Fig. 4.

The glycogenin-1 protein. a Alignment of glycogenin-1 proteins in different species. The bottom three lines demonstrating proteins belonging to other gene families with DxD motif. The amino acid affected by the mutation in red and within the hatched line is the conserved DxD motif. b Illustration of the stereo view of glycogenin-1 with the amino acids in the DxD motif marked with colours, the affected aspartic acid at position 102 in red, alanine and aspartic acid at positions 103 and 104 respectively in green. UDP-glucose is labelled in blue and Mn²⁺ is labelled in purple. This figure was generated using The PyMOL Molecular Graphics System, Version 1.7.2.1 Schrödinger, LLC. c Schematic illustration of the interaction between glycogenin-1, UDP-glucose and Mn²⁺. Amino acids within the DxD motif are included and labelled in colours, the amino acid affected by mutation is in red (modified from Gibbons et al 2002). d Higher magnification of the stereo view demonstrating the UDP-glucose, Mn²⁺ and the DxD motif. The polar contact between UDP-glucose and Asp102 is demonstrated with the yellow-hatched line. The same colour scheme is used throughout the figure