upstream open reading frames. ATF4 acts as a transcription factor that upregulates genes encoding CHOP/DDIT3, GADD34/PPP1R15A, and other stress-responsive proteins. CHOP in turn promotes apoptosis by modulating BCL2 family members such as BIM and PUMA, whereas GADD34 provides negative feedback by recruiting protein phosphatase 1 to dephosphorylate eIF2??, restoring translation. Additionally, PERK phosphorylates NRF2, contributing to antioxidant gene expression, and interacts with IRE1 and P58IPK to coordinate the broader UPR network. This signaling cassette couples ER protein-folding status to translational control and cell survival/death decisions.
In gastric cancer, PERK-mediated signaling contributes to tumor cell adaptation to the harsh microenvironment, chemoresistance, and apoptosis regulation. PERK activation is often observed in solid tumors, including gastric adenocarcinoma, where it supports adaptation to nutrient deprivation and hypoxia. The EIF2AK3 Knockout AGS Polyclonal Cells therefore provide a physiologically relevant platform to dissect PERK function in AGS cell survival under ER stress, assess modulation of downstream effectors such as ATF4 and CHOP, and explore crosstalk with other UPR pathways in a gastric epithelial context.
These knockout cells are suitable for western blot analysis of phospho-eIF2?? and ATF4, RT-qPCR quantification of CHOP and GADD34 induction after tunicamycin treatment, and apoptosis assays by Annexin V flow cytometry. Additional applications include cell viability studies with UPR modulators and immunofluorescence localization of PERK. This model supports research on UPR signaling, therapeutic target validation, and drug resistance mechanisms in gastric cancer. For further information, please contact Ascent Research.
