The inside cover picture shows a recombinant thioester fragment (pink tube) of the gut hormone peptide YY (PYY) used in a semisynthetic strategy for the design of C-terminally modified (blue chemical structure) PYY analogues with potential applications as antiobesity agents. Combining the native chemical ligation–desulfurization approach with a 96-well plate (background) format allowed rapid parallel generation of PYY analogues that were subsequently tested in cell-based GPCR (blue cartoon) assays. For more details, see the Full Paper by Jens Chr. Norrild, Kristian Strømgaard et al. on p. 1505 ff.