Enables protein heterodimerization activity. Contributes to trans-hexaprenyltranstransferase activity and trans-octaprenyltranstransferase activity. Involved in isoprenoid biosynthetic process and ubiquinone biosynthetic process. Located in mitochondrion. Part of transferase complex. Human ortholog(s) of this gene implicated in primary coenzyme Q10 deficiency 2. Orthologous to human PDSS1 (decaprenyl diphosphate synthase subunit 1). [provided by Alliance of Genome Resources, Apr 2022]