Glycosyltrasferase activity in developing sea-urchin embryos.

The developmental course of activity changes of 4 endogenous membrane glycosyltransferases: UDP-glucose : glycosyltrasferase, UDP-galactose : glycosyltransferase, GDP-mannose: glycosyltransferase, and UD-PN-acetylglucosamine : glycosyltransferase was determined in various stages of developing sea-urchin embryos from unfertilized eggs up to the 16-cell stage. The results show that there is a 2-fold increase in glycosyltransferase activity after fertilization. These results are discussed in relation to the postulated role of glycosyltransferases in mediating adhesion, recognition, and agglutination of cells and embryos.