The DUSP18 Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed for functional studies of dual-specificity phosphatase 18 (DUSP18) in a near-haploid human cell background. This polyclonal knockout product provides a heterogeneous pool of gene-disrupted cells, enabling robust loss-of-function analyses without clonal selection biases. The CRISPR/Cas9-mediated gene disruption targets DUSP18 to eliminate its expression, allowing researchers to interrogate its regulatory roles in stress-responsive kinase signaling.
HAP1 cells are derived from the KBM-7 chronic myeloid leukemia cell line and possess a near-haploid karyotype, which simplifies genetic manipulation and facilitates efficient knockout generation. This near-haploid nature reduces the likelihood of non-disrupted alleles, enhancing the model’s utility for genetic interaction screens and systematic pathway analyses. HAP1 cells exhibit fibroblast-like morphology and share signaling pathways common to many cell types, making them a versatile platform for studying conserved cellular processes such as apoptosis, proliferation, and stress responses.
DUSP18 is a dual-specificity phosphatase that selectively dephosphorylates and inactivates the stress-activated mitogen-activated protein kinases (MAPKs) JNK1/2/3 and p38??/??. By removing phosphate groups from the TXY activation motif, DUSP18 negatively regulates these kinases downstream of upstream activators like MEKK1, ASK1, MKK4, and MKK7. Consequently, DUSP18 attenuates signaling cascades that lead to phosphorylation of transcription factors c-Jun and ATF2, as well as the activation of the AP-1 complex. This phosphatase is induced by oxidative stress and inflammatory cytokines such as TNF-?? and IL-1??, thereby serving as a feedback brake on JNK and p38 pathways.
In HAP1 cells, disruption of DUSP18 creates a sensitized background for studying prolonged or amplified MAPK signaling. Without DUSP18-mediated damping, the phosphorylation and activity of JNK and p38 are likely sustained, leading to enhanced transcription of stress-responsive genes. This model allows dissection of the specific contributions of DUSP18 to cell survival, apoptosis, and inflammatory responses in a controlled genetic environment. The near-haploid nature of HAP1 cells ensures that the knockout effect is not masked by a second functional allele, providing a cleaner assessment of phenotype.
The DUSP18 Knockout HAP1 Polyclonal Cells are suited for a variety of functional assays, including Western blotting for phospho-JNK and phospho-p38 to monitor MAPK activation status, RT-qPCR for downstream target gene expression, and JNK kinase activity assays. They can also be used in apoptosis assays (e.g., Annexin V staining), cell viability measurements under stress conditions, immunofluorescence to track phospho-JNK localization, and AP-1 luciferase reporter assays to gauge transcription factor activity. Additionally, these cells are ideal for RNA-seq profiling to map global gene expression changes associated with DUSP18 loss, and for drug screening aimed at modulating MAPK-driven pathologies such as cancer and inflammation. For more information about this knockout model, please contact Ascent Research.
