The HLTF Knockout HeLa Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HeLa cell line, designed for the disruption of the HLTF gene. This product provides a heterogeneous pool of edited cells, enabling functional studies of HLTF without clonal isolation. The knockout model serves as a loss-of-function system to investigate HLTF-dependent mechanisms in DNA repair, replication stress, and genomic stability, and is suitable for a broad range of biomedical research applications.
The host cell line, HeLa, is an immortalized human epithelial cell line originating from cervical adenocarcinoma and is positive for human papillomavirus 18 (HPV18). HeLa cells are one of the most widely used models in cell biology and cancer research due to their robust growth, ease of manipulation, and well-characterized genomic landscape. Their transformed phenotype and inherent genomic instability make them particularly relevant for studying DNA damage responses and tumor suppression mechanisms.
HLTF (helicase-like transcription factor) is a dual-function DNA helicase and E3 ubiquitin ligase that plays a critical role in the DNA damage response and replication fork remodeling. It is activated upstream by DNA damage signaling kinases ATM and ATR and transcriptionally regulated by E2F1. HLTF recognizes stalled replication forks via its HIRAN domain, promotes fork reversal, and polyubiquitinates proliferating cell nuclear antigen (PCNA) to facilitate error-free lesion bypass. It interacts directly with PCNA, RAD51, SHPRH, and UBE2N, and functions within the Fanconi anemia pathway and homologous recombination repair. Downstream effects include modulation of RAD51 foci formation and chromatin remodeling at damaged sites.
In the HeLa background, HLTF knockout allows dissection of replication stress responses in a cancer-relevant context. The HPV18 oncoproteins E6 and E7 disrupt p53 and Rb pathways, respectively, creating a permissive environment for genomic instability. Loss of HLTF in this setting can exacerbate replication fork stalling, impair homologous recombination, and increase sensitivity to DNA-damaging agents, providing a powerful model to study tumor suppression and helicase-deficiency disorders. This system is especially valuable for exploring synthetic lethal interactions with cancer therapies.
Researchers can employ these polyclonal knockout cells for a variety of applications, including Western blotting to assess HLTF protein levels and PCNA ubiquitination, immunofluorescence to quantify ??-H2AX and RAD51 foci as markers of DNA damage and repair, and Comet assays to evaluate DNA strand breaks. Additional assays such as homologous recombination reporters, DNA fiber analysis to monitor replication fork protection, and cell viability screens with DNA-damaging agents (e.g., PARP inhibitors) are well-suited. Flow cytometry can be used for cell cycle and apoptosis profiling. For further information or technical support, please contact Ascent Research.
