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The phosphatidylinositol (4,5)-bisphosphate-Rab35 axis regulates migrasome formation
Tianlun Ding1 , Jinyao Ji2 , Weiying Zhang3 , Yuheng Liu1 , Boqi Liu1 , Yiyang Han1 , Chunlai Chen2 , Li Yu1,*1State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China
Migrasomes are recently discovered organelles, which are formed on the ends or branch points of retraction fibers at the trailing edge of migrating cells. Previously, we showed that recruitment of integrins to the site of migrasome formation is essential for migrasome biogenesis. In this study, we found that prior to migrasome formation, PIP5K1A, a PI4P kinase which converts PI4P into PI(4,5)P2, is recruited to migrasome formation sites. The recruitment of PIP5K1A results in generation of PI(4,5)P2 at the migrasome formation site. Once accumulated, PI(4,5)P2 recruits Rab35 to the migrasome formation site by interacting with the C-terminal polybasic cluster of Rab35. We further demonstrated that active Rab35 promotes migrasome formation by recruiting and concentrating integrin α5 at migrasome formation sites, which is likely mediated by the interaction between integrin α5 and Rab35. Our study identifies the upstream signaling events orchestrating migrasome biogenesis.