The GSR Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population from the human HT29 colorectal adenocarcinoma line. This product features targeted disruption of the GSR gene, encoding glutathione reductase, providing a loss-of-function model for investigating redox homeostasis and oxidative stress signaling. The polyclonal format captures a heterogeneous edited population, enabling robust gene function assessment without clonal bias.
HT29 cells are adherent epithelial cells from a primary colon adenocarcinoma of a female patient. They are widely used as a model for intestinal epithelial biology, colorectal cancer progression, drug absorption, and metastasis, retaining characteristics of differentiated intestinal epithelium suitable for barrier function and drug response studies.
GSR encodes glutathione reductase, which reduces glutathione disulfide (GSSG) to glutathione (GSH) using NADPH, maintaining cellular redox balance. The enzyme is a critical component of the glutathione redox cycle, transcriptionally regulated by NRF2 through KEAP1 sensing, and functions downstream of NRF2 and upstream of glutathione peroxidases GPX1 and GPX4, interacting with GSSG, NADPH, and FAD. GSR disruption leads to GSSG accumulation, GSH depletion, impaired antioxidant defense, and heightened sensitivity to oxidative stress and ferroptosis?? lipid peroxidation-driven non-apoptotic death.
In HT29 cells, GSR is pivotal for redox homeostasis and survival under high oxidative load, such as during proliferation or chemotherapy. GSR knockout disrupts the glutathione-dependent antioxidant network, potentially enhancing ferroptosis sensitivity and oxidative stress. This model is relevant for chemoresistance studies, as colorectal cancer cells often rely on GSH to mitigate ROS and evade drug cytotoxicity.
Researchers can use these cells to study redox regulation and ferroptosis by performing GSH/GSSG ratio assays, Western blotting for GPX4 and NRF2, and RT-qPCR of antioxidant genes. Functional assays include viability under oxidative stress (H2O2, erastin), lipid ROS detection with Liproxstatin-1 rescue, flow ROS measurement, clonogenic survival, and NADP/NADPH quantification. These enable dissection of oxidative stress, cell death, and cancer biology. For further information, contact Ascent Research.
