title: The mitochondrial genome encodes abundant small noncoding RNAs.
abstract: Small noncoding RNAs identified thus far are all encoded by the nuclear genome. Here, we report that the murine and human mitochondrial genomes encode thousands of small noncoding RNAs, which are predominantly derived from the sense transcripts of the mitochondrial genes (host genes), and we termed these small RNAs mitochondrial genome-encoded small RNAs (mitosRNAs). DICER inactivation affected, but did not completely abolish mitosRNA production. MitosRNAs appear to be products of currently unidentified mitochondrial ribonucleases. Overexpression of mitosRNAs enhanced expression levels of their host genes in vitro, and dysregulated mitosRNA expression was generally associated with aberrant mitochondrial gene expression in vivo. Our data demonstrate that in addition to 37 known mitochondrial genes, the mammalian mitochondrial genome also encodes abundant mitosRNAs, which may play an important regulatory role in the control of mitochondrial gene expression in the cell.
authors.affiliation: Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557, USA.
authors.forename: Seungil
authors.initials: S
authors.lastname: Ro
authors.forename: Hsiu-Yen
authors.initials: HY
authors.lastname: Ma
authors.forename: Chanjae
authors.initials: C
authors.lastname: Park
authors.forename: Nicole
authors.initials: N
authors.lastname: Ortogero
authors.forename: Rui
authors.initials: R
authors.lastname: Song
authors.forename: Grant W
authors.initials: GW
authors.lastname: Hennig
authors.forename: Huili
authors.initials: H
authors.lastname: Zheng
authors.forename: Yung-Ming
authors.initials: YM
authors.lastname: Lin
authors.forename: Loredana
authors.initials: L
authors.lastname: Moro
authors.forename: Jer-Tsong
authors.initials: JT
authors.lastname: Hsieh
authors.forename: Wei
authors.initials: W
authors.lastname: Yan
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000235:genetics; D002874:Chromosome Mapping; D053487:DEAD-box RNA Helicases; D054629:Genome, Mitochondrial / Q000235:genetics*; D006801:Humans; D051379:Mice; D008928:Mitochondria / Q000235:genetics*; D058727:RNA, Small Untranslated / Q000235:genetics*; D043244:Ribonuclease III / Q000378:metabolism
chemical_list: D058727:RNA, Small Untranslated; C408087:DICER1 protein, human; D043244:Ribonuclease III; D053487:DEAD-box RNA Helicases