We show here the 3D structure of the N-acetylmannosamine kinase domain of GNE, the only ROK family kinase encoded in the human genome. The kinase domain dimerizes through an Data of missense mutations were extracted from reference [11] and [24] . b UDP-GlcNAc epimerase and ManNAc kinase activities are percentage values relative to the corresponding activities of the full length wild type GNE. Data extracted from reference [11] . c Oligomeric state of the full length mutant GNE. Data extracted from reference [11] . d Relative solvent accessibility of the residue calculated using the DSSP program [30] and normalized according to values in reference [31] . A value of 1 means full exposure of the residue while a value of 0 means the residue is fully buried. e The type of the secondary structure element the residue is located at was assigned using the DSSP program [30] . doi:10.1371/journal.pone.0007165.t001