title: Evidence that microRNA precursors, unlike other non-coding RNAs, have lower folding free energies than random sequences.
abstract: BACKGROUND
  Most non-coding RNAs are characterized by a specific secondary and tertiary structure that determines their function. Here, we investigate the folding energy of the secondary structure of non-coding RNA sequences, such as microRNA precursors, transfer RNAs and ribosomal RNAs in several eukaryotic taxa. Statistical biases are assessed by a randomization test, in which the predicted minimum free energy of folding is compared with values obtained for structures inferred from randomly shuffling the original sequences.
  
  
  RESULTS
  In contrast with transfer RNAs and ribosomal RNAs, the majority of the microRNA sequences clearly exhibit a folding free energy that is considerably lower than that for shuffled sequences, indicating a high tendency in the sequence towards a stable secondary structure. A possible usage of this statistical test in the framework of the detection of genuine miRNA sequences is discussed.
authors.affiliation: Department of Plant Systems Biology, Flanders Interuniversity Institute for Biotechnology (VIB), Ghent University, Technologiepark 927, B-9052 Ghent, Belgium.
authors.forename: Eric
authors.initials: E
authors.lastname: Bonnet
authors.forename: Jan
authors.initials: J
authors.lastname: Wuyts
authors.forename: Pierre
authors.initials: P
authors.lastname: Rouzé
authors.forename: Yves
authors.initials: Y
authors.lastname: Van de Peer
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics*; D003198:Computer Simulation; D004331:Drosophila melanogaster / Q000235:genetics*; D004735:Energy Transfer; D006801:Humans; D035683:MicroRNAs / Q000737:chemistry*; D008956:Models, Chemical; D015233:Models, Statistical; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D016415:Sequence Alignment / Q000379:methods*; D017423:Sequence Analysis, RNA / Q000379:methods*; D013329:Structure-Activity Relationship; D013816:Thermodynamics
chemical_list: D035683:MicroRNAs