Postnatal changes in lectin binding to microvillus membranes from rat intestine.
The intestinal microvillus membrane of suckling rats has a large number of unsubstituted and sialyl-substituted sites for 125I-labeled peanut agglutinin in glycopeptides, indicating that the membrane surface is rich in beta, D-Gal(1 leads to 3)D-GalNAc residues. The membrane loses all the unsubstituted and about half of the sialyl-substituted PNA-reactive sites during weaning. Simultaneously, there occur increases in the bindings of 125I-labeled soybean lectin and 125I-Ricinus communis toxin to unsubstituted sites in glycopeptides. This indicates appearance of new terminal nonreducing D-GalNAc and D-Gal in glycopeptides in the mature membranes. The developmental loss of PNA reactive sites from the microvillus membrane in rat intestine is probably related to D-GalNAc substitution in O-glycans of mucin-type glycoproteins, and to steric hindrance arising in the course of glycosylation.
D000818:Animals; D001665:Binding Sites; D006023:Glycoproteins / Q000378:metabolism; D007413:Intestinal Mucosa / Q000254:growth & development / Q000378:metabolism*; D037102:Lectins / Q000378:metabolism*; D008560:Membrane Fluidity; D008563:Membrane Lipids; D008871:Microvilli / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains / Q000254:growth & development
D006023:Glycoproteins; D037102:Lectins; D008563:Membrane Lipids