title: Many novel mammalian microRNA candidates identified by extensive cloning and RAKE analysis.
abstract: MicroRNAs are 20- to 23-nucleotide RNA molecules that can regulate gene expression. Currently > 400 microRNAs have been experimentally identified in mammalian genomes, whereas estimates go up to 1000 and beyond. Here we show that many more mammalian microRNAs exist. We discovered novel microRNA candidates using two approaches: testing of computationally predicted microRNAs by a modified microarray-based detection system, and cloning and sequencing of large numbers of small RNAs from different human and mouse tissues. Together these efforts experimentally identified 348 novel mouse and 81 novel human microRNA candidate genes. Most novel microRNAs candidates are not conserved beyond mammals, and ~10% are taxon-specific. Our analyses indicate that the entire microRNA repertoire is not remotely exhausted.
authors.affiliation: Hubrecht Laboratory, 3584 CT Utrecht, The Netherlands.
authors.forename: Eugene
authors.initials: E
authors.lastname: Berezikov
authors.forename: Geert
authors.initials: G
authors.lastname: van Tetering
authors.forename: Mark
authors.initials: M
authors.lastname: Verheul
authors.forename: Jose
authors.initials: J
authors.lastname: van de Belt
authors.forename: Linda
authors.initials: L
authors.lastname: van Laake
authors.forename: Joost
authors.initials: J
authors.lastname: Vos
authors.forename: Robert
authors.initials: R
authors.lastname: Verloop
authors.forename: Marc
authors.initials: M
authors.lastname: van de Wetering
authors.forename: Victor
authors.initials: V
authors.lastname: Guryev
authors.forename: Shuji
authors.initials: S
authors.lastname: Takada
authors.forename: Anton Jan
authors.initials: AJ
authors.lastname: van Zonneveld
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mano
authors.forename: Ronald
authors.initials: R
authors.lastname: Plasterk
authors.forename: Edwin
authors.initials: E
authors.lastname: Cuppen
mesh_terms: D000818:Animals; D020029:Base Pairing; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D006801:Humans; D051379:Mice / Q000235:genetics*; D035683:MicroRNAs / Q000235:genetics*; D046228:Microarray Analysis / Q000379:methods*; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA
chemical_list: D035683:MicroRNAs