The CRBN Knockout Raji Polyclonal Cells consist of a polyclonal population of human Raji B lymphoblastoid cells in which the CRBN gene has been disrupted by CRISPR/Cas9-mediated genome editing, generating a heterogeneous loss-of-function model for cereblon. This polyclonal knockout cell pool retains diverse genetic backgrounds while uniformly lacking functional CRBN expression, enabling robust studies of cereblon-dependent processes without clonal artifacts.
Raji cells are a well-established B lymphocyte line derived from a Burkitt lymphoma patient. They serve as a versatile model for B-cell biology, including apoptosis, lymphomagenesis, and humoral immunity, and their rapid growth and genetic tractability facilitate detailed mechanistic investigations of ubiquitin ligase function in a lymphoid context.
CRBN encodes the substrate receptor of the CUL4?CDDB1?CRBX1 E3 ubiquitin ligase complex, which targets specific proteins for ubiquitination and proteasomal degradation. CRBN activity is influenced by upstream factors such as interferon gamma and SP1, and is pharmacologically redirected by immunomodulatory imide drugs (IMiDs) including thalidomide, lenalidomide, and pomalidomide. Upon IMiD binding, CRBN acquires neosubstrates, notably the transcription factors IKZF1 (Ikaros) and IKZF3 (Aiolos), as well as the kinase CK1?? (CSNK1A1) and translation terminator GSPT1. CRBN directly interacts with DDB1, CUL4A/B, and RBX1 to assemble the active ligase, and HSP90 associates with the complex. Disruption of CRBN therefore prevents ubiquitin-mediated turnover of these clients, altering downstream signaling critical for lymphocyte proliferation and survival.
In Raji B cells, CRBN knockout provides a clinically relevant model to dissect IMiD mechanism of action and resistance. Since IMiDs depend on CRBN to drive degradation of IKZF1 and IKZF3??events that are cytotoxic in B-cell neoplasms??loss of CRBN confers resistance, mirroring a resistant phenotype observed in myeloma and lymphoma patients. Moreover, this model enables exploration of cereblon??s endogenous role in protein homeostasis and apoptosis regulation in lymphoma without pharmacological interference.
Typical applications include Western blotting for CRBN and substrate proteins, ubiquitination assays, and co-immunoprecipitation to assess ligase complex integrity. Cell viability and apoptosis assays with IMiDs can quantify drug response, while transcriptomic and proteomic analyses reveal global effects of CRBN loss. The polyclonal cells are also suitable for CRISPR-based synthetic lethality screens and studies of drug-induced protein degradation. This knockout model accelerates research into E3 ligase biology and B-cell malignancy therapeutics. For further details, technical inquiries, or to discuss custom requirements, please contact Ascent Research.
