Synaptic cleft glycoproteins contain homologous amino acid sequences

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Science  23 Apr 1982:
Vol. 216, Issue 4544, pp. 422-424
DOI: 10.1126/science.7071591


The concanavalin A--binding glycoproteins of the rat synaptic junction were isolated by affinity chromatography. These glycoproteins had molecular weights of 160,000, 123,000, 110,000, and 95,000. The tryptic peptide maps of these glycoproteins showed that the three largest glycoproteins contained a high percentage of identical peptides. This indicates that the amino acid sequences of these glycoproteins have a high degree of homology. The 95,000-dalton glycoprotein was unrelated to the other three. These findings suggest that homologous glycoproteins may participate in synapse formation or maintenance, or both.