The GSS Knockout HAP1 Polyclonal Cells product comprises a CRISPR/Cas9-edited polyclonal knockout cell population targeting the human GSS gene in the HAP1 cell background. This loss-of-function model enables interrogation of glutathione synthetase function without relying on isolated clonal lines, preserving population-level heterogeneity. The polyclonal knockout format is generated through CRISPR/Cas9-mediated gene disruption, creating a versatile tool for pooled functional genomics and pathway analysis.
HAP1 is a near-haploid human cell line derived from a male patient with chronic myeloid leukemia. Its largely haploid karyotype simplifies genetic manipulation and phenotypic interpretation, making it a preferred system for knockout screens and mechanistic studies. As a suspension-adapted line, HAP1 cells facilitate scalable culture and high-throughput assays, and their chronic myeloid leukemia origin provides a relevant context for redox biology investigations.
Glutathione synthetase (GSS) catalyzes the ATP-dependent ligation of ??-glutamylcysteine and glycine to form glutathione (GSH), the rate-limiting step in de novo GSH biosynthesis. GSS expression is transcriptionally regulated by NFE2L2 (NRF2) and ATF4, key stress-responsive factors, and functions downstream of glutamate-cysteine ligase (GCL). In the glutathione metabolism pathway, GSS-generated GSH serves as a cofactor for glutathione peroxidase 4 (GPX4), which directly reduces lipid peroxides and suppresses ferroptosis. Thus, GSS sits at a critical node connecting upstream redox-sensing transcription factors to downstream antioxidant defense proteins such as GPX4 and SLC7A11.
In the HAP1 background, disruption of GSS depletes intracellular GSH pools, perturbing redox homeostasis and sensitizing cells to oxidative stress and ferroptotic stimuli. Because HAP1 cells possess a near-haploid genome, the knockout population exhibits uniform loss-of-function phenotypes, enabling robust study of GSS-dependent metabolic vulnerabilities. This model is especially suited for dissecting ferroptosis mechanisms, as GSS deficiency mimics conditions that lower GSH and compromise GPX4 activity, a central ferroptosis regulator.
Researchers can utilize these polyclonal knockout cells in a variety of experimental designs. Typical applications include measuring GSH/GSSH ratios, detecting reactive oxygen species (ROS) via flow cytometry, performing ferroptosis induction and rescue assays, assessing cell viability under oxidative challenge, and conducting western blotting for GPX4 and SLC7A11. Further metabolomic profiling and GSS enzymatic activity assays can validate pathway alterations. This product enables mechanistic studies in oxidative stress response, drug resistance, and neurodegenerative and cancer models. For further information, please contact Ascent Research.
