Developmental changes in glycoproteins of the chick nervous system.

Temporal changes have been noted previously in retinal glycoproteins that bind to wheat germ agglutinin by a technique in which the denatured glycoproteins are first separated according to size by polyacrylamide gel electrophoresis, and are then localized on the gel using [125I]lectin. As reported here this technique will also detect differences between dorsal and ventral halves of the neural retina from 8-day chick embryos, and using other lectins will detect temporal changes in the glycoprotein pattern of the optic tectum. Some of the glycoproteins detected by wheat germ agglutinin in the neural retina appear to be represented on the surface of the retinal cells since: (a) the temporal changes in retinal glycoproteins can also be observed in a plasma membrane enriched fraction prepared from neural retina cells; and (b) antibodies prepared in mice against various size categories of wheat germ lectin binding glycoproteins bind to intact retinal cells.