DNAJB2 Knockout Raji Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the Raji B lymphoblastoid cell line, engineered to disrupt the DNAJB2 gene. This product provides a loss-of-function model for investigating the cellular roles of DNAJB2, a DnaJ/Hsp40 family co-chaperone essential for protein quality control. The polyclonal nature of the knockout population allows study of heterogeneous gene disruption effects, avoiding clonal selection biases. Researchers can employ these cells to examine DNAJB2-dependent mechanisms in a human Burkitt’s lymphoma-derived B lymphocyte background, with applications spanning chaperone biology, proteostasis, and stress response pathways.
The Raji host cell line originates from a Burkitt’s lymphoma patient and exhibits a B lymphoblast phenotype, characterized by robust proliferation and expression of B cell markers. These cells are widely used in immunology and cancer research due to their competent protein synthesis and secretion machinery, which imposes high demands on protein folding and degradation pathways. The B lymphocyte context is particularly relevant for dissecting how DNAJB2 maintains proteostasis under conditions of elevated immunoglobulin production and secretory stress, making this knockout model suitable for studying chaperone-mediated quality control in immune cells.
DNAJB2 functions as a co-chaperone that recruits Hsp70 to misfolded substrates, facilitating either refolding or targeting to the ubiquitin-proteasome system. It interacts directly with Hsp70/Hsc70 and the STUB1/CHIP ubiquitin ligase to promote degradation of ubiquitinated proteins. DNAJB2 transcription is activated by HSF1 in response to heat shock, proteotoxic stress, and the unfolded protein response, positioning it within a network that includes chaperone-mediated autophagy and ER-associated degradation components. Loss of DNAJB2 disrupts the Hsp70 chaperone cycle, impairing removal of aggregation-prone proteins and compromising cellular protein homeostasis.
In Raji cells, DNAJB2 knockout is predicted to sensitize the cells to proteotoxic insults, leading to accumulation of ubiquitinated aggregates and reduced viability under stress conditions. Although DNAJB2 mutations are primarily linked to distal hereditary motor neuronopathy and Charcot-Marie-Tooth disease type 2, its fundamental role in protein quality control makes this knockout model valuable for studying common mechanisms of neurodegeneration and for screening compounds that modulate proteostasis. The B lymphoblast background enables interrogation of cell-type-specific vulnerabilities in chaperone networks, potentially uncovering general principles of protein aggregation toxicity.
Key research applications include mechanistic studies of Hsp70 co-chaperone function, protein aggregation assays, and drug screening for modulators of the heat shock response. Representative experimental workflows involve Western blotting for ubiquitinated proteins, immunofluorescence detection of aggresomes, co-immunoprecipitation of Hsp70 complexes, proteasome activity measurements, and autophagy flux analyses. Additionally, cell viability assays under endoplasmic reticulum or oxidative stress can link DNAJB2 loss to functional outcomes. For further information or custom inquiries, please contact Ascent Research.
