Extended Data Fig. 7: Comparison of SUC1 structure characteristics to computationally predicted inward open model.
From: Structure and sucrose binding mechanism of the plant SUC1 sucrose transporter
a, Extracellular and intracellular charged residues with labeled residues involved in salt bridge formation (black font) or hydrogen bonds (gray font) in the SUC1 outward open crystal structure and in the AlphaFold2 predicted SUC1 inward open state. Yellow dashes indicate hydrogen bonds (Distance and angle cutoffs for H-bonding as defined by default settings in chimeraX v1.4). b, Oocyte uptake assay for SUC1 mutants targeting the hydrogen bonds and salt bridge networks observed in the structure (intracellular network) or predicted (predicted extracellular network), as well as the SUC1 phosphorylation site on Ser20 (P-site). Uptake activities are normalized to that of the wild type. Bars are mean ± s.d. Data points are individual experiments (n = 5 (D304N), n = 6 (D123N, R139A), n = 7 (H65K,D91N,R163K,D306N,E353Q), n = 10 (S20A), n = 13 (WT)). P values for differences between wild type and variants was from a one-way ANOVA analysis followed by Dunnett’s multiple comparisons test (p = 0.1624 (S20A), p = 0.9729 (H65K)). Colors correspond to residue position in Fig. 1e. c, AlphaFold2 prediction of SUC1 inward open model (grey) superimposed to the experimentally determined SUC1 outward open crystal structure (cyan). Yellow dashes indicate hydrogen bonds and grey arrow indicates major movement of the M1 helix with Gln50 (Distance and angle cutoffs for H-bonding as defined by default settings in chimeraX v1.4).
