The carbohydrate active enzyme (CAZy) database is an invaluable resource for 
glycobiology and currently contains 45 glycosyltransferase families that are 
represented in plants. Glycosyltransferases (GTs) have many functions in plants, 
but the majority are likely to be involved in biosynthesis of polysaccharides 
and glycoproteins in the plant cell wall. Bioinformatic approaches and 
structural modeling suggest that a number of protein families in plants include 
GTs that have not yet been identified as such and are therefore not included in 
CAZy. These families include proteins with domain of unknown function (DUF) 
DUF23, DUF246, and DUF266. The evidence for these proteins being GTs and their 
possible roles in cell wall biosynthesis is discussed.