PT - JOURNAL ARTICLE AU - Jennifer Hirst AU - Geoffrey G. Hesketh AU - Anne-Claude Gingras AU - Margaret S. Robinson TI - Rag GTPases and Phosphatidylinositol 3-Phosphate Mediate Recruitment of the AP-5/SPG11/SPG15 Complex AID - 10.1101/2020.10.27.357723 DP - 2020 Jan 01 TA - bioRxiv PG - 2020.10.27.357723 4099 - http://biorxiv.org/content/early/2020/10/28/2020.10.27.357723.short 4100 - http://biorxiv.org/content/early/2020/10/28/2020.10.27.357723.full AB - Adaptor protein complex 5 (AP-5) and its partners, SPG11 and SPG15, are recruited onto late endosomes and lysosomes. Here we show that recruitment of AP-5/SPG11/SPG15 is enhanced in starved cells, and occurs by coincidence detection, requiring both phosphatidylinositol 3-phosphate (PI3P) and Rag GTPases. PI3P binding is via the SPG15 FYVE domain, which on its own localises to early endosomes. GDP-locked RagC promotes recruitment of AP-5/SPG11/SPG15 while GTP-locked RagA prevents its recruitment. Our results uncover an interplay between AP-5/SPG11/SPG15 and the mTORC1 pathway, and help to explain the phenotype of AP-5/SPG11/SPG15 deficiency in patients, including the defect in autophagic lysosome reformation.Summary The AP-5/SPG11/SPG15 complex is recruited onto late endosomes/lysosomes, and contributes to lysosomal homeostasis and autophagic lysosome reformation. Hirst et al. show that recruitment is by coincidence detection, requiring both phosphatidylinositol 3-phosphate and Rag GTPases, thus uncovering a link between AP-5/SPG11/SPG15 and the mTORC1 pathway.Competing Interest StatementThe authors have declared no competing interest.