synaptotagmin-like mitochondrial-lipid-binding protein (SMP) domain found in mitochondrial distribution and morphology protein 12 (Mdm12) and similar proteins
Mitochondrial distribution and morphology protein 12 (Mdm12), also called mitochondrial inheritance component Mdm12, acts as a component of the endoplasmic reticulum-mitochondria encounter structure (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 function in nonvesicular lipid trafficking between the endoplasmic reticulum (ER) and mitochondria. Mdm12 is required for the interaction of the ER-resident membrane protein 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. The Mdm10-Mdm12-Mmm1 subcomplex further acts in the TOM40-specific pathway after the action of the Mdm12-Mmm1 complex. This model corresponds to the SMP domain of Mdm12, which adopts a head-to-head and tail-to-tail dimer configuration rather than existing solely as a monomer. It may be implicated in lipid transport.
Jiyao W et al.(2023). "The conserved domain database in 2023.",