The GSTK1 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma cell line. This product provides a loss-of-function model for the GSTK1 gene, which encodes a mitochondrial and peroxisomal glutathione S-transferase. The polyclonal format allows researchers to study GSTK1 function without single-cell clone artifacts, making it suitable for pooled genetic screens and population-level phenotypic analyses.
The HT29 cell line is a widely used model of colorectal adenocarcinoma, originally established from a 44-year-old female patient. It harbors a mutant TP53 gene, reflecting the p53 abnormalities common in colon cancer. HT29 cells exhibit an intestinal epithelial phenotype and can form polarized monolayers or spheroids, making them valuable for investigating colorectal cancer biology, epithelial barrier function, and drug transport. This host cell background provides a clinically relevant context for studying GSTK1 in colon adenocarcinoma.
GSTK1 is uniquely localized to mitochondria and peroxisomes, where it catalyzes the conjugation of reduced glutathione (GSH) to electrophilic compounds, including xenobiotics and lipid peroxidation products. This activity protects these organelles from oxidative damage. Transcription of GSTK1 is activated by NRF2 in response to oxidative stress and is modulated by PPAR?? and PPAR??. GSTK1 interacts directly with GSH and peroxisomal proteins, and functions within a detoxification network that includes glutathione reductase (GSR), glutathione peroxidase (GPX), and the multidrug resistance protein MRP1/ABCC1. NADPH provides reducing power for glutathione recycling, maintaining cellular redox balance.
In HT29 colorectal adenocarcinoma cells, GSTK1 knockout creates a system to examine how loss of organelle-specific detoxification influences cancer cell fitness. The mutant TP53 status of HT29 is known to disrupt redox regulation, making this model especially pertinent for exploring the interplay between GSTK1-mediated glutathione conjugation and p53-dependent stress responses. Disruption of GSTK1 may compromise mitochondrial and peroxisomal integrity, leading to increased sensitivity to oxidative insults and chemotherapeutic agents. This model supports studies of adaptive resistance and synthetic lethal interactions in colon cancer.
Researchers can apply this GSTK1 knockout polyclonal population in a broad array of experimental workflows. Standard molecular characterization includes Western blot and RT-qPCR for GSTK1 and related genes. Functional analyses may involve glutathione S-transferase activity assays and cell viability testing under oxidant challenge (e.g., H?O? treatment). Chemosensitivity can be evaluated using MTT or similar assays, while flow cytometry quantifies intracellular reactive oxygen species. Immunofluorescence and subcellular fractionation assess mitochondrial and peroxisomal status. Transcriptomic approaches such as RNA-seq reveal pathway adaptations. This model is well-suited for research in colorectal cancer biology, oxidative stress, drug resistance, and peroxisomal disorders. For further details, please contact Ascent Research.
