Fig. 8

Structural model of ERMES complex in T. vaginalis. A Model of the ERMES Tvmm1a-TvMdm12-TvMmm2b-Porin2 heterotetramer as predicted by ColabFold. Predicted domains are colored according to the pLDDT score of confidence. Arrows pointed at C-(carboxy) and N- (amino) terminus of each subunit. B Visualization of the hydrophobic amino acid residues in the inner surface of the ERMES conduit. The ERMES complex is shown as mesh and each amino acid is colored by its hydrophobicity score as defined by the color_h.py script. C Models of possible arrangements of ERMES components tethering ER and mitochondrial (hydrogenosomal) membranes. Model I. The shuttle model, Mmm1 and Mmm2 flexible linkers allow the complex movement between membranes [2]. Model II. In the two-tunnel model, Mmm1 is dimerized and each Mmm1 subunit interacts with a different partner (Mdm12, Mmm2) [32]. Model III. Mmm1 is dimerized and each subunit forms a continuous conduit with Mdm12-Mmm2 that is anchored to mitochondrial/hydrogenosomal membrane via Mdm10/Porin2, respectively ( [3], this work). Model IV. A single continuous conduit was reconstructed from light and electron cryo-microscopy [33]