The wheat mitochondrial gene for subunit I of the NADH dehydrogenase complex: A trans-splicing model for this gene-in-pieces

• Published in: Cell Vol. 65; no. 3; pp. 465 - 472
• Main Authors: Chapdelaine, Yvan, Bonen, Linda
• Format: Journal Article
• Language: English
• Published: Cambridge, MA Elsevier Inc 03.05.1991; Cell Press
• Subjects: Amino Acid Sequence; Base Sequence; Biological and medical sciences; Codon; DNA, Mitochondrial - genetics; Exons; Fundamental and applied biological sciences. Psychology; genes; Genes. Genome; Introns; Mitochondria - enzymology; Models, Genetic; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; mRNA; NAD(P)H Dehydrogenase (Quinone); Nucleic Acid Conformation; Quinone Reductases - genetics; Repetitive Sequences, Nucleic Acid; RNA Splicing; splicing; Transcription, Genetic; Triticum - enzymology; Triticum - genetics; Triticum aestivum; Mitochondria; Nucleotide sequence; Enzyme; NADH dehydrogenase; Gene organization; Mitochondrial DNA; Gene expression; Wheat
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/0092-8674(91)90464-A

The nadl gene encoding subunit I of the respiratory chain NADH dehydrogenase is fragmented into five unique-copy coding segments that are scattered over at least 40 kb and interspersed with other genes in the wheat mitochondrial genome. The nad1 segments are flanked by sequences with group II intron features, and transcript analysis demonstrates the presence of correctly spliced mRNAs. RNA editing occurs at sites asymmetrically distributed along the wheat nad1 coding region, and the initiation codon is created by RNA editing. The unusual organization of the wheat nad1 gene is attributed to mitochondrial DNA rearrangements within introns, and a trans-splicing model involving secondary structural interactions between group II-like intron pieces is proposed for its expression.