title: Import routes and nuclear functions of Argonaute and other small RNA-silencing proteins.
abstract: Small RNAs are important regulators of gene expression in many different organisms. Nuclear and cytoplasmic biogenesis enzymes generate functional small RNAs from double-stranded (ds) or single-stranded (ss) RNA precursors, and mature small RNAs are loaded into Argonaute proteins. In the cytoplasm, small RNAs guide Argonaute proteins to complementary RNAs leading to cleavage of these targets, translational silencing, or mRNA decay. In the nucleus Argonaute proteins engage in transcriptional silencing processes such as epigenetic silencing of repetitive elements at the chromatin level. During the past few years many novel functions of small RNA-guided gene silencing proteins in the nucleus have been reported. However, their specific import routes are largely unknown. In this review we summarize the current knowledge on nuclear transport routes that Argonaute and other RNA-silencing proteins take to carry out their various functions in the nucleus.
authors.affiliation: Biochemistry Center Regensburg (BZR), Laboratory for RNA Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schraivogel
authors.affiliation: Biochemistry Center Regensburg (BZR), Laboratory for RNA Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany. Electronic address: gunter.meister@vkl.uni-regensburg.de.
authors.forename: Gunter
authors.initials: G
authors.lastname: Meister
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D020868:Gene Silencing; D006801:Humans; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D060565:Argonaute Proteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins
keywords: Argonaute proteins; RNAe; gene silencing; microRNAs; nuclear RNAi; siRNAs