APPL2 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma cell line, engineered to disrupt the adaptor protein APPL2. This polyclonal pool offers a heterogeneous loss-of-function model that preserves the diversity of editing outcomes across the cell population, enabling robust interrogation of APPL2-dependent phenotypes without the confounding effects of clonal selection. The cells are provided as a ready-to-use tool for studying signal transduction, endosomal trafficking, and colorectal cancer biology in a physiologically relevant epithelial context.
HT29 is a well-characterized human epithelial cell line originally isolated from a primary colorectal adenocarcinoma. It is widely used as a model system for intestinal epithelial physiology, drug absorption and transport studies, and colorectal cancer pathogenesis. HT29 cells exhibit an epithelial morphology, express mucins, and harbor mutations in key oncogenic pathways, including APC and p53, which drive constitutive Wnt/??-catenin signaling and genomic instability. These features make HT29 a powerful platform to examine the intersection of APPL2 function with oncogenic signaling networks.
APPL2 is a multifunctional adaptor protein that scaffolds Akt and the class IA PI3K p85 regulatory subunit on Rab5-positive early endosomes, thereby facilitating Akt recruitment and subsequent phosphorylation at Ser473 in response to insulin, EGF, and other growth factors. Through its PTB and PH domains, APPL2 interacts directly with the insulin receptor, IGF-1 receptor, and other receptor tyrosine kinases, linking endosomal compartments to downstream effector activation. APPL2 also binds Rab5 and the NuRD chromatin remodeling complex (including HDAC1, HDAC2, and MTA1) to couple endosomal trafficking with transcriptional regulation. In the Wnt/??-catenin pathway, APPL2 modulates signal strength by interacting with components such as TCF4 and influencing the expression of Wnt target genes including c-Myc and Cyclin D1. Consequently, APPL2 functions as a signaling node coordinating PI3K/Akt, insulin, Rab5-mediated endocytosis, and Wnt/??-catenin cascades.
In HT29 colorectal cancer cells, APPL2 disruption impairs insulin- and EGF-stimulated Akt activation, attenuates Wnt/??-catenin transcriptional activity, and reduces cell proliferation and survival. Because HT29 cells rely on constitutive Wnt signaling for growth, the APPL2 knockout model provides a unique opportunity to dissect the cross-talk between endosomal Akt activation and ??-catenin-dependent transcription in a genetically relevant background. The polyclonal nature of the knockout population captures a spectrum of loss-of-function effects, allowing researchers to study phenotypic heterogeneity and pathway dependencies without the bias of clonal selection.
This product is suitable for a wide range of applications, including dissection of APPL2-mediated signal transduction, high-throughput screening of pathway modulators, and validation of potential drug targets in colorectal cancer. Representative assays include western blotting for phospho-Akt (Ser473) to assess Akt signaling integrity, MTT/BrdU proliferation assays, flow cytometry for apoptosis using Annexin V/PI staining, co-immunoprecipitation of APPL2 with Rab5 or Akt2, immunofluorescence to visualize APPL1/APPL2 endosomal colocalization, TOPFlash luciferase reporter assays for Wnt activity, Transwell migration/invasion assays, and RT-qPCR for downstream targets such as c-Myc and Cyclin D1. For additional information, please contact Ascent Research.
