The role of Golgi bodies in polysaccharide sulphation in Fucuszygotes.
The cell wall of 24-h zygotes of Fucus serratus is composed of 3 layers--an inner fibrillar layer (sulphated fucan), an outer fibrillar layer (alginic aicd/cellulose) and an exterior amorphous layer (sulphated fucan, alginic acid). The 2 layers containing sulphated fucan are preferentially thickened at the rhizoid pole. Light- and electron-microscope autoradiographic pulse-chase experiments on 22-h zygotes using 35SO2-(4) show the Golgi bodies to be the sites of fucan sulphation. The isolation and characterization of isolated Golgi-rich fractions from 22-h zygotes shows that the first detectable labelled macromolecule is associated with these fractions 2 min after addition of 35SO2-(4). The sulphate acceptor molecule has been partially characterized. 35S-APS and 35S-paps are detectable in the soluble fraction 0.5 min after addition of 35SO2-(4). The results are discussed in relation to other published work on the differentiation of Fucus embryos and on polysaccharide sulphation.
D001345:Autoradiography; D002458:Cell Fractionation; D002473:Cell Wall / Q000032:analysis / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000032:analysis / Q000502:physiology*; D006651:Histocytochemistry; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D011134:Polysaccharides / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism / Q000648:ultrastructure*; D013431:Sulfates / Q000378:metabolism
D011134:Polysaccharides; D013431:Sulfates