The DNAJB11 Knockout HeLa Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the DNAJB11 gene, which encodes an essential ER-resident co-chaperone. By employing a heterogeneous pool of edited cells, this product avoids the clonal artifacts inherent in monoclonal knockouts and provides a biologically averaged loss-of-function model suitable for studying gene function in signaling networks where cellular heterogeneity may influence outcomes. This format is particularly useful for investigating endoplasmic reticulum (ER) protein homeostasis and stress responses in a robust experimental system.
The HeLa host cell line is an immortalized human cervical adenocarcinoma cell line derived from an epithelial tumor and stably harbors integrated human papillomavirus type 18 (HPV18) DNA. HeLa cells are among the most widely used models in biomedical research due to their rapid proliferation, ease of genetic manipulation, and well-characterized signaling pathways. Their consistent growth properties and genetic stability make them an ideal platform for CRISPR-based functional genomics studies, ensuring reproducibility across experiments.
DNAJB11, also termed ERdj3, is a type I ER membrane co-chaperone that directly stimulates the ATPase activity of BiP (HSPA5/GRP78), a central Hsp70 chaperone. Through ATP hydrolysis, DNAJB11 promotes BiP binding to unfolded client proteins, facilitating their folding or targeting them to ER-associated degradation (ERAD). DNAJB11 physically interacts with BiP, HSPA8, and the VCP/p97 retrotranslocation complex. Its expression is upregulated by the UPR transcription factors XBP1s and ATF6 under ER stress. Functionally, DNAJB11 acts upstream of CHOP (DDIT3) to suppress ER stress-induced apoptosis. Consequently, knockout of DNAJB11 disrupts this cytoprotective role, leading to activation of the IRE1?? (ERN1)?CXBP1s, PERK (EIF2AK3)?CeIF2??, and ATF6 signaling branches, and sensitizes cells to ER stress agents such as tunicamycin.
In the HeLa carcinoma background, loss of DNAJB11 imposes a significant burden on the protein quality control machinery, revealing the dependency of cancer cells on efficient ER proteostasis. This model enables detailed dissection of how ER co-chaperone dysfunction contributes to pathologies such as autosomal dominant polycystic kidney disease (ADPKD) and hepatic fibrosis, as well as cancer cell adaptation to stress. Studying DNAJB11 knockout in this context illuminates the crosstalk between UPR signaling and ERAD in determining cell fate decisions.
Research applications include quantitative UPR pathway analysis via western blotting for BiP, CHOP, and phospho-eIF2??; RT-qPCR for XBP1 splicing; immunofluorescence for BiP and ER markers; apoptosis assays monitoring cleaved caspase-3; and cell viability under tunicamycin treatment. Co-immunoprecipitation of BiP interactors and ERSE luciferase reporter assays provide mechanistic insight into chaperone networks and transcriptional UPR output. This product is suited for high-throughput screening of ER stress modulators, mechanistic studies of protein folding, and disease modeling for ADPKD and cancer-related stress responses. For further information, contact Ascent Research.
