The APOBEC3F Knockout HeLa Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed for functional studies of the APOBEC3F cytidine deaminase. This loss-of-function model is generated by disrupting the APOBEC3F gene in HeLa cells, resulting in a mixed population of edited cells that collectively lack APOBEC3F expression. By using a polyclonal format, this product avoids clonal artifacts and better represents the heterogeneous nature of CRISPR-mediated gene disruption, making it suitable for population-based assays such as viral infectivity studies and bulk mutagenesis analyses.
The host cell line, HeLa, is an epithelial cell line derived from a cervical adenocarcinoma taken from Henrietta Lacks. These cells are immortalized and harbor human papillomavirus type 18 (HPV18) sequences, which drive their continuous proliferation. HeLa cells are a cornerstone of biomedical research, particularly in oncology and virology, due to their robust growth and ease of manipulation. Their HPV-positive status and epithelial origin make them a relevant model for studying viral-host interactions, including those involving oncogenic viruses and cellular restriction factors like the APOBEC3 family.
APOBEC3F functions as an interferon-inducible, single-stranded DNA cytidine deaminase that plays a pivotal role in the innate antiviral immune response. Its expression is upregulated by type I interferons (IFN-?? and IFN-??) through the JAK-STAT signaling cascade, involving interferon receptors (IFNAR), kinases JAK1 and TYK2, and transcription factors STAT1, STAT2, and IRF9, which promote transcription of interferon-stimulated genes (ISGs). Upon induction, APOBEC3F catalyzes the deamination of cytidine to uridine on exposed single-stranded DNA during reverse transcription of retroviruses like HIV-1, resulting in G-to-A hypermutation in nascent viral cDNA. This potent antiviral activity is counteracted by the HIV-1 Vif protein, which recruits an E3 ubiquitin ligase complex comprising CUL5, ELOB, ELOC, and the cofactor CBFB to target APOBEC3F for proteasomal degradation. APOBEC3F also interacts with APOBEC3G and is involved in restricting retrotransposon activity, further highlighting its broad role in safeguarding genomic integrity.
In the context of HeLa cells, APOBEC3F knockout provides a valuable tool for dissecting the specific contributions of this deaminase to innate antiviral defense and its potential off-target effects on host genome mutagenesis. Since HeLa cells are HPV-positive and exhibit deregulated cell cycle control, they serve as a platform to investigate how APOBEC3F activity might influence viral persistence or contribute to the mutation landscape observed in HPV-associated cancers. The polyclonal population allows researchers to assess overall trends in viral restriction without the confounding effects of single-cell heterogeneity, enabling robust comparisons between wild-type and APOBEC3F-deficient conditions.
This knockout model is ideal for a range of experimental applications, including investigation of HIV-1 restriction mechanisms through single-cycle infectivity assays and hypermutation sequencing to quantify G-to-A editing frequencies. Co-immunoprecipitation and confocal immunofluorescence can be employed to study the interaction between APOBEC3F and the Vif-E3 ligase complex, while RT-qPCR and western blotting confirm gene and protein ablation. Moreover, the cells can be used to explore APOBEC-mediated mutagenesis in cancer biology or to engineer cell lines with altered susceptibility to viral vectors for gene therapy research. For additional information or to request a quote, please contact Ascent Research.
