The CAT Knockout HeLa Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population engineered to disrupt the CAT gene in the human HeLa cell line. This loss-of-function model eliminates catalase expression, the primary enzyme responsible for decomposing hydrogen peroxide into water and oxygen. The heterogeneous population provides a physiologically relevant system for studying oxidative stress responses without clonal selection artifacts, enabling robust analysis of hydrogen peroxide-mediated signaling pathways and antioxidant defense mechanisms.
HeLa cells are a widely utilized human epithelial cell line derived from a cervical adenocarcinoma, known for their HPV18-positive status and robust growth characteristics. As a model of cancer cell biology, HeLa cells exhibit altered redox homeostasis, making them particularly suitable for investigating the consequences of catalase deficiency. This host background facilitates the examination of oxidative stress in a transformed cellular environment, where reactive oxygen species (ROS) play critical roles in proliferation, apoptosis, and therapeutic resistance.
Catalase functions downstream of key oxidative stress regulators including the transcription factor NFE2L2 (Nrf2), FOXO3, PPARG, and HIF1A, and its expression is modulated by stimuli such as hydrogen peroxide and TNF-??. In the knockout context, loss of CAT disrupts hydrogen peroxide catabolism, leading to accumulation of intracellular H2O2. This elevates oxidative stress, promoting protein carbonylation and lipid peroxidation, and activates redox-sensitive cascades like MAPK and NF-??B. Catalase collaborates with SOD1, GPX1, and PRDX1, and requires PEX5 for peroxisomal import, integrating into a network where SOD1 converts superoxide to H2O2, which is then detoxified by CAT or GPX1, with NFE2L2 serving as a master regulator through KEAP1-mediated sensing.
In the HeLa cancer cell model, CAT knockout accentuates the intrinsic oxidative burden, providing a powerful tool to study tumor cell adaptation to oxidative microenvironments. Elevated hydrogen peroxide levels can drive genomic instability, modulate proliferation, and influence sensitivity to chemotherapeutic agents. This model is particularly relevant for research into acatalasemia, diabetes mellitus, vitiligo, and cancer, where catalase dysfunction or oxidative stress plays a pathogenic role. By uncoupling antioxidant capacity, researchers can dissect the contribution of catalase to cellular survival under pathophysiological conditions.
Researchers can employ this knockout model for diverse applications including quantitative H2O2 measurement via Amplex Red, ROS detection with DCFDA, and catalase activity assays to confirm disruption. Viability assays under hydrogen peroxide challenge, lipid peroxidation assessment by TBARS, DNA damage analysis using comet assays, and apoptosis detection with Annexin V staining enable mechanistic studies of oxidative stress responses. Transcriptome-wide RNA-seq and targeted gene expression analysis by RT-qPCR further elucidate redox-sensitive transcriptional programs. This model is instrumental for investigations into drug resistance, cellular senescence, and antioxidant defense. For additional information or to discuss your specific research needs, please contact Ascent Research.
