Component of the ERMES/MDM complex, which serves as a molecular tether to connect the endoplasmic reticulum and mitochondria. Components of this complex are involved in the control of mitochondrial shape and protein biogenesis and may function in phospholipid exchange. mdm10 is involved in the late assembly steps of the general translocase of the mitochondrial outer membrane (TOM complex). Functions in the tom40-specific route of the assembly of outer membrane beta-barrel proteins, including the association of tom40 with the receptor tom22 and small TOM proteins. Can associate with the SAM(core) complex as well as the mdm12-mmm1 complex, both involved in late steps of the major beta-barrel assembly pathway, that is responsible for biogenesis of all outer membrane beta-barrel proteins. May act as a switch that shuttles between both complexes and channels precursor proteins into the tom40-specific pathway. Plays a role in mitochondrial morphology and in the inheritance of mitochondria