ISSN:
1432-0878
Keywords:
Nuclear division
;
Protozoan
;
Ultrastructure
;
Microtubules
;
Colchicine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Ultrastructural changes in the micro- and macronucleus throughout division were followed in synchronized cultures of the suctorian, Tokophrya infusionum. After an initial swelling, the micronucleus elongates enormously; microtubules within the micronucleus proliferate and lengthen as the micronucleus elongates. Changes in the macronucleus become visible only after micronuclear division is well underway. The chromatin bodies fuse into long chromatin strands, and the large bundles of microtubules present in the resting macronucleus break up into small groups which parallel the chromatin strands. Colchicine, which prevents reproduction in Tokophrya, seems to block division at a very early stage. The macronucleus appears the same as the resting nucleus of untreated organisms, with numerous microtubules and distinct chromatin bodies. The chromatin in the micronucleus aggregates into large clumps, however, and proliferation of microtubules does not occur.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00391122