HLCS Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population in the near-haploid human HAP1 cell line. These polyclonal knockout cells carry targeted disruptions in the HLCS gene, encoding holocarboxylase synthetase, via CRISPR/Cas9-mediated gene disruption. The polyclonal format provides a heterogeneous pool of edited alleles, enabling robust loss-of-function studies without the need for single-cell cloning. This model offers researchers a powerful tool for investigating HLCS-dependent processes in a human cellular context.
The parental HAP1 cell line is a human male near-haploid adherent cell line derived from the KBM-7 chronic myeloid leukemia (CML) cell line in blast crisis. Its near-haploid karyotype facilitates efficient knockout generation, as disruption of a single allele is sufficient to produce a null phenotype. HAP1 cells retain key signaling pathways and metabolic activities, making them suitable for functional genomics and drug discovery applications. The adherent growth and stable proliferation enable reproducible experimental manipulations.
HLCS catalyzes the ATP-dependent covalent attachment of biotin to specific lysine residues of apocarboxylases, including pyruvate carboxylase (PC), acetyl-CoA carboxylase (ACACA), propionyl-CoA carboxylase (PCC), and methylcrotonyl-CoA carboxylase (MCC), converting them into active holoenzymes essential for gluconeogenesis, fatty acid biosynthesis, and amino acid catabolism. Additionally, HLCS biotinylates histone H3 and histone H4, influencing chromatin structure and gene expression. Upstream regulators such as biotin availability and the sodium-dependent multivitamin transporter SLC5A6/SMVT control HLCS activity, while the SP1 transcription factor modulates HLCS gene expression. Downstream, these carboxylases function in critical metabolic pathways, and histone biotinylation marks impact transcriptional regulation. HLCS thus serves as a central node linking cellular biotin status to both metabolism and epigenetic regulation.
In the HAP1 near-haploid background, disruption of HLCS generates a clean loss-of-function model, facilitating dissection of biotin-dependent metabolic and epigenetic processes. The polyclonal knockout population preserves the genetic advantages of HAP1 cells while allowing assessment of population-level phenotypes. This system is particularly valuable for studying holocarboxylase synthetase deficiency and multiple carboxylase deficiency, as it recapitulates the enzymatic defect in a human cell line. The absence of a second functional allele simplifies interpretation of metabolic defects and gene expression changes, and the polyclonal nature reduces the risk of clonal artifacts.
HLCS Knockout HAP1 Polyclonal Cells are ideal for a range of biomedical investigations, including functional analysis of biotin metabolism, characterization of metabolic acidosis and organic acidurias, and dissection of histone biotinylation?mediated chromatin regulation. Experimental approaches such as western blotting for HLCS protein, RT?qPCR for mRNA expression, biotinylation assays of carboxylases, enzymatic activity measurements of pyruvate carboxylase, and chromatin immunoprecipitation for histone biotinylation are readily applicable. Drug screening for biotin?responsive disorders and metabolic profiling by mass spectrometry can be performed using this cellular model. Additionally, cell proliferation assays in biotin?depleted medium allow assessment of biotin auxotrophy. For further details or to request a custom cell engineering project, please contact Ascent Research.
