Involvement of DNA ligase III and ribonuclease H1 in mitochondrial DNA replication in cultured human cells

► The data suggest that DNA ligase III is the replicative DNA ligase in human mitochondria. ► RNase H1 is indispensable for Okazaki fragment processing in human mtDNA replication. ► On the other hand, knockdown of neither DNA2 nor FEN1 affected mtDNA replication. ► Mitochondria utilise distinct proteins for Okazaki fragment maturation from nucleus.