title: Additional layers of gene regulatory complexity from recently discovered microRNA mechanisms.
abstract: In recent years microRNAs have become recognized as pervasive, versatile agents of gene regulation. Some widely embraced rules involving Watson-Crick hybridization of microRNAs with mRNAs have generated great interest as scientists envision potential RNA cargoes for gene therapy and other experimental systems. However, while researchers ardently seek simplifying principles, nature seems very uncooperative. This article reviews some small RNA mechanisms that potentially regulate genes and which are not covered by previous microRNAs characterizations. In addition, we report here results of fluorescence microscopy experiments to directly demonstrate nuclear import of small RNAs equal in length to typical mature microRNAs, implying that gene regulation at the locus of transcription might be possible.
authors.affiliation: Renaissance Computing Institute and Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, CB 360, Chapel Hill, NC 27599, USA. clark_jeffries@med.unc.edu
authors.forename: Clark D
authors.initials: CD
authors.lastname: Jeffries
authors.forename: Howard M
authors.initials: HM
authors.lastname: Fried
authors.forename: Diana O
authors.initials: DO
authors.lastname: Perkins
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009831:Olfactory Mucosa / Q000166:cytology / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: C527114:MIRN373 microRNA, human; D035683:MicroRNAs; D034741:RNA, Small Interfering
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