Colchicine-Induced Effects in the Scaly Green Alga,Mesostigma viride: Loss of Microtubules and Paracrystal Formation

Publisher Website
Google Scholar
Abstract
The effects of colchicine treatment upon the scale-covered, disc-shaped prasinophyte, Mesostigma viride, are profound. 2–4 mg ml−1 of the alkaloid induces the loss of pit and other cytoskeletal microtubules within 6 h of treatment. Subsequently, the organism loses its distinctive shape and becomes ellipsoidal. During treatment, prominent, intracellular crystalline bands consisting of 25 nm hexagonal subunits form in close proximity to the former pit region. The Golgi apparatus remains intact during colchicine application but scale ontogenesis is distinctly altered. All effects are reversible upon removal of colchicine. A discussion of the cytoskeletal role of parallel series of microtubules in unicellular algae is presented.