Sugar-coated pathways for developmental patterning

Signalling pathways controlling developmental cell fate rely on a variety o f carbohydrate-based protein modifications, including glycosylation of cell -surface and extracellular-matrix proteins. Receptors themselves might be g lycosylated during synthesis and secretory trafficking, regulating their su bsequent signalling activities. Two recent reports have uncovered a shared requirement for nucleotide-sugar transport in these processes, underscoring the importance of carbohydrates in developmental patterning.