The HP1BP3 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population originating from the HT29 human colorectal adenocarcinoma cell line. This product provides a loss-of-function model for analyzing HP1BP3, a key chromatin organizer that functions in heterochromatin maintenance and DNA damage repair. The polyclonal format encompasses a mixed population of genetically disrupted cells, enabling robust pooled analyses of gene disruption effects without isolating individual clones. Suitable for investigating how HP1BP3 depletion reshapes chromatin architecture and cellular responses, this model serves as a versatile tool for colon cancer research.
HT29 cells are an established epithelial cell line derived from a primary colorectal adenocarcinoma in a 44-year-old female. These cells carry a TP53 mutation (R273H), an APC mutation, and maintain microsatellite stability (MSS). The genetic profile, including compromised p53 signaling and aberrant Wnt pathway activation, makes HT29 a widely used model for studying colon cancer biology, epithelial differentiation, and transport mechanisms. This background provides a disease-relevant context for probing the interplay between chromatin regulators and oncogenic signaling in colorectal tumorigenesis.
HP1BP3 acts as a molecular scaffold that coordinates heterochromatin organization and transcriptional silencing by interacting with HP1/CBX proteins (CBX1, CBX3, CBX5), BAZ2A/TIP5, the Lamin B receptor (LBR), and Histone H3, particularly at H3K9me3-enriched loci. It is regulated upstream by the DNA damage kinases ATM and ATR, as well as the transcription factors E2F1 and p53, positioning it at the intersection of chromatin dynamics and genome stability. Downstream, HP1BP3 influences the recruitment of DNA repair proteins such as RAD51 and BRCA1, which are essential for homologous recombination repair of double-strand breaks. Loss of HP1BP3 disrupts HP1-mediated chromatin compaction, impairs NoRC complex function, and compromises DNA damage repair fidelity, leading to increased genomic instability.
In the HT29 context, HP1BP3 knockout provides a powerful system to dissect how heterochromatin dysregulation contributes to colorectal cancer progression. The p53-mutant background, combined with APC loss, allows researchers to examine whether HP1BP3 disruption de-represses tumor suppressor genes or alters oncogenic transcription programs through relief of HP1-mediated silencing. Concurrently, defective homologous recombination repair sensitizes these cells to DNA-damaging agents, revealing potential synthetic lethality relationships. This model is thus instrumental for mechanistic studies linking chromatin architecture, DNA repair, and cancer cell survival.
These polyclonal knockout cells support diverse experimental workflows, including western blotting and RT-qPCR for HP1BP3 expression validation, immunofluorescence to monitor heterochromatin localization, and ChIP-qPCR to assess H3K9me3 enrichment at target loci. Transcriptomic changes can be profiled via RNA-seq, while functional consequences are evaluated through clonogenic survival assays following DNA damage, cell cycle analysis by flow cytometry, migration and invasion assays, and drug sensitivity testing using MTT-based viability assays. This model is well-suited for investigating chromatin dynamics in colorectal cancer, heterochromatin-mediated gene silencing, DNA damage response pathways, and preclinical drug testing. For additional information or technical support, please contact Ascent Research.
