The GSR Knouckout A-549 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population from human A-549 cells, designed to disrupt the GSR gene. This loss-of-function model abolishes glutathione-disulfide reductase (GSR) activity, impairing reduction of glutathione disulfide (GSSG) to glutathione (GSH). The polyclonal format avoids clonal bias, reflecting population-level gene disruption suitable for robust phenotypic screening.
The parental A-549 cell line is a well-established model of human lung adenocarcinoma, derived from alveolar basal epithelial cells of a 58-year-old male. These cells retain key epithelial characteristics and are widely used for studying oxidative stress, apoptosis, and drug resistance mechanisms. Their well-documented signaling profiles provide a reliable background for probing redox-dependent phenotypes.
GSR functions as a central enzyme in glutathione metabolism, catalyzing NADPH-dependent reduction of GSSG to GSH. This reaction sustains cellular antioxidant capacity and thiol-redox balance. Transcription of GSR is activated by Nrf2 and AP-1 under oxidative stress, while its enzymatic product, GSH, feeds back to regulate ROS detoxification and antioxidant response element (ARE)-driven genes. GSR interacts directly with GSSG and NADPH, and it operates in concert with thioredoxin, glutathione peroxidase (GPX), glutaredoxin (GRX), glutathione S-transferase (GST), and glutamate-cysteine ligase (GCL). Knockout of GSR therefore disrupts this multi-enzyme network, leading to elevated ROS and compromised redox homeostasis.
In A-549 lung cancer cells, GSR disruption is particularly impactful because malignant cells often upregulate glutathione-dependent defenses to counteract high intrinsic oxidative stress and survive cytotoxic therapies. Loss of GSR sensitizes these cells to oxidative damage and apoptotic death, offering a valuable tool for investigating redox adaptation, drug resistance, and Nrf2-mediated survival pathways. The model facilitates identification of synthetic lethal interactions and tumor-suppressive redox signaling nodes.
Key applications include glutathione quantification, detection of reactive oxygen species, western blot analysis of GSR and pathway regulators, and cell viability assays under oxidative challenge. This model also supports metabolomic profiling, NADPH/NADP+ ratio determination, and antioxidant screening. It is ideally suited for advancing research in lung cancer redox biology and chemoresistance. For additional information, please contact Ascent Research.
