Abstract
The AP-1 adaptor complex is found in all eukaryotes, but it has been implicated in different pathways in different organisms. To look directly at AP-1 function, we generated stably transduced HeLa cells coexpressing tagged AP-1 and various tagged membrane proteins. Live cell imaging showed that AP-1 is recruited onto tubular carriers trafficking from the Golgi apparatus to the plasma membrane, as well as onto transferrin-containing early/recycling endosomes. Analysis of single AP-1 vesicles showed that they are a heterogeneous population, which starts to sequester cargo 30 min after exit from the ER. Vesicle capture showed that AP-1 vesicles contain transmembrane proteins found at the TGN and early/recycling endosomes, as well as lysosomal hydrolases, but very little of the anterograde adaptor GGA2. Together, our results support a model in which AP-1 retrieves proteins from post-Golgi compartments back to the TGN, analogous to COPI’s role in the early secretory pathway. We propose that this is the function of AP-1 in all eukaryotes.
Original language | English |
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Article number | e202310071 |
Journal | The Journal of cell biology |
Volume | 223 |
Issue number | 7 |
DOIs | |
Publication status | Published - 5 Apr 2024 |
Keywords
- Organelles
- Trafficking
- Membrane Proteins/metabolism
- trans-Golgi Network/metabolism
- Cell Membrane/metabolism
- Humans
- Golgi Apparatus/genetics
- HeLa Cells
- Adaptor Proteins, Vesicular Transport/metabolism
- Endosomes/genetics
- Transcription Factor AP-1/genetics
- Protein Transport