Component of the CCZ1-MON1 RAB7A guanine exchange factor (GEF). Acts as a positive regulator of CCZ1-MON1A/B function necessary for endosomal/autophagic flux and efficient RAB7A localization (PubMed:29038162). . This is the function of ENSG00000141452 (RMC1, regulator of MON1-CCZ1).