Synthesis of Polysaccharides in Phragmoplasts Isolated from Tobacco BY-2 Cells

Abstract

Autoradiographic experiments using preparations of isolated phragmoplast obtained from tobacco cultured cells revealed that the radioactivity incorporated into insoluble material from UDP-[3H]glucose was exclusively present at the cell plate of isolated phragmoplasts. Most of the radioactivity incorporated into isolated phragmoplasts from UDP-[14C]glucose was solubilized by 1,3-β-glucanase and the solubilized radioactivity was associated only with glucose, indicating that most of the radioactivity was incorporated into 1,3-β-glucan. In the presence of high concentrations of unlabeled UDP-glucose, isolated phragmoplasts incorporated radioactivity from UDP-[3H]xylose. Most of the radioactivity incorporated into insoluble material was present at several sites distributed around the nuclei, while only little was found at the cell plate.