Dynamin and dynamin-related proteins (DRPs) mediate an array of membrane fission processes. A Tetrahymena DRP has adopted a new role, assisting in nuclear differentiation, a finding that further highlights these proteins - and this ciliate - as biological innovators.

We explore the interactions of CYT-19, a DExD/H-box protein that functions in folding of group I RNAs, with a well characterized misfolded species of the Tetrahymena ribozyme. Consistent with its function, CYT-19 accelerates refolding of the misfolded RNA to its native state. Unexpectedly, CYT-19 performs another reaction much more efficiently; it unwinds the 6-bp P1 duplex formed between the r...

The toxicity of thirty para-substituted phenols on Tetrahymena pyriformis was modelled using an original methodology that uses the complex structural information of the compounds. Two models were built. The methodology allows atomic properties to be assigned to toxicity based on the selection of pairs of descriptors from the entire family, which is called Molecular Descriptors Family (MDF). One...

We have examined the fatty acid composition of the mitochondrial membranes in three strains of Tetrahymena pyriformis. All three had similar components and exhibited large amounts of unsaturated fatty acids. The cytoplasmic mutant, CA-10, which has a slower growth rate and unusual membrane morphology, had a slightly higher amount of iso-acids but was otherwise similar to the other strains in fa...

Cytochalasin B (37 fig per ml) reduces the rate of food vacuole formation, i.e. the rate of phagocytosis, in Tetrahymena pyriformis. Cytochalasin B in this concentration suppresses multiplication rates in a nutrient medium consisting of 2 % proteose peptone, but multiplication is unaffected if this medium is supplemented with glucose and high concentrations of nucleosides. Thus nutrients in hig...

This study asks two questions: 1) whether Hsp90 is involved in the regulation of cortical patterning in Tetrahymena, and 2) if it is, whether specific defects in this regulation can be attributed to functional insufficiency of the Hsp90 molecule. To address question 1, we compared the effects of a specific inhibitor of Hsp90, geldanamycin, on population growth and on development of the oral app...

3-Amino-1-propanol (AP), a substance replacing ethanolamine in phosphatidylethanolamine (PE) significantly reduced 32P incorporation to phosphatidylinositol (PI) and glycosyl-phosphatidylinositol (GPI) in the unicellular organism Tetrahymena pyriformis. At 10 mM, AP completely inhibited the incorporation of 32P into PI. 3H-arachidonate incorporation into PI was also inhibited, while that into d...