The DNAJC1 Knockout HEK293T Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout population targeting the DNAJC1 gene in human HEK293T cells. This product provides a heterogeneous pool of cells with gene disruption, enabling loss-of-function studies of the ER co-chaperone DNAJC1 (DnaJ heat shock protein family (Hsp40) member C1, also known as ERj1). The polyclonal format captures the natural diversity of editing outcomes, making it suitable for experiments where clonal homogeneity is not required, such as population-based phenotypic assays, biochemical analyses, and signaling studies. It serves as a versatile tool for investigating the roles of DNAJC1 in protein homeostasis and the unfolded protein response (UPR).
The host cell line, HEK293T, is a widely used derivative of human embryonic kidney 293 cells that expresses the SV40 large T antigen. These adherent epithelial cells are renowned for high transfectability and robust protein expression, making them a mainstay for recombinant protein production, viral packaging, and transient expression studies. The HEK293T background offers a permissive environment for examining secretory pathway functions and ER stress responses due to its active protein synthesis and secretion machinery. This model system is particularly well-suited for studying the chaperone networks that govern protein translocation and quality control in the endoplasmic reticulum.
DNAJC1 encodes an ER-resident co-chaperone that recruits Hsp70 family chaperones, primarily BiP (GRP78), to the Sec61 translocon complex, facilitating co-translational import of nascent polypeptides into the ER lumen. DNAJC1 also participates in post-translocational folding and ER-associated degradation (ERAD) of misfolded proteins. Under ER stress conditions induced by agents like tunicamycin or thapsigargin, upstream regulators such as XBP1, ATF6, and ATF4 orchestrate UPR signaling, where DNAJC1 modulates BiP availability and influences the balance between folding capacity and stress responses. Interacting factors include calnexin, calreticulin, and other ERdj proteins, while downstream effects impinge on the fate of secretory and membrane proteins. Pathway crosstalk involves key UPR sensors IRE1?? and PERK, the transcription factor CHOP, and the ERAD machinery components p97/VCP and HRD1.
In the HEK293T context, disruption of DNAJC1 provides a physiologically relevant model to dissect ER chaperone dynamics. HEK293T cells constitutively support high levels of protein synthesis and secretion, making them sensitive to perturbations in ER homeostasis. Knockout of this co-chaperone can unmask compensatory mechanisms within the ER chaperone network and reveal DNAJC1-dependent substrates. The polyclonal nature of the knockout population simulates a mixed genetic background, which may better reflect tissue-level heterogeneity and is advantageous for studying threshold effects in UPR activation or for screening chemical modulators where subtle phenotypic variations are informative. This system allows for the evaluation of how loss of DNAJC1 impacts BiP recruitment, ERAD efficiency, and the cellular response to proteotoxic stress.
Researchers can employ these polyclonal knockout cells in a variety of experimental settings. Typical assays include Western blotting to monitor UPR markers such as BiP and CHOP, RT-qPCR for quantifying XBP1 splicing or ATF4/CHOP transcript levels, and co-immunoprecipitation to assess Hsp70 interactions. Immunofluorescence microscopy can localize ER stress markers, while luciferase-based reporters provide quantitative readouts of UPR pathway activation. Flow cytometry enables apoptosis analysis under chronic ER stress. These cells are ideal for studies in cancer biology, neurodegeneration, and protein misfolding disorders, as well as for chaperone-targeted drug discovery. For additional information or technical support, please contact Ascent Research.
