The role of PI3P phosphatases in the regulation of autophagy.

Autophagy initiation is strictly dependent on phosphatidylinositol 3-phosphate (PI3P) synthesis. PI3P production is under tight control of PI3Kinase, hVps34, in complex with Beclin-1. Mammalian cells express several PI3P phosphatases that belong to the myotubularin family. Even though some of them have been linked to serious human diseases, their cellular function is largely unknown. Two recent studies indicate that PI3P metabolism involved in autophagy initiation is further regulated by the PI3P phosphatases Jumpy and MTMR3. Additional pools of PI3P, upstream of mTOR and on the endocytic pathway, may modulate autophagy indirectly, suggesting that other PI3P phosphatases might be involved in this process. This review sums up our knowledge on PI3P phosphatases and discusses the recent progress on their role in autophagy. Published by Elsevier B.V.