The APOBEC3C Knockout Jurkat Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal human T lymphocyte population containing a targeted disruption of the APOBEC3C gene. This product provides a genetically heterogeneous pool of Jurkat cells, each carrying unique insertions or deletions at the APOBEC3C locus, collectively leading to loss of functional APOBEC3C protein. Designed for researchers in immunology, virology, and cancer biology, these polyclonal knockout cells serve as a powerful loss-of-function model to dissect the multifaceted roles of APOBEC3C in cellular defense mechanisms and genome integrity. As a polyclonal population, they offer robust and reproducible results in downstream applications without the need for monoclonal isolation, enabling straightforward incorporation into existing experimental workflows.
Hosted in the Jurkat E6-1 cell line, an immortalized human T lymphocyte originally derived from the peripheral blood of a patient with acute T cell leukemia, these knockout cells retain key features of CD4+ T cells. The Jurkat line is a cornerstone model for studying T cell activation, signal transduction downstream of the T cell receptor, and apoptosis. Because Jurkat cells are natural targets for HIV-1 infection due to expression of CD4 and co-receptors, they are exceptionally well-suited for investigating host restriction factors that counteract retroviruses. The TCR-proximal signaling machinery and robust interferon responsiveness of Jurkat cells further enable detailed probing of antiviral innate immune pathways, making this knockout model highly relevant for mechanistic studies of APOBEC3C in a physiologically authentic T cell environment.
APOBEC3C is a single-stranded DNA cytosine deaminase that catalyzes C-to-U editing and functions as a potent restriction factor against retroviruses such as HIV-1, as well as retrotransposons like LINE-1. It is transcriptionally and post-translationally regulated by type I and type II interferon signaling through the JAK-STAT axis; key drivers include IRF1, STAT1, STAT2, and NF-??B. Upon viral infection, APOBEC3C is incorporated into budding virions and, during reverse transcription, deaminates cytosines in nascent minus-strand viral cDNA, leading to lethal G-to-A hypermutations. However, HIV-1 encodes the accessory protein Vif, which hijacks a host Cullin5-RBX2-ElonginB/C E3 ubiquitin ligase to polyubiquitinate APOBEC3C, targeting it for proteasomal degradation and thereby evading restriction. The deaminase also has off-target activity on host genomic DNA at replication forks, and the resulting uracil lesions are processed by uracil-DNA glycosylase (UNG) and AP endonuclease 1 (APE1), contributing to APOBEC mutational signatures prevalent in breast, lung, bladder, and head and neck cancers.
Eliminating APOBEC3C in Jurkat cells allows researchers to directly assess its contribution to the antiviral state in T lymphocytes. In the absence of APOBEC3C, HIV-1 should replicate more efficiently, providing a clean background for reconstitution experiments and for studying viral Vif-mediated evasion. Moreover, because APOBEC3C can also act on host DNA, this knockout model is invaluable for investigating the balance between innate immunity and genomic instability??a delicate trade-off that may drive mutagenesis and tumor evolution in cancer. The Jurkat background additionally permits cross-talk studies with other APOBEC family members and with interferon-induced pathways, helping to delineate the specific versus overlapping functions of these cytidine deaminases in immune defense and disease pathogenesis.
The APOBEC3C Knockout Jurkat Polyclonal Cells are suitable for a broad range of applications. Typical assays include HIV-1 single-cycle infectivity assays to quantify differences in viral replication between wild-type and knockout cells, Western blotting to monitor APOBEC3C and Vif protein levels, and sequencing-based hypermutation analysis to assess G-to-A editing frequencies in proviral DNA. The cells can also be used in co-immunoprecipitation studies to map interactions between APOBEC3C and the Vif-E3 ligase complex, RT-qPCR to measure transcript levels of APOBEC3C and interferon-stimulated genes, and deaminase activity assays with ssDNA substrates. Beyond HIV restriction, the model enables investigation of retrotransposon control, cancer-relevant APOBEC-mediated mutagenesis at genomic DNA, and validation of small-molecule inhibitors targeting the Vif-APOBEC3C axis as potential therapeutics. For additional information or technical support, please contact Ascent Research.
