Genomic organization of the transposable element Tdd-3 from Dictyostelium discoideum.
The transposable element Tdd-3 from D. discoideum has been described originally in 1984 (Poole and Firtel, 1984). Additional copies of this element were discovered in the course of a recent study on tRNA gene organization in D. discoideum. Five out of 24 independently isolated tRNA genes proved to be associated with Tdd-3 elements. The surprising observation that all the elements always occurred within the 3'-flanking sequences of the Dictyostelium tRNA genes suggested the possibility of a general position specific integration of Tdd-3 elements upon transposition. Therefore we isolated additional Tdd-3 elements from various genomic D. discoideum libraries in order to test this hypothesis. Several new Tdd-3 elements were found associated with various tRNA genes. Additionally we identified Tdd-3 elements organized in tandem array or in association with RED (Repetitive Element of Dictyostelium), another repetitive element recently identified by our laboratory. In all cases a B-box equivalent of the eukaryotic gene-internal RNA polymerase III promoter was identified upstream of all Tdd-3 elements.
Marschalek
R
R
Institut für Biochemie, Medizinische Fakultät, Universität Erlangen-Nürnberg, FRG.
Borschet
G
G
Dingermann
T
T
D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D004023:Dictyostelium / Q000235:genetics*; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D012331:RNA, Fungal / Q000235:genetics; D012343:RNA, Transfer / Q000235:genetics*; D015183:Restriction Mapping
D004251:DNA Transposable Elements; D012331:RNA, Fungal; D012343:RNA, Transfer