FUS and sarcoma: OT film-like organelles were previously designed to locate at four different cellular membranes—plasma membrane (PM), Golgi membrane (GM), endoplasmic reticulum membrane (ERM) and outer mitochondrial membrane (OMM); these organelles were named PMP, GMP, ERMP, and OMMP, respectively (the suffix P indicates the presence of the protein FUS (fused in sarcoma) which has a tendency to phase separate at high concentrations)2.