The RLIG1 Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited loss-of-function cell pool targeting the RLIG1 gene (encoding RIG-I) in the HAP1 near-haploid human cell line. This polyclonal knockout population provides a genetically disrupted background for investigating RIG-I-dependent innate immune signaling without the need for single-cell cloning. The targeted gene disruption enables researchers to ablate RIG-I protein expression and assess functional consequences in a robust cellular system.
HAP1 cells are a near-haploid derivative of the KBM-7 chronic myeloid leukemia (CML) line, characterized by a single copy of most chromosomes (except the second copy of chromosome 8). This near-haploid karyotype simplifies loss-of-function studies because knockout of a single allele typically leads to complete disruption of gene function in the majority of cells. As a result, HAP1 cells have become a preferred model for functional genomics, large-scale genetic screens, and the generation of knockout models across diverse biological pathways.
RLIG1 encodes the retinoic acid-inducible gene I (RIG-I) protein, a cytoplasmic pattern recognition receptor that detects viral double-stranded RNA (dsRNA) bearing 5??-triphosphate moieties. Upon ligand binding and TRIM25-mediated ubiquitination, RIG-I undergoes conformational changes and interacts with the mitochondrial antiviral-signaling protein MAVS (IPS-1). This interaction triggers a signaling cascade involving the kinases TBK1 and IKK??, which phosphorylate the transcription factors IRF3 and IRF7. Phosphorylated IRF3/IRF7 translocate to the nucleus and induce expression of type I interferons (such as IFN-??) and interferon-stimulated genes (ISGs), establishing an antiviral state. RIG-I activity is further modulated by regulatory factors including CK2, RNF125, USP3, HSP90, and 14-3-3 proteins, ensuring tight control of innate immune responses.
Disruption of RLIG1 in the HAP1 near-haploid context provides a powerful platform for dissecting RIG-I-mediated innate immune signaling and its crosstalk with other pathways. Because HAP1 cells lack a second functional allele for most genes, RLIG1 knockout eliminates a major sensor for cytoplasmic viral RNA, enabling unambiguous attribution of phenotypes to RIG-I loss. This model is particularly valuable for studying signal transduction from MAVS to IRF3/IRF7 activation, exploring roles of RIG-I in antiviral defense, autoimmune disorders such as Singleton-Merten syndrome, and interferonopathies. The polyclonal nature ensures representation of diverse editing outcomes while maintaining a high penetrance of functional knockout across the population.
Researchers can employ RLIG1 Knockout HAP1 Polyclonal Cells in a wide array of experimental applications, including viral infection assays to evaluate RIG-I-dependent antiviral responses, luciferase reporter assays for IFN-?? promoter activation, RT-qPCR profiling of ISG induction, and enzyme-linked immunosorbent assays (ELISA) for cytokine secretion. Western blotting and immunofluorescence are routinely used to confirm loss of RIG-I protein and assess activation states of downstream effectors such as MAVS, TBK1, and phosphorylated IRF3. These cells also serve as an ideal parental line for rescue experiments and for screening small-molecule modulators of the RLR pathway. For additional details or custom configurations, please contact Ascent Research.
