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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1992 Oct 1;89(19):9196–9200. doi: 10.1073/pnas.89.19.9196

Efficient mass transformation of Tetrahymena thermophila by electroporation of conjugants.

J Gaertig 1, M A Gorovsky 1
PMCID: PMC50092  PMID: 1409625

Abstract

Conjugating cells of the ciliate Tetrahymena thermophila were electroporated in the presence of plasmid DNA containing a paromomycin-resistant ribosomal RNA gene (rDNA). Cells were selected with paromomycin following 12-24 hr of growth on nonselective medium. Resistant cells appeared after 2-3 days. Processing vectors containing the micronuclear rDNA and somatic vectors containing the macronuclear gene transformed the cells, with the former yielding frequencies up to 900 transformants per microgram of plasmid DNA. A ribosomal protein gene (rpL29) conferring cycloheximide resistance also transformed conjugating cells. The transformation efficiency of the plasmid containing only the rpL29 gene was increased by insertion of an rDNA replication origin and by cotransformation and preselection with an rDNA vector. These results indicate that electroporation can be used for the production of large numbers of transformed Tetrahymena.

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Selected References

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