The BLM Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 human cell line, featuring targeted disruption of the BLM gene. This product provides a heterogeneous pool of loss-of-function cells, generated without single-cell cloning, enabling the study of BLM-dependent pathways in a genetically tractable background. The polyclonal format offers a robust model for functional assays while mitigating clonal artifacts, making it suitable for high-throughput screening and mechanistic investigations.
HAP1 is a near-haploid human cell line originally derived from the KBM-7 chronic myeloid leukemia (CML) line, characterized by a male karyotype and a single copy of most chromosomes. Its haploid nature simplifies CRISPR/Cas9-mediated gene targeting, as a single allelic disruption often yields a complete knockout phenotype. Widely used in functional genomics, HAP1 cells combine ease of genetic manipulation with relevance to hematological malignancy research, providing a consistent platform for studying DNA repair, cell cycle control, and drug responses.
BLM encodes a RecQ DNA helicase critical for genomic stability by resolving DNA recombination intermediates, including Holliday junctions and D-loops, through the BLM?CTOP3A?CRMI1?CRMI2 complex. This process suppresses sister chromatid exchanges (SCEs) and is activated by ATM/ATR-mediated phosphorylation in response to replication stress and DNA damage. The helicase also interacts with RAD51, BRCA1, FANCD2, and MLH1, linking BLM to homologous recombination repair and the Fanconi anemia pathway. Upstream regulators p53 and CDK2/cyclin E further modulate BLM expression and function, ensuring coordinated responses to genomic instability.
In the near-haploid HAP1 context, BLM knockout yields a clear loss-of-function phenotype, characterized by elevated sister chromatid exchanges, defective replication stress resolution, and heightened sensitivity to DNA-damaging agents. This model is particularly valuable for investigating Bloom syndrome pathophysiology, cancer predisposition, and the role of genomic instability in leukemia and lymphoma, leveraging the hematopoietic origin of the HAP1 line.
These polyclonal knockout cells are suitable for a variety of assays, including sister chromatid exchange (SCE) analysis, clonogenic survival assays with genotoxic drugs (e.g., mitomycin C, hydroxyurea), comet assays, and homologous recombination reporter systems. They also support flow cytometry for cell cycle profiling and apoptosis, as well as functional genomics screens for synthetic lethal interactions. Validation by Western blotting, RT-qPCR, and immunofluorescence ensures reliable pathway assessment. For further information, contact Ascent Research.
