Abstract
Allelic assortment of Tetrahymena pyriformis makes possible the isolation of cells which contain both a heterozygous germ line nucleus and a somatic nucleus which expresses phenotypes of only one member of allelic pairs. Cycloheximide-sensitive segregants have been isolated from the vegetative progeny of cells heterozygous for a dominant mutation conferring resistance to cycloheximide; such segregants are called functional heterokaryons. Since progeny from crosses of these cells are cycloheximide-resistant, addition of the drug provides positive selection for successful exconjugants. The timing for expression of the new phenotype during conjugation is presented and used to identify what appear to be immature progeny of round one mating in genomic exclusion. Usefulness of functional heterokaryons in a number of genetic and developmental studies is discussed.
Full Text
The Full Text of this article is available as a PDF (695.5 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Allen S. L. Genomic exclusion: a rapid means for inducing homozygous diploid lines in Tetrahymena pyriformis, syngen 1. Science. 1967 Feb 3;155(3762):575–577. doi: 10.1126/science.155.3762.575. [DOI] [PubMed] [Google Scholar]
- NANNEY D. L. The inheritance of H-L serotype differences at conjugation in Tetrahymena. J Protozool. 1963 May;10:152–155. doi: 10.1111/j.1550-7408.1963.tb01654.x. [DOI] [PubMed] [Google Scholar]
- Nanney D L, Dubert J M. The Genetics of the H Serotype System in Variety 1 of Tetrahymena Pyriformis. Genetics. 1960 Oct;45(10):1335–1349. doi: 10.1093/genetics/45.10.1335. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nanney D. L., Caughey P. A. Mating Type Determination in Tetrahymena Pyriformis. Proc Natl Acad Sci U S A. 1953 Oct;39(10):1057–1063. doi: 10.1073/pnas.39.10.1057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Roberts C. T., Jr, Orias E. A cycloheximide-resistant mutant of Tetrahymena pyriformis. Exp Cell Res. 1973 Oct;81(2):312–316. doi: 10.1016/0014-4827(73)90520-x. [DOI] [PubMed] [Google Scholar]