ARF5 Knockout HAP1 Polyclonal Cells provide a heterogeneous CRISPR/Cas9-edited HAP1 cell population with targeted disruption of the ARF5 gene. This polyclonal knockout pool is designed for functional studies of ARF5-dependent trafficking, eliminating the need for single-cell cloning while offering a robust loss-of-function model. The cell population maintains biological diversity, making it suitable for genetic screens and pathway analyses where bulk knockout phenotypes are informative.
HAP1 is a near-haploid human chronic myeloid leukemia (CML) cell line derived from a male patient. It features a haploid karyotype except for disomy of chromosome 8 and an adherent fibroblastoid morphology. The haploid state permits efficient gene disruption through targeting of a single allele, minimizing genetic redundancy and facilitating unambiguous genotype?Cphenotype correlations in functional genomic studies.
ARF5 encodes a small GTPase that cycles between inactive GDP-bound and active GTP-bound states. Activated by ARF-GEFs including GBF1, BIG1, and BIG2 at Golgi membranes, ARF5 recruits COPI coatomer complexes??comprising COPA, COPB1, COPB2, and ARCN1??to drive retrograde vesicle formation from endosomes to the Golgi and intra-Golgi trafficking. ARF5 also interacts with ARFGAP1/2, GGA adaptors, and the KDEL receptor, linking GTPase regulation to cargo sorting and COPI assembly. This process is sensitive to brefeldin A and modulated by phosphatidylinositol 4-phosphate.
In the HAP1 background, ARF5 disruption yields a clean loss-of-function model with reduced compensation from other ARF isoforms, enabling clear dissection of retrograde transport and Golgi homeostasis. The knockout cells serve as a platform to investigate Golgi fragmentation, endosomal sorting defects, and consequences for cancer- or neurodevelopment-associated trafficking pathways. Rescue assays with ARF5 variants further allow structure-function analysis and inhibitor specificity testing.
Key applications include genetic screens for trafficking regulators, Golgi-to-ER retrieval studies, and drug target validation. Representative assays: immunofluorescence for Golgi markers (giantin, GM130), brefeldin A resistance, COPI recruitment, GFP-KDEL retrograde transport, and co-immunoprecipitation with COPI subunits. Flow cytometry for receptor recycling, western blotting, and RT-qPCR support validation of ARF5 disruption. For further information, contact Ascent Research.
