The CBX8 Knockout HEK293T Polyclonal Cells from Ascent Research is a CRISPR/Cas9-edited polyclonal knockout cell population targeting the CBX8 gene. This product provides a loss-of-function model for studying the role of CBX8 in Polycomb repressive complex 1 (PRC1) function and epigenetic gene regulation. The polyclonal knockout cells are generated by CRISPR/Cas9-mediated disruption of the human CBX8 gene, resulting in a mixed population of cells with heterogeneous editing outcomes. This format avoids clonal selection bias and enables pooled screening approaches while maintaining representative genomic diversity.
The HEK293T host cell line is derived from human embryonic kidney epithelial cells and stably expresses the SV40 large T antigen. This transformation allows episomal replication of plasmids containing the SV40 origin of replication, making these cells highly transfectable and suitable for a wide range of biochemical and genomic assays. HEK293T cells provide a robust and well-characterized background for generating knockout models, enabling reproducible experiments in chromatin biology, transcriptional regulation, and cancer research. Their rapid growth and ease of manipulation further support high-throughput applications.
CBX8 is a core component of canonical PRC1, which is recruited to chromatin by recognition of H3K27me3 marks deposited by PRC2. Within the PRC1 complex, CBX8 interacts with RING1B and other PCGF proteins to catalyze monoubiquitination of histone H2A at lysine 119 (H2AK119ub1), a modification that promotes chromatin compaction and transcriptional silencing of target genes. CBX8 is directly involved in repressing key tumor suppressors such as CDKN2A (p16INK4a) and CDKN1A (p21), thereby regulating cellular senescence, stem cell maintenance, and proliferation. Upstream, CBX8 activity is modulated by EZH2 and SUZ12, and its downstream effects are mediated through RING1B-dependent H2AK119ub1 deposition. Disruption of CBX8 therefore perturbs the PRC1-mediated silencing axis, offering a valuable tool to dissect these epigenetic mechanisms.
In HEK293T cells, the loss of CBX8 disrupts PRC1 complex assembly and attenuates H2AK119ub1 deposition, leading to derepression of CDKN1A and CDKN2A and consequent effects on cell cycle progression and senescence. Because HEK293T cells express SV40 large T antigen, they offer a unique context to study how Polycomb-mediated silencing interfaces with viral oncoprotein-driven transformation. This knockout model enables investigation of CBX8-dependent regulation of proliferation and differentiation pathways in a rapidly proliferating, non-cancerous epithelial background. Researchers can use these cells to evaluate how PRC1 dysfunction contributes to tumorigenesis by monitoring changes in gene expression and histone modifications.
The CBX8 Knockout HEK293T Polyclonal Cells are ideally suited for a range of research applications, including cancer epigenetics, chromatin biology, and drug screening for epigenetic modulators. Typical assays include western blotting to confirm CBX8 depletion, RT-qPCR to measure derepression of CDKN2A and CDKN1A, RNA-seq for global transcriptome analysis, and ChIP-qPCR to assess H2AK119ub1 and H3K27me3 levels at target loci. Co-immunoprecipitation can be used to examine PRC1 complex integrity, while proliferation and cell cycle analyses reveal functional consequences of CBX8 loss. Reporter assays further enable dissection of gene repression mechanisms. For additional information, please contact Ascent Research.
