Mitochondrial-derived compartments contain sets of paired membranes. (A–I) 2D cross sections and 3D models derived from 200-nm cell sections of yeast cells treated with 200 nM Rap. Scale bar = 200 nm. See associated Videos 2, 3, and 4. (A) Tomograph of a small, putative MDC bound by a single double-membrane from a haploid yeast cell expressing Tom70-yEGFP and Tim50-mCherry treated with 200 nM Rap. Yellow arrows: mitochondria, white arrow: MDC. (B) Model overlay of the tomograph shown in A. (C) 3D model of small, putative MDCs bound by a single double-membrane (labeled green). Mitochondria: purple, ER: yellow. See associated Video 2. (D) Tomograph of a larger, putative MDC bound by four membrane bilayers from a haploid yeast cell expressing Tom70-yEGFP and Tim50-mCherry treated with 200 nM Rap. Yellow arrow: mitochondria, white arrow: MDC. (E) Model overlay of the tomograph shown in D. (F) 3D model of the larger, putative MDC bound by two closely apposed paired membranes. The limiting membrane of the outer doublet membrane is labeled green, while the internal doublet membrane is labeled cyan. Mitochondria: purple, ER: yellow. See associated Video 3. (G) Tomograph of a larger, putative MDC bound by four membrane bilayers from the wild-type BY4741 yeast strain. Yellow arrow: mitochondria, white arrow: MDC. (H) Model overlay of the tomograph shown in D. (I) 3D model of the larger, putative MDC bound by two closely apposed paired membranes. The limiting membrane of the outer doublet membrane is labeled green, while the internal doublet membrane is labeled cyan. Mitochondria: purple, ER: yellow. See associated Video 4.