The FBXO28 Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population of Raji B lymphocytes with targeted disruption of the FBXO28 gene. This heterogeneous knockout pool provides a loss-of-function model for studying FBXO28-dependent processes without clonal selection artifacts. The polyclonal format maintains diverse editing outcomes while effectively reducing FBXO28 function across the population, suitable for bulk assays in B-cell contexts.
The Raji cell line, a Burkitt lymphoma-derived B lymphoblastoid line, is Epstein-Barr virus (EBV)-positive and retains features of germinal center B cells, including antibody production and antigen presentation. Constitutively active NF-??B signaling in Raji cells drives proliferation and survival, making them a rigorous model for B-cell lymphoma and immune signaling research. This host background is especially relevant for investigating ubiquitin-dependent regulation of NF-??B.
FBXO28 functions as the substrate recognition subunit of the SCF (SKP1-CUL1-RBX1) E3 ubiquitin ligase complex, targeting the atypical NF-??B inhibitor I??BNS (NFKBID) for K48-linked polyubiquitination and proteasomal degradation. By degrading I??BNS, FBXO28 relieves inhibition of NF-??B dimers such as p65/p50, enabling their nuclear translocation and transcription of pro-survival genes including BCL2, MYC, and CCND1. This axis is activated by upstream TNF??, IL-1??, and LPS, which signal through the IKK complex (IKBKG/IKBKB/CHUK). Thus, FBXO28 links the ubiquitin-proteasome system to NF-??B transcriptional regulation.
In the context of Raji B cells, FBXO28-mediated degradation of I??BNS further amplifies the already heightened NF-??B activity driven by EBV oncoproteins. Disrupting FBXO28 in this polyclonal knockout model allows dissection of SCF ligase contributions to B-cell survival and proliferation. The mixed population better reflects tumor heterogeneity and enables robust assessment of NF-??B target gene expression, cytokine output, and apoptotic sensitivity in a lymphomagenic background.
These polyclonal knockout cells are ideal for Western blot analysis of I??BNS and phospho-p65, NF-??B luciferase reporter assays, and ubiquitination co-IP to probe SCF complex interactions. RT-qPCR for BCL2, MYC, and CCND1 reveals transcriptional outcomes, while flow cytometry measures apoptosis and viability. Applications include investigating NF-??B regulation in B-cell lymphoma, screening FBXO28 substrates, and validating FBXO28 as a therapeutic target in oncology and autoimmunity. For inquiries, contact Ascent Research.
