Every living cell transcribes DNA into RNA. This process begins when an enzyme called RNA polymerase (RNAP) clamps onto DNA. Within a few hundred milliseconds, the DNA double helix unwinds to form a node known as the transcription bubble, so that one exposed DNA strand can be copied into a complementary RNA strand. Every living cell transcribes DNA into RNA. This process begins when an enzyme called RNA polymerase (RNAP) clamps onto DNA. Within a few hundred milliseconds, the DNA double helix unwinds to form a node known as the transcription bubble, so that one exposed DNA strand can be copied into a complementary RNA strand. Biotechnology Molecular & Computational biology Phys.org – latest science and technology news stories