Reactivation of a glycerinated model of Amoeba


Motile models ofAmoeba proteus prepared by extraction at −20 °C with a 50% buffered glycerol solution showed remarkable contraction on addition of Mg-ATP with retainment of Ca++ sensitivity. The initial contraction around the nucleus occurred on addition of Mg-ATP independently of the Ca++ concentration, and was followed by contractions of three different patterns. In 10−8M Ca++, the granuloplasm contracted as a whole and separated from the membrane leaving no detectable particles in the anterior region. In 10−6M Ca++, the granuloplasm contracted leaving some granules which showed active and vigorous two-directional streaming similar to that in the living cell. Sometimes a part of the plasma membrane twitched. The streaming lasted up to 20 minutes. In 10−4M Ca++, after the initial contraction around the nucleus, no significant movement was observed. All these movements in the models were inhibited by cytochalasin B or N-ethylmaleimide. The relationship between the Mg-ATP and the Ca++ concentrations was examined.

DOI: 10.1007/BF01287635

6 Figures and Tables


Citations per Year

155 Citations

Semantic Scholar estimates that this publication has 155 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Kuroda2005ReactivationOA, title={Reactivation of a glycerinated model of Amoeba}, author={Kiyoko Kuroda and Seiji Sonobe}, journal={Protoplasma}, year={2005}, volume={109}, pages={127-142} }