The ATP2C1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population in which the ATP2C1 gene has been disrupted, resulting in loss-of-function of the secretory pathway calcium ATPase 1 (SPCA1). This model provides a powerful tool for investigating Golgi Ca2+ homeostasis and Notch signaling in a near-haploid human cell background.
HAP1 cells are a near-haploid human cell line derived from the chronic myeloid leukemia cell line KBM-7, characterized by a haploid karyotype except for disomy of chromosome 8. This near-haploidy greatly facilitates single-allele knockout and loss-of-function screens, as only one allele typically needs to be targeted for complete gene disruption.
ATP2C1 encodes SPCA1, which transports Ca2+ and Mn2+ into the Golgi lumen, essential for protein folding, glycosylation, and processing. SPCA1 is regulated by p63 and interacts with calnexin and calreticulin. A key downstream effect is Notch receptor (NOTCH1-4) activation. In the Golgi, Ca2+-dependent furin cleaves Notch S1, enabling ligand-induced cleavage by gamma-secretase (PSEN1, PSEN2, NCSTN, APH1A) at S2/S3. This releases NICD, which translocates to the nucleus and converts RBPJ to an activator, inducing Notch targets. ATP2C1 disruption impairs Golgi Ca2+/Mn2+, inhibiting furin-mediated S1 cleavage and attenuating Notch signaling, compromising cell differentiation and adhesion.
Given that HAP1 cells originate from a chronic myeloid leukemia background, this knockout model permits the interrogation of Golgi-dependent signaling pathways in a hematological cancer context. The near-haploid nature of HAP1 cells ensures that CRISPR/Cas9-mediated disruption of the single ATP2C1 allele results in a uniform loss-of-function population, eliminating the complexity of heterozygosity and enabling robust phenotype-to-genotype correlations. This is particularly valuable for studying ATP2C1-related pathologies such as Hailey-Hailey disease, a skin blistering disorder caused by mutations in ATP2C1, as well as Notch-dependent cancers where SPCA1 function may influence tumor cell adhesion and differentiation.
This product is ideally suited for high-throughput genetic screens, quantitative RT-PCR and Western blotting to assess Notch target expression, immunofluorescence for Golgi analysis, and live-cell Ca2+ imaging. Additional characterization can include flow cytometry for surface proteins, adhesion assays, and drug sensitivity profiling. These polyclonal knockout cells are a versatile platform for functional genomics, drug target validation, and mechanistic studies of Golgi-dependent signaling. For more information, contact Ascent Research.
