Oligosaccharide signalling molecules

After an additional 10 years of research it is still not entirely clear what the signaling molecule is. Van Bel and Gaupels (2004) recently reviewed the possible signaling molecules that could induce SAR. The list includes jasmonic acid, lipid-derived molecules, reactive oxygen species (see Chapter 2, Section 1.9), oligosaccharides, mRNA molecules, calcium, and various peptides. 

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