Mdv1 interacts with assembled Dnm1 to promote mitochondrial division

The dynamin-related GTPase, Dnm1, self-assembles into punctate structures that are targeted to the outer mitochondrial membrane where they mediate mitochondrial division. Post-targeting, Dnm1-dependent division is controlled by the actions of the WD repeat protein, Mdv1, and the mitochondrial tetratricopeptide repeat-like outer membrane protein, Fis1. Our previous studies suggest a model where at this step Mdv1 functions as an adaptor linking Fis1 with Dnm1. To gain insight into the exact role of the Fis1 center dot Mdv1 center dot Dnm1 complex in mitochondrial division, we performed a structure-function analysis of the Mdv1 adaptor. Our analysis suggests that dynamic interactions between Mdv1 and Dnm1 play a key role in division by regulating Dnm1 self-assembly.