title: Lectin receptors on the plasma membrane of soybean cells. Binding and lateral diffusion of lectins.
abstract: Protoplasts prepared from suspension cultures of root cells of Glycine max (SB-1 cell line) bound soybean agglutinin (SBA), concanavalin A (Con A), and wheat germ agglutinin (WGA). Binding studies carried out with 125I-labeled SBA, Con A, and WGA showed that these interactions were saturable and specific. Fluorescence microscopy demonstrated uniform membrane labeling. The mobility of the lectin-receptor complexes was measured by fluorescence redistribution after photobleaching. The diffusion constants (D) for SBA and Con A were 5 X 10(-11) and 7 X 10(-11) cm2/s, respectively. In contrast, WGA yielded a diffusion constant of 3 X 10(-10) cm2/s. Pretreatment of the protoplasts with either SBA or Con A resulted in a 6-fold reduction in the mobility of WGA (D congruent to 5 X 10(-11) cm2/s). The results suggest that the binding of SBA or Con A may lead to alterations of the soybean plasma membrane which, in turn, may restrict the mobility of other receptors.
mesh_terms: D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D007700:Kinetics; D037102:Lectins / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D037121:Plant Lectins; D010944:Plants / Q000378:metabolism*; D011523:Protoplasts / Q000378:metabolism / Q000648:ultrastructure; D011975:Receptors, Mitogen / Q000378:metabolism*; D013025:Glycine max; D013045:Species Specificity; D013329:Structure-Activity Relationship
chemical_list: D037102:Lectins; D037121:Plant Lectins; D011975:Receptors, Mitogen