The AP-1 clathrin adaptor has a conserved role in recycling resident proteins of the trans-Golgi network
Abstract
Although the AP-1 clathrin adaptor has been studied for decades, its role in membrane trafficking has been ambiguous. Here, we systematically investigated the localization and function of mammalian AP-1. This adaptor associates with the trans-Golgi network (TGN) and with TGN-related recycling endosomes. Disruption of the 1A subunit of AP-1 has only a mild effect on the Golgi export of secretory cargoes, but it causes depletion from the Golgi of multiple transmembrane TGN proteins. Live-cell imaging and a cell surface labeling assay indicate that when TGN proteins are unable to bind AP-1, they exit the Golgi to the plasma membrane. Our interpretation is that the vesicles generated with AP-1 recycle transmembrane TGN proteins, thereby keeping those proteins in the Golgi during cisternal maturation. The clathrin adaptor epsinR seems to function as a partner for AP-1 in recycling a subset of TGN proteins. These results closely align with studies of AP-1 function in yeast, suggesting that the conserved core role of AP-1 is the intra-Golgi recycling of TGN proteins.
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BibTeX
@misc{valbuena2026clathrin,
title = {{The AP-1 clathrin adaptor has a conserved role in recycling resident proteins of the trans-Golgi network}},
author = {Fernando M. Valbuena and Maddison Lessard and Adam H. Krahn and Areti Pantazopoulou and Conor F. Lee-Smith and J. Christopher Fromme and Petia Adarska and Francesca Bottanelli and Benjamin S. Glick},
howpublished = {bioRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.21.760840},
url = {https://www.biorxiv.org/content/10.64898/2026.10.21.760840v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - The AP-1 clathrin adaptor has a conserved role in recycling resident proteins of the trans-Golgi network
AU - Fernando M. Valbuena
AU - Maddison Lessard
AU - Adam H. Krahn
AU - Areti Pantazopoulou
AU - Conor F. Lee-Smith
AU - J. Christopher Fromme
AU - Petia Adarska
AU - Francesca Bottanelli
AU - Benjamin S. Glick
PY - 2026
DA - 2026/10/21
PB - bioRxiv
DO - 10.64898/2026.10.21.760840
UR - https://www.biorxiv.org/content/10.64898/2026.10.21.760840v1
AB - Although the AP-1 clathrin adaptor has been studied for decades, its role in membrane trafficking has been ambiguous. Here, we systematically investigated the localization and function of mammalian AP-1. This adaptor associates with the trans-Golgi network (TGN) and with TGN-related recycling endosomes. Disruption of the 1A subunit of AP-1 has only a mild effect on the Golgi export of secretory cargoes, but it causes depletion from the Golgi of multiple transmembrane TGN proteins. Live-cell imaging and a cell surface labeling assay indicate that when TGN proteins are unable to bind AP-1, they exit the Golgi to the plasma membrane. Our interpretation is that the vesicles generated with AP-1 recycle transmembrane TGN proteins, thereby keeping those proteins in the Golgi during cisternal maturation. The clathrin adaptor epsinR seems to function as a partner for AP-1 in recycling a subset of TGN proteins. These results closely align with studies of AP-1 function in yeast, suggesting that the conserved core role of AP-1 is the intra-Golgi recycling of TGN proteins.
SN - 2692-8205
ER -