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.