Fig. 3

Mitochondria-localized bacterial TAs can functionally replace the TA of Fis1p. a The ElaB and YqjD TAs can replace the Fis1p TA in promotion of normal mitochondrial morphology. fis1∆ strain CDD741, expressing mitochondria-targeted GFP from plasmid pHS12, was transformed with empty vector pRS313 or plasmids expressing wild-type Fis1p (b239), Fis1(A144D)p (b244), or Fis1p with its own TA replaced by that of ElaB (b317), YqjD (b318), or YgiM (b316). Cells were examined by fluorescence microscopy. Scale bar, 5 μm. b Quantification of mitochondrial morphology of the transformants from (a) was performed blind to genotype. White bar represents cells with fully networked mitochondria, grey bar represents cells with mitochondria not fully networked, but networked to a greater extent than wild-type cells, and black bar represents cells with normal mitochondrial morphology. Quantification was repeated three times (n > 200 per genotype), and a representative experiment is shown. c Genetic assessment of Fis1p variant functionality. Strain CDD688 was transformed with the plasmids used in (a) and proliferation was assessed without selection against Fis1p activity (YPALac medium for 2 d) or following counter-selection for cells carrying functional Fis1p (SLac-His + CHX medium for 4 d)