Cis- and trans-splicing and RNA editing are required for the expression of nad2 in wheat mitochondria.
In wheat mitochondria, the gene coding for subunit 2 of the NADH-ubiquinone oxidoreductase (nad2) is divided into five exons located in two distant genomic regions. The first two exons of the gene, a and b, lie 22 kb downstream of exons c, d, and e, on the same DNA strand. All introns of nad2 are group II introns. A trans-splicing event is required to join exons b and c. It involves base pairing of the two precursor RNAs in the stem of domain IV of the intron. A gene coding for tRNA(Tyr) is located upstream of exon c. In addition to splicing processes, mRNA editing is also required for the correct expression of nad2. The mature mRNA is edited at 36 positions, distributed over its five exons, resulting in 28 codon modifications. Editing increases protein hydrophobicity and conservation.
Institut de Biologie Moléculaire des Plantes du CNRS, Université Louis Pasteur, Strasbourg, France.
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V
Morawala-Patell
J M
JM
Gualberto
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Lamattina
J M
JM
Grienenberger
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G
Bonnard
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D042967:Electron Transport Complex I; D005091:Exons / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D007438:Introns / Q000235:genetics; D008928:Mitochondria / Q000235:genetics*; D008969:Molecular Sequence Data; D009247:NADH, NADPH Oxidoreductases / Q000235:genetics*; D009690:Nucleic Acid Conformation; D017393:RNA Editing / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics*; D018749:RNA, Plant / Q000737:chemistry / Q000378:metabolism; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014908:Triticum / Q000235:genetics*
D018749:RNA, Plant; D009247:NADH, NADPH Oxidoreductases; D042967:Electron Transport Complex I