BTD Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from HAP1, a near-haploid human chronic myeloid leukemia cell line, with disruption of the BTD gene to eliminate biotinidase function. This polyclonal format provides a heterogeneous pool of edited cells, enabling robust loss-of-function analyses without clonal selection. Supplied as a ready-to-use population, it is suitable for expansion and downstream metabolic and functional assays.
HAP1 originates from KBM-7 chronic myeloid leukemia cells and retains a near-haploid karyotype, BCR-ABL1 expression, and p53 deficiency. Its haploid genetic background simplifies genome editing and facilitates clear genotype?Cphenotype correlations, making it a favored host for CRISPR screens. HAP1 cells maintain leukemia-relevant signaling while remaining easy to culture, and are widely used in functional genomics and drug sensitivity studies.
BTD encodes biotinidase, which recycles biotin by hydrolyzing biocytin and biotinyl-peptides, providing free biotin for holocarboxylase synthesis by HLCS. Loss of BTD disrupts biotin salvage, impairing the activities of acetyl-CoA carboxylase (ACC1/ACC2), pyruvate carboxylase, propionyl-CoA carboxylase, and 3-methylcrotonyl-CoA carboxylase. BTD expression is regulated by HNF4A, SP1, and SMAD3, and its deficiency leads to multiple carboxylase deficiency, impacting fatty acid synthesis, gluconeogenesis, and amino acid catabolism.
In the HAP1 background, BTD knockout models biotinidase deficiency, characterized by biotin depletion and carboxylase dysfunction. The combination of near-haploidy, BCR-ABL1 oncogenic signaling, and p53 loss offers a unique system to study metabolic vulnerabilities and biotin dependency in leukemia. This model can be used to explore how biotin restriction sensitizes cancer cells and to dissect the interplay between oncogenic pathways and vitamin metabolism.
Research applications include studying biotin metabolism, mapping carboxylase-dependent pathways, and testing drug responses under biotin-limited conditions. Typical assays involve RT-qPCR and western blot for BTD expression, biotinidase activity assays, biotin quantification, cell viability under biotin depletion, propionyl-CoA carboxylase activity, and metabolic profiling by mass spectrometry. This polyclonal model supports CRISPR phenotypic screening and metabolic investigations in a CML-relevant context. For further details, please contact Ascent Research.
