The EDEM3 Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the Raji B lymphocyte line, designed to disrupt the EDEM3 gene. This polyclonal pool provides a heterogeneous loss-of-function model for investigating ER-associated degradation (ERAD) and the unfolded protein response (UPR). Using CRISPR/Cas9-mediated gene disruption, the cells lack functional EDEM3, enabling studies of its role in glycoprotein quality control within the endoplasmic reticulum.
The Raji host cell line is an EBV-positive Burkitt lymphoma-derived B lymphocyte line, widely utilized in research on B-cell malignancies, Epstein?CBarr virus biology, and humoral immunity. Raji cells exhibit robust secretory pathway activity, making them a valuable system for exploring how ER stress and protein misfolding intersect with lymphomagenesis. Their EBV status further permits investigations into viral manipulation of host cell proteostasis and ERAD pathways.
EDEM3 encodes a mannosidase that accelerates clearance of terminally misfolded N-glycoproteins from the ER lumen. It acts upstream of the HRD1?CSEL1L retrotranslocation complex, interacting with OS9, XTP3-B, and ERLEC1 to trim mannose residues, thereby targeting substrates for VCP/p97-mediated extraction and ubiquitin?Cproteasome degradation. EDEM3 expression is induced by ER stress through the IRE1?CXBP1 and ATF6 branches of the UPR, and its activity suppresses apoptosis by reducing ER burden. Downstream effects include diminished proteasomal load upon resolution of stress.
In B lymphocytes, high immunoglobulin synthesis imposes a heavy folding demand on the ER; consequently, the ERAD pathway and EDEM3 are critical for maintaining proteostasis and preventing apoptosis under stress conditions. EBV, which infects Raji cells, is known to modulate ER stress and UPR signaling to favor viral persistence and oncogenesis. Thus, EDEM3 disruption in this model provides a physiologically relevant platform to dissect how ERAD dysfunction contributes to B-cell lymphoma biology, chemo-resistance, and ER stress vulnerability.
This knockout polyclonal population is suited for drug sensitivity profiling, for instance assessing responses to proteasome inhibitors (e.g., bortezomib), ER stress inducers (tunicamycin, thapsigargin), or UPR modulators. Representative assays include immunoblotting for EDEM3 and UPR markers (BIP, CHOP), RT-qPCR analysis of XBP1 splicing and ATF4 targets, flow cytometry with ER stress reporters, and co?immunoprecipitation of EDEM3?interacting proteins (HRD1, OS9, VCP). Apoptosis and proteasome activity measurements can further clarify the functional consequences of EDEM3 loss in the context of EBV?positive lymphoma. For additional technical specifications or to discuss custom gene-edited cell models, please contact Ascent Research.
