The ASF1A Knockout HT29 Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal population derived from HT29 human colorectal adenocarcinoma cells, designed to disrupt the ASF1A gene. This loss-of-function model enables investigation of ASF1A??s role in nucleosome assembly, DNA replication, and chromatin dynamics. The polyclonal format minimizes clonal biases and provides a heterogeneous knockout background suitable for robust functional studies. As a genetically perturbed population, these cells are valuable for exploring ASF1A-mediated pathways without the need for single-cell cloning.
The parental HT29 cell line originates from a primary colorectal adenocarcinoma in a 44-year-old female and serves as a well-established intestinal epithelial model. These cells exhibit epithelial morphology and retain the capacity to differentiate, making them useful for studying colorectal cancer biology, barrier function, and drug responses. Their relevance to colorectal adenocarcinoma research is underscored by widespread use in tumorigenesis and metastasis studies. Knocking out ASF1A in this background permits dissection of histone chaperone functions within a clinically pertinent cancer context.
ASF1A is a histone H3-H4 chaperone that mediates nucleosome assembly and disassembly. Its activity is regulated by upstream factors such as E2F1, ATM, ATR, and CDK2, and it interacts with histones H3 and H4, delivering them to the CAF-1 complex (CHAF1A, CHAF1B, RBBP4) for replication-coupled deposition and to the HIRA complex for replication-independent chromatin assembly. Additionally, ASF1A associates with MCM2, MCM3, and PCNA to coordinate replication fork progression. Through these interactions, ASF1A bridges histone supply with DNA replication, transcription regulation, and DNA damage repair. Disruption of ASF1A impairs these processes, causing chromatin defects and genomic instability.
In HT29 colorectal cancer cells, ASF1A knockout leads to defective chromatin assembly, inducing DNA replication stress, heightened genomic instability, and altered gene expression profiles. Because cancer cells depend on precise chromatin maintenance for proliferation, ASF1A loss exacerbates chromosomal instability??a driver of colorectal cancer progression. This model thus enables study of how histone chaperone dysfunction contributes to tumorigenesis, drug sensitivity, and metastatic behavior, providing a platform for probing chromatin-related vulnerabilities in colorectal carcinoma.
These polyclonal knockout cells support diverse applications, including chromatin dynamics investigation, replication stress analysis, and colorectal cancer genomics. Compatible assays include Western blot for ASF1A and ??H2AX, RT-qPCR for downstream targets, immunofluorescence for histone marks, flow cytometry for cell cycle distribution, DNA fiber assays for replication fork integrity, and comet assays for DNA damage. They are also suited for anti-cancer drug screening targeting chromatin remodeling or replication stress pathways. For further information, contact Ascent Research.
