The DNAJB1 Knockout HeLa Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population, in which the DNAJB1 gene is disrupted across a pool of HeLa cells. This heterogeneous population avoids the clonal selection inherent in monoclonal lines, reducing clone-specific artifacts and providing a more representative loss-of-function model. The product is generated by delivering Cas9 and guide RNAs targeting DNAJB1, resulting in a mixed allelic series that collectively reduces DNAJB1 protein expression. These cells serve as a versatile tool for studying DNAJB1-dependent processes in cellular proteostasis.
The parental HeLa cell line originates from a cervical adenocarcinoma and is among the most widely used human cancer cell models. HeLa cells are HPV18-positive, expressing the viral oncoproteins E6 and E7, which inactivate the tumor suppressors p53 and Rb, respectively. This immortalized, adherent epithelial line offers reliable growth characteristics and is a staple in cell and molecular biology research. Its genetic background makes it particularly suited for investigating stress responses and chaperone networks, as the viral oncoproteins already impinge on cell cycle and apoptosis checkpoints.
DNAJB1 is a member of the J-domain protein family and functions as a co-chaperone for Hsp70. It directly interacts with Hsp70 and stimulates its ATPase activity, accelerating the chaperone cycle and facilitating substrate binding and release. DNAJB1 recruits misfolded client proteins to Hsp70 for productive folding or, in cooperation with the ubiquitin ligase CHIP and nucleotide exchange factors such as BAG1, directs them to the proteasome for degradation. Its expression is regulated by the transcription factor HSF1 in response to heat shock, oxidative stress, and unfolded protein stress, and it influences the fate of downstream targets including aggregated proteins.
In the HeLa context, knockout of DNAJB1 impairs chaperone-mediated proteostasis, leading to accumulation of misfolded and aggregated proteins and altered cellular stress responses. Given HeLa cells?? HPV-driven inactivation of p53 and Rb, they exhibit altered apoptotic and senescence pathways, making them an excellent platform to study how cancer cells rely on chaperones for survival under proteotoxic stress. This model is highly relevant to cancer biology, protein misfolding diseases, and neurodegeneration research, where proteostasis imbalance is a hallmark.
Researchers can utilize these polyclonal knockout cells in a variety of assays to investigate proteostasis and chaperone biology. Western blotting for DNAJB1 and Hsp70 confirms protein-level knockdown, while immunofluorescence reveals intracellular protein aggregates. Proteasome activity assays and RT-qPCR for HSF1-target genes monitor stress responses. Cell viability experiments under heat shock or oxidative stress, along with co-immunoprecipitation of Hsp70 complexes, enable dissection of chaperone interactions. The polyclonal pool format supports high-throughput screening. Contact Ascent Research for details.
