The APTX Knockout Jurkat Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population engineered to disrupt the APTX gene in the Jurkat T-cell leukemia line. This pooled population provides a loss-of-function model of aprataxin, a critical enzyme in DNA single-strand break repair. The polyclonal format preserves a spectrum of CRISPR-induced gene disruptions, enabling the study of APTX-dependent phenotypes without clonal selection bias. The cells are suitable for experiments requiring robust cellular models of DNA repair deficiency and have been quality-controlled for viability and identity.
Jurkat cells are a well-established immortalized T-lymphocyte line derived from a patient with acute T-cell leukemia. They serve as a versatile model for T-cell receptor signaling, activation, apoptosis, and hematological malignancy research. Their suspension growth and reliable response to a range of stimuli make them a favorite for high-throughput screening and mechanistic studies. The Jurkat background is especially relevant for studying the interplay between DNA repair pathways and lymphocyte physiology, as lymphoid cells are subject to high replicative stress and genomic rearrangements.
Aprataxin, encoded by APTX, functions as a 5??-AMP deadenylase that resolves abortive DNA ligation intermediates generated during single-strand break repair (SSBR). In the SSBR pathway, APTX interacts with XRCC1, DNA ligase III??, PNKP, PARP1, and DNA polymerase ?? to remove obstructive 5??-adenylated lesions from DNA termini, thereby facilitating ligation and maintaining genomic integrity. APTX is activated by oxidative stress and DNA damage signaling through ATM/ATR kinases, and its deficiency results in persistent DNA strand breaks, hypersensitivity to genotoxic agents, and compromised cellular survival. The accumulation of unrepaired damage is a central driver of neurodegeneration observed in ataxia-oculomotor apraxia type 1.
In Jurkat T cells, loss of APTX disrupts the SSBR machinery, leading to elevated baseline DNA damage and increased susceptibility to oxidative stress. This is particularly relevant because T lymphocytes experience high levels of metabolic and proliferative stress. The knockout model enables dissection of how DNA repair defects influence T-cell activation, cytokine production, and apoptosis. When challenged with DNA-damaging agents such as etoposide or H2O2, APTX-deficient Jurkat cells exhibit reduced viability and amplified DNA damage responses, as measured by ??H2AX foci and comet assays. This system also allows investigation of compensatory repair pathways and the role of PARP1-mediated signaling in APTX-null backgrounds.
This APTX knockout tool is suited for a range of applications, including high-content screens for modulators of single-strand break repair, drug sensitivity profiling with topoisomerase inhibitors or alkylating agents, and mechanistic studies of ataxia-related neurodegeneration. The cells can be used in T-cell activation assays (NFAT reporter, IL-2 secretion) to probe the connection between genome integrity and immune function. Additionally, they serve as a host for exploring synthetic lethal interactions with PARP inhibitors or other DNA repair-targeted agents. Researchers can pair this model with ??H2AX immunofluorescence, western blotting for DNA damage markers, and RT-qPCR to validate APTX disruption. For further details or custom requests, please contact Ascent Research.
