[Tv1--a new family of Drosophila virilis retrotransposons].
A new method for isolation and cloning of functionally active retrotransposons was proposed and tested. The method is based on the hypothesis about the universal character of retrotransposition through reverse transcription. A new retrotransposon family (Tvl) was coned from the Drosophila virilis genome. A full-length Tvl copy was 7 kb. The cell line under consideration contained 500-1000 Tvl copies per cell, i.e., it accounted for 0.3% of the genome. Tvl RNA, detected in the cell culture, was almost absent in cells of adult flies. A 7-kb polyadenylated RNA was the main transcript of Tvl. Extrachromosomal circular and linear Tvl copies were cloned and characterized. The following features of Tvl structural organization were studied: (1) element was flanked by perfect direct repeats of 453 bp size (long terminal repeats, LTRs); (2) element sequences adjacent to the LTRs were homologous to binding sites of primer serine tRNA and the polypurine blocks of retrotransposons 17.6 and 297; and (3) expected transcription of LTRs occurred as for known retrotransposons, --producing RNA with a direct terminal repeat.
Andrianov
B V
BV
Shuppe
N G
NG
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D017931:DNA Primers; D004251:DNA Transposable Elements; D004270:DNA, Circular; D004330:Drosophila / Q000235:genetics*; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid; D014158:Transcription, Genetic
D017931:DNA Primers; D004251:DNA Transposable Elements; D004270:DNA, Circular
Tv1--novoe semeĭstvo retrotranspozonov Drosophila virilis.