CBX4 Knockout HEK293T Polyclonal Cells are a CRISPR/Cas9-edited human polyclonal knockout cell population designed for loss-of-function studies of the CBX4 gene. The polyclonal format ensures efficient target gene disruption across a heterogeneous cell pool, providing a reliable model without clonal isolation. This knockout tool facilitates reproducible investigation of CBX4-mediated processes in a well-established cellular background.
The host HEK293T cell line is derived from human embryonic kidney cells transformed with adenovirus 5 DNA and stably expresses the SV40 large T antigen. HEK293T cells are widely used for high-level recombinant protein expression and genome editing due to their high transfectability and robust proliferation. These characteristics make them an ideal chassis for generating CRISPR-edited knockout populations, suitable for diverse biochemical and cell-based assays.
CBX4 encodes a SUMO E3 ligase that functions as a core component of Polycomb Repressive Complex 1 (PRC1). It catalyzes SUMOylation of key substrates, including SMAD4 and CtBP, leading to transcriptional silencing and chromatin compaction. CBX4 is regulated by upstream signals such as p53, MYC, TGF-??, and hypoxia, and it controls downstream targets like p21/CDKN1A, p16/CDKN2A, and HIPK2. Through interactions with PRC1 subunits BMI1, RING1B, and PHC, along with the E2 enzyme UBC9, CBX4 orchestrates SUMO-dependent transcriptional repression. It critically modulates cellular senescence and stem cell maintenance by influencing p53 and p16 pathways.
In the HEK293T background, where p53 function is attenuated by SV40 T antigen, CBX4 knockout provides a clean model for examining PRC1-mediated gene silencing and SUMOylation dynamics. This system allows dissection of CBX4’s role in senescence bypass, chromatin remodeling, and oncogenic transformation, particularly relevant to hepatocellular carcinoma and breast cancer research. The knockout cells facilitate investigation of how loss of CBX4 impacts proliferation, tumor suppressor gene regulation, and SUMO-dependent signaling networks.
Applications include Western blotting and RT-qPCR for expression analysis, co-immunoprecipitation and ChIP-qPCR for protein-DNA interaction studies, and SUMOylation assays to assess ligase activity. Senescence-associated ??-galactosidase staining and cell proliferation assays can evaluate phenotypic outcomes. These polyclonal knockout cells support drug screening and functional probing of the PRC1 pathway and senescence regulation. For further information, contact Ascent Research.
