ASNS Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed for targeted disruption of the ASNS gene in the near-haploid human HAP1 cell line. This population-level knockout model lacks clonal selection and retains the polyclonal heterogeneity inherent to the parental HAP1 background, offering a versatile system for functional studies without the confounding effects of single-cell adaptation artifacts. The product is supplied as a mixed population of edited cells in which the ASNS locus has been disrupted by CRISPR/Cas9-mediated gene targeting, enabling loss-of-function investigations in a well-characterized genetic context.
The host HAP1 cell line is derived from the KBM-7 chronic myeloid leukemia line and is immortalized with a lymphoblastoid phenotype. It exhibits a near-haploid karyotype, retaining a single copy of each chromosome except for a portion of chromosome 15, which is disomic. This haploid nature simplifies genetic analysis, as recessive mutations can manifest directly without allelic compensation, making HAP1 cells a gold standard for functional genomic screens and knockout validation in cancer biology. The leukemic origin further contextualizes studies of amino acid metabolism and oncogenic signaling.
ASNS encodes asparagine synthetase, which catalyzes the ATP-dependent conversion of aspartate and glutamine to asparagine, requiring Mg2+ as a cofactor. Asparagine is a critical amino acid for protein and nucleotide biosynthesis, and ASNS expression is tightly regulated by the integrated stress response. Under amino acid deprivation, the GCN2 kinase phosphorylates eIF2??, leading to ATF4-mediated transcriptional upregulation of ASNS. mTORC1 signaling also modulates ASNS expression, and its activity feeds back to support mTORC1 activation through asparagine availability. Downstream, ASNS-driven asparagine production influences protein synthesis, autophagy, and nucleotide pools, interacting with transporters such as SLC1A3 and SLC38A2. The enzyme thus sits at a nexus connecting nutrient sensing (GCN2-eIF2??-ATF4 axis), mTORC1 signaling, and the unfolded protein response.
In the HAP1 background, ASNS knockout provides a powerful model to dissect amino acid homeostasis under stress conditions relevant to leukemia and solid tumors. Because HAP1 cells are leukemic and near-haploid, ASNS disruption unmasks dependencies on exogenous asparagine, facilitating studies of asparaginase sensitivity??a chemotherapeutic approach used in acute lymphoblastic leukemia. The model is particularly suitable for investigating resistance mechanisms to asparaginase, as well as crosstalk between ER stress, autophagy, and the mTORC1 pathway. The lack of a second allele eliminates masking effects, yielding unambiguous phenotypic readouts in viability and metabolic assays.
Typical research applications include CRISPR-based functional genomics, cancer metabolism profiling, drug screening for asparaginase sensitizers, and mechanistic studies of the integrated stress response. Viability assays under asparagine depletion or asparaginase treatment, coupled with ATF4 or phospho-eIF2?? immunoblotting and RT-qPCR for downstream targets, enable dissection of pathway engagement. Metabolomic analyses can reveal alterations in aspartate, glutamine, and nucleotide pools, while apoptosis assays quantify stress-induced cell death. This knockout model is also amenable to drop-out screens for synthetic lethal interactions. For further details or inquiries regarding the ASNS Knockout HAP1 Polyclonal Cells, please contact Ascent Research.
