The DNAJC1 knockout Huh-7 polyclonal cells constitute a CRISPR/Cas9-edited polyclonal knockout cell population, derived from the human Huh-7 hepatocellular carcinoma cell line, designed for loss-of-function interrogation of the DNAJC1 gene. DNAJC1 encodes an Hsp40 co-chaperone that modulates Hsp70 chaperone activity, playing critical roles in protein folding, endoplasmic reticulum (ER)-associated degradation, and the unfolded protein response (UPR). This polyclonal knockout model provides a physiologically relevant system to dissect DNAJC1 function without the limitations of clonal variation, enabling robust assessment of target-gene disruption effects across a heterogeneous cell population.
Huh-7 cells, established from the hepatocellular carcinoma of a 57-year-old Japanese male, exhibit an adherent epithelial morphology and are widely employed as a model for liver cancer biology and hepatitis C virus (HCV) replication. The cell line retains key hepatic features and supports the complete viral life cycle, making it an indispensable tool for studying host?Cpathogen interactions and oncogenic signaling. The knockout of DNAJC1 in this background offers a unique platform to investigate how co-chaperone networks influence malignant phenotypes and viral propagation in a disease-relevant context.
At the molecular level, DNAJC1 functions as a co-chaperone that binds Hsp70 family members, including HSPA1A and HSPA5/BiP, to facilitate substrate recognition, folding, and targeting to the ERAD machinery (HRD1, SEL1L). DNAJC1 is regulated by ER stress inducers such as tunicamycin and thapsigargin, heat shock, and viral proteins including the HCV core and NS5A, with upstream control mediated by transcription factors ATF6 and XBP1. Downstream, DNAJC1 influences the expression and activity of UPR effectors CHOP and ATF4, and it physically interacts with the Sec61 translocon and other DNAJ co-chaperones, positioning it at the intersection of proteostasis and viral replication. DNAJC1 disruption therefore perturbs the Hsp70 chaperone cycle, potentially impairing ER stress resilience and altering the cellular environment required for HCV replication.
In Huh-7 cells, DNAJC1 knockout is expected to compromise the ER stress response, leading to altered UPR signaling and increased susceptibility to proteotoxic damage, which is particularly relevant for hepatocellular carcinoma cells that rely on enhanced chaperone capacity to survive chronic stress. Additionally, because DNAJC1 interacts with HCV NS5A, its loss may attenuate viral replication by destabilizing the membrane-associated replication complex. This polyclonal knockout population thus serves as a powerful tool for dissecting the dual role of DNAJC1 in liver cancer progression and viral pathogenesis, offering insights into how chaperone networks maintain cellular homeostasis and support pathogen exploitation.
Typical research applications encompass mechanistic studies of ER stress response pathways in liver cancer, where knockout cells can be challenged with tunicamycin and analyzed via western blotting for UPR markers such as BiP and CHOP, or RT-qPCR for ATF4 and XBP1 splicing. Functional assays include co-immunoprecipitation to assess disrupted Hsp70?Csubstrate interactions, immunofluorescence for protein localization, and HCV replicon or infection assays to measure viral replication efficiency. The model is also suited for drug screening campaigns targeting proteostasis modulators, using cell viability and apoptosis assays (annexin V flow cytometry) under ER stress. These applications make the DNAJC1 knockout Huh-7 polyclonal cells an essential resource for researchers investigating chaperone biology, liver cancer, and viral?Chost interactions. For further information, please contact Ascent Research.
