The AP3B1 Knockout HEK293T Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the human AP3B1 gene, which encodes the ??3A subunit of the AP-3 adaptor complex. As a polyclonal pool, these cells contain heterogeneous gene disruptions, offering a loss-of-function model ideal for studying AP-3?Cdependent cargo sorting without requiring clonal isolation.
HEK293T cells are human embryonic kidney epithelial cells stably expressing SV40 large T antigen, widely utilized for high-level recombinant protein expression, virus production, and cell biology research. Their robust secretory pathway and well-characterized endolysosomal system make them a practical host for examining vesicle-mediated transport processes.
The ??3A subunit is a structural component of the heterotetrameric AP-3 complex, which sorts transmembrane cargo from the trans-Golgi network to lysosomes and lysosome-related organelles. AP-3 recognizes tyrosine-based (YXX??) and dileucine ([DE]XXXL[LI]) sorting motifs in cargo proteins such as LAMP1, LAMP2, CD63, and tyrosinase. Complex assembly requires interactions among AP-3 subunits (??/AP3D1, ??3/AP3S1, ??3/AP3M1) and recruitment factors including clathrin and ARF1 GTPase. Regulatory inputs from BLOC-1 and BLOC-2 complexes further modulate AP-3 function. Consequently, AP3B1 disruption impairs these interactions, leading to mis-sorting of lysosomal hydrolases, melanosomal proteins, and platelet dense granule constituents, and a block in organelle maturation.
In HEK293T cells, AP3B1 knockout provides a simplified model to dissect AP-3 pathways, as these cells contain the core endolysosomal trafficking machinery. The polyclonal configuration supports biochemical analyses requiring larger cell quantities, such as co-immunoprecipitation and subcellular fractionation, while enabling assays like immunofluorescence for LAMP1/CD63 localization and flow cytometry for surface CD63. This system is thus well-suited for mechanistic studies and modifier screens.
Primary applications include investigating the molecular etiology of Hermansky-Pudlak syndrome type 2 (oculocutaneous albinism, bleeding diathesis, immunodeficiency), lysosomal storage disorders, and pigmentation biology through tyrosinase trafficking. Researchers can perform lysosomal enzyme activity assays, cargo-trafficking reporter constructs, and evaluate platelet dense granule cargo sorting in a reconstituted setting. For further information or custom CRISPR-edited products, please contact Ascent Research.
