Regulation of callose metabolism in higher plant cells in vitro

Temporary accumulation of callose in suspension-cultured wheat (Triticum timopheevii Zhuk.) cells at the exponential growth phase was correlated with the mitotic index due to the formation of the cell plates in dividing cells. Callose disappeared in expanding cells owing to enhanced activities of endo- and exoglucanases. The exogluconase activity was reduced when the cells were treated with cycloheximide, an inhibitor of protein synthesis. A similar pattern was observed when elicitors experimentally enhanced callose synthesis. Apparently, in such cases, callose behaves as a temporary component repairing the cell wall. We presume that plant cells comprise a universal mechanism for regulating callose synthesis.