The TULIP complex is a major mediator of lipid sensing and transport in eukaryotes (Alva and Lupas 2016). Component of the ERMES/MDM complex, which serves as a molecular tether to connect the endoplasmic reticulum and mitochondria include MMM1, MMM2 (MDM34), MDM10 and MDM12. This complex is involved in the control of mitochondrial shape and protein biogenesis and may function in phospholipid exchange. MDM34 (MMM2) is required for the interaction of the ER-resident membrane protein MMM1 and the outer mitochondrial membrane-resident beta-barrel protein MDM10. MDM12 is required for the interaction of MMM1 and the outer mitochondrial membrane-resident beta-barrel protein MDM10. The MDM12-MMM1 subcomplex functions in the major beta-barrel assembly pathway that is responsible for biogenesis of all mitochondrial outer membrane beta-barrel proteins, and acts in a late step after the SAM complex (TC# 1.B.33). The MDM10-MDM12-MMM1 subcomplex further acts in the TOM40-specific pathway (TC# 1.B.8) after the action of the MDM12-MMM1 complex (Meisinger et al. 2007).  Discrete sites of close apposition between ER and mitochondria may facilitate interorganelle calcium and phospholipid exchange (Kornmann et al. 2009).  See family description for more details and additional references.