The DNAJB9 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population derived from the SK-HEP-1 human liver adenocarcinoma cell line, with targeted disruption of the DNAJB9 gene. This product offers a heterogeneous loss-of-function model to study ER proteostasis and the unfolded protein response (UPR). The polyclonal format captures a range of knockout efficiencies, enabling population-based analyses of ER stress signaling without requiring single-cell clonal selection.
The SK-HEP-1 cell line originates from ascites of a hepatocellular carcinoma patient and exhibits both epithelial and mesenchymal characteristics. It is extensively used in liver cancer research and endothelial biology studies, providing a robust platform to interrogate tumor cell adaptation to microenvironmental stresses, including ER stress. This line??s dual phenotype makes it valuable for investigating how ER protein homeostasis intersects with metastatic potential.
DNAJB9 is an ER-localized co-chaperone that partners with HSPA5 (BiP) to assist protein folding and target misfolded proteins for ER-associated degradation (ERAD). Under ER stress, DNAJB9 is transcriptionally upregulated by ATF6 and XBP1. It functionally interacts with the IRE1??-XBP1 axis and cooperates with VCP/p97 and other ERAD components to maintain proteostasis. Knockout of DNAJB9 disrupts these processes, leading to accumulation of misfolded proteins and altered UPR signaling through PERK, IRE1??, and ATF6 branches, which can modulate cell survival and apoptosis.
In the SK-HEP-1 context, loss of DNAJB9 exacerbates ER stress, providing a model to decipher how proteotoxic burden influences hepatocellular carcinoma cell fitness. Elevated basal ER stress is common in liver tumors due to metabolic and hypoxic pressures; thus, DNAJB9 knockout cells enable investigation of vulnerabilities arising from impaired ERAD. This system also permits exploration of the relationship between epithelial-mesenchymal transition and UPR regulation, relevant for understanding tumor progression and drug resistance.
Typical applications include western blotting for ER stress markers (e.g., BiP, CHOP), RT-qPCR analysis of UPR gene expression, flow cytometry for apoptosis, and immunofluorescence to visualize ER morphology. The polyclonal knockout pool is suited for mechanistic studies of ERAD, screening of ER stress modulators, and modeling protein misfolding disorders in a hepatic environment. For more information, please contact Ascent Research.
