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F Quétier

Publications and source records attributed to F Quétier.

5 recordsLinked to original sources

An internal part of the chloroplast atpA gene sequence is present in the mitochondrial genome of Triticum aestivum: molecular organisation and evolutionary aspects.

An internal part of the chloroplast atpA gene has been identified in the mitochondrial DNA of Triticum aestivum. It is located near the 18S-5S ribosomal genes and partially contained within a repeated sequence. Comparison of the transferred sequence with the original ct sequence reveals several nucleotide changes and shows that neither 5' nor 3' ends are present in the mt genome. No transcript of this region could be detected by Northern analysis. This sequence is present in mitochondrial genomes of other tetraploid and diploid species of Triticum, also in the vicinity of the 18S-5S ribosomal genes, suggesting a unique transfer event. The date of this event is discussed.

Adenosine Triphosphatases

Nucleotide sequence and determination of the extremities of the 26S ribosomal RNA gene in wheat mitochondria: evidence for sequence rearrangements in the ribosomal genes of higher plants.

The nucleotide sequence of the wheat mitochondrial 26S ribosomal RNA gene and flanking regions was determined and compared with mitochondrial 26S rRNA genes from maize and Oenothera. All three genes exhibit a high degree of homology except within two variable regions. When the plant mitochondrial 26S rRNA genes are compared with Escherichia coli 23S rRNA and chloroplast 23S and 4.5S rRNA genes, a third variable region is apparent close to the 3' end of the gene. The 5' and 3' ends of the wheat mitochondrial gene were determined by S1 nuclease mapping. Computer analysis of the wheat mitochondrial gene revealed several small sequences present either in the 5' region of the 26S rRNA gene or in the 18S rRNA gene.

Base Sequence

Characterization of two minicircular plasmid-like DNAs isolated from date-palm mitochondria.

We report here the identification and characterization of two minicircular plasmid-like DNAs isolated from mitochondria of a moroccan date-palm variety. Both molecules were cloned and used as probes in Southern analyses of mitochondrial and total-cellular DNA. Evidence was obtained that these plasmid-like DNAs cross-hybridized but did not show any homology to nuclear, chloroplastic, or main mitochondrial genomes. Sequence analysis revealed that both minicircles, 1,346- and 1,160-bp long, share several stretches of homology, the most important consisting of three identical clusters of lengths 42, 47 and 38 bp. In contrast, no major homology was observed with the other higher-plant plasmid-like DNAs reported so far. Sequence analysis also revealed the presence, in the same strand of one of the minicircles, of two open reading frames potentially encoding proteins 89 and 86 amino acids in length. Interestingly, Northern analyses, using single strands of each minicircle as probes, showed the presence of two transcripts hybridizing only with the strand bearing these two open reading frames. However, computer-assisted comparison of the predicted polypeptide sequences with a protein-sequence library failed to detect any significant homology to known sequences.

Base Sequence