Functions

The ubiquitous presence of lectins in nature, and their ability to discriminate between closely related saccharides in solution and on cell surfaces, provide a major stimulus for the continuing search for their physiological function(s). A strong argument that lectins indeed have such functions is their conservation throughout evolution as homologous protein families. Another argument is that many of them are developmentally regulated and that their appearance often coincides with distinct physiological changes in the life of an organism. Notably, the putative lectin ligands, i.e. the complementary carbohydrate structures, are often under strict developmental control, too.