The IFT88 Knockout 769-P Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population targeting the IFT88 gene in the human 769-P renal cell carcinoma line. This pooled format captures diverse IFT88 disruptions, providing a loss-of-function model free from clonal isolation bias. The polyclonal nature allows robust assessment of ciliary biology and signaling while maintaining the tumor cell context.
The 769-P line originates from a clear cell renal cell carcinoma with a homozygous VHL mutation, leading to constitutive HIF stabilization and pseudohypoxic signaling. This background exhibits altered ciliary dynamics, including reduced ciliation, making it relevant for studying cilia-dependent pathways in renal cancer. The VHL-HIF axis intersects with ciliary function, as the primary cilium orchestrates key signaling cascades.
IFT88 is a core IFT-B complex component that drives anterograde ciliary transport complexed with kinesin-2 motors (KIF3A/KIF3B/KAP). Regulated by RFX3, FOXJ1, and DZIP1, IFT88 mediates delivery of ciliary cargo essential for axonemal assembly and localization of receptors like SMO and PTCH1. Downstream, it promotes Hedgehog signaling through GLI transcription factor activation and modulates Wnt/??-catenin pathways via ciliary ??-catenin processing. Its function depends on interactions with IFT46, IFT52, IFT57, IFT81, and coordination with IFT-A, dynein, and the BBSome.
In 769-P cells, IFT88 knockout disrupts IFT-B function, abolishing primary cilium formation and crippling ciliary-organized signal transduction. Hedgehog pathway signaling is attenuated due to impaired SMO trafficking and GLI activation, while Wnt/??-catenin dynamics are perturbed. Given the VHL-mutant context, these defects intersect with HIF-driven oncogenic programs, making the model invaluable for dissecting ciliary contributions to proliferation, migration, and drug responses in ccRCC.
Typical applications include immunofluorescence imaging for ciliary markers (acetylated ??-tubulin, Arl13b) to assess ciliation, combined with western blot confirmation of IFT88 loss. Hedgehog pathway activity can be measured using Gli luciferase reporters, and IFT-B complex integrity probed by co-immunoprecipitation. Functional studies encompass migration and proliferation assays to characterize cilia-dependent phenotypes. The cells also facilitate drug discovery for cilia-related diseases and ciliopathy modeling. For support, please contact Ascent Research.
