The DPYD Knockout HAP1 Polyclonal Cells product provides a CRISPR/Cas9-edited polyclonal knockout cell population engineered to disrupt the DPYD gene in the human near-haploid HAP1 cell line. This loss-of-function model enables investigation of dihydropyrimidine dehydrogenase (DPD) function and its role in pyrimidine metabolism, without imposing any specific clonal or editing-pattern characteristics. The polyclonal format captures a heterogeneous knockout population, reflecting varied editing outcomes while maintaining robust target-gene disruption.
HAP1 cells are a chronic myeloid leukemia-derived near-haploid cell line originally established from KBM-7 cells. The near-haploid karyotype facilitates high-efficiency gene targeting and phenotypic characterization, making HAP1 a well-established host for CRISPR-based functional genomics studies. Its leukemia background further provides a unique context for exploring metabolic and chemosensitivity phenotypes, particularly those relevant to targeted therapeutics and drug metabolism.
DPYD encodes dihydropyrimidine dehydrogenase, the rate-limiting enzyme in pyrimidine catabolism that reduces uracil and thymine to their dihydro forms, utilizing the cofactors NADPH and FAD. DPYD also inactivates the fluoropyrimidine chemotherapeutic 5-fluorouracil. Transcriptional regulation involves upstream regulators such as NF-??B, p53, and the microRNAs miR-27a and miR-27b. DPYD acts upstream of dihydrouracil and dihydrothymine production, directly interacting with NADPH, FAD, and 5-fluorouracil. Disruption of DPYD therefore impairs pyrimidine degradation and alters the metabolic fate of uracil, thymine, and fluoropyrimidines.
In the HAP1 cell model, DPYD knockout abolishes dihydropyrimidine dehydrogenase activity, disrupting the pyrimidine catabolic pathway and modifying cellular sensitivity to fluoropyrimidine drugs such as 5-fluorouracil. This model recapitulates aspects of dihydropyrimidine dehydrogenase deficiency, a pharmacogenetic condition linked to severe fluoropyrimidine toxicity. It also serves as a platform to investigate pyrimidine metabolism in cancer biology, particularly in the context of colorectal and breast cancers where fluoropyrimidine therapy is central.
Researchers can employ these polyclonal knockout cells in a range of assays, including fluoropyrimidine cytotoxicity assays to assess drug sensitivity, DPYD enzyme activity measurements to confirm functional knockout, pyrimidine metabolite profiling by LC-MS to monitor uracil, thymine, and dihydropyrimidine levels, and gene expression analysis via RT-qPCR or Western blotting. The model supports applications in fluoropyrimidine toxicity studies, pyrimidine metabolism research, drug sensitivity screening, and DPYD gene function analysis, offering a versatile tool for academic and pharmaceutical investigation. For further information or custom requests, please contact Ascent Research.
