Panel A: Growth phenotypes of yeast strains carrying indicated deletions and artificially tethered ERMES subunits, assessed by spot assay on SD plus FOA medium at 30 degrees Celsius. Panel B: Fluorescence micrographs of mitochondrial morphology from the strains described in Panel A; scale bars represent 2 micrometers. Panel C: Thin-layer chromatography (TLC) of total cellular phospholipids, resolving PC, PI, PS, PE, PA, and CL. Panel D: Quantitative analysis of cardiolipin (CL) levels expressed as a fraction of total major phospholipids. Data represent the mean plus minus SEM from three independent biological replicates. Panel E: Schematic overview of the Mmm1 truncation mutants utilized for the functional assays in Panel F. Panel F: Spot assay evaluating the growth of yeast strains expressing various Mmm1 truncations on SD plus FOA medium at 30 degrees Celsius.
SMP domain of Mmm1 is sufficient for rescue. (A) Spot assay of ERMES quadruple deletion yeast with and without the expression of artificially tethered ERMES members. (B) Representative images of mitochondria from the yeast in A. Scale bars are 2 μm. (C) Representative thin layer chromatogram of total cell phospholipid extracts. PC, phosphatidylcholine; PI, phosphatidylinositol; PS, phosphatidylserine; PE, phosphatidylethanolamine; PA, phosphatidic acid; CL, cardiolipin. (D) Quantification of CL levels relative to total major phospholipids. Values are means ± SE (n = 3 independent experiments). (E) Schematic of Mmm1 truncation constructs used in F. (F) Spot assay of mmm1Δmdm12Δmdm34Δmdm10Δ yeast expressing truncations of Mmm1. Source data are available for this figure: SourceData F4.