The GXYLT1 Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 human near-haploid chronic myeloid leukemia cell line. This product is generated through CRISPR/Cas9-mediated disruption of the GXYLT1 gene, resulting in a heterogeneous pool of edited cells with loss-of-function mutations in the target gene. The polyclonal format provides a robust model for studying GXYLT1 deficiency without the clonal selection artifacts that can arise from single-cell-derived knockouts. This knockout cell population is suitable for functional genomics, signaling pathway analysis, and drug screening applications where a mixed genetic background better mimics biological variability.
The HAP1 cell line is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia line, with a male origin and adherent growth properties. Its near-haploid karyotype simplifies CRISPR-based knockout generation, as a single targeting event can produce complete gene disruption, making it an ideal platform for high-throughput functional genomics. HAP1 cells retain key signaling pathways relevant to cancer biology and cell adhesion, and they are widely used to study gene function in a range of biomedical contexts including cancer, immunology, and rare diseases.
GXYLT1 encodes a xylosyltransferase that catalyzes the transfer of xylose from UDP-xylose to specific serine residues in proteoglycan core proteins, initiating the assembly of glycosaminoglycan (GAG) chains such as heparan sulfate and chondroitin sulfate. This enzyme functions within the Golgi-resident glycosyltransferase complex alongside interacting partners B4GALT7 and B3GAT3, and acts upstream of elongation enzymes EXT1 and EXT2. Downstream targets include proteoglycans of the glypican and syndecan families, perlecan, and versican, which are critical modulators of growth factor signaling, cell adhesion, and extracellular matrix organization. GXYLT1-mediated xylosylation is a key regulatory step in GAG biosynthesis, influencing cellular responses to developmental cues and stress signals.
In the HAP1 cellular context, disruption of GXYLT1 disrupts the initiation of GAG chain biosynthesis on core proteins, leading to defective proteoglycan maturation. This model allows researchers to dissect the specific contribution of GXYLT1-dependent xylosylation to global glycosylation patterns and proteoglycan function. Because HAP1 cells express a range of proteoglycans, the knockout population serves as a valuable tool to investigate the molecular consequences of GXYLT1 loss on cell surface heparan sulfate and chondroitin sulfate expression, impacting pathways such as growth factor signaling and cell migration. The near-haploid background enhances the knockout efficiency, minimizing the presence of unedited cells and ensuring robust loss-of-function phenotypes across the population.
The GXYLT1 Knockout HAP1 Polyclonal Cells are suited for a broad array of research applications, including functional studies of glycosaminoglycan biosynthesis, disease modeling for spondyloepimetaphyseal dysplasia with joint dislocations (SEMD-JL) and congenital disorders of glycosylation, and investigation of proteoglycan-mediated signaling in cancer metastasis. Typical experimental approaches with this model include western blotting for glycosylated proteoglycans, lectin-based glycan analysis, flow cytometry for heparan sulfate expression, and metabolic labeling with radiolabeled xylose to assess GAG synthesis. Additionally, migration and invasion assays can be employed to evaluate the role of GXYLT1 in cancer cell motility, while RNA-seq enables transcriptome-wide assessment of glycosylation pathway alterations. For further details and technical support, please contact Ascent Research.
