Two capa-genes are expressed in the neuroendocrine system of Rhodnius prolixus.
CAPA-peptides have been isolated from a broad range of insect species and are typical of the neurosecretory system of the abdominal ventral nerve cord. In Rhodnius prolixus, which is known to transmit Chagas' disease, CAPA-peptides have potent antidiuretic effects. Recently, two capa-genes were isolated from this hemipteran insect; it was the first description of the occurrence of multiple capa-genes from a single insect species. The expression of peptides from one of these capa-genes was confirmed by mass spectrometry Paluzzi (2008) [10]. In this study, the abdominal neuroendocrine system of R. prolixus was screened for the occurrence of products of the second annotated capa-gene. Single nerve preparations of abdominal segmental nerves 1-3 of R. prolixus were analyzed by MALDI-TOF mass spectrometry and the products of both capa-genes were identified by tandem mass spectrometry. The co-occurrence of the different CAPA-peptides, including CAPA-precursor peptides, in all spectra from abdominal segmental nerves 1 to 3 suggests a common expression of both capa-genes in the same neuroendocrine cells. A comparison of mass spectra obtained from abdominal segmental nerves with those of the subesophageal ganglion (SEG) revealed an obvious differential processing of the CAPA-precursors within the CNS.
Neupert
Susanne
S
Institute of Zoology, Friedrich-Schiller-University, Erbertstrasse 1, Jena 07743, Germany. mail@susanne-neupert.de
Russell
William K
WK
Russell
David H
DH
Predel
Reinhard
R
D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry* / Q000378:metabolism*; D009490:Neurosecretory Systems / Q000378:metabolism; D012239:Rhodnius / Q000235:genetics* / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry
D009479:Neuropeptides