The CUL4B Knockout Raji Polyclonal Cells are a polyclonal population of Raji B lymphoblastoid cells engineered using CRISPR/Cas9 to disrupt the CUL4B gene. This gene-edited pool provides a robust loss-of-function model for investigating CUL4B-mediated processes without introducing clonal biases, making it suitable for population-level functional studies in a B-lymphoma background.
The Raji cell line, an EBV-positive B lymphoblastoid line established from a Nigerian patient with Burkitt’s lymphoma, grows in suspension and exhibits mature B-cell markers. It is widely employed to study B-cell biology, lymphomagenesis, and immune signaling, and its genetic accessibility facilitates efficient CRISPR/Cas9 editing and subsequent phenotypic analyses.
CUL4B functions as a scaffold protein for the Cullin4B-RING E3 ubiquitin ligase (CRL4B). Upon neddylation by the E1/E2 enzymes NAE1/UBA3 and UBE2M, CRL4B engages substrate receptors such as DDB2 and WDR5 to ubiquitinate targets. Key substrates include the cell cycle inhibitor p21, the ubiquitin ligase MDM2, the DNA damage recognition factor DDB2, and the replication licensing factor CDT1, whose degradation regulates proliferation and genomic stability. CRL4B also mediates monoubiquitination of histone H2A to enforce epigenetic gene silencing. Upstream, DNA damage sensors ATM/ATR activate CRL4B, while the COP9 signalosome dynamically controls neddylation. Through these interactions, CUL4B integrates DNA damage repair, cell cycle progression, and chromatin regulation.
In Raji B cells, CUL4B knockout enables targeted dissection of CRL4B-dependent ubiquitination in a hematologic malignancy context. Because CUL4B is implicated in diverse cancers and neurodevelopmental disorders, this model permits investigation of how its loss alters downstream effectors like p21 and MDM2, influencing cell cycle checkpoints, apoptosis, and DNA damage response pathways. The EBV-positive status of Raji cells further allows exploration of potential crosstalk between viral latency programs and host ubiquitin signaling in lymphomagenesis.
Key experimental uses include Western blotting for CUL4B, p21, and MDM2; in vivo ubiquitination assays; flow cytometry for cell cycle and apoptosis profiles; RT-qPCR for gene expression changes; ??H2AX immunofluorescence to assess DNA damage; drug sensitivity screens; and transcriptomic analysis via RNA-seq. For further information or assistance, please contact Ascent Research.
