DNAJC3 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the DNAJC3 gene in the HAP1 haploid human cell line. This heterogeneous pool enables loss-of-function studies of P58IPK, the encoded co-chaperone that acts as a negative regulator of PERK (EIF2AK3) signaling and the unfolded protein response (UPR). The polyclonal format supports robust population-level analyses without requiring clonal isolation, making it suitable for a range of functional genomics applications.
The HAP1 cell line is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia model. Its haploid karyotype ensures that a single genetic lesion produces a complete loss-of-function phenotype, eliminating the need for biallelic targeting. Widely used in functional genomics and drug discovery, HAP1 cells maintain functional ER stress and UPR pathways, providing a disease-relevant context for studying DNAJC3-mediated regulation of PERK.
DNAJC3 encodes P58IPK, a co-chaperone that directly binds and inhibits PERK kinase activity during ER stress, thereby attenuating phosphorylation of eIF2?? and promoting translational recovery. This regulation is part of a negative feedback loop, as DNAJC3 expression is induced by the transcription factors ATF4 and CHOP, which are themselves downstream of PERK. Key interacting partners include PERK, HSPA5 (BiP), and eIF2??. Disruption of DNAJC3 removes this inhibitory control, leading to sustained PERK activation, prolonged eIF2?? phosphorylation, global translational repression, and heightened susceptibility to ER stress-induced apoptosis.
In the haploid HAP1 background, the DNAJC3 knockout provides an unambiguous model for studying PERK pathway dynamics. Single-allele disruption eliminates confounding effects from a second allele, enabling precise quantification of signaling changes under ER stress inducers such as tunicamycin or thapsigargin. The chronic myeloid leukemia origin further allows exploration of cross-talk between ER stress responses and leukemogenic signaling, enhancing its utility for drug screening and disease modeling.
Typical research applications include immunoblotting for PERK and eIF2?? phosphorylation, RT-qPCR profiling of UPR target genes (e.g., ATF4, CHOP), cell viability and apoptosis assays under pharmacological ER stress, and ATF4 luciferase reporter assays. These cells are applied in UPR signaling analysis, PERK pathway dissection, integrated stress response studies, and disease modeling for inherited syndromic diabetes with neurodegeneration, type 2 diabetes, and neurodegenerative disorders. For further information, please contact Ascent Research.
