Autophagosome–lysosome fusion: PI s to the rescue

Phosphoinositides ( PI s), a small fraction of the cellular lipids, function in almost all cellular physiological processes and especially in intracellular membrane trafficking events. PI s play a critical role in autophagy, but only PI (3)P is well studied. In this issue of The EMBO Journal , Hasegawa et al (2016) identified INPP 5E, an inositol polyphosphate 5‐phosphatase, as a novel regulator of autophagy. INPP 5E controls the level of PI (3,5)P 2 at the lysosome and thereby locally regulates the actin cytoskeleton and autophagosome–lysosome fusion.