The HERPUD2 Knockout A-549 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population in which the HERPUD2 gene has been disrupted to ablate functional protein expression. This heterogeneous pool avoids clonal selection artifacts, offering a more representative model for studying ER stress responses. The stable disruption enables long-term investigations of ER-associated degradation (ERAD) and the unfolded protein response (UPR).
The A-549 cell line is a widely used human lung adenocarcinoma model derived from a male patient, characterized by KRAS mutations and employed extensively in cancer biology and drug discovery. These epithelial cells possess high secretory activity and are inherently sensitive to ER stress perturbations, making them a suitable host for examining proteostatic regulation within an oncogenic background.
HERPUD2 encodes an ER membrane protein that senses misfolded protein accumulation and is transcriptionally induced by ATF6 and IRE1??/XBP1. It interacts with ERAD core components HRD1, SEL1L, OS9, VIMP, and DERL1 to facilitate retrotranslocation of aberrant substrates for proteasomal degradation. Functioning downstream of IRE1??, PERK, and ATF6, HERPUD2 modulates UPR signaling by promoting clearance of misfolded clients, thereby dampening pro-apoptotic CHOP induction and ATF4-mediated transcription. Loss of HERPUD2 impairs ERAD efficiency, leading to sustained UPR activation and increased sensitivity to ER stress-induced apoptosis.
In lung adenocarcinoma cells, loss of HERPUD2 compromises ERAD machinery, leading to persistent UPR activation that can shift cellular fate toward apoptosis under chronic stress. This knockout model facilitates exploration of how cancer cells adapt to proteotoxic insults and provides a platform for evaluating drug sensitivity to ER stress-inducing agents such as thapsigargin or bortezomib. The polyclonal approach ensures population-level insights into UPR dynamics.
Typical applications include Western blotting for UPR markers (e.g., BiP, CHOP, ATF4), RT-qPCR for XBP1 splicing, fluorometric proteasomal activity assays, Annexin V apoptosis measurements, and cell viability tests under ER stress inducers. Immunofluorescence can monitor ER morphology and localization of interacting partners like HRD1 or SEL1L. The cells are also suited for high-throughput screens identifying modulators of the ERAD-UPR axis. For further details, please contact Ascent Research.
