Effect of Metabolic Inhibitors on the Formation of Cell Walls in a Green Alga, Micrasterias crux-melitensis

The effects of cytochalasin B, N-ethylmaleimide (NEM), colchicine,vinblastine and cycloheximide on the formation of birefringentcell wall layers were studied. Birefringent layers accumulatedoutside the plasma membrane of daughter semicells when cellswere cultured in a 0.16 M mannitol solution without any inhibitors.In cells treated with 2 x 10^–5 M cytochalasin B, 3 x 10^–5M NEM, 10^–4 M vinblastine or 10^–5 M cycloheximidefor 24 hr, birefringent layers were not observed outside theplasma membrane, but were present in cells treated with 10^–2M colchicine. The possibility is discussed that substances necessaryfor wall synthesis could be transported from the cytoplasm tothe outside of the plasma membrane by a system associated withmicrofilaments, microtubules and myosin-like structures. (Received June 26, 1981; Accepted September 24, 1981)