I-RNA polymerase iyi-enzyme edlala indima ebalulekile enqubweni yokulotshwa, okuyinqubo lapho i-DNA isetshenziswa khona ukuze kuhlanganiswe ama-molecule e-RNA. I-RNA polymerase isebenza "ngokufunda" umucu wesifanekiso se-DNA futhi uyisebenzise ukwakha i-molecule ye-RNA ehambisanayo. Kunezinhlobo eziningana ze-RNA polymerase, ngayinye enesibopho sokuhlanganisa izinhlobo ezahlukene zama-molecule e-RNA. Ngokuvamile, i-RNA polymerase iwuhlobo lwe-enzyme ekhuthaza ukwakheka kwama-molecule e-RNA kusuka kuma-nucleotide precursors.