title: AtnMat2, a nuclear-encoded maturase required for splicing of group-II introns in Arabidopsis mitochondria.
abstract: Mitochondria (mt) in plants house about 20 group-II introns, which lie within protein-coding genes required in both organellar genome expression and respiration activities. While in nonplant systems the splicing of group-II introns is mediated by proteins encoded within the introns themselves (known as "maturases"), only a single maturase ORF (matR) has retained in the mitochondrial genomes in plants; however, its putative role(s) in the splicing of organellar introns is yet to be established. Clues to other proteins are scarce, but these are likely encoded within the nucleus as there are no obvious candidates among the remaining ORFs within the mtDNA. Intriguingly, higher plants genomes contain four maturase-related genes, which exist in the nucleus as self-standing ORFs, out of the context of their evolutionary-related group-II introns "hosts." These are all predicted to reside within mitochondria and may therefore act "in-trans" in the splicing of organellar-encoded introns. Here, we analyzed the intracellular locations of the four nuclear-encoded maturases in Arabidopsis and established the roles of one of these genes, At5g46920 (AtnMat2), in the splicing of several mitochondrial introns, including the single intron within cox2, nad1 intron2, and nad7 intron2.
authors: Volcani Center, Institute of Plant Sciences, Agricultural Research Organization, Bet Dagan 50250, Israel.
authors: Ido
authors: I
authors: Keren
authors: Ayenachew
authors: A
authors: Bezawork-Geleta
authors: Max
authors: M
authors: Kolton
authors: Inbar
authors: I
authors: Maayan
authors: Eduard
authors: E
authors: Belausov
authors: Maggie
authors: M
authors: Levy
authors: Anahit
authors: A
authors: Mett
authors: David
authors: D
authors: Gidoni
authors: Felix
authors: F
authors: Shaya
authors: Oren
authors: O
authors: Ostersetzer-Biran
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000201:enzymology; D042541:Intracellular Space / Q000201:enzymology; D007438:Introns; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D010641:Phenotype; D012326:RNA Splicing; D018749:RNA, Plant / Q000235:genetics*; D012194:RNA-Directed DNA Polymerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D029681:Arabidopsis Proteins; D018749:RNA, Plant; D012194:RNA-Directed DNA Polymerase; C545659:nMat2 protein, Arabidopsis