The GSTM1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-engineered polyclonal knockout cell population derived from the near-haploid HAP1 cell line, designed to disrupt the GSTM1 gene. This product provides a heterogeneous pool of edited cells, enabling robust loss-of-function analyses without the biases associated with single-cell cloning.
The HAP1 cell line is a chronic myelogenous leukemia-derived near-haploid human line originating from KBM-7 cells. Its near-haploid karyotype simplifies genetic knockout studies, as disruption of a single allele often leads to a null phenotype. HAP1 cells are widely used in functional genomics and targeted gene knockout screens, offering a consistent and interpretable genetic background for investigating detoxification pathways.
GSTM1 encodes a glutathione S-transferase that catalyzes the conjugation of reduced glutathione to electrophilic xenobiotics and oxidative stress by-products, facilitating their excretion. Transcription of GSTM1 is regulated by NFE2L2 (Nrf2) via antioxidant response elements and by the aryl hydrocarbon receptor (AhR). GSTM1 interacts with MAP3K5 (ASK1) and other glutathione S-transferases, and operates within the glutathione metabolism and cytochrome P450 detoxification networks. In these pathways, it acts downstream of NFE2L2/KEAP1 sensing and contributes to the elimination of genotoxicants and chemotherapeutic agents.
Loss of GSTM1 in HAP1 cells impairs glutathione-dependent detoxification, rendering the cells more susceptible to oxidative stress and electrophilic damage. The near-haploid state ensures that knockout phenotypes are not masked by a wild-type allele, while the polyclonal nature may mirror the functional heterogeneity of GSTM1 polymorphisms in human populations, including common null alleles. This model is thus valuable for investigating gene-environment interactions and pharmacogenetic susceptibility.
Key research applications include toxicology screening, assessment of chemotherapy resistance, oxidative stress biology, and drug metabolism studies. Validation assays typically involve immunoblotting and RT-qPCR for GSTM1 expression, enzymatic activity measurements, and viability challenges with H2O2 or drugs such as cisplatin and acetaminophen. Additional endpoints include comet assays for DNA damage and flow cytometry for reactive oxygen species. This model supports mechanistic studies of detoxification pathways and drug-induced toxicity. Contact Ascent Research for additional technical information.
