APTX Polyclonal Knockout HeLa Cells are a CRISPR/Cas9-edited polyclonal population derived from HeLa cells, in which the APTX gene has been disrupted to create a loss-of-function model. This polyclonal knockout cell population provides a heterogeneous pool of edited alleles, enabling functional studies of APTX within a cancer-relevant genomic context. The targeted gene disruption abolishes APTX protein expression, allowing investigators to dissect its role in DNA repair pathways and cellular responses to DNA damage.
The parental HeLa cell line is a widely used human cervical adenocarcinoma model, characterized by HPV-18 positivity and p53 deficiency. This genetic background renders the cells particularly susceptible to genomic instability, making it an ideal host for examining DNA repair deficiencies. The p53-deficient status means that the G1/S checkpoint is compromised, so cells rely heavily on intact DNA repair mechanisms for survival, thereby accentuating the effects of APTX loss.
APTX (Aprataxin) functions in the base excision repair and single-strand break repair (SSBR) pathways by resolving abortive DNA ligation intermediates. Specifically, APTX removes 5??-AMP groups from DNA ends, a necessary step for completing ligation and maintaining genomic integrity. APTX is activated by ATM and ATR kinases and works in concert with XRCC1, DNA ligase III, PARP1, and DNA polymerase ??. It is recruited to sites of damage and interacts with these core repair factors to facilitate efficient repair. Disruption of APTX leads to accumulation of unrepaired single-strand breaks and triggers DNA damage signaling.
In the HeLa cell context, loss of APTX function significantly impairs SSBR capacity, leading to increased DNA damage accumulation and heightened sensitivity to genotoxic agents. This knockout model recapitulates key molecular phenotypes observed in Ataxia with Oculomotor Apraxia Type 1 (AOA1), a neurodegenerative disorder caused by APTX mutations. Moreover, because HeLa cells are p53-deficient, the APTX knockout model exhibits exacerbated genomic instability and may serve as a potent tool for studying synthetic lethality interactions and cancer drug sensitization.
Research applications for this product include investigating DNA repair mechanisms, particularly SSBR and base excision repair, using assays such as Western blotting to confirm loss of APTX, immunofluorescence for ??H2AX foci to monitor DNA damage, comet assays to assess DNA strand breaks, and co-immunoprecipitation to study protein interactions. The polyclonal knockout cells are also valuable for cancer drug sensitization studies, where APTX deficiency can be exploited to increase sensitivity to DNA-damaging chemotherapeutics or PARP inhibitors. Additionally, they provide a cell culture model for AOA1 neurodegeneration research. For more information or to discuss your specific research needs, please contact Ascent Research.
