Cladogram of UDP-glucose 4-epimerases. The phylogenetic relationships of UGEs from different organisms are shown. Two vascular plant UGE families described by Kotake et al.  are highlighted. UGEs that have documented UDP-Xyl 4-epimerase activity are marked with asterisks. The tree was generated using the Neighbor-Joining method, the bootstrap consensus tree inferred from 1000 replicates (MEGA6 program). Bootstrap values greater than 60% are indicated. Species and accession numbers are described in the Methods section.