Ty1-copia group retrotransposons and the evolution of retroelements in several angiosperm plants: evidence of horizontal transmission.

The phylogenetic relationships among thirty-seven new Ty1-copia group retrotransposons in seven angiosperm plants were examined by reverse transcriptase and ribonuclease H sequence analysis. Distribution pattern of the retrotransposons of closely related plant species generally reflects a close phylogenetic relationship. In contrast, we found that several retrotransposon sequences from the same genome exhibited a high degree of divergence and had a relatively high degree of identity versus retrotransposon sequences from widely divergent species, including an ancestral phytopathogen fungus.

Polymorphism of a new Ty1-copia retrotransposon in durum wheat under salt and light stresses.

Long terminal repeat retrotransposons are the most abundant mobile elements in the plant genome and play an important role in the genome reorganization induced by environmental challenges. Their success depends on the ability of their promoters to respond to different signaling pathways that regulate plant adaptation to biotic and abiotic stresses. We have isolated a new Ty1-copia-like retrotransposon, named Ttd1a from the Triticum durum L.

Molecular authentication of three Italian melon accessions by ARMS-PCR and ITS1 (internal transcribed spacer 1) secondary structure prediction.

Genetic assessment was carried out on three Italian melon accessions by sequence and structural analysis of the internal transcribed spacer 1 (ITS1) from three populations belonging to two Cucumis melo L. varieties (madras and tendral). Alignment of the 18S-5.

Identification of a family of SINEs and LINEs in the Pipistrellus kuhli genome: a new structural and functional symbiotic relationship.

We initially describe a novel tRNA-derived SINE family, abundantly and randomly distributed in the genome of the bat Pipistrellus kuhli. We present evidence that the LINE retrotransposition machinery is recruited for the creation of a new chimerical retrotranscript constituted by the partial LINE reverse transcriptase ORF2, which is interrupted by the SINE15 retrotransposon. Structural homology between SINE15 and Homo sapiens helix 6 7SL RNA allows us to propose multiple genome partners for SINE retrotransposition, such as SRP proteins and LINE enzymatic machinery.

Recombinogenic activity of 10 chemical compounds in male germ cells of Drosophila melanogaster.

The Drosophila melanogaster male germ cells are sensitive to the recombinogenic activity of chemical compounds. In our experiments, we have employed four recessive markers located on the 2nd chromosome: dumpy (dp, 13.0), black (b, 48.

Molecular characterization of the first satellite DNA with CENP-B and CDEIII motifs in the bat Pipistrellus kuhli.

The centromere is an essential structure in the chromosomes of all eukariotes and is central to the mechanism that ensures proper segregation during mitosis and meiosis. The comparison of DNA sequence motifs, organization and kinetocore components from yeast to man is beginning to indicate that, although centromeres are highly variable DNA elements, a conserved pattern of sequence arrangement and function is emerging. We have identified and characterized the first satellite DNA (P.

A new pair of CR1-like LINE and tRNA-derived SINE elements in Podarcis sicula genome.

We have identified and characterized a new pair of LINE and SINE elements, called Lucy-1 CR1-like LINE and P.s.1/SINE, respectively, in Podarcis sicula genome.