Intracellular positional control of survival or degeneration of nuclei during conjugation in Paramecium caudatum.

Restoration of membrane excitability in a behavioral mutant of Paramecium caudatum during conjugation and by microinjection of wild- type cytoplasm

When cells of the behavioral mutant cnrC of Paramecium caudatum were mated with the wild type, phenotype change from CNR (no backward swinning) to wild type in the cnrC mate occurred immediately after the formation of tight pairs. No change of phenotype occurred when cells of cnrA or cnrB were mated with wild type. Phenotypic change from CNR to wild type in cells of cnrC was also induced by mic...

Isolation and Characterization of Macronuclei of Paramecium Caudatum Infected with the Macronucleus-specific Bacterum Holospora Obtusa

Endosymbiotic associations between bacteria and eukaryotes are commonly reported (Taylor, 1983). The prokaryotic cell (the cytobiont (Taylor, 1979) or endocytobiont (Schwemmler, 1979)) may live non-specifically within the intracellular habitat provided by the host, but some endosymbiotic bacteria are specialized to invade specific cellular organelles. Three species of the bacterial genus Holosp...

Variation and Inheritance in Abnormalities Occurring after Conjugation in Paramecium caudatum.

Inhibition of mating pair formation by wheat germ agglutinin and wheat germ agglutinin-binding substances in Paramecium caudatum cells

In this study, we revealed that the lectin wheat germ agglutinin (WGA) and its specific binding sugars, N-acetylneuraminic acid (NeuAc) and Nacetylglucosamine (GlcNAc), inhibited mating pair formation in Paramecium caudatum. The concentrations that caused 50% inhibition (IC50) were 17 nM, 3 mM and 30 mM, respectively. Using FITCWGA, it was shown fluorescence-cytochemically that WGA bound to the...

Infection of macronuclear anlagen of Paramecium caudatum with the macronucleus-specific symbiont Holospora obtusa.

The gram-negative bacterium Holospora obtusa is an endonuclear symbiont of Paramecium caudatum, which is incorporated into the host cells via the food vacuoles and infects their macronucleus exclusively, but never the micronucleus. Since these two kinds of nuclei originate from a fertilization nucleus, it is assumed that the macronucleus acquires a property necessary for it to be recognized by ...