The DUSP8 Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population in which the DUSP8 gene has been disrupted to generate a loss-of-function model. This product consists of a heterogeneous pool of HAP1 cells carrying diverse editing events at the DUSP8 locus, providing a versatile tool for studying gene function without clonal selection. The polyclonal format is particularly suited for pooled phenotypic screens and bulk biochemical analyses where population-level responses are relevant. Researchers can pair this knockout model with wild-type HAP1 controls to dissect the specific contribution of DUSP8 to cellular signaling networks.
The HAP1 host cell line is a human near-haploid myeloid leukemia cell line derived from the KBM-7 chronic myeloid leukemia lineage. Its near-haploid karyotype, with a single copy of most chromosomes except for a disomic region on chromosome 8, simplifies gene targeting and reduces the complexity of knockout generation. HAP1 cells retain key features of myeloid cells and are widely used for haploid genetic screens, CRISPR-based functional genomics, and biochemical pathway analysis. Their adherent growth and rapid proliferation facilitate high-throughput assays, making them a practical platform for studying genes involved in signaling and disease mechanisms.
DUSP8 encodes a dual-specificity phosphatase that specifically dephosphorylates phospho-tyrosine and phospho-threonine residues on JNK and p38 MAP kinases, thereby negatively regulating MAPK signaling. DUSP8 is activated by upstream stress signals through JNK and p38 and functions downstream of components such as ASK1, MKK4/MKK7, and MKK3/MKK6. By dephosphorylating JNK1, JNK2, and p38 MAPK, DUSP8 attenuates the phosphorylation of downstream transcription factors including c-Jun, ATF2, and MAPKAPK2, ultimately modulating gene expression programs driven by AP-1 and NF-??B. This phosphatase acts as a critical negative feedback regulator in apoptosis, stress responses, and immune signaling, with implications in autoimmune diseases and cancer.
The HAP1 background offers unique advantages for dissecting DUSP8 function. Because p38 and JNK pathways influence apoptosis, cytokine production, and cell cycle control in myeloid cells, knockout of DUSP8 in this leukemic context allows investigation of how dysregulated MAPK phosphatase activity contributes to abnormal survival or inflammatory phenotypes. The near-haploid state reduces allele compensation effects, enabling cleaner interpretation of gene disruption impacts. These cells are therefore well-suited for studying the role of DUSP8 in stress-induced apoptosis, inflammatory mediator release, and kinase network rewiring, particularly in disease models of systemic lupus erythematosus and rheumatoid arthritis.
Typical applications include functional characterization of DUSP8 in MAPK signaling using phospho-specific western blotting for phospho-JNK and phospho-p38, RT-qPCR for downstream targets, and flow cytometry-based apoptosis assays. The knockout population supports drug screening for JNK/p38 pathway modulators via phospho-kinase arrays, reporter assays for AP-1/NF-??B activity, and cytokine profiling. Immunoprecipitation studies can assess DUSP8 substrate interactions, while cell viability and drug sensitivity assays explore therapeutic vulnerabilities in the absence of DUSP8. For technical inquiries, please contact Ascent Research.
