Extended Data Fig. 1: Purification and preliminary characterization of GYS1:GYG1 complexes.
a, Coomassie stained SDS-PAGE of small-scale test purifications of GYS1 complexed with differently tagged truncated GYG1. b, Coomassie stained SDS-PAGE of the three GYS1:GYG1 complexes used in this study. c, Blue native PAGE of the three GYS1:GYG1 complexes used in this study. d, Example micrographs of GYS1:GYG1FL and GYS1:GYG1ΔCD complexes collected using a Glacios microscope. e, 2D classes of the GYS1:GYG1ΔCD complex from an initial dataset collected using a Glacios microscope. Arrows indicate regions of fuzzy density protruding from an inter-subunit interface. f, Denaturing mass-spectra of GYS1 and GYG1, as purified and treated with PP1. g, UDP-Glo activity assay of the three GYS1:GYG1 constructs without and with exogenous glycogen. ‘Full’ is the activity assay with all substrates. ‘- Glycogen’ is the assay carried out in the absence of exogenously added glycogen. ‘- Glc6P’ is the assay carried out in the absence of Glc6P. Median and standard deviation of activity is shown (n = 3 technical repeats).
