Highly heterogeneous families of Ty1/copia retrotransposons in the Lycopersicon chilense genome.
We have used the degenerated oligonucleotide primers-PCR (DOP-PCR) technique to determine the presence of Ty1/copia-related retrotransposons in the wild species of tomato, Lycopersicon chilense. Using degenerated oligonucleotides corresponding to highly conserved domains in the Ty1/copia retrotransposons, fragments of roughly 300 bp were obtained by PCR amplification. These were cloned in a plasmid vector and the nucleotide sequence determined for 20 clones, 19 of which showed sequence homology to retrotransposon-related sequences. Comparison of the deduced amino-acid sequence of these clones with those reported for other retrotransposons has allowed their classification into four distinct families: TLC1-TLC4. The level of amino-acid sequence similarity between these elements extends from 66.7% (between TLC1 and TLC2) to 42.6% (between TLC2 and TLC3). Altogether, the four families comprise about 0.17% of the L. chilense genome. RT-PCR analysis shows that the four TLC families are transcriptionally active, suggesting a mechanism for the generation of the observed diversity between the L. chilense retrotransposons.
Yañez
M
M
Instituto de Biología Vegetal y Biotecnología, Universidad de Talca, Casilla, 747, Talca, Chile.
Verdugo
I
I
Rodríguez
M
M
Prat
S
S
Ruiz-Lara
S
S
D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D018745:Genome, Plant; D018551:Solanum lycopersicum / Q000235:genetics*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics; D016133:Polymerase Chain Reaction; D018626:Retroelements; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; D018744:DNA, Plant; D010940:Plant Proteins; D018626:Retroelements