The CBX5 Knockout Jurkat Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population derived from the Jurkat T lymphoblast cell line, providing a loss-of-function model for the heterochromatin protein HP1??. This heterogeneous pool results from CRISPR/Cas9-mediated disruption of the CBX5 gene, enabling population-level studies of chromatin regulation in a T-cell leukemia background without clonal selection.
Jurkat cells are a widely used model of acute T-cell leukemia, originating from a patient with acute lymphoblastic leukemia. These immortalized T lymphoblasts maintain key T-cell receptor signaling and apoptotic pathways, making them ideal for dissecting oncogenic mechanisms and epigenetic control in hematologic malignancies, with high transfection efficiency supporting reproducible gene editing.
CBX5 (HP1??) recognizes H3K9me2/3 marks deposited by SUV39H1 and SUV39H2 methyltransferases, recruiting partners such as CAF-1 (CHAF1A), TIF1?? (TRIM28), and Lamin B receptor to promote chromatin compaction and transcriptional silencing. Upstream kinases Aurora B and PIM1 phosphorylate CBX5 to modulate chromatin affinity, while E2F transcription factors drive its expression. CBX5 represses E2F target genes, the IL-2 promoter, and telomeric repeats, contributing to genome stability and cell cycle arrest. It also interacts with HIV-1 integrase, implicating it in viral latency.
In the Jurkat context, CBX5 knockout facilitates investigation of heterochromatin-mediated gene silencing in T-cell leukemogenesis, DNA damage responses, and senescence. This model is particularly valuable for exploring interactions with E2F and PIM1 pathways that control proliferation and survival in acute lymphoblastic leukemia, and for studying how chromatin architecture influences TCR-driven apoptosis and epigenetic plasticity.
Applications include ChIP-qPCR for H3K9me3 mapping, immunofluorescence for heterochromatin foci, RNA-seq for transcriptional profiling, and co-immunoprecipitation for CBX5-associated complexes. Functional assays such as apoptosis detection, senescence-associated ??-galactosidase staining, and IL-2 reporter assays, as well as HIV latency experiments, can be performed. For technical inquiries, please contact Ascent Research.
