title: The effects of lithium chloride on pattern formation in Tetrahymena thermophila.
abstract: Lithium ions have long been known to exert dramatic effects on the specification of cell fates in multicellular systems. We have analyzed the effects of Li+ on intracellular patterning in a complex unicellular organism, the ciliate Tetrahymena thermophila. LiCl does not affect the locations of major structural landmarks in the cortical region of wild-type cells and does not modify the phenotype of pattern-mutant cells. However, in all strains studied LiCl differentially affects early stages of oral development. It initially triggers a slow regression of oral primordia, which is followed by an excessive proliferation of basal bodies that leads to a hypertrophy of the ciliature of the cell's feeding organelle. This hypertrophy mimics the effects of the membranellar-pattern-D mutation, the phenotype of which is enhanced in the presence of LiCl. These effects were partially reversed by myo-inositol; however, neomycin failed to mimic the effects of LiCl. Thus, although lithium ions have major cellular effects on Tetrahymena, they do not influence the specification of the body plan in a manner analogous to that observed in multicellular organisms and may work in part through mechanisms other than the now-classical inositol-phosphate cycle.
authors.affiliation: Department of Biological Sciences, University of Iowa, Iowa City 52242-1324, USA.
authors.forename: M
authors.initials: M
authors.lastname: Jerka-Dziadosz
authors.forename: J
authors.initials: J
authors.lastname: Frankel
mesh_terms: D000818:Animals; D007294:Inositol / Q000494:pharmacology; D007295:Inositol Phosphates / Q000378:metabolism; D018021:Lithium Chloride / Q000494:pharmacology*; D009355:Neomycin / Q000494:pharmacology; D010641:Phenotype; D016808:Tetrahymena thermophila / Q000187:drug effects / Q000254:growth & development*
chemical_list: D007295:Inositol Phosphates; D007294:Inositol; D018021:Lithium Chloride; D009355:Neomycin