Skip to main content
Genetics logoLink to Genetics
. 1973 May;74(1):81–106. doi: 10.1093/genetics/74.1.81

Regulatory Serotype Mutations in TETRAHYMENA PYRIFORMIS, Syngen 1

F P Doerder 1
PMCID: PMC1212939  PMID: 17248612

Abstract

A method utilizing allelic exclusion has been developed to isolate mutants of Tetrahymena pyriformis, syngen 1, in which the normal pattern of expression of mutally exclusive surface antigens is altered. Cells homozygous for the recessive mutant allele R-1r do not express the L, H and T serotypes when grown under conditions appropriate for their expression. Rather, a new immobilization antigen, r, is expressed. Cells homozygous for the recessive mutant allele R-3r also express the r antigen instead of H serotypes, but are normal in their expression of T antigens. Genetic analyses show that R-1 and R-3 are not closely linked, that R-1 is linked to T by 9.3 units, and that R-3 may be loosely linked to the mt locus. Different linkage values were obtained, however, when different inbred laboratory strains were used, suggesting the possible existence of crossover modifying genes. The rates of assortment of R-1R/R-1r and R-3R/R-3r heterozygotes into pure sublines expressing either H or r serotypes are close to the values observed for the differentiation of heterozygotes at other loci. The data confirm the previous observation that genetic coupling relationships are not maintained in macronuclear phenotypes and are consistent with the hypothesis that the macronucleus contains 45 assorting subunits. The assortment of the double heterozygote R-1R/R-1r, R-3R/R-3r at Rf=0.0112 suggests that the units of assortment are not individual genetic loci or chromosome fragments, but that the units may be complete genomes.

Full Text

The Full Text of this article is available as a PDF (1.7 MB).

Selected References

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

  1. Allen S L. Inherited Variations in the Esterases of Tetrahymena. Genetics. 1960 Aug;45(8):1051–1070. doi: 10.1093/genetics/45.8.1051. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Allen S. L., Lee P. H. The preparation of congenic strains of Tetrahymena. J Protozool. 1971 May;18(2):214–218. doi: 10.1111/j.1550-7408.1971.tb03309.x. [DOI] [PubMed] [Google Scholar]
  3. Ammermann D. Morphology and development of the macronuclei of the ciliates Stylonychia mytilus and Euplotes aediculatus. Chromosoma. 1971;33(2):209–238. doi: 10.1007/BF00285634. [DOI] [PubMed] [Google Scholar]
  4. Andersen H. A., Zeuthen E. DNA replication sequence in Tetrahymena is not repeated from generation to generation. Exp Cell Res. 1971 Oct;68(2):309–314. doi: 10.1016/0014-4827(71)90155-8. [DOI] [PubMed] [Google Scholar]
  5. Bleyman L. K., Simon E. M. Clonal analysis of nuclear differentiation in Tetrahymena. Dev Biol. 1968 Sep;18(3):217–231. doi: 10.1016/0012-1606(68)90033-x. [DOI] [PubMed] [Google Scholar]
  6. Carlson P. S. Mutant Selection in TETRAHYMENA PYRIFORMIS. Genetics. 1971 Oct;69(2):261–265. doi: 10.1093/genetics/69.2.261. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Juergensmeyer E. B. Serotype expression and transformation in Tetrahymena pyriformis. J Protozool. 1969 May;16(2):344–352. doi: 10.1111/j.1550-7408.1969.tb02280.x. [DOI] [PubMed] [Google Scholar]
  8. Kidwell M. G. Genetic change of recombination value in Drosophila melanogaster. I. Artificial selection for high and low recombination and some properties of recombination-modifying genes. Genetics. 1972 Mar;70(3):419–432. doi: 10.1093/genetics/70.3.419. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Phillips R. B. Inheritance of T serotypes in Tetrahymena. Genetics. 1967 Aug;56(4):667–681. doi: 10.1093/genetics/56.4.667. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Genetics are provided here courtesy of Oxford University Press

RESOURCES