Extended Data Fig. 6: Validation of the β5 Propeptide Structure by Crosslinking Mass Spectrometry.
From: Mechanism of autocatalytic activation during proteasome assembly
Crosslinking mass spectrometry was performed on β3-D205Δ proteasomes, which identified two crosslinks involving the β5-propeptide: β5-D61/D62 with β5-D193, and β5-E27 with α5-E131. A third crosslink, β5-K16 with α6-K115, was detected in a prior study13. All three crosslinks are within the crosslinkable distance for the respective Lys-Lys and Asp/Glu-Asp/Glu crosslinkers, and strongly support the modeled structure of the β5-propeptide. The orange dashed lines indicate the crosslinked residues. The other colored dashed lines indicate unresolved residues.
