MS/MS-based identification of PDF, CAP-3, SIFamide, and a novel NPLP1-derived peptide, NPLP1-2 (DPK peptide), from single fly brains. MS/MS major peak assignments and corresponding sequence tags for: A, PDF; B, CAP-3; C, SIFamide; D, NPLP1-2 (DPK). Light blue asterisk denotes the precursor ion. y-type ions are shown in dark blue. b- and a-type ions shown in red. Iminium ions are shown in green and denoted by the one letter symbol of their respective amino acid followed by an asterisk. Internal fragments (b-y) are shown in green and denoted by their amino acid sequence. Similar results were obtained in duplicate and triplicate analyses.