Fig. 3.

A representative modified proteoform of Gng5. (A) Tandem mass spectrum with annotated fragments and (B) fragment error map. Despite the relatively low sequence coverage, the b/y ions supported assignment of N-terminal acetylation and S-geranylgeranyl modification at the cysteine near the C-terminus (scan #3185 in Hubmap_Intact_Brain_C1_CV40.raw). The unlabeled peaks < m/z 600 were presumably from other co-isolated species (supplemental Fig. S5).