Male-sterility induction in transgenic tobacco plants with an unedited atp9 mitochondrial gene from wheat.
Cytoplasmic male sterility in plants is associated with mitochondrial dysfunction. We have proposed that a nuclear-encoded chimeric peptide formed by mitochondrial sequences when imported into the mitochondria may impair organelle function and induce male sterility in plants. A model developed to test this hypothesis is reported here. Assuming that the editing process in higher plant mitochondria reflects a requirement for producing active proteins, we have used edited and unedited coding sequences of wheat ATP synthase subunit 9 (atp9) fused to the coding sequence of a yeast coxIV transit peptide. Transgenic plants containing unedited atp9 exhibited either fertile, semifertile, or male-sterile phenotypes; controls containing edited atp9 or only the selectable marker gave fertile plants. Pollen fertility ranged from 31% to 75% in fertile plants, 10% to 20% in semifertile plants, and < 2% in male-sterile plants. Genetic and molecular data showed that the chimeric plasmid containing the transgene is inherited as a Mendelian trait. The transgenic protein is imported into the mitochondria. The production and frequency of semifertile or male-sterile transgenic plants conform to the proposed hypothesis.
Hernould
M
M
Université de Bordeaux II, Laboratoire de Biologie Cellulaire, Talence, France.
Suharsono
S
S
Litvak
S
S
Araya
A
A
Mouras
A
A
D000595:Amino Acid Sequence; D001483:Base Sequence; D003433:Crosses, Genetic; D003576:Electron Transport Complex IV / Q000235:genetics; D005298:Fertility; D007246:Infertility; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010641:Phenotype; D017853:Phosphotransferases (Alcohol Group Acceptor); D030821:Plants, Genetically Modified / Q000502:physiology*; D010947:Plants, Toxic; D016133:Polymerase Chain Reaction / Q000379:methods; D006180:Proton-Translocating ATPases / Q000235:genetics*; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014026:Nicotiana / Q000235:genetics* / Q000502:physiology; D014908:Triticum / Q000201:enzymology / Q000235:genetics* / Q000502:physiology
D009838:Oligodeoxyribonucleotides; D012313:RNA; D003576:Electron Transport Complex IV; D017853:Phosphotransferases (Alcohol Group Acceptor); C063242:hygromycin-B kinase; D006180:Proton-Translocating ATPases