The DNAJB2 Knockout HGC-27 Polyclonal Cells represent a versatile loss-of-function model generated by CRISPR/Cas9-mediated gene disruption of DNAJB2 in the HGC-27 human gastric cancer cell line. This polyclonal knockout cell population enables the study of endogenous DNAJB2 function without monoclonal bias, providing a robust tool for investigating the co-chaperone??s role in protein quality control and stress signaling within a gastric carcinoma context.
HGC-27 is a human gastric adenocarcinoma epithelial cell line originally derived from a lymph node metastasis, widely employed to model gastric cancer biology, including tumor progression, metastasis, and therapeutic response. Its epithelial origin and tumorigenic properties make it suitable for dissecting pathways that govern cancer cell survival and proteotoxic stress adaptation.
DNAJB2 encodes a J-domain co-chaperone that is a critical partner of Hsp70 (HSPA1A/HSPA8), stimulating its ATPase activity to drive substrate binding to misfolded polypeptides. Through its recruitment of the E3 ubiquitin ligase STUB1 (CHIP), DNAJB2 facilitates ubiquitination of misfolded clients, directing them to the 26S proteasome for degradation. This functional interplay with BAG-family co-chaperones such as BAG1 and BAG3 positions DNAJB2 at a checkpoint of the Hsp70 chaperone cycle, linking protein refolding attempts with irreversible ubiquitin-proteasomal clearance. Under stress conditions, DNAJB2 expression is induced downstream of the transcription factor HSF1 and upstream stress signals including heat shock, oxidative stress, and hypoxia.
In gastric cancer cells, perturbation of the proteostasis network can profoundly influence tumor proliferation, apoptosis, and drug sensitivity. By disrupting DNAJB2 in HGC-27 cells, this model enables researchers to examine how loss of this Hsp70 co?chaperone impacts the handling of misfolded proteins, aggregate formation, and ubiquitin-dependent degradation. Given the elevated proteotoxic load in malignant cells, the polyclonal knockout population provides a physiologically relevant system to assess the dependence of gastric cancer cells on DNAJB2?mediated quality control and to explore potential synthetic lethal interactions with proteasome inhibitors.
Typical applications include functional characterization of DNAJB2 in chaperone?mediated degradation, assessment of proteasome activity and drug sensitivity assays with proteasome inhibitors, and analysis of protein aggregation through immunofluorescence. Co?immunoprecipitation and Western blotting can be used to map interacting partners such as Hsp70 and STUB1, while flow cytometry permits evaluation of apoptosis and stress responses. RT?qPCR and immunofluorescence extend the utility to quantifying pathway expression changes and cellular localization of aggregates. For further information or custom solutions, please contact Ascent Research.
