The AP1S1 Knockout HEK293T Polyclonal Cells provide a ready-to-use CRISPR/Cas9-edited polyclonal knockout cell population for targeted disruption of the AP1S1 gene. This heterogeneous pool of HEK293T cells contains a variety of gene-editing outcomes, eliminating the need for single-cell cloning and enabling robust loss-of-function analysis. The cells are designed for studies of adaptor protein complex 1 (AP-1) and clathrin-mediated intracellular trafficking.
The host cell line, HEK293T, is a widely used human embryonic kidney epithelial line that stably expresses the SV40 large T-antigen, a modification that enhances episomal replication of plasmids carrying the SV40 origin of replication. This feature, combined with high transfectability and robust growth, makes HEK293T cells a leading platform for recombinant protein expression, lentiviral packaging, and biochemical trafficking assays.
AP1S1 encodes sigma1A, a subunit of the heterotetrameric AP-1 complex (together with AP1B1, AP1G1, AP1M1). AP-1 is recruited to the trans-Golgi network (TGN) by ARF1 GTPase, where it interacts with clathrin heavy chain (CLTC) to form coated vesicles. Sigma1A recognizes tyrosine-based YXX?? motifs on cargo proteins such as the cation-independent mannose 6-phosphate receptor (CI-MPR) and sortilin, directing their sorting into vesicles destined for the endosomal-lysosomal system. AP-1 functions upstream of RAB4A, RAB5A, and RAB11A, linking Golgi export to endocytic recycling and lysosomal delivery.
Loss of AP1S1 in HEK293T cells disrupts AP-1 complex assembly and function, leading to defective cargo sorting at the TGN, mislocalization of lysosomal integral membrane proteins, and impaired endosomal dynamics. This knockout model recapitulates cellular trafficking defects observed in MEDNIK syndrome, a rare neurodevelopmental disorder caused by mutations in AP1S1. The polyclonal composition avoids clonal biases and represents a broad spectrum of loss-of-function phenotypes, making it suitable for population-level studies.
Typical applications include Western blotting and immunofluorescence to monitor AP-1 subunit levels and localization, co-immunoprecipitation to examine complex integrity, and flow cytometry for quantifying surface cargo proteins. Live-cell imaging of fluorescent reporters such as CD8-CI-MPR chimeras allows real-time tracking of TGN-to-endosome trafficking. The cells are also suitable for drug screening campaigns targeting trafficking defects, functional genomics screens, and rescue experiments with wild-type or mutant AP1S1 constructs. For further details or to place an order, please contact Ascent Research.
