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SLACS retrotransposon from Trypanosoma brucei gambiense is similar to mammalian LINEs.

ABSTRACT: We have characterized a retrotransposon in Trypanosoma brucei gambiense uniquely associated with the spliced-leader (SL) RNA gene cluster (Spliced Leader Associated Conserved Sequence, SLACS). There are nine copies of SLACS and DNA sequence analysis of one shows the hallmarks of Line-1 like elements. SLACS has generated a 49 bp target DNA duplication at its insertion site and its 3'-end is preceded by a poly(A) stretch. Two putative open reading frames (ORFs) span 75% of the element. ORF1 has CysHis motif associated with the retroviral gag polypeptide while ORF2 shows homology with reverse transcriptase sequences. Its 5'-end contains a repeated segment of a 185 bp that varies in copy number in different SLACS insertions. Retrotransposon-like sequences inserted into the SL-RNA genes occur in several hemoflagellates. These elements may represent a related family which has maintained its target site specificity.

SUBMITTER: Aksoy S

PROVIDER: S-EPMC330328 | biostudies-other | 1990 Feb

REPOSITORIES: biostudies-other

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SLACS retrotransposon from Trypanosoma brucei gambiense is similar to mammalian LINEs.

Aksoy S S Williams S S Chang S S Richards F F FF

Nucleic acids research 19900201 4

We have characterized a retrotransposon in Trypanosoma brucei gambiense uniquely associated with the spliced-leader (SL) RNA gene cluster (Spliced Leader Associated Conserved Sequence, SLACS). There are nine copies of SLACS and DNA sequence analysis of one shows the hallmarks of Line-1 like elements. SLACS has generated a 49 bp target DNA duplication at its insertion site and its 3'-end is preceded by a poly(A) stretch. Two putative open reading frames (ORFs) span 75% of the element. ORF1 has Cy ...[more]

PMID: 2156231

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