Plays a role in regulating membrane trafficking of cargo proteins, namely endosome to plasma membrane recycling, probably acting through RAB5 and RAB11 activation ( ). Also involved in endosome to trans-Golgi network retrograde transport (, ). In complex with MON2 and DOP1B, regulates SNX3 retromer-mediated endosomal sorting of WLS, a transporter of Wnt morphogens in developing tissues. Participates in the formation of endosomal carriers that direct WLS trafficking back to Golgi, away from lysosomal degradation . Appears to be implicated in intercellular communication by negatively regulating the release of exosomes . The flippase activity towards membrane lipids and its role in membrane asymmetry remains to be proved . Required for the maintenance of neurite morphology and synaptic transmission (By similarity).
Subcellular locations: Early endosome membrane, Recycling endosome membrane, Late endosome membrane, Golgi apparatus, Trans-Golgi network membrane, Cell membrane
Efficient exit from the endoplasmic reticulum does not require TMEM30A, nor TMEM30B . Transiently expressed in the cell membrane .