1.F.3.1.5
Miltosome-endosome contact site proteins, EHD1 (EHI105270; uniprot C4M131) of 507 aas and 0 TMSs, and ETMP1 (EHI175060; uniprot C4LZN1) of 256 aas and 1 or 2 TMSs at the C-terminus and possibly at about residue 80.  Membrane contact sites (MCSs) are key regulators of interorganellar communication and have been widely demonstrated between various organelles, but studies on MCSs involving mitochondrion-related organelles (MROs), present in some anaerobic parasitic protozoans, remain scarce. Entamoeba histolytica, the etiological agent of amoebiasis, possesses an MRO called the mitosome. This organelle is crucial for cellular differentiation and disease transmission, thereby contributing to the amoeba's parasitic lifestyle. The interaction between the Entamoeba-specific transmembrane mitosomal protein (ETMP1) and EH domain-containing protein (EHD1) showcases a mitosome-endosome contact site in E. histolytica (Santos et al. 2022). Despite their  divergent and reduced nature, MROs like mitosomes conserve mechanisms for interorganellar cross talk. Santos et al. 2022 suggested that lipid and ion transport, mitosome fission, and quality control are potential processes that are mediated by the ETMP1-EHD1-tethered mitosome-endosome contact site in E. histolytica.