The PBK Knockout Raji Polyclonal Cells consist of a polyclonal population of Raji B lymphocytes engineered through CRISPR/Cas9-mediated gene disruption to eliminate expression of the PBK (PDZ-binding kinase/TOPK) gene. This loss-of-function model provides a defined genetic background for investigating PBK-dependent signaling pathways and cellular phenotypes in a human Burkitt lymphoma context.
Raji cells are a widely used human B lymphocyte line derived from a patient with Burkitt lymphoma and are Epstein-Barr virus (EBV)-positive. These cells retain key features of mature B cells, including antibody production and MHC class II-mediated antigen presentation, making them an established model for B-cell malignancies, EBV biology, and immunological studies. Their rapid growth and stable culture characteristics facilitate reproducible experimental manipulation.
PBK functions as a mitotic serine/threonine kinase that is transcriptionally regulated by E2F factors and activated downstream of growth factor signaling, such as EGF, and cyclin-dependent kinases. Upon activation during G2/M phase, PBK directly phosphorylates p38 MAPK, initiating a cascade that includes ATF2 and MAPKAPK2, and phosphorylates histone H3 at serine 10 to promote mitotic chromosome condensation and cytokinesis. PBK interacts with the PDZ-domain scaffold DLG1 and the Cdc2/cyclin B complex, integrating mitogenic signals to drive cell cycle progression. Disruption of PBK in Raji cells thus ablates a critical node in mitotic signaling, leading to impaired proliferation and elevated apoptosis.
In the Raji B-cell lymphoma model, PBK is frequently overexpressed and contributes to oncogenic transformation by sustaining unchecked mitotic entry and survival. Knockout of PBK in these cells disrupts the phosphorylation of downstream targets such as p38 MAPK and histone H3, resulting in G2/M arrest, reduced cell growth, and increased apoptosis. This makes the polyclonal PBK knockout Raji model particularly valuable for dissecting the molecular mechanisms underlying PBK-driven lymphomagenesis and for evaluating therapeutic strategies aimed at targeting mitotic kinases in B-cell cancers.
Researchers can utilize this model to validate PBK as a drug target in B-cell lymphomas via proliferation assays (MTT, colony formation) and apoptosis detection (Annexin V staining). Flow cytometry enables precise cell cycle profiling to assess mitotic defects, while Western blotting for phospho-p38 and phospho-histone H3, along with RT-qPCR, confirms disruption of downstream signaling. These cells are also suitable for functional genomics screens and for exploring PBK??s interplay with related oncogenic pathways, including Wnt/??-catenin signaling. For additional information or technical inquiries, please contact Ascent Research.
