Mitochondrial inheritance defects in myo2 mutants are rescued by a mitochondria-specific Myo2 variant. (A) Domain structure of WT and mutant Myo2 proteins. The numbers specify amino acid residues. Mutations are indicated by asterisks. (B) A schematic drawing of expected binding of Myo2 variants to mitochondria. (left) The WT Myo2 is thought to bind to a yet unidentified receptor (X) on the mitochondrial surface. (middle) Mutations in the Myo2 cargo binding domain (asterisks) are expected to weaken the interaction of Myo2 with mitochondria. (right) Myo2-Fis1 is directly inserted into the mitochondrial outer membrane through the Fis1 tail anchor and is expected to rescue cargo binding-defective myo2 mutants. (C) Cells expressing mtGFP were grown in synthetic dextrose minimal medium to the logarithmic growth phase, incubated for 3 h at the indicated temperature, and analyzed by fluorescence microscopy at ambient temperature. (left) GFP fluorescence. (right) Differential interference contrast (DIC) image. Bar, 5 µm. (D) Cells were grown and analyzed as in C, and buds devoid of mitochondria were quantified in cells carrying large buds. Quantifications are mean values from three independent experiments (n = 100), and error bars indicate standard deviations.