ISSN:
1615-6102
Keywords:
Monensin
;
Ionophore
;
Euglena
;
Golgi apparatus
;
Dictyosome
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Euglena gracilis was treated in 10-5 M monensin for various times from 2 minutes to 24 hours, and then processed for electron microscopy by fixation in glutaraldehyde and osmium tetroxide or potassium permanganate. Monensin affected the mature (trans) half of the cisternae but not the forming (cis) half of the cisternae. After glutaraldehyde and osmium tetroxide fixation, the affected cisternae appeared swollen, whereas after potassium permanganate fixation, the affected cisternae were distorted but not swollen. The monensin effect was first noticeable after 5 minutes of treatment and the maximum effect was observed after only 10 minutes of treatment. No additional monensin effects were observed up to 24 hours of treatment; however, by 24 hours there was variability in dictyosome form and some dictyosomes appeared relatively normal. The first noticeable effects at the 5 minute treatment time involved either the most mature (trans) cisterna or cisternae in the middle of the stack. Thus, inEuglena, the region of the Golgi apparatus that responds to monensin by cisternal dilation is restricted to the mature (trans) half of the dictyosomes, with the initial response given by specific cisternae in the stack.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01279875
