Multiple Functions of Nuclear DNA Helicase Ⅱ （RNA Helicase A） in Nucleic Acid Metabolism

Secondary structures of nucleic acids play an importantrole in regulating their transactions as carriers of thegenetic information, including DNA replication, trans-cription, RNA processing, RNA transport, and translation.Resolving double-stranded (ds) DNA or RNA is usually anenergy-dependent process that can be accomplished byproteins termed DNA or RNA helicases, which are presentin all prokaryotic and eukaryotic organisms. Earlier attemptsto find mammalian helicases led to the detect…

Multiple functions of nuclear DNA helicase II (RNA helicase A) in nucleic acid metabolism

Nuclear DNA helicase II (NDH II), or RNA helicase A (RHA), was initially discovered in mammals by conventional protein purification methods. Molecular cloning identified apparent sequence ho- mologies between NDH II and a Drosophila protein named maleless (MLE), the latter being essential for the Drosophila X-chromosome dosage compensation. Increasing amounts of evidence suggest that NDH II is involved in multiple aspects of cellular and viral DNA and RNA metabolism. Moreover the functions of NDH II may have potential clinical implications related to viral infection, autoimmune diseases, or even tumorigenesis.