Figure 1: Identification of ATOM complex subunits.

(a) Venn diagram showing the overlap of the T. brucei OM proteome (green)¹⁹ with proteins identified in IPs using mitochondria isolated from cells expressing HA-tagged ATOM40. Elution was either done under denaturing conditions (red) (Supplementary Data 1) or under native condition with subsequent size selection by BN–PAGE (blue) (Supplementary Data 2). (b) Immunofluorescence microscopy of c-Myc-tagged candidate proteins (red) and ATOM40 (green). Merge pictures include staining with 4′,6-diamidino-2-phenylindole (DAPI) to visualize nuclear and mitochondrial DNA (blue). Bar, 10 μm. (c) Immunoblot analysis of c-Myc-tagged candidate proteins in whole cells (T), crude mitochondrial (P) and cytosolic fractions (S). EF1a, mtHSP70 and VDAC served as cytosolic or mitochondrial marker proteins, respectively. (d) Relative abundance of the putative ATOM complex subunits (red) estimated by normalized intensity values of 1,056 proteins identified by mass spectrometry of gradient-purified mitochondria¹⁹. (e) Relative abundance differences between insect stage (PCF) and bloodstream form (BSF) T. brucei of putative ATOM complex subunits, subunits of the cytochrome c oxidase (COXs) and terminal alternative oxidase (TAO)²¹ (see also Supplementary Fig. 1).