Adhesive and growth properties of lectin from the ascidian Didemnum ternatanum on cultivated marine invertebrate cells

The effects of N-Acetyl-D-glucosamine-specific lectin (M-r 27 kDa) isolated from the ascidian Didemnum ternatanum on cultivated cells of molluscs and echinoderms were studied. This lectin was found to stimulate the growth or the differentiation of cultivated marine invertebrate cells depending on th e stage of embryonic development at which primary cell cultures were obtain ed. In addition, it has been shown to increase the attachment of cells in p rimary cultures of these animals. The degree of attachment is considerably increased when collagen or polylysine substrates are used. Using scanning e lectron microscopy we have demonstrated the stage-specific effect of this l ectin on embryonic sea urchin and molluscan cells. Intensive cell spreading and an alteration of cell shape were observed only at the gastrula stage, when the switching from maternal information to embryonic genes occurred. T he ascidian lectin seems to have some characteristics of both an adhesive f actor and a growth factor. (C) 1999 Elsevier Science B.V. All rights reserv ed.