Phospholipase D and mTORC1: nutrients are what bring them together.

Mammalian target of rapamycin (mTOR) complex 1 (mTORC1) plays a central role in translating nutrient abundance into cell growth and proliferation. Although specific proteins have been described as mediators of this nutrient input, their mechanistic linkage remains incomplete. Two studies have added phospholipase D (PLD) as a mediator of nutrients to mTORC1. Furthermore, these studies link PLD and its product phosphatidic acid to previously identified activators of mTORC1 signaling, including the class III phosphoinositide-3 kinase, and provide evidence of the existence of two parallel nutrient-regulated pathways that converge on mTORC1 at late endosomes and/or lysosomes.