Secretory Vesicle Polar Sorting, Endosome Recycling and Cytoskeleton Organization Require the AP-1 Complex in .

Citation:

Martzoukou O, Diallinas G, Amillis S. Secretory Vesicle Polar Sorting, Endosome Recycling and Cytoskeleton Organization Require the AP-1 Complex in . Genetics. 2018.

Abstract:

The AP-1 complex is essential for membrane protein traffic via its role in the pinching-off and sorting of secretory vesicles from the trans-Golgi and/or endosomes. While its essentiality is undisputed in metazoa, its role in simpler eukaryotes seems less clear. Here we dissect the role of AP-1 in the filamentous fungus and show that it is absolutely essential for growth due to its role in clathrin-dependent maintenance of polar traffic of specific membrane cargoes towards the apex of growing hyphae. We provide evidence that AP-1 is involved in both anterograde sorting of RabE-labeled secretory vesicles and RabA/B-dependent endosome recycling. Additionally, AP-1 is shown to be critical for microtubule and septin organization, further rationalizing its essentiality in cells that face the challenge of cytoskeleton-dependent polarized cargo traffic. This work also opens a novel issue on how non-polar cargoes, such as transporters, are sorted to the eukaryotic plasma membrane.