THE PLANT CELL, Vol 1, Issue 5 511-514, Copyright © 1989 by American Society of Plant Biologists
N-Linked Glycan Chains on S-Allele-Associated Glycoproteins from Nicotiana alata
J. R. Woodward, A. Bacic, W. Jahnen and A. E. Clarke
Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Parkville, Victoria 3052, Australia
The products of the self-incompatibility locus of flowering plants are
glycoproteins. The specificity of different alleles at this locus might be
expressed through differences in either amino acid sequences or by the
glycan substituents. We have investigated the numbers of N-linked glycan
chains on the S-glycoproteins and obtained information on their structure
by enzymic cleavage with N-glycanase and
endo-[beta]-N-acetylglucosaminidase H. In addition to there being variation
in the numbers of chains on the S-glycoproteins, each glycoprotein appears
to consist of a spectrum of "glycoforms" bearing chains of differing type
and fine structure. This microheterogeneity in N-linked glycan chains may
be functionally significant.