Thomas Sollner (University of Munich): "The complex organization of eucaryotic cells into various membrane-bound compartments (organelles) requires a very specific targeting of newly synthesized proteins to their final destinations. All noncytosolic proteins are synthesized as signal-carrying precursors, which are decoded by receptor-like structures on the surface of the organelles. In the cited article, we describe the identification of MOM19, a 19-kilodalton protein. This is the first mitochondrial outer-membrane protein fulfilling the criteria proposed for a receptor of mitochondrial precursor proteins. MOM19 seems to function as a `master receptor' for most--but not all--precursors.
"The interaction of precursor proteins with MOM19 is the first step of the complex pathway of protein import into mitochondria. The identification of MOM19 now provides the basis for determining the critical regions and structures of the receptor and the precursor proteins involved in high-affinity binding. In general, the identification of this receptor, and its biochemical and molecular ...
