P4-ATPase flippases are transmembrane transport proteins that use ATP-hydrolysis to drive the movement of phospholipids from the extracellular- or lumenal-facing leaflet of a membrane bilayer to the cytosolic side. P4-ATPase flippases are generally thought to be heterodimers of an [α] subunit from the type IV P-ATPases and an accessory [β] subunit from the TMEM30 family. (Adapted from PMID:37200892.)