Mass spectrometric analysis of single identified neurons of an insect.
The combination of retrograde labelling with dextran-tetramethylrhodamine and MALDI-TOF mass spectrometry was used to analyse for the first time the peptidome of a series of morphologically identified single neurosecretory cells of an insect. Eight postero-lateral cells of the metathoracic ganglion of the American cockroach, Periplaneta americana, were used to demonstrate that: (1) the complete dissection procedure can be documented and (2) the mass spectrometric analysis of the dissected somata results in highly reproducible mass spectra. In total, 21 FMRFamide-related peptides were detected in each of the postero-lateral cells which release their neurosecretions via thoracic perisympathetic organs. Direct analysis of these neurohemal organs confirmed the co-storage of FMRFamide-related peptides. Two additional abundant peptides from thoracic perisympathetic organs which were not detectable in the postero-lateral cells were characterized using ESI-Q-TOF MS/MS. De novo sequencing yielded two related peptides (FERL/IEamides) without any similarity with known peptide families of insects.
Neupert
Susanne
S
Saxon Academy of Sciences, Research Group Jena, Erbertstrasse 1, 07743 Jena, Germany. mail@susanne-neupert.de
Predel
Reinhard
R
D000818:Animals; D003058:Cockroaches; D019835:FMRFamide / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D017952:Ganglia, Invertebrate / Q000166:cytology; D005726:Ganglia, Parasympathetic / Q000737:chemistry / Q000378:metabolism; D007313:Insecta; D009474:Neurons / Q000737:chemistry* / Q000378:metabolism; D009479:Neuropeptides / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
D009479:Neuropeptides; D019835:FMRFamide