Fig. 4
From: Insights into degradation mechanism of N-end rule substrates by p62/SQSTM1 autophagy adapter
Recognition of type-1 and type-2 N-degrons by p62. a Molecular surface showing the electrostatic potential of the ZZ-domain (left), yeast UBR box (middle) and E. coli ClpS (right). Bound peptides are shown in white, gray, and cyan as stick models for R-BiP, Arg-Scc1 and Leu-peptide substrates, respectively. Red and blue colors represent negatively and positively charged surfaces, respectively (see Supplementary Fig. 8). b Binding affinity measurements using various FITC-labeled N-degron peptides against increasing concentrations of MBP-PB1-ZZ at pH 8.0. Different line colors and symbols are used to distinguish each peptide. The error bars represent standard error of the mean (S.E.M.) of more than three independent experiments. c Close-up view of the recognition of type-1 N-degrons by the ZZ-domain of p62. d Close-up view of the recognition of type-2 N-degrons by the ZZ-domain of p62. The bound peptide and key residues of p62 are shown as stick models. Nitrogen and oxygen atoms are colored blue and red, respectively. Hydrogen bonding and van der Waals contact distances are marked as dashed lines and labeled. Asn132 of p62 is particularly important for the recognition of type-1 as well as type-2 N-degron substrates (see Supplementary Fig. 9)
