Plays a role in the regulation of the mitochondrial ribosome assembly and of translational activity. Displays mitochondrial GTPase activity. Associates with the mitochondrial ribosome large subunit; the association occurs in a GTP-dependent manner (PubMed:23396448). Belongs to the TRAFAC class YlqF/YawG GTPase family. MTG1 subfamily. Extended N-terminus. Truncated N-terminus.