GENETIC ANALYSES OF "PARANOIAC" MUTANTS OF PARAMECIUM TETRAURELIA

Judith Van Houten ¹, Sheng-Yung Chang ¹, and Ching Kung ¹

¹ Laboratory of Molecular Biology and Department of Genetics, University of Wisconsin, Madison, Wisconsin 53706

Six mutants of Paramecium tetraurelia with curious "Paranoiac" phenotypes have been isolated and examined. Instead of the normal transient avoiding reactions in Na⁺ solutions, these mutants show "violent avoidances"—backing continuously for 10 to over 60 sec. This behavior corresponds to prolonged membrane excitation.—Genetic analyses establish five genic loci at which mutations give the "Paranoiac" phenotype. Close linkage between two of these genes occurs. Allelic variants are found for two of the genes. In one case, the two alleles determine very different behavioral phenotypes ("Paranoiac" and "fast-2"). These results show that the mechanism(s) which shuts off excitation in the wild-type membrane is (are) complex, but in the future may be fruitfully pursued in mutants which are defective.

This article has been cited by other articles:

				B. Wang, K. M. C. Sullivan, and K. Beckingham Drosophila Calmodulin Mutants With Specific Defects in the Musculature or in the Nervous System Genetics, November 1, 2003; 165(3): 1255 - 1268. [Abstract] [Full Text] [PDF]

				J. A. Hammond and R. R. Preston Isolation and Characterization of Magbane, a Magnesium-Lethal Mutant of Paramecium Genetics, July 1, 2001; 158(3): 1061 - 1069. [Abstract] [Full Text] [PDF]

				B. Byrne and B. Byrne An ultrastructural correlate of the membrane mutant "paranoiac" in Paramecium Science, March 10, 1978; 199(4333): 1091 - 1093. [Abstract] [PDF]