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. 1991 Aug 1;88(15):6711–6715. doi: 10.1073/pnas.88.15.6711

Stable transformation of Leptomonas seymouri by circular extrachromosomal elements.

V Bellofatto 1, J E Torres-Muñoz 1, G A Cross 1
PMCID: PMC52158  PMID: 1713688

Abstract

To define the cis-acting sequences necessary for gene expression and DNA replication in trypanosomatids, we have developed a selectable vector that can be grown in Escherichia coli and maintained stably in the insect trypanosomatid Leptomonas seymouri. The vector is relatively small (6 kilobase pairs) and contains a portion of the L. seymouri alpha-tubulin gene positioned in-frame with a truncated neomycin phosphotransferase gene that confers resistance to the aminoglycoside G418. This construct is maintained in cells as a high-copy-number circular extrachromosomal element containing several head-to-tail copies of the transforming plasmid. In L. seymouri, alpha-tubulin-neomycin phosphotransferase fusion RNAs are polyadenylylated and possess a trans-spliced mini-exon. Additional DNA sequences can be inserted into the vector, propagated, and expressed in transformed cells.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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