mRNA is synthesized on DNA template in 5′−3′ direction. Synthesis of mRNA exhibits several features that are synonymous with DNA replication. RNA synthesis requires accurate and efficient initiation, elongation proceeds in the 5′−3′ direction (i.e., the polymerase oves along the template strand of DNA in the 5′−3′ direction), and RNA synthesis requires distinct and accurate termination. Transcription exhibits several features that are distinct from replication.