Table 1.
Peaks observed in MALDI-TOF MS profile spectra confirmed to be neuropeptides by MALDI-TOF/TOF MS/MS fragmentation
| Obs. m/z (Calc. m/z ) | Precursor (UniProtKB Entry name) | Peptide name | Peptide sequence | Previous ref. |
|---|---|---|---|---|
| 925.481* (925.436) |
FMRF_DROME |
PDNFMRFamide |
R.PDNFMRFa.G |
[1,2,7,9,30] |
| 974.592 (974.589) |
SNPF_DROME |
RLRF peptide 2 |
R.SPSLRLRFa.G |
[1,2,9,18,19,30] |
| 1182.578 (1182.573) |
FMRF_DROME |
DPKQDFMRFamide (FMRFamide 2) |
R.DPKQDFMRFa.G |
[1,2,7,9,19,30] |
| 1247.658 (1247.653) |
NEMS_DROME |
Dromyosuppressin (TDVDHVFLRFamide) |
R.TDVDHVFLRFa.G |
[1,2,7,9,18,19,30] |
| 1395.748 (1395.753) |
Q59E62_DROME |
SIFamide (IFa-1) |
A.AYRKPPFNGSIFa.G |
[1,2,9,18,19] |
| 1430.745 (1430.754) |
CP2B_DROME |
CAP-3AA2-AA15 |
T.GPSASSGLWFGPRLa.G |
[1,2,9,19,30] |
| 1471.791 (1471.773) |
NPLP1_DROME |
MTYamide peptide [NPLP1 (MTY)] |
R.YIGSLARAGGLMTYa.G |
[1,2,7,9,18,19] |
| 1531.812 (1531.802) |
CP2B_DROME |
CAP-3 (CAPA-3) |
R.TGPSASSGLWFGPRLa.G |
[1,2,9,19,30] |
| 1534.819 (1534.834) |
NPLP1_DROME |
NPLP1-4 [NPLP1 (VQQ)] |
R.NLGALKSSPVHGVQQ.K |
[1,2,18,19] |
| 1653.907 (1653.908) |
NPLP1_DROME |
IPNamide [NPLP1 (IPN)] |
R.NVGTLARDFQLPIPNa.G |
[1,2,7,9,18,19,30] |
| 1972.015 (1972.017) |
PDF_DROME |
Neuropeptide PDF |
R.NSELINSLLSLPKNMNDAa.G |
[19] |
| 1991.044 (1991.043) |
NPLP1_DROME |
NPLP1-3AA1-AA18 [QRAamide] |
R.NVAAVARYNSQHGHIQRAa.G |
Novel |
| 2094.091 (2094.088) |
NPLP1_DROME |
NPLP1-2 [NPLP1 (DPK)] |
R.NIATMARLQSAPSTHRDPK.R |
Novel |
| 2249.130 (2249.128) | NPLP1_DROME | NPLP1-3 [NPLP1 (GAE)] | R.NVAAVARYNSQHGHIQRAGAE.K | Novel |
Listed are D. melanogaster neuropeptides identified in this study. The final three listings are believed to be novel. Reported observed m/z’s are the average of the m/z’s observed between the two replicate experiments MALDI-TOF MS experiments described. All observed m/z’s listed were determined to be monoisotopic [M + H]+’s of listed neuropeptides based on the calculated monoisotopic [M + H]+ (shown in parentheses below observed m/z). Truncated peptides are denoted by superscripts showing amino acids present from the annotated peptide sequence (i.e. NPLP1-3AA1-AA18 is missing the final three residues of the annotated NPLP1-3 sequence, also shown). Peptide sequences include pre- and post- cleavage residues separated from sequences by a period. C-terminal amidation is denoted by an “a” at end of the peptide sequence. Abbreviations are listed in Table 2 legend. *m/z 925.481 likely corresponds to the convolution of PDNFMRFamide (monoisotopic [M + H]+ = 925.435) and Drostatin-3 (Ast-A3, monoisotopic [M + H]+ = 925.489, see Table 2), which were detected as separate peaks with MALDI-FTICR-MS (Figure 6), hence the comparatively larger m/z error.