title: Expression of a novel non-coding mitochondrial RNA in human proliferating cells.
abstract: Previously, we reported the presence in mouse cells of a mitochondrial RNA which contains an inverted repeat (IR) of 121 nucleotides (nt) covalently linked to the 5' end of the mitochondrial 16S RNA (16S mtrRNA). Here, we report the structure of an equivalent transcript of 2374 nt which is over-expressed in human proliferating cells but not in resting cells. The transcript contains a hairpin structure comprising an IR of 815 nt linked to the 5' end of the 16S mtrRNA and forming a long double-stranded structure or stem and a loop of 40 nt. The stem is resistant to RNase A and can be detected and isolated after digestion with the enzyme. This novel transcript is a non-coding RNA (ncRNA) and several evidences suggest that the transcript is synthesized in mitochondria. The expression of this transcript can be induced in resting lymphocytes stimulated with phytohaemagglutinin (PHA). Moreover, aphidicolin treatment of DU145 cells reversibly blocks proliferation and expression of the transcript. If the drug is removed, the cells re-assume proliferation and over-express the ncmtRNA. These results suggest that the expression of the ncmtRNA correlates with the replicative state of the cell and it may play a role in cell proliferation.
authors.affiliation: Bios Chile Ingeniería Genética S.A.
authors.forename: Jaime
authors.initials: J
authors.lastname: Villegas
authors.forename: Veronica
authors.initials: V
authors.lastname: Burzio
authors.forename: Claudio
authors.initials: C
authors.lastname: Villota
authors.forename: Eduardo
authors.initials: E
authors.lastname: Landerer
authors.forename: Ronny
authors.initials: R
authors.lastname: Martinez
authors.forename: Marcela
authors.initials: M
authors.lastname: Santander
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Martinez
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Pinto
authors.forename: María I
authors.initials: MI
authors.lastname: Vera
authors.forename: Enrique
authors.initials: E
authors.lastname: Boccardo
authors.forename: Luisa L
authors.initials: LL
authors.lastname: Villa
authors.forename: Luis O
authors.initials: LO
authors.lastname: Burzio
mesh_terms: D049109:Cell Proliferation; D015870:Gene Expression; D006801:Humans; D008928:Mitochondria / Q000235:genetics; D012313:RNA / Q000737:chemistry / Q000378:metabolism*; D000077278:RNA, Mitochondrial; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D022661:RNA, Untranslated / Q000737:chemistry / Q000378:metabolism*; D012091:Repetitive Sequences, Nucleic Acid; D012259:Ribonuclease, Pancreatic / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D000077278:RNA, Mitochondrial; D012336:RNA, Ribosomal, 16S; D022661:RNA, Untranslated; D012313:RNA; D012259:Ribonuclease, Pancreatic