Genetics, Vol 134, 189-198, Copyright © 1993


INVESTIGATIONS

Molecular and Genetic Analyses of the B Type Surface Protein Gene from Paramecium tetraurelia

J. Scott, C. Leeck and J. Forney
Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907

The gene encoding the B type variable surface protein from Paramecium tetraurelia stock 51 has been cloned and sequenced. The 7,182 nucleotide open reading frame contains no introns and encodes a cysteine-rich protein that has a periodic structure including three nearly perfect tandem repeats in the central region. Interestingly, the B gene is located near a macronuclear telomere as was shown previously for two other paramecium surface protein genes. In this paper, we characterize four independent mutants with complete macronuclear deletions of the B gene. Previous analysis of different macronuclear deletion mutants of the A surface protein gene demonstrated two types of inheritance: typical Mendelian segregation (as illustrated by d12) and cytoplasmic inheritance (shown by d48). F(1) analysis of four B(-) mutants crossed with wild-type cells reveals heterozygous F(1) cell lines derived from both parental cytoplasms contain approximately the same copy number of the B gene, as expected for a recessive Mendelian mutation. Analysis of F(2) progeny from three of these four B(-) mutant crosses indicates that one of the three exhibits a Mendelian 1:1 segregation ratio of B(+) and B(-) cell lines. The other two show a preponderance of B(+) cells, but this is not correlated with the parental cytoplasmic type. In addition to having a large number of B(+) individuals, the d12.144, A(-), B(-) mutant produced some F(2) progeny that stably maintain less than normal macronuclear amounts of the A gene and/or the B gene.


This article has been cited by other articles:


Home page
Eukaryot CellHome page
A. Matsuda and J. D. Forney
Analysis of Paramecium tetraurelia A-51 Surface Antigen Gene Mutants Reveals Positive-Feedback Mechanisms for Maintenance of Expression and Temperature-Induced Activation
Eukaryot. Cell, October 1, 2005; 4(10): 1613 - 1619.
[Abstract] [Full Text] [PDF]


Home page
Eukaryot CellHome page
A. Le Mouel, A. Butler, F. Caron, and E. Meyer
Developmentally Regulated Chromosome Fragmentation Linked to Imprecise Elimination of Repeated Sequences in Paramecia
Eukaryot. Cell, October 1, 2003; 2(5): 1076 - 1090.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
C. A. PAQUETTE, V. RAKOCHY, A. BUSH, and J. L. V. HOUTEN
GLYCOPHOSPHATIDYLINOSITOL-ANCHORED PROTEINS IN PARAMECIUM TETRAURELIA: POSSIBLE ROLE IN CHEMORESPONSE
J. Exp. Biol., March 10, 2002; 204(16): 2899 - 2910.
[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
M.-C. Gautier, L. Sperling, and L. Madeddu
Cloning and Sequence Analysis of Genes Coding for Paramecium Secretory Granule (Trichocyst) Proteins
J. Biol. Chem., April 26, 1996; 271(17): 10247 - 10255.
[Abstract] [Full Text] [PDF]