Fig. 1: Phylogenetic distribution of mt-Ca²⁺ uniporter protein families.

The phylogenetic distribution of MCU (red), MICU (green), and EMRE (gray) homologs across 1156 eukaryotic genomes is shown on the NCBI taxonomy tree. Viridiplantae and Rhodophyta (red algae) have been grouped together as Archaeplastida, and alveolates, stramenopiles (Str/es), and rhizarians as the SAR clade. In all cases where data from various strains of a species are present with the same pattern, these have all been collapsed to the species level, resulting in 969 terminal nodes shown. The mt-Ca²⁺ uniporter complex has been completely lost in Apicomplexa within Alveolates, Rhizaria (5 genomes), red algae (3 genomes), Cryptophytes (3 genomes), Haptophytes (1 genome), and the Entamoeba clade within Amoebozoa. Within fungi (in purple), all major clades that have completely lost MCU homologs are indicated with a darker purple color, namely Onygenales, Saccharomycetales, Pucciniomycotina, Mucoromycotina (Mucor/a), and Microsporidia (Micro/a). The only three early diverging fungal species (A. macrogynus-Am, C. anguillae-Ca, S. punctatus-Sp) that encode also MICU and EMRE are highlighted with a red arrowhead. The NCBI taxonomy and the presence/absence profile were visualized using the ETE toolkit⁴¹. For a version of the profile, which includes the species names, see Supplementary Fig. 1.