The ARF1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 human near-haploid cell line, engineered to disrupt the ARF1 gene without clonal selection. This polyclonal pool contains a heterogeneous mixture of ARF1-targeted alleles generated by CRISPR/Cas9-mediated gene disruption, providing a robust loss-of-function model for studying ARF1-dependent processes in a population-based format.
HAP1 is a haploid human cell line originally derived from the KBM-7 chronic myeloid leukemia line; it retains a haploid karyotype except for disomy of chromosome 8. This genetic background ensures that single-allele gene inactivation typically yields a null phenotype, simplifying the interpretation of knockout studies. As a myeloid progenitor-derived line, HAP1 is particularly relevant for investigations into hematopoietic malignancies and intracellular trafficking pathways.
ARF1 functions as a small GTPase switch controlling coat protein assembly and vesicle budding at Golgi and endosomal membranes. It cycles between an inactive GDP-bound and active GTP-bound state, undergoing activation by guanine nucleotide exchange factors including GBF1, BIG1, and BIG2. Active ARF1-GTP recruits COPI coatomer, clathrin adaptors AP-1 and AP-3, and GGAs to initiate vesicle formation, and stimulates phospholipase D1 (PLD1) and PIP5K1A to produce lipid second messengers that modulate actin dynamics via effectors such as arfaptin. GTP hydrolysis is catalyzed by ARFGAP1 and ARFGAP2. Key interacting proteins include COPB1, AP1G1, and ASAP1. Through these molecular interactions, ARF1 governs intra-Golgi transport, endosomal-to-TGN retrieval, endocytosis, and lipid droplet metabolism.
In the HAP1 context, ARF1 disruption leads to profound defects in Golgi architecture and membrane trafficking, offering a clean genetic background to dissect COPI-dependent transport and Golgi ribbon maintenance. The haploid nature of the cells ensures unambiguous knockout phenotypes, facilitating the mapping of functional relationships between ARF1 and its upstream GEFs or downstream effectors without interference from wild-type alleles.
These polyclonal knockout cells are suited for a range of applications, including immunofluorescence microscopy to assess Golgi marker redistribution, VSVG-GFP trafficking assays to measure secretion kinetics, co-immunoprecipitation of ARF1 effectors (e.g., COPB1), and Western blotting for ARF1 and downstream targets. Further uses encompass small-molecule inhibitor screening, analysis of viral replication (influenza, HIV), and lipidomic profiling of phospholipid changes. For additional information, please contact Ascent Research.
