Using monoclonal antibody to actin (MAB) and phalloidin, F- and G-actin were demonstrated separately in the unicellular Tetrahymena. MAB labeled mucocysts, basal body cage complexes, the surface of food vacuoles and the surface of the nucleus. A bright fluorescent globular structure was seen attached to the nucleus. Some labels were present along the oral field. Phalloidin labeled these structures similarly, except the bright nucleus-attached globular structure. However, phalloidin labeled contractile vacuoles in some cases. C2-ceramide treatment weakened MAB labeling in general and abolished the fluorescence of the bright nucleus-associated area. Nevertheless basal body cage complexes remained unchanged. Under the effect of this cell permeable ceramide analogue, extremely large vacuoles appeared at the bottom of the cells, and the bright phalloidin labeling of the epiplasmic area (basal body cage complexes, mucocysts) disappeared. Non-hydroxy fatty-acid ceramide influenced the cytoskeleton similarly. There was no detectable alteration after treatment with hydroxy fatty-acid ceramide and sphingosine-1-phosphate. The experiments call attention to the ceramide regulation of cytoskeleton in Tetrahymena and to the possibility of differences in this regulation depending on the cellular localization and forms (G and F) of actin.
|Number of pages||8|
|Publication status||Published - Dec 1 1998|
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)