The GSTA4 Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-mediated gene disruption model targeting the GSTA4 locus. This polyclonal knockout population, generated in the HAP1 cell line, offers a heterogeneous collection of cells with loss-of-function mutations in GSTA4, enabling functional studies of glutathione S-transferase alpha 4 without clonal selection. The product is designed for researchers investigating oxidative stress and detoxification pathways, providing a robust tool for genetic screening and pathway analysis.
The HAP1 cell line is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia (CML) background. Its haploid karyotype facilitates efficient CRISPR/Cas9-mediated gene disruption and makes it a widely used model for genetic knockout studies and high-throughput functional genomics. HAP1 cells retain leukemic properties, making them relevant for studying pathways involved in leukemia biology, including oxidative stress responses and drug resistance mechanisms.
GSTA4 encodes glutathione S-transferase alpha 4, a critical enzyme in the detoxification of electrophilic compounds. Mechanistically, GSTA4 catalyzes the conjugation of reduced glutathione to reactive aldehydes, particularly the lipid peroxidation product 4-hydroxynonenal (4-HNE). This reaction neutralizes toxic lipid peroxides and modulates signaling cascades influenced by reactive aldehyde species. GSTA4 expression is transcriptionally regulated by NRF2 (NFE2L2) and the aryl hydrocarbon receptor (AHR) downstream of oxidative stress and electrophilic stimuli. The enzyme interacts with glutathione and 4-HNE, and its activity indirectly affects JNK signaling through the formation of 4-HNE adducts. Downstream, GSTA4 reduces 4-HNE-mediated modulation of NF-??B signaling and limits lipid peroxidation, thus protecting cells from oxidative damage. Representative pathway components include KEAP1, NRF2, GSTA4, glutathione, 4-HNE, and NADPH, highlighting its role in the cellular oxidative stress response.
In the context of HAP1 leukemia cells, GSTA4 disruption is particularly significant for understanding how leukemic cells handle oxidative stress. Chronic myeloid leukemia cells often exhibit altered redox homeostasis, and GSTA4-mediated detoxification of 4-HNE may contribute to chemoresistance by reducing drug-induced lipid peroxidation. The polyclonal knockout model allows for the study of GSTA4 loss in a heterogeneous population, mirroring the genetic variability seen in tumor environments. Researchers can investigate how loss of GSTA4 sensitizes leukemia cells to oxidative stress-inducing agents or alters signaling through NRF2-dependent pathways, providing insights into potential therapeutic vulnerabilities.
This knockout model is suitable for a wide range of experimental applications, including oxidative stress response studies, drug metabolism and detoxification research, and investigation of lipid peroxidation in cancer biology. Common assays performed with these cells include western blotting to assess protein expression, GST activity assays using substrates like CDNB or 4-HNE, cell viability and apoptosis assays under oxidative stress conditions, RT-qPCR for gene expression analysis, and flow cytometry to measure reactive oxygen species levels. The polyclonal nature of the knockout population supports unbiased functional genomics screens and pathway dissection. For further information, contact Ascent Research.
